Development of LRFD Design Procedures for Bridge Piles in Iowa-Volume II: Field Testing of Steel Piles in Clay, Sand, and Mixed Soils and Data Analysis

Development of LRFD Design Procedures for Bridge Piles in Iowa-Volume II: Field Testing of Steel Piles in Clay, Sand, and Mixed Soils and Data Analysis
Development of LRFD Procedures for
Bridge Pile Foundations in Iowa
Volume II: Field Testing of Steel Piles in Clay,
Sand, and Mixed Soils and Data Analysis
Final Report
September 2011
Sponsored by
Iowa Highway Research Board
(IHRB Project TR-583)
Iowa Department of Transportation
(InTrans Project 08-312)
About the Bridge Engineering Center
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technologies to help bridge designers/owners design, build, and maintain long-lasting bridges.
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and implement innovative methods, materials, and technologies for improving transportation
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students, faculty, and staff in transportation-related fields.
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Technical Report Documentation Page
1. Report No.
IHRB Project TR-583
2. Government Accession No.
3. Recipient’s Catalog No.
4. Title and Subtitle
Development of LRFD Design Procedures for Bridge Piles in Iowa – Field Testing
of Steel H-Piles in Clay, Sand, and Mixed Soils and Data Analysis (Volume II)
5. Report Date
September 2011
7. Author(s)
Kam Weng Ng, Muhannad T. Suleiman, Matthew Roling, Sherif S. AbdelSalam,
and Sri Sritharan
8. Performing Organization Report No.
InTrans Project 08-312
9. Performing Organization Name and Address
Institute for Transportation
Iowa State University
2711 South Loop Drive, Suite 4700
Ames, IA 50010-8664
10. Work Unit No. (TRAIS)
12. Sponsoring Organization Name and Address
Iowa Highway Research Board
Iowa Department of Transportation
800 Lincoln Way
Ames, IA 50010
13. Type of Report and Period Covered
Final Report
6. Performing Organization Code
11. Contract or Grant No.
14. Sponsoring Agency Code
15. Supplementary Notes
Visit www.intrans.iastate.edu for color PDF files of this and other research reports.
16. Abstract
In response to the mandate on Load and Resistance Factor Design (LRFD) implementations by the Federal Highway Administration
(FHWA) on all new bridge projects initiated after October 1, 2007, the Iowa Highway Research Board (IHRB) sponsored these research
projects to develop regional LRFD recommendations.
The LRFD development was performed using the Iowa Department of Transportation (DOT) Pile Load Test database (PILOT). To
increase the data points for LRFD development, develop LRFD recommendations for dynamic methods, and validate the results of
LRFD calibration, 10 full-scale field tests on the most commonly used steel H-piles (e.g., HP 10 x 42) were conducted throughout Iowa.
Detailed in situ soil investigations were carried out, push-in pressure cells were installed, and laboratory soil tests were performed. Pile
responses during driving, at the end of driving (EOD), and at re-strikes were monitored using the Pile Driving Analyzer (PDA),
following with the CAse Pile Wave Analysis Program (CAPWAP) analysis. The hammer blow counts were recorded for Wave Equation
Analysis Program (WEAP) and dynamic formulas.
Static load tests (SLTs) were performed and the pile capacities were determined based on the Davisson’s criteria. The extensive
experimental research studies generated important data for analytical and computational investigations. The SLT measured loaddisplacements were compared with the simulated results obtained using a model of the TZPILE program and using the modified
borehole shear test method. Two analytical pile setup quantification methods, in terms of soil properties, were developed and validated.
A new calibration procedure was developed to incorporate pile setup into LRFD.
17. Key Words
BST—CAPWAP—dynamic analysis—LRFD—mBST—PILOT—PDA—static
load test—WEAP
18. Distribution Statement
No restrictions.
19. Security Classification (of this
report)
Unclassified.
21. No. of Pages
22. Price
226
NA
Form DOT F 1700.7 (8-72)
20. Security Classification (of this
page)
Unclassified.
Reproduction of completed page authorized
Development of LRFD Design Procedures for Bridge Piles in
Iowa – Field Testing of Steel H-Piles in Clay, Sand, and
Mixed Soils and Data Analysis
Final Report-Volume II
September 2011
Principal Investigator
Sri Sritharan
Wilson Engineering Professor
Department of Civil, Construction, and Environmental Engineering, Iowa State University
Research Associate
Muhannad T. Suleiman
Assistant Professor
Department of Civil and Environmental Engineering, Lehigh University
Research Assistant
Kam Weng Ng
Matthew Roling
Sherif S. AbdelSalam
Authors
Kam Weng Ng, Muhannad T. Suleiman, Matthew Roling, Sherif S. AbdelSalam,
and Sri Sritharan
Sponsored by
The Iowa Highway Research Board
(IHRB Project TR-583)
Preparation of this report was financed in part
through funds provided by the Iowa Department of Transportation
through its research management agreement with the
Institute for Transportation
(In Trans Project 08-312)
A report from
Institute for Transportation
Iowa State University
2711 South Loop Drive, Suite 4700
Ames, IA 50010-8664
Phone: 515-294-8103
Fax: 515-294-0467
www.intrans.iastate.edu
TABLE OF CONTENTS
ACKNOWLEDGMENTS .............................................................................................................xv
CHAPTER 1: OVERVIEW .............................................................................................................1
1.1. Background ...................................................................................................................1
1.2. Scope of Research Projects ...........................................................................................1
1.3. Report Content ..............................................................................................................2
CHAPTER 2: SELECTION OF TEST LOCATIONS ....................................................................3
2.1. Criteria of Selecting Test Locations .............................................................................3
2.2. Selected Test Pile Locations .........................................................................................5
CHAPTER 3: SITE CHARACTERIZATION ................................................................................7
3.1. Standard Penetration Tests (SPT) .................................................................................7
3.2. Cone Penetration Tests (CPT) ....................................................................................10
3.3. Borehole Shear Tests (BST) .......................................................................................14
3.4. Modified Borehole Shear Tests (mBST) ....................................................................16
3.5. Laboratory Soil Tests ..................................................................................................18
3.6. Pore Water and Lateral Earth Pressure Measurements ...............................................23
CHAPTER 4: FULL-SCALE TESTS ...........................................................................................28
4.1. Pile Type and Properties .............................................................................................28
4.2. Hammer Types ............................................................................................................29
4.3. Strain Gauge Instrumentation .....................................................................................30
4.4. Pile Driving Analyzer (PDA) Tests ............................................................................33
4.5. CAse Pile Wave Analysis Program (CAPWAP) ........................................................40
4.6. Wave Equation Analysis Program (WEAP) ...............................................................44
4.7. Vertical Static Load Tests ...........................................................................................56
CHAPTER 5: INTERPRETATION AND ANALYSIS OF FIELD DATA .................................64
5.1. Introduction .................................................................................................................64
5.2. Pile Resistance Distribution ........................................................................................64
5.3. Load Transfer Analysis Using mBST and TZPILE Program .....................................67
5.4. Interpretation of Push-In Pressure Cell Measurements ..............................................67
5.5. Pile Responses over Time ...........................................................................................69
5.6. Pile Setup in Clay Profile ............................................................................................75
CHAPTER 6: SUMMARY............................................................................................................98
CHAPTER 7: CONCLUSIONS ..................................................................................................100
REFERENCES ............................................................................................................................103
APPENDIX A: LOCATIONS OF TEST PILES AND IN SITU SOIL TESTS .........................107
APPENDIX B: RESULTS OF IN SITU SOIL INVESTIGATIONS AND SOIL PROFILES ..112
B.2. Estimated Soil Profiles and Properties Based on Cone Penetration Tests (CPT) ....123
B.3. Pore Water Pressure Measurements Using Cone Penetration Tests (CPT) .............127
v
B.4. Borehole Shear Test and modified Borehole Shear Test Results.............................131
B.5. Soil Classification and Properties Obtained from Gradation and Atterberg
Limit Tests .......................................................................................................................143
B.6. Total Lateral Earth and Pore Water Pressure Measurements using Push-in
Pressure Cells (PCs) .........................................................................................................146
APPENDIX C: DETAILS OF FULL-SCALE PILE TESTS ......................................................149
C.1. Locations of Strain Gauges along Test Piles ............................................................150
C.2. Pile Driving Analyzer (PDA) Measurements...........................................................158
C.3. Schematic Drawing and Configuration of the Vertical Static Load Tests ...............179
C.4. Static Load Test Load and Displacement .................................................................189
APPENDIX D: DATA INTERPRETATION AND ANALYSIS ...............................................194
D.1. Static Load Test Pile Force Transferred Profiles .....................................................194
D.2. Shaft Resistance Distribution ...................................................................................200
D.3. Pile Driving Resistance ............................................................................................204
D.4. Relationship between Soil Properties and Pile Shaft Resistance Gain ....................208
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LIST OF FIGURES
Figure 2.1. Iowa geological map and the test pile locations ............................................................4
Figure 2.2. Distribution of steel H-piles by soil profiles .................................................................5
Figure 3.1. Typical Standard Penetration Test (SPT) ......................................................................8
Figure 3.2. In-situ soil investigations and soil profile for ISU5 at Clarke County (CPT 3) ............9
Figure 3.3. Typical Cone Penetration Test (CPT) .........................................................................10
Figure 3.4. Increase in pore pressure for ISU5 at a depth of 38.55-ft ...........................................12
Figure 3.5. Pore pressure dissipation result for ISU2 at a depth of 35.4-ft ...................................12
Figure 3.6. The conventional Borehole Shear Test (BST) equipment (adapted from Handy,
1986) ..................................................................................................................................14
Figure 3.7. BST generated Mohr-Coulomb shear failure envelope for ISU5 at 8.83-ft depth ......15
Figure 3.8. BST generated shear stress-displacement relationship at different applied normal
stress for ISU5 at 8.83-ft depth ..........................................................................................15
Figure 3.9. The modified Borehole Shear Test (mBST) equipment (adapted from Handy,
1986) ..................................................................................................................................16
Figure 3.10. mBST generated shear stress-displacement relationship at different applied
normal stress for ISU5 at 8.83-ft depth ..............................................................................17
Figure 3.11. mBST generated Mohr-Coulomb interface shear failure envelop for ISU5 at
8.83 ft depth .......................................................................................................................17
Figure 3.12. Laboratory soil tests ..................................................................................................18
Figure 3.13. Grain size distribution curve for disturbed sample DS-1 at 3 ft depth of ISU5 ........19
Figure 3.14. Laboratory soil consolidation tests ............................................................................21
Figure 3.15. The e-log(σ) curve for evaluating pre-consolidation stress from Casagrande’s
Method for specimen Clarke-25 ........................................................................................22
Figure 3.16. Measurement of pore water and lateral earth pressures using Geokon push-in
pressure cells at the field ....................................................................................................24
Figure 3.17. Total lateral earth pressure and pore water pressure measurements from PC1 at
test pile ISU5 with respect to the time ...............................................................................26
Figure 3.18. Total lateral earth pressure and pore water pressure measurements from PC3
and PC4 at test pile ISU6 with respect to the time ............................................................27
Figure 4.1. Cross sectional view of the steel H-piles .....................................................................29
Figure 4.2. Single acting open end diesel hammer (adapted from Pile Dynamics, Inc., 2005) .....30
Figure 4.3. Strain gauges arrangement at a cross sectional view of a steel H-pile ........................31
Figure 4.4. Strain gauges installation, protection, and covered by angles .....................................31
Figure 4.5. Angle bars were chamfered to form a pointed end at pile toe .....................................31
Figure 4.6. Location of strain gauges along the ISU5 test pile at Clarke County .........................32
Figure 4.7. Typical Pile Driving Analyzer (PDA) set up (from Pile Dynamics, Inc., 1996) ........35
Figure 4.8. PDA force and velocity records during driving and at EOD for ISU5 .......................36
Figure 4.9. PDA force and velocity records during re-strikes for ISU5 ........................................37
Figure 4.10. Wave-up and velocity measurement for ISU5 at EOD used to determine shaft
resistance ............................................................................................................................38
Figure 4.11. Typical CAPWAP model for ISU5 at EOD ..............................................................41
Figure 4.12. Results of CAPWAP signals matching for ISU5 at EOD .........................................42
Figure 4.13. Wave equation models for different hammers (adapted from Hannigan et al.
1998) ..................................................................................................................................44
Figure 4.14. WEAP generated bearing graph for ISU5 at EOD using the Iowa DOT method .....54
vii
Figure 4.15. WEAP estimated pile stresses for ISU5 at EOD using the Iowa DOT method ........55
Figure 4.16. Minimal buckling on flanges at pile head .................................................................57
Figure 4.17. Schematic drawing of vertical static load test for ISU5 at Clarke County ................58
Figure 4.18. Configuration of two anchor piles and a test pile for ISU5 at Clarke County ..........59
Figure 4.19. Setting up of the static load test .................................................................................60
Figure 4.20. Pile top vertical displacement transducers instrumentation ......................................62
Figure 4.21. A load-displacement curve and Davisson’s criteria for ISU5 at Clarke County .......62
Figure 5.1. Pile force distribution along the embedded pile length of test pile ISU5 ....................65
Figure 5.2. SLT measured and CAPWAP estimated pile shaft resistance distributions for test
pile ISU5 ............................................................................................................................66
Figure 5.3. Pile driving resistance in terms of hammer blow count ..............................................70
Figure 5.4. Relationship between total pile resistance and time for clay profile ...........................71
Figure 5.5. Relationship between total pile resistance and time for mixed soil profile .................72
Figure 5.6. Relationship between total pile resistance and time for sand profile ..........................72
Figure 5.7. Relationship between resistance components and time for clay profile......................74
Figure 5.8. Relationship between resistance components and time for mixed soil profile ...........75
Figure 5.9. Relationship between soil properties and increase in shaft resistance for ISU5 .........76
Figure 5.10. Correlations of both vertical and horizontal coefficients of consolidation with
SPT N-values .....................................................................................................................77
Figure 5.11. Relationships between percent gain in pile capacity and (a) SPT N-value, (b) Ch,
(c) Cv, and (d) PI, estimated at a time of 1 day after EOD for all sites..............................79
Figure 5.12. Linear best fit lines of normalized pile resistance and logarithmic normalized
time ....................................................................................................................................82
Figure 5.13. Correlation between pile setup rate (C) and soil parameters with pile radius ...........82
Figure 5.14. Correlation between pile setup rate (C) and average SPT N-value ...........................84
Figure 5.15. Pile setup design charts for WEAP and CAPWAP ...................................................85
Figure 5.16. Pile setup site verification charts for WEAP and CAPWAP ....................................86
Figure 5.17. Pile setup comparison and validation ........................................................................88
Figure 5.18. Pile setup confidence levels.......................................................................................90
Figure 5.19. Different uncertainties involved between EOD and setup ........................................93
Figure 5.20. Resistance factor for pile setup resistance .................................................................94
Figure 5.21. Histogram and theoretical normal distribution of α values based on information
of production piles at ISU field test sites ...........................................................................95
Figure 5.22. Histogram and theoretical normal distribution of α values based on additional
data of production piles in Iowa.........................................................................................97
Figure A.1. Test Pile ISU1 at Mahaska County...........................................................................107
Figure A.2. Test Pile ISU2 at Mills County.................................................................................108
Figure A.3. Test Pile ISU3 at Polk County..................................................................................108
Figure A.4. Test Pile ISU4 at Jasper County ...............................................................................109
Figure A.5. Test Pile ISU5 at Clark County ................................................................................109
Figure A.6. Test Piles ISU6 and ISU7 at Buchanan County .......................................................110
Figure A.7. Test Pile ISU8 at Poweshiek County ........................................................................110
Figure A.8. Test Pile ISU9 at Des Moines County ......................................................................111
Figure A.9. Test Pile ISU10 at Cedar County .............................................................................111
viii
Figure B.1.1. In-situ soil investigations and soil profile for ISU1 at Mahaska County...............113
Figure B.1.2. In-situ soil investigations and soil profile for ISU2 at Mills County.....................114
Figure B.1.3. In-situ soil investigations and soil profile for ISU3 at Polk County ......................115
Figure B.1.4. In-situ soil investigations and soil profile for ISU4 at Jasper County ...................116
Figure B.1.5. Cone Penetration Tests and soil profile for ISU5 at Clarke County ......................117
Figure B.1.6. In-situ soil investigations and soil profile for ISU5 at Clarke County ..................118
Figure B.1.7. In-situ soil investigations and soil profile for ISU6 and ISU7 at Buchanan
County ..............................................................................................................................119
Figure B.1.8. In-situ soil investigations and soil profile for ISU8 at Poweshiek County ............120
Figure B.1.9. In-situ soil investigations and soil profile for ISU9 at Des Moines County ..........121
Figure B.1.10. In-situ soil investigations and soil profile for ISU10 at Cedar County ...............122
Figure B.3.1. CPT pore water pressure dissipation tests at ISU2 Mills County ..........................127
Figure B.3.2. CPT pore water pressure dissipation tests at ISU3 Polk County ...........................127
Figure B.3.3. CPT pore water pressure dissipation tests at ISU4 Jasper County ........................128
Figure B.3.4. CPT pore water pressure dissipation tests at ISU5 Clarke County........................128
Figure B.3.5. CPT pore water pressure dissipation tests at ISU6 and ISU7 Buchanan County ..129
Figure B.3.6. CPT pore water pressure dissipation tests at ISU8 Poweshiek County .................129
Figure B.3.7. CPT pore water pressure dissipation tests at ISU9 Des Moines County ...............130
Figure B.4.1. ISU1 at 3-ft depth (BST) .......................................................................................131
Figure B.4.2. ISU1 at 8-ft depth (BST) .......................................................................................131
Figure B.4.3. ISU1 at 16-ft depth (BST) .....................................................................................131
Figure B.4.4. ISU2 at 5-ft depth (BST) .......................................................................................132
Figure B.4.5. ISU2 at 20-ft depth (BST) .....................................................................................132
Figure B.4.6. ISU3 at 4-ft depth (BST) .......................................................................................132
Figure B.4.7. ISU3 at 23-ft depth (BST) .....................................................................................133
Figure B.4.8. ISU4 at 27-ft depth (BST & mBST) ......................................................................133
Figure B.4.9. ISU4 at 46-ft depth (BST & mBST) ......................................................................133
Figure B.4.10. BST and mBST generated shear stress-displacement relationships for ISU4
at 27-ft depth ....................................................................................................................134
Figure B.4.11. BST and mBST generated shear stress-displacement relationships for ISU4
at 46-ft depth ....................................................................................................................134
Figure B.4.12. ISU5 at 8.83-ft depth (BST & mBST) .................................................................135
Figure B.4.13. ISU5 at 23.83-ft depth (BST & mBST) ...............................................................135
Figure B.4.14. ISU5 at 35.83-ft depth (BST & mBST) ...............................................................135
Figure B.4.15. BST and mBST generated shear stress-displacement relationships for ISU5
at 8.83-ft depth .................................................................................................................136
Figure B.4.16. BST and mBST generated shear stress-displacement relationships for ISU5
at 23.83-ft depth ...............................................................................................................136
Figure B.4.17. BST and mBST generated shear stress-displacement relationships for ISU5
at 35.83-ft depth ...............................................................................................................137
Figure B.4.18. ISU6 and ISU7 at 8.3-ft depth (BST & mBST) ...................................................137
Figure B.4.19. ISU6 and ISU7 at 11.89-ft depth (BST & mBST) ...............................................138
Figure B.4.20. ISU6 and ISU7 at 50.3-ft depth (BST & mBST) .................................................138
ix
Figure B.4.21. BST and mBST generated shear stress-displacement relationships for ISU6
and ISU7 at 8.3-ft depth ...................................................................................................138
Figure B.4.22. BST and mBST generated shear stress-displacement relationships for ISU6
and ISU7 at 11.89-ft depth ...............................................................................................139
Figure B.4.23. BST and mBST generated shear stress-displacement relationships for ISU6
and ISU7 at 50.3-ft depth .................................................................................................139
Figure B.4.24. ISU8 at 9-ft depth (BST & mBST) ......................................................................140
Figure B.4.25. ISU8 at 23-ft depth (BST & mBST) ....................................................................140
Figure B.4.26. ISU8 at 45-ft depth (BST & mBST) ....................................................................140
Figure B.4.27. BST and mBST generated shear stress-displacement relationships for ISU8 at
9-ft depth ..........................................................................................................................141
Figure B.4.28. BST and mBST generated shear stress-displacement relationships for ISU8 at
23-ft depth ........................................................................................................................141
Figure B.4.29. BST and mBST generated shear stress-displacement relationships for ISU8 at
45-ft depth ........................................................................................................................142
Figure B.6.1. Total lateral earth and pore water pressure measurements from PC1 at test pile
ISU7 .................................................................................................................................146
Figure B.6.2. Total lateral earth and pore water pressure measurements from PC4 at test pile
ISU8 .................................................................................................................................147
Figure B.6.3. Total lateral earth and pore water pressure measurements from PC4 at test pile
ISU10 ...............................................................................................................................148
Figure C.1.1. Location of strain gauges along the ISU2 test pile at Mills County ......................150
Figure C.1.2. Location of strain gauges along the ISU3 test pile at Polk County .......................151
Figure C.1.3. Location of strain gauges along the ISU4 test pile at Jasper County ....................152
Figure C.1.4. Location of strain gauges along the ISU6 test pile at Buchanan County ..............153
Figure C.1.5. Location of strain gauges along the ISU7 test pile at Buchanan County ..............154
Figure C.1.6. Location of strain gauges along the ISU8 test pile at Poweshiek County .............155
Figure C.1.7. Location of strain gauges along the ISU9 test pile at Des Moines County ...........156
Figure C.1.8. Location of strain gauges along the ISU10 test pile at Cedar County ...................157
Figure C.2.1. PDA force and velocity records for ISU1 ..............................................................158
Figure C.2.2. PDA force and velocity records for ISU2 ..............................................................159
Figure C.2.3. PDA force and velocity records for ISU3 ..............................................................161
Figure C.2.4. PDA force and velocity records for ISU4 ..............................................................163
Figure C.2.5. PDA force and velocity records for ISU5 ..............................................................166
Figure C.2.6. PDA force and velocity records for ISU6 ..............................................................169
Figure C.2.7. PDA force and velocity records for ISU7 ..............................................................171
Figure C.2.8. PDA force and velocity records for ISU8 ..............................................................174
Figure C.2.9. PDA force and velocity records for ISU9 ..............................................................176
Figure C.2.10. PDA force and velocity records for ISU10 ..........................................................178
x
Figure C.3.1. Configuration of four anchor piles and a steel test pile for ISU1 at Mahaska
County ..............................................................................................................................179
Figure C.3.2. Configuration of two anchor piles and a steel test pile for ISU2 at Mills
County ..............................................................................................................................179
Figure C.3.3. Configuration of two anchor piles and a steel test pile for ISU3 at Polk
County ..............................................................................................................................179
Figure C.3.4. Configuration of two anchor piles and a steel test pile for ISU4 at Jasper
County ..............................................................................................................................180
Figure C.3.5. Configuration of two anchor piles and two steel test piles for ISU6 and ISU7
at Buchanan County .........................................................................................................180
Figure C.3.6. Configuration of two anchor piles and a steel test pile for ISU8 at Poweshiek
County ..............................................................................................................................180
Figure C.3.7. Configuration of two anchor piles and a steel test pile for ISU9 at Des Moines
County ..............................................................................................................................181
Figure C.3.8. Configuration of two anchor piles and a steel test pile for ISU10 at Cedar
County ..............................................................................................................................181
Figure C.3.9. Schematic drawing of vertical static load test for ISU1 at Mahaska County ........182
Figure C.3.10. Schematic drawing of vertical static load test for ISU2 at Mills County ............183
Figure C.3.11. Schematic drawing of vertical static load test for ISU3 at Polk County .............184
Figure C.3.12. Schematic drawing of vertical static load test for ISU4 at Jasper County ...........185
Figure C.3.13. Schematic drawing of vertical static load tests for ISU6 and ISU7 at
Buchanan County .............................................................................................................186
Figure C.3.14. Schematic drawing of vertical static load test for ISU8 at Poweshiek County ...187
Figure C.3. 15. Schematic drawing of vertical static load tests for ISU9 and ISU10 at
Des Moines County and Cedar County respectively .......................................................188
Figure C.4.1. A load-displacement curve and Davisson’s criteria for ISU1 at Mahaska
County ..............................................................................................................................189
Figure C.4.2. A load-displacement curve and Davisson’s criteria for ISU2 at Mills County .....189
Figure C.4.3. A load-displacement curve and Davisson’s criteria for ISU3 at Polk County ......190
Figure C.4.4. A load-displacement curve and Davisson’s criteria for ISU4 at Jasper County ....190
Figure C.4.5. A load-displacement curve and Davisson’s criteria for ISU6 at Buchanan
County ..............................................................................................................................191
Figure C.4.6. A load-displacement curve and Davisson’s criteria for ISU7 at Buchanan
County ..............................................................................................................................191
Figure C.4.7. A load-displacement curve and Davisson’s criteria for ISU8 at Poweshiek
County ..............................................................................................................................192
Figure C.4.8. A load-displacement curve and Davisson’s criteria for ISU9 at Des Moines
County ..............................................................................................................................192
Figure C.4.9. A load-displacement curve and Davisson’s criteria for ISU10 at Cedar
County ..............................................................................................................................193
xi
Figure D.1.1. Pile force distribution along the embedded pile length of the test pile ISU2 ........194
Figure D.1.2. Pile force distribution along the embedded pile length of the test pile ISU3 ........195
Figure D.1.3. Pile force distribution along the embedded pile length of the test pile ISU4 ........196
Figure D.1.4. Pile force distribution along the embedded pile length of the test pile ISU6 ........197
Figure D.1.5. Pile force distribution along the embedded pile length of the test pile ISU8 ........198
Figure D.1.6. Pile force distribution along the embedded pile length of the test pile ISU9 ........199
Figure D.2.1. SLT measured and CAPWAP estimated pile shaft resistance distributions
for test pile ISU2 ..............................................................................................................200
Figure D.2.2. SLT measured and CAPWAP estimated pile shaft resistance distributions
for test pile ISU3 ..............................................................................................................200
Figure D.2.3. SLT measured and CAPWAP estimated pile shaft resistance distributions
for test pile ISU4 ..............................................................................................................201
Figure D.2.4. CAPWAP estimated pile shaft resistance distributions for test pile ISU6 ............201
Figure D.2.5. CAPWAP estimated pile shaft resistance distributions for test pile ISU7 ............202
Figure D.2.6. SLT measured and CAPWAP estimated pile shaft resistance distributions
for test pile ISU8 ..............................................................................................................202
Figure D.2.7. SLT measured and CAPWAP estimated pile shaft resistance distributions
for test pile ISU9 ..............................................................................................................203
Figure D.2.8. CAPWAP estimated pile shaft resistance distributions for test pile ISU10 ..........203
Figure D.3.1. Pile driving resistances for ISU1 and ISU2 in terms of hammer blow count .......204
Figure D.3.2. Pile driving resistances for ISU3 and ISU4 in terms of hammer blow count .......205
Figure D.3.3. Pile driving resistances for ISU6 and ISU7 in terms of hammer blow count .......206
Figure D.3.4. Pile driving resistance for ISU10 (sand profile) in terms of hammer blow
count .................................................................................................................................207
Figure D.4.1. Relationship between soil properties and shaft resistance gain for ISU2..............208
Figure D.4.2. Relationship between soil properties and shaft resistance gain for ISU3..............208
Figure D.4.3. Relationship between soil properties and shaft resistance gain for ISU4..............209
Figure D.4.4. Relationship between soil properties and shaft resistance gain for ISU6..............209
xii
LIST OF TABLES
Table 3.1. Summary of in-situ and laboratory soil investigations ...................................................7
Table 3.2. Summary of soil parameters at depths of CPT dissipation tests ...................................13
Table 3.3. Summary of soil properties for ISU5 based on CPT ....................................................13
Table 3.4. Soil classification and properties for ISU5 obtained from gradation and
Atterberg’s limit tests .........................................................................................................20
Table 3.5. Summary of the consolidation test results and analyses ...............................................23
Table 3.6. Calibrated factors and zero reading temperature for each pressure cell .......................25
Table 4.1. A572 Grade 50 (Fy = 50 ksi) steel H-pile properties ....................................................28
Table 4.2. Summary of hammer information.................................................................................29
Table 4.3. Schedule of re-strikes and PDA tests ............................................................................33
Table 4.4. Summary of Case damping factors ...............................................................................34
Table 4.5. Summary of Jc, PDA estimated pile static (RMX) and shaft resistances (SFR) ...........38
Table 4.6. Pile damage classification .............................................................................................40
Table 4.7. Summary of CAPWAP estimated total pile resistances and shaft resistances .............42
Table 4.8. Summary of CAPWAP estimated soil quake values ....................................................43
Table 4.9. Summary of CAPWAP estimated soil Smith’s damping factors .................................43
Table 4.10. Summary of static analysis methods used in the five soil profile input procedures ...47
Table 4.11. Soil Parameters for cohesionless soils ........................................................................48
Table 4.12. Soil Parameters for cohesive soils ..............................................................................48
Table 4.13. Empirical values for ø, Dr, and γ of cohesionless soils based on Bowles (1996) ......48
Table 4.14. Empirical values for qu and γ of cohesive soils based on Bowles (1996) ..................48
Table 4.15. Iowa pile design chart for friction bearing Grade 50 steel H-piles .............................49
Table 4.16. Iowa pile design chart for end bearing Grade 50 steel H-piles ...................................50
Table 4.17. Revised Iowa pile design chart used in WEAP for friction bearing Grade 50
steel H-piles .......................................................................................................................51
Table 4.18. Revised Iowa pile design chart used in WEAP for end bearing Grade 50 steel
H-piles ................................................................................................................................52
Table 4.19. WEAP recommended soil quake values (Pile Dynamics, Inc., 2005) ........................53
Table 4.20. WEAP recommended Smith’s damping factors used in ST, SA, Driven and
Iowa Blue Book (Pile Dynamics, Inc., 2005) ....................................................................53
Table 4.21. Damping factors used in the Iowa DOT method ........................................................53
Table 4.22. Measured hammer blow count at EOD and re-strikes ................................................54
Table 4.23. Summary of WEAP estimated pile capacities for all loading stages and all test
piles using different soil input options ...............................................................................55
Table 4.24. Summary of static load test results .............................................................................63
Table 5.1. Summary of shaft resistance and end bearing from static load test results and last
re-strike using CAPWAP ...................................................................................................66
Table 5.2. Percent increase in pile resistance based on CAPWAP and SLT measurements .........73
Table 5.3. Average soil properties along pile shaft and near pile toe ............................................78
Table 5.4. The consolidation (fc) and remolding recovery (fr) factors...........................................83
Table 5.5. Scale (a) and concave (b) factors ..................................................................................84
Table 5.6. Summary of the twelve data records from PILOT .......................................................87
Table 5.7. Summary of the estimated pile resistance including setup ...........................................87
Table 5.8. Anticipated errors of the pile setup methods at various confidence levels ...................89
Table 5.9. Summary of resistance ratio estimators for EOD and setup .........................................92
xiii
Table 5.10. Summary of information on production piles at ISU test sites ...................................95
Table 5.11. Summary of additional data on production piles in Iowa ...........................................96
Table B.2.1. Summary of soil properties for ISU1 based on CPT...............................................123
Table B.2.2. Summary of soil properties for ISU2 based on CPT...............................................123
Table B.2.3. Summary of soil properties for ISU3 based on CPT...............................................124
Table B.2.4. Summary of soil properties for ISU4 based on CPT...............................................124
Table B.2.5. Summary of soil properties for ISU5 based on CPT...............................................125
Table B.2.6. Summary of soil properties for ISU6 and ISU7 based on CPT ..............................125
Table B.2.7. Summary of soil properties for ISU8 based on CPT...............................................126
Table B.2.8. Summary of soil properties for ISU9 based on CPT...............................................126
Table B.2.9. Summary of soil properties for ISU10 based on CPT.............................................126
Table B.5.1. Soil classification and properties for ISU1 from gradation and Atterberg limit
tests ..................................................................................................................................143
Table B.5.2. Soil classification and properties for ISU2 from gradation and Atterberg limit
tests ..................................................................................................................................143
Table B.5.3. Soil classification and properties for ISU3 from gradation and Atterberg limit
tests ..................................................................................................................................143
Table B.5.4. Soil classification and properties for ISU4 from gradation and Atterberg limit
tests ..................................................................................................................................144
Table B.5.5. Soil classification and properties for ISU5 from gradation and Atterberg limit
tests ..................................................................................................................................144
Table B.5.6. Soil classification and properties for ISU6 & ISU7 from gradation and Atterberg
limit tests ..........................................................................................................................144
Table B.5.7. Soil classification and properties for ISU8 from gradation and Atterberg limit
tests ..................................................................................................................................145
Table B.5.8. Soil classification and properties for ISU9 from gradation and Atterberg limit
tests ..................................................................................................................................145
Table B.5.9. Soil classification and properties for ISU10 from gradation and Atterberg limit
tests ..................................................................................................................................145
xiv
ACKNOWLEDGMENTS
The authors would like to thank the Iowa Highway Research Board (IHRB) for sponsoring the
research project: TR-583. We would like to thank the Technical Advisory Committee of the
research for their guidance and Kyle Frame of Iowa DOT for his assistance with the PDA tests.
Particularly the following individuals served on the Technical Advisory Committee of this
research project: Ahmad Abu-Hawash, Dean Bierwagen, Lyle Brehm, Ken Dunker, Kyle Frame,
Steve Megivern, Curtis Monk, Michael Nop, Gary Novey, John Rasmussen and Bob Stanley.
The members of this committee represent Office of Bridges and Structures, Office of Design,
and Office of Construction of the Iowa DOT, FHWA Iowa Division, and Iowa County
Engineers. Thanks are extended to Team Services of Des Moines, Iowa, for conducting the SPT
tests and Geotechnical Services, Inc. (GSI) of Des Moines, Iowa, for conducting the CPT tests.
A special thank you is due to Douglas Wood in setting up the DAS system and helping on static
load tests. Also, special thanks are due to Donald Davidson and Erica Velasco for the assistance
with laboratory soil tests. We would also like to thank the following contractors for their
contribution to the field tests:
ISU1 at Mahaska County
ISU2 at Mills County
ISU3 at Polk County
ISU4 at Jasper County
ISU5 at Clarke County
ISU6 at Buchanan County
ISU7 at Buchanan County
ISU8 at Poweshiek County
ISU9 at Des Moines County
ISU10 at Cedar County
– Cramer & Associates
– Dixon Construction Co.
– Cramer & Associates
– Peterson Contractors, Inc.
– Herberger Construction
– Taylor Construction, Inc
– Taylor Construction, Inc
– Peterson Contractors, Inc.
– Iowa Bridge and Culvert, LC
– United Contractors, Inc
xv
CHAPTER 1: OVERVIEW
1.1. Background
Since the mid-1980s, the Load and Resistance Factor Design (LRFD) method has been
progressively developed to ensure a better and more uniform reliability of bridge design in the
United States. The Federal Highway Administration (FHWA) has mandated that all new bridges
initiated after October 1, 2007 will follow the LRFD design approach. Because of high
variability in soil characteristics, complexity in soil-pile interaction, and difficulty in predicting a
sensible pile resistance and driving stress, design in foundation elements pose more challenges
than the superstructure elements. To improve the economy of foundation design, American
Association of State Highway and Transportation Officials (AASHTO) has recommended that
higher resistance factors be used in the LRFD design method at a specific region where research
has been conducted and/or past foundation data is available for validating the changes.
1.2. Scope of Research Projects
In response to the above recommendation, the Iowa Highway Research Board (IHRB) sponsored
a research project, TR-573, in July 2007 to develop resistance factors for pile design using the
Pile Load Test database (PILOT) from past projects completed by the Iowa Department of
Transportation (Iowa DOT) from 1966 to late 1980s. The details of the PILOT database are
described in the LRFD Report Volume I. Although the PILOT database enables the
development of the LRFD resistance factors for static methods, dynamic formulas and Wave
Equation Analysis Program (WEAP) from the static load test data, it is not inclusive of all soil
profiles in Iowa and provides only a limited amount of reliable data. Also, the PILOT database
does not include Pile Driving Analyzer (PDA) driving data, which should be used for providing a
reliable construction control method, predicting pile damage resulting from pile driving,
determining the contribution of shaft friction and end bearing to pile resistance, and developing
the LRFD resistance factors for PDA and CAse Pile Wave Analysis Program (CAPWAP).
Hence, two (2) add-on research projects (TR-583 and TR-584) were proposed and included to
conduct ten (10) field tests and obtain a complete set of data. The commonly used steel H-piles
in Iowa for bridge foundations were chosen in the ten (10) field tests that cover all five (5)
geological regions in the State of Iowa. These field tests involved detailed site characterization
using both in-situ subsurface investigations, which consisted of Standard Penetration Tests
(SPTs), Piezocone Penetration Tests (CPTs) with pore water pressure dissipation measurements,
Borehole Shear Tests (BSTs), and modified Borehole Shear Tests (mBSTs), as well as laboratory
soil classification and consolidation tests. In addition, push-in pressure cells were installed
within 24-in. (610-mm) from designated pile flanges to measure the changes in lateral earth
pressure and pore water pressure during pile driving, re-strikes and static load tests (SLTs). Prior
to pile driving, the test piles were instrumented with strain gauges along the embedded pile
length for axial strain measurements. In addition, two PDA strain transducers and two
accelerometers were installed 30-in. (750-mm) below the pile head to record the pile strains and
accelerations during driving and re-strikes, which were converted into force and velocity records
for CAPWAP analyses. During pile driving and re-strikes, pile driving resistances (hammer blow
count) were recorded for WEAP analyses. After completing all the re-strikes on the test piles,
vertical SLTs were performed on test piles following the “Quick Test” procedure of ASTM
D1143.
1
The field tests provided the following data: (1) detailed soil profiles with appropriate soil
parameters; (2) lateral earth and pore water pressure measurements from the push-in pressure
cells; (3) strain and acceleration measurements using the PDA during driving, at end of driving
(EOD) and at the beginning of re-strikes (BOR); and (4) vertical static load test data.
Interpretation and analysis of data was performed using static analysis methods, dynamic
analysis methods and dynamic formulas. The completion of these three (3) projects will: (1) lay
the foundation for developing a comprehensive database that can be populated at a reduced cost;
(2) establish LRFD specifications for designing steel H-piles using static methods, dynamic
analysis methods and dynamic formulas; (3) develop a reliable construction control method
using the dynamic analysis methods and dynamic formulas; and (4) quantify the increase in pile
capacities as a function of time (pile setup).
1.3. Report Content
The purpose of this report is to clearly depict the site characterization work and the field tests of
the ten (10) steel H-piles installed in different soil profiles in the State of Iowa. This report
consists of five (5) chapters describing the experimental work and a summary of the results.
Three (3) appendices include the information and results of the field tests and laboratory tests.
The content of each chapter is as follows:
Chapter 1: OVERVIEW – A brief description of the background of the LRFD
specifications development in the United States and the scope of the IHRB LRFD
research projects.
Chapter 2: SELECTION OF TEST LOCATIONS – A brief description of the process
and criteria of selecting the locations of the ten (10) field tests on steel H-piles and their
corresponding geological regions in the State of Iowa.
Chapter 3: SITE CHARACTERIZATION – Site Characterization: Description of the
geotechnical subsurface investigations of characterizing the soil profile at each test site
using in-situ and laboratory soil tests.
Chapter 4:FULL-SCALE TESTS – Field Testing: A complete description of the steel
H-piles and hammers used at the test sites, pile instrumentation, pile driving, PDA tests,
dynamic analysis methods and vertical static load tests.
Chapter 5: INTERPRETATION AND ANALYSIS OF FIELD DATA – Performed
concurrent analytical and computational investigations using the field test results
combined with some data from the PILOT database.
Chapter 6: SUMMARY– Summary of the site characterizations and the field tests.
Chapter 7: CONCLUSIONS – A summary of the important conclusions made from the
interpretation and analysis of field test results.
2
CHAPTER 2: SELECTION OF TEST LOCATIONS
2.1. Criteria of Selecting Test Locations
The Iowa DOT provided a list of possible sites for the 10 field tests from current and upcoming
bridge construction projects. In order to select proper locations for the field tests, six criteria
listed below were established:
1) The test locations covered all possible geological regions in the State of Iowa;
2) The test piles were installed at locations, which covered all soil profiles in Iowa;
3) The number of test piles was proportioned to increase the data set with a soil profile that
is scarce in the PILOT database;
4) The test locations were selected at locations with relatively less dense soil;
5) The test locations avoided sites with shallow bedrock; and
6) Despite satisfying the above criteria, the selection of the test locations was eventually
decided based upon the nature of bridge construction projects.
2.1.1. Geological Regions in the State of Iowa
Iowa has five geological regions as shown in Figure 2.1. The five geological regions are
alluvium, loess, Wisconsin glacial, loamy glacial and loess on top of glacial. The test pile
locations are selected and situated in all geological regions.
2.1.2. Soil Profiles
Following AASHTO, soil profiles are categorized into sand, clay and mixed soils. Sand profile
is defined as having more than 70 percent of an embedded pile length surrounded with sandy
soil. Similar to the sand profile, clay profile is defined as having more than 70 percent of an
embedded pile length surrounded with clayey soil. If a profile matches neither the sand nor clay
profile, it is classified as a mixed profile. A mixed profile usually consists of two or more soil
layers, with a soil profile containing less than 70% sand or clay surrounding the embedded pile
length. Prior to performing the detailed site characterization, preliminary soil profiles are
identified from the available Iowa DOT boring logs, as briefly listed in Table 2.1. The soil
profiles are confirmed afterward by the detailed soil tests described in Section 3. Hence, the
selected test locations as shown in Figure 2.1 are seen to adequately cover all three soil profiles.
2.1.3. Increase Data Set
Figure 2.2 shows a comparison between the distribution of eighty (80) usable steel H-piles from
the PILOT database and the distribution of the ten (10) selected test sites by soil profiles. As
explicitly described in the LRFD report volume I (Roling et al., 2010), usable data were
identified as those pile load tests possessing sufficient information for pile resistance estimations
by means of either static or dynamic analysis methods. In recognizing a larger number of usable
steel H-piles in the sand and mixed profiles and a relatively small number in clay profile, from
the PILOT database, five preferable test pile locations with a clay profile are selected, as listed in
Table 2.1 in order to increase the total datasets for clay profile.
2.1.4. Sites with Relatively Less Dense Soil
Bridge foundations, especially those constructed at riverbanks, are commonly located in
3
Geological Regions
Alluvium
Loess
Wisconsin Glacial
Loamy Glacial
Loess on top of Glacial
ISU7
ISU 6
ISU 3
ISU 4
ISU8
ISU10
ISU1
Legend
#
ISU 2
Number of usable data
ISU 2 Test pile location for
ISU 5
ISU2 (clay profile)
ISU9
Figure 2.1. Iowa geological map and the test pile locations
4
ISU1
Test pile location for
ISU1 (mixed profile)
ISU9
Test pile location for
ISU9 (sand profile)
Mixed
26
Mixed
3
Sand
34
Clay
20
Sand
2
Clay
5
(a) Usable PILOT Database
(b) Test Pile Locations
Figure 2.2. Distribution of steel H-piles by soil profiles
relatively less dense soils in the State of Iowa. Hence, these selected test locations are designed
to most appropriately reflect the common less dense soil conditions and help in reducing any bias
in the LRFD resistance factors calibration.
2.1.5. Sites with Shallow Bedrock
Shallow bedrock is not a common soil condition in Iowa for bridge foundations. In view of the
fact that steel H-piles have relatively large perimeter and small cross sectional area, they are
widely designed and used as frictional piles in the State of Iowa. Knowing standard steel H-piles
are 60-ft (18.3-m) in length, any site with a bedrock layer less than 60-ft (18.3-m) is disregarded.
Hence, all selected sites provided in Table 2.1 have bedrock layers more than 60-ft (18.3-m).
2.1.6. Nature of Bridge Construction Projects
Despite the selected site locations meeting the above criteria, the nature of the bridge
construction projects could eventually govern the final selection. With the input from the project
technical advisory committee, unfavorable project sites are identified with the following
conditions: (1) projects have a short or constrained construction schedule; (2) projects located at
critical and major highways, such as Interstates I-35 and I-80; and (3) projects have limited space
for pile testing.
2.2. Selected Test Pile Locations
Based on the available bridge construction projects in Iowa, as designated by the Iowa DOT and
following all criteria established above, ten (10) test sites were selected. Figure 2.1 and Table
2.1 show the locations of the test sites corresponding to the geological regions and the soil
profiles. Project identifications (IDs) were assigned to the test sites, starting from ISU1 to
ISU10, and these will be used throughout the report. Table 2.1 also provides the counties where
the selected sites are situated, Iowa DOT bridge construction project numbers, closest Iowa DOT
boring log to the test pile, soil layers, SPT N-values, and bedrock depth. Based on the Iowa
DOT borehole soil information, the preliminary soil profiles were established. After completing
all detailed soil characterization, the final soil profiles were established based on the final
embedded pile lengths. The site layouts of the test pile locations are included in Appendix A.
5
Table 2.1. Information on selected steel H-pile test locations
Bedrock
Depth
Preliminary
Soil Profile
from Iowa
DOT
Boreholes
Final
Embedded
Test Pile
Length (ft)
Confirmed
Soil Profile
from ISU
Soil Tests
9 (10-ft), >50
> 60-ft
Clay
32.50
Mixed
SF:C to ST:C,F:SH,
H:SH
4 (50-ft), 12 (20ft), 22 (10-ft), >50
≈ 77-ft
Clay
55.83
Clay
F-0957
F:C, F:SH, H:SH
13 (53-ft), 37 (12ft), 55 (> 3-ft)
≈ 75-ft
Clay
51.00
Clay
Loess on
Top Glacial
P-3666
ST:SL-C, F:C, GR,
V.F:C
6 (5-ft), 7 (10-ft),
23 (20-ft), 10 (>
30-ft)
> 60-ft
Mixed
56.78
Clay
Loess on
Top Glacial
T-1592
F:C, V.F:C
10 (30-ft),
23 (> 40-ft)
> 60-ft
Clay
56.67
Clay
Loamy
Glacial
F-1049
ST:SL-C, M:S, V.F:GC
8 (11-ft), 5 (19-ft),
22 (> 30-ft)
> 60-ft
Mixed
57.2
Clay
BRF-1503(58)-38-10
Loamy
Glacial
F-1049
ST:SL-C, M:S, V.F:GC
8 (11-ft), 5 (19-ft),
22 (> 30-ft)
> 60-ft
Mixed
26.90
(10-ft
Prebore)
Mixed
BRF-0065(14)-38-79
BROSC029(56)-SF29
Loess on
Top Glacial
F-1027
F:SL-C, M:S, V.F:G-C
> 60-ft
Mixed
57.21
Mixed
Alluvium
1
F:SL-C, FN:S, F:SL-C,
FN:S
> 86-ft
Sand
49.4
Sand
Loamy
Glacial
n/a
n/a
n/a
n/a
49.5
Sand
Project
ID
County
Iowa DOT
Project
Number
ISU 1
Mahaska
BRF-633(46)-38-62
ISU 2
Mills
ISU 3
Polk
ISU 4
Jasper
ISU 5
Clarke
ISU 6
Buchanan
ISU 7
Buchanan
ISU 8
Poweshiek
ISU 9
Des Moines
ISU 10
Cedar
BRF-9781(15)-38-65
BRFIM-0.353(182)87-0577
BRF-0144(44)-38-50
BRFIMX-0351(105)33-1420
BRF-1503(58)-38-10
n/a
Geological
Region
Closest
Iowa
DOT
SPT
Borehole
Description of Soil
Layers according to
Iowa DOT Boring
Logs
SPT N-value
(Soil Layer
Thickness)
Loess on
Top Glacial
P-4010
ST:C, H:C
Loess
T-1420
Wisconsin
Glacial
8 (14.4-ft), 9 (16ft), 20 (30-ft)
11 (9-ft), 22 (45ft), 19 (7-ft), 23 (>
25-ft)
n/a
Notation for soil layer: B = Boulders, C = Clay, CR = Coarse, F = Firm, FN = Fine, G = Glacial, GR = Gravel, H = Hard, LS = Limestone, M = Medium, R = Rock, S = Sand,
SF = Soft, SH = Shale, SL = Silt, SS = Sandstone, ST = Stiff, V = Very, and W = With
6
CHAPTER 3: SITE CHARACTERIZATION
The soil profiles at all test sites were characterized using both in-situ and laboratory soil tests.
The in-situ soil investigations included Standard Penetration Tests (SPT), Cone Penetration Tests
(CPT), conventional Borehole Shear Tests (BST), and modified Borehole Shear Tests (mBST).
Five sites were selected for monitoring pore water pressure and lateral earth pressure before and
after pile driving, during re-strikes and during static load tests. The layouts of the in-situ soil
investigations are shown in Appendix A. The laboratory soil tests consisted of basic soil
characterization (i.e., gradation, Atterberg’s limits and moisture content) and consolidation tests.
A general summary of both in-situ and laboratory soil investigations are shown in Table 3.1.
Detailed descriptions of each test and the corresponding results are presented in the following
sections. For additional measured soil results, refer to Appendix B.
Table 3.1. Summary of in-situ and laboratory soil investigations
Project
ID
Standard
Penetration
Test (SPT)
Cone
Penetration
Test (CPT)
Borehole
Shear Test
(BST)
modified
Borehole
Shear Test
(mBST)
Pore Water
and Lateral
Earth Pressure
Measurement
Gradation
and
Atterberg’s
Limits Tests
Consolidation
Test
ISU 1
Not
Performed
2 Tests
1 Test
(3 depths)
Not
Performed
Not Performed
5 Tests
Not Performed
ISU 2
1 Test (9a)
1 Test (2b)
1 Test
(2 depths)
Not
Performed
Not Performed
6 Tests
3 Tests
ISU 3
1 Test (10a)
1 Test (2b)
7 Tests
3 Tests
1 Test (9a)
1 Test (4b)
Not
Performed
1 Testc
(2 depths)
Not Performed
ISU 4
1 Test
(2 depths)
1 Testc
(2 depths)
Not Performed
10 Tests
3 Tests
ISU 5
1 Test (8a)
3 Tests (1b at
Test 3)
1 Testc
(3 depths)
1 Testc
(3 depths)
2 Tests
9 Tests
3 Tests
ISU 6
ISU 7
1 Test (9a)
1 Test (4b)
1 Testc
(3 depths)
1 Testc
(3 depths)
2 Tests
1 Test
8 Tests
3 Tests
ISU 8
1 Test (12a)
1 Test (4b)
1 Testc
(3 depths)
1 Testc
(3 depths)
1 Test
10 Tests
3 Tests
ISU 9
1 Test (12a)
1 Test (2b)
Not
Performed
Not
Performed
Not Performed
9 Tests
Not Performed
ISU 10
1 Test (10a)
1 Test
Not
Performed
Not
Performed
1 Test
7 Tests
Not Performed
a
- Number of SPT N-value recorded
- Number of CPT pore water pressure dissipation tests
c
- BST or mBST with shearing displacement measurement
b
3.1. Standard Penetration Tests (SPT)
Team Services of Des Moines, Iowa, conducted all Standard Penetration Tests (SPT) at locations
shown in Appendix A. All SPT tests were performed in accordance with American Society for
Testing and Materials (ASTM) standard D1586. SPT determines the standard penetration
resistances, or the "N-values", that are used in the pile static and dynamic analyses presented in
the IHRB TR-573, TR-583 and TR-584 Report Volume III. The N-value is computed by adding
the number of 140-lb (63.5-kg) hammer blows, of a 2-in. (50-mm) diameter thick-walled splitspoon sampler, required for the second and third penetrations of 6-in. (150-mm) depth, as shown
7
in Figure 3.1. The results of the SPT N-values for ISU5 at Clarke County are presented in Figure
3.2, and similar SPT results for other sites are included in Appendix B. The N-values (NF)
obtained from the field SPT under different effective overburden pressures were corrected (Ncor)
to correspond to a standard effective vertical stress (σ′v), using Eq. 3-1 (Das 1990). The
correction factor (CN) used in this conversion, was determined using Eq. 3-2 (Liao and Whitman
1986).
Ncor = CN NF
√
σ′ (
(3-1)
)
(3-2)
As an example, the results from the ISU5’s SPT are illustrated in Figure 3.2, where at a depth of
38-ft (10-m) the field SPT N-value was 22, effective stress is 2.45 tons/ft2 (235 kPa), and a
calculated CN of 0.64, using Eq.3-2, was obtained, and the corrected SPT N-value (Ncor) is 14.
Disturbed soil samples were collected by the research team during the SPT tests for soil
gradation tests, Atterberg’s limits tests and soil classifications according to the Unified Soil
Classification System (USCS) described in Section 3.5. In addition, undisturbed soil samples
were collected using 3-in. (75-mm) Shelby tube thin-walled samplers for laboratory
consolidation tests.
(a) SPT blow count
(b) Split-spoon sampling
Figure 3.1. Typical Standard Penetration Test (SPT)
8
CPT 3 Measurements
0
0
Tip Resistance
qc (Ton/ft2)
80
Sleeve Friction
fs (Ton/ft2)
0
3
Pore Pressure
u2 (psi)
-12
8
CPT Soil
Description
Soil Behavior
Type Zone
0
12
SPT N-value
(Corrected N-value)
BST
(mBST)
Disturbed
Sample
(USCS)
grey silty clay
DS-1(SC)
6(12)
5
light brown
silty clay
10
φ = 25.05º
c = 2.17 psi
(α = 22.71º)
(a = 2.19 psi)
clay
DS-2(ML)
DS-3(CL)
8(8)
15
grey clay w/
trace sand
PC1 at
23.17 ft
DS-4(CL)
Depth (ft)
9(8)
φ = 5.43º
c = 3.79 psi
(α = 7.41º)
(a = 2.63 psi)
20
25
PC2 at
23.25 ft
silty clay
to clay
10(7)
30
clay
35
brown grey
silty clay
Based on SPT Borehole
DS-5(CL)
φ = 27.04º
c =10.53 psi
(α = 14.98º)
(a = 6.12 psi)
DS-6(CL)
Clayey sand
22(14) sandy clay
40
silty clay
to clay
20(12)
DS-7(SC)
greybrown
silty clay
DS-8(CL)
15(9)
45
Pore pressure
dissipation test
Push-in Pressure Cells
Figure 3.2. In-situ soil investigations and soil profile for ISU5 at Clarke County (CPT 3)
9
3.2. Cone Penetration Tests (CPT)
Cone Penetration Tests (CPT) were performed in accordance with ASTM Standard D5778.
Geotechnical Services, Inc. (GSI) performed all CPT tests at locations shown in Appendix A.
The CPT investigation utilized a 20-ton capacity, truck-mounted rig hydraulically advancing a
Hogentogler Type 2, 10-ton subtraction cone, as shown in Figure 3.3. The electronic peizocone
has a 60º tip angle, tip area of 1.55-in2 (10-cm2), a net area ratio of 0.8, and a friction sleeve area
of 23.25-in2 (150-cm2). During the CPT, the cone was pushed into the ground at a controlled rate
of around 1-in/s, while the uncorrected tip resistance (qc), local sleeve friction (Fs) and pore
pressure (u2) measurements were collected at every 2-in. (50-mm) interval, as presented in
Figure 3.2 for ISU5 and in Appendix B for all sites. Soil types, as shown in Figure 3.2, were
identified using a simplified soil classification chart for a standard electric friction cone adapted
from Robertson & Campanella (1983).
CPT
Piezocone
Figure 3.3. Typical Cone Penetration Test (CPT)
In addition, pore pressure dissipation tests were conducted at selected depths, as indicated in
Figure 3.2 for ISU5 and in Appendix B for other sites. The results of these pore pressure
dissipation tests were used to estimate the horizontal coefficient of consolidation (Ch) based on
the strain path method reported by Houlsby and Teh (1988) and techniques suggested by Sully
and Campanella (1994) for fine-grained soil. The pore pressure dissipation for ISU5 at 38.55-ft
(11.75-m) depth, as shown in Figure 3.4, was conducted in a relatively hard and predominately
fine-grained soil identified as silty clay to clay. Therefore, pore water pressure built up was
measured, and due to dilation of soil, a long time was needed to re-saturate the cone tip before
any pore pressure dissipation could be observed. The horizontal coefficient of consolidation (Ch)
could not be estimated. Therefore, pore pressure dissipation for ISU2 at 35.4-ft (10.79-m) depth,
as shown in Figure 3.5, is used to illustrate the calculation of Ch using Eq. 3-3 (Houlsby and Teh
1988). The rigidity index (IR) is estimated using Eq. 3-4 and Eq. 3-5 (Mayne 2001).
10
Based on the normalized pore water pressure (Bq), the effective friction angle ( ′) is calculated
either by Eq. 3-6 for granular soil where Bq < 0.1 (Kulhawy and Mayne 1990) or by using Eq.3-7
for soils where 0.1 ≤ Bq ≤ 1.0, as per an approach developed by the Norwegian University of
Science and Technology (NTNU) and discussed by Mayne (2007). By normalizing the
measured pore pressures with the maximum pore pressure of 64.18 psi and plotting this in a
logarithmic scale, starting at the maximum pore pressure, against time, the time for reaching the
50% pore pressure dissipation (t50) is estimated at 265 seconds (4.42 min) as shown in Figure
3.5. The effective friction angle ( ′) of 27.63º is estimated using Eq. 3-7 and yields the
constrained modulus parameter (M) of 1.10. Using the CPT measurements of qc, u2 and the net
area ratio of 0.8, the corrected tip resistance (qt) of 147.59 psi (1.02 MPa) and the rigidity index
(IR) of 17.47 are calculated. Finally the horizontal coefficient of consolidation (Ch) of 0.1152
in2/min (74.32 mm2/min) is calculated using Eq. 3-3. The summary of the related parameters
and Ch is presented in Table 3.2.
√
[(
(3-3)
σ
)(
)
]
φ′
φ′
(3-5)
⁄σ
(
′
σ
√ ⁄σ
(
(3-6)
)
)
where
Ch
T50
ac
IR
t50
qt
qc
σvo
u2
′
σ′vo
σatm
Bq
Q
= Horizontal coefficient of consolidation estimated using CPT results, in2/min;
= Modified time factor for Type 2 cone at 50% dissipation = 0.245;
= Tip area of cone = 1.55-in2, in2;
= Rigidity index evaluated directly from CPT data using Eq.3-4;
= Measured time to reach 50% consolidation, sec;
= Corrected tip resistance = qc+u2(1- net area ratio), psi;
= Uncorrected measured tip resistance, psi;
= Total vertical geostatic stress, psi;
= CPT measured pore pressure, psi;
= Frictional angle, degree;
= Effective vertical geostatic stress, psi;
= Atmospheric pressure = 1.47x10-5, psi;
= Normalized pore water pressure parameter = (u2-uo)/(qt-σvo); and
= Normalized cone tip resistance = (qt-σvo)/σ′vo.
11
(3-4)
(3-7)
8
7
Pore Pressure (psi)
6
5
4
3
2
1
0
0.1
1
10
100
Time (second)
1000
10000
Figure 3.4. Increase in pore pressure for ISU5 at a depth of 38.55-ft
70
1.1
1
60
Normalized Pore Pressure
0.9
Pore Pressure (psi)
50
40
30
20
0.8
0.7
0.6
0.5
0.4
0.3
0.2
10
0.1
0
0
0.1
10
Time (sec)
1000
0.1
265
10
Time (sec)
1000
Figure 3.5. Pore pressure dissipation result for ISU2 at a depth of 35.4-ft
12
Table 3.2. Summary of soil parameters at depths of CPT dissipation tests
Project
ID
ISU2
ISU3
ISU4
ISU6
ISU8
Depth (ft)
t50 (min)
35.40
22.15
19.50
21.00
41.00
50.53
50.03
57.25
4.42
31.27
43.42
64.78
227.99
88.68
151.52
264.83
′
(degree)
27.72
11.94
24.66
38.71
21.80
33.09
30.28
34.24
M
qt (psi)
u2 (psi)
σvo (psi)
IR
1.10
0.44
0.97
1.58
0.85
1.33
1.21
1.39
147.59
228.47
239.71
1209.92
353.17
313.15
282.47
732.76
57.40
38.20
4.13
5.19
37.41
82.21
9.60
4.08
18.24
17.31
12.54
14.45
25.01
29.82
35.42
34.42
25.13
58.37
4.01
2.51
7.06
7.71
2.33
2.50
Ch
(in2/min)
0.1382
0.0298
0.0056
0.0030
0.0014
0.0038
0.0012
0.0007
The CPT soundings provide a nearly continuous subsurface soil profile and are used to estimate
basic soil parameters such as effective friction angle ( ′) as explained above, undrained shear
strength (Su), and over-consolidation ratio (OCR). The undrained shear strength (Su) is estimated
using a classical approach given by Eq. 3-8 (Mayne 2007). The over-consolidation ratio (OCR)
for intact clays is estimated using Eq. 3-9 (Demers and Leroueil 2002). These estimated soil
parameters are used in the static and dynamic pile analyses conducted later. The average soil
parameters are summarized in Table 3.3 for ISU5 based on the CPT classified soil profiles,
indicated in Figure 3.2, and are summarized in Appendix B for all sites.
σ
(3-8)
(3-9)
where
Nkt
= Bearing factor; 15 was assumed for representing the Iowa soil condition; and
Table 3.3. Summary of soil properties for ISU5 based on CPT
Soil Profiles
Depth (ft)
Soil Types
Layer 1
0 to 25
Layer 2
25 to 29
Layer 3
29 to 39
Layer 4
39 to 45
Clay
Silty Clay to
Clay
Clay
Silty Clay to
Clay
Average Effective
Friction Angle, ′
(degree)
31.08
Average
Undrained Shear
Strength, Su (psi)
13.28
Average Overconsolidation
Ratio (OCR)
5.60
29.94
15.71
3.11
29.72
16.46
2.63
32.09
30.61
3.92
13
3.3. Borehole Shear Tests (BST)
Borehole shear tests (BST) were conducted at each test site, except ISU9 and ISU10, by the
research team. BST equipment, as shown in Figure 3.6, was developed by Emeritus Professor
Richard Handy of Iowa State University to rapidly and directly measure the in-situ effective
shear strengths of soil in relation to applied normal pressure. A 3-in (75-mm) smooth hole was
drilled to a desired depth. An expandable shear head with a pair of grooved shear plates was
inserted into the hole and pushed against the sides of the hole with a predetermined normal
pressure, starting from the top soil layer to minimize hole disturbance. After allowing time for
soil consolidation, the shear head was slowly pulled upward to measure the shear stress (τ).
Furthermore, the shear stress increments were continuously recorded at every 10 rotations of the
crank, which was equivalent to 0.006-in. (0.152-mm) of the vertical shearing displacement.
Repeating this process with increasing the normal stress (σ), a Mohr-Coulomb shear failure
envelope, as shown in Figure 3.7 for ISU5 at 8.83-ft (2.69-m) depth, was generated based on the
maximum shear stresses and the corresponding applied normal stresses, in order to determine the
soil frictional angle ( ) and cohesion (c). The soil friction angle ( ) of 25.08º is the arctangent
of the shear envelope slope of 0.47, and the soil cohesion is the vertical axis interception of 2.17
psi (14.96 KPa). The shear stress-displacement relationship at each applied normal stress is
plotted in Figure 3.8. The results of BSTs for all sites are presented in Appendix B.
3 in. augur
3 in.
Grooved
shear plate
(a) Cross sectional view
(b) Photo view
Figure 3.6. The conventional Borehole Shear Test (BST) equipment (adapted from Handy,
1986)
14
7
τ = 0.4678σ + 2.1711
φ = 25.08⁰; c = 2.17 psi (BST)
Shear Stress, τ (psi)
6
5
4
3
2
1
0
0
2
4
6
8
10
Normal Stress, σ (psi)
Figure 3.7. BST generated Mohr-Coulomb shear failure envelope for ISU5 at 8.83-ft depth
7
6
Shear Stress (psi)
5
4
3
2
BST (σ = 3.19 psi)
BST (σ = 4.35 psi)
1
BST (σ = 5.80 psi)
BST (σ = 8.70 psi)
0
0
50
100
150
200
250
-3
Shear Displacement (in x 10 )
300
350
Figure 3.8. BST generated shear stress-displacement relationship at different applied
normal stress for ISU5 at 8.83-ft depth
15
3.4. Modified Borehole Shear Tests (mBST)
Similar to conventional Borehole Shear Test (BST), the modified Borehole Shear Test (mBST)
was performed using a pair of smoothed steel plates as shown in Figure 3.9 instead of using the
BST’s grooved steel plates. The modified Borehole Shear Test equipment was explicitly
described by AbdelSalam et al. (2010). The mBST directly determines the frictional angle (α)
and adhesion (a) between the smoothed steel plate and the contacted soil by measuring the shear
displacement and the corresponding shear stresses (τ) at several applied normal stresses (σ).
Figure 3.10 shows the relationships between the shear stresses and the shear displacements at
four different applied normal stresses for ISU5 at 8.83-ft (2.69-m) depth. Taking the peak shear
stress at each applied normal stress, the Mohr-Coulomb shear failure envelope was generated as
shown in Figure 3.11. The interface frictional angle (α), between the steel plate and soil, of
20.75º is the arctangent of the envelope slope of 0.38, and the interface adhesion (a) is the
vertical axis interception of 2.48 psi (17.10 KPa).
3 in. augur
3 in.
Smoothed
shear plate
(a) Cross sectional view
(b) Photo view
Figure 3.9. The modified Borehole Shear Test (mBST) equipment (adapted from Handy,
1986)
16
7
6
Shear Stress (psi)
5
4
3
2
mBST (σ = 3.19 psi)
mBST (σ = 4.35 psi)
1
mBST (σ = 5.80 psi)
mBST (σ = 8.70 psi)
0
0
50
100
150
Shear Displacement (in × 10-3)
200
250
Figure 3.10. mBST generated shear stress-displacement relationship at different applied
normal stress for ISU5 at 8.83-ft depth
7
Shear Shear, τ (psi)
6
5
4
τ = 0.3787σ + 2.4808
α = 20.75⁰; a = 2.48 psi (mBST)
3
2
1
0
0
2
4
6
8
10
Normal Stress, σ (psi)
Figure 3.11. mBST generated Mohr-Coulomb interface shear failure envelop for ISU5 at
8.83 ft depth
17
3.5. Laboratory Soil Tests
3.5.1 Soil Grain Size Distribution
Disturbed samples collected from SPT boreholes at various depths were used in a soil gradation
test in accordance with ASTM D6913 using sieve analysis, as shown in Figure 3.12 (a), for soil
particle sizes greater than 0.0029-in (0.074-mm or No. 200 sieve). A hydrometer 151H that
complied with ASTM E100, illustrated in Figure 3.12 (b), was used in accordance with ASTM
D422 to determine the grain size distribution finer than 0.0029-in (0.074-mm). Combining the
results obtained from the sieve analysis and the hydrometer test, a complete grain size
distribution curve was generated, as shown in Figure 3.13, for the disturbed sample DS-1
collected at 3-ft (0.9-m) depth of ISU5. The particle sizes finer than 10%, 30% and 60%,
denoted as D10, D30, and D60 respectively, for ISU5 were determined from the grain size
distribution curve shown in Figure 3.13 and listed in Table 3.4.
(a) Sieve analysis
(b) Hydrometer test
(c) Atterberg’s limit test
Figure 3.12. Laboratory soil tests
3.5.2. Atterberg Limits
In addition to performing the above soil gradation tests, Atterberg’s limit tests were conducted in
accordance with ASTM D4318, using equipment as shown in Figure 3.12 (c), to determine the
plastic limit (PL) and liquid limit (LL). These Atterberg’s limits are essential properties for
classifying fine-grained soil. The plastic limit (PL) is the amount of moisture content in a soil
when it starts to exhibit plastic behavior. It is determined when a thread of soil, rolled to a
diameter of 0.12-in (3-mm), begins to crumble. The liquid limit (LL) is defined as the amount of
moisture content in a soil when it changes from plastic to liquid behavior. The liquid limit is
determined by placing the soil sample into the metal cup of the LL device, as shown in Figure
3.12 (c), and making a 0.5-in. (13-mm) groove down its center with a standardized tool. The
number of blows required to close the groove is recorded and the moisture content at which it
took 25 drops of the cup is defined as the liquid limit. The difference between the liquid limits
and the plastic limits are defined as the plasticity indices (PI), which are listed in Table 3.4 for
ISU5.
18
Particle Diameter (in) - Log Scale
3.94E-01
3.94E-02
3.94E-03
3.94E-04
3.94E-05
100
90
90
80
80
70
70
60
60
50
50
40
40
30
30
20
20
10
10
0
100
10
1
0.1
0.01
0.001
Percent Finer (%)
Percent Finer (%)
3.94E+00
100
0
0.0001
Particle Diameter (mm) - Log Scale
Figure 3.13. Grain size distribution curve for disturbed sample DS-1 at 3 ft depth of ISU5
3.5.3. Soil Classification
After performing the above soil gradation tests and Atterberg’s limit tests and determining the
essential soil properties, the soil was classified using the Unified Soil Classification System
(USCS) in accordance with ASTM D2487. The results of the USCS soil classification are listed
in Table 3.4 for ISU5 and are included in Appendix B for other sites. Estimated values for the
natural moisture content (ω), void ratio (e), and saturated unit weight (γsat) properties of the soils
tests are also included in Table 3.4 for ISU5 and in Appendix B. The natural moisture content
(ω) is determined in accordance with ASTM D2216 and estimated using Eq. 3-10. The void
ratio (e) is estimated using Eq. 3-11 by assuming 100% saturation (S) and a specific gravity (G)
of 2.7. Using the estimated void ratio, the saturated unit weight (γsat) is estimated using Eq. 3-12.
ω
(3-10)
(3-11)
19
(
)
(3-12)
where
ω
Ww
Ws
e
G
S
γw
γsat
= Moisture content, %;
= Weight of moisture (water) in a soil sample, lb;
= Weight of solid in a soil sample, lb;
= Void ratio;
= Specific gravity (assumed 2.7);
= Degree of saturation (assumed 100%), %;
= Unit weight of water = 62.4 pcf; and
= Saturated unit weight, pcf.
Table 3.4. Soil classification and properties for ISU5 obtained from gradation and
Atterberg’s limit tests
Distur
bed
Sample
Sample
Depth (ft)
Soil
Type
(USCS)
D10
(in)
D30
(in)
D60
(in)
Liquid
Limit,
LL (%)
Plasticity
Index, PI
(%)
Moisture
Content,
ω (%)
Saturated
Unit
Weight,
γsat (pcf)
Void
Ratio,
e
DS-1
3
SC
3.3E-5
8.1E-4
2.1E-2
26.31
11.27
20.39
130.82
0.55
DS-2
8 to 10
ML
9.0E-6
4.8E-4
2.7E-3
36.30
5.57
18.70
132.89
0.50
DS-3
10 to 12
CL
-
2.4E-4
2.6E-3
38.41
20.82
20.64
130.52
0.56
DS-4
16
CL
-
3.4E-4
2.7E-3
49.10
27.08
21.58
129.42
0.58
DS-5
28 to 30
CL
-
3.4E-4
2.8E-3
44.60
26.84
17.20
134.84
0.46
DS-6
37 to 38.5
CL
-
3.4E-4
2.7E-3
38.61
22.23
22.03
128.92
0.59
DS-7
38.5 to 40
SC
-
7.2E-4
6.4E-3
22.02
8.63
19.80
131.52
0.53
DS-8
43.5 to 45
CL
-
1.2E-4
2.6E-3
38.73
20.78
16.11
136.32
0.44
DS-9
48 to 50
CL
-
1E-4
2.4E-3
40.07
22.33
16.94
135.19
0.46
D10, D20, and D60 ‒ particle sizes finer than 10%, 30% and 60%, respectively.
3.5.4. Laboratory Soil Consolidation Tests
The undisturbed samples collected in the 3-in. (75-mm) Shelby tubes from the SPT boreholes
were extruded, trimmed and inserted into a consolidation ring for laboratory soil consolidation
tests, performed in accordance with ASTM D2435. The consolidation ring, weighted at about
0.14 lb (65 g), has an inner diameter (D) around 2.51-in. (63.7-mm) and a height (Ho) of 0.79-in.
(20.1-mm). The consolidation loading device and the consolidometer are shown in Figure 3.14.
20
(b) Consolidometer
(a) Consolidation loading equipment
Figure 3.14. Laboratory soil consolidation tests
Test method A (described in ASTM D2435) was performed with a constant load increment
duration of at least 24 hrs. Soil specimen deformations at applied loading and unloading
increments were measured at specified time intervals as indicated in the ASTM D2435. Doublesided drainage was allowed during all consolidation tests. The loading increments were 0.87 psi,
1.74 psi, 3.63 psi, 7.25 psi, 14.50 psi, 29.01 psi, 58.02 psi, 116.03 psi, and 232.06 psi. The
unloading increments started from 232.06 psi to 116.03 psi, 29.01 psi, 7.25 psi, and 1.74 psi.
The natural initial moisture contents (ω) of the soil samples were determined in accordance with
ASTM D2216 and computed using Eq. 3-10. Assuming the specific gravity (G) of the soil to be
2.7 and having measured the dry soil mass in the consolidation ring (Ms), the initial height of the
solid component of each soil specimen (Hs) is estimated using Eq. 3-13, where the water density
(ρw) is taken as 0.036 pci (1 g/cm3). Using the estimated initial solid height (Hs), the initial void
ratio (eo) of each soil specimen is calculated using Eq. 3-14. These initial soil properties are
listed in Table 3.5.
ρ
( )
(3-13)
(3-14)
21
Based on the soil deformation measurement at each load increment, the void ratio (e) at each
applied pressure (σ) is calculated using Eq. 3-15 and is plotted with the corresponding applied
pressure in a logarithmic scale. Using the e-Log (σ) curve generated in Figure 3.15 for sample
Clarke-25, the pre-consolidation stress (σc) is estimated using the Casagrande’s Method as
described in ASTM D2435. The over-consolidation ratio (OCR) is determined from the test
using Eq. 3-16, which gives a ratio of the pre-consolidation stress (σc) and the total vertical
effective stress (σ′v). Besides calculating the over-consolidation ratio, the coefficient of
consolidation (Cv) at each applied loading pressure is calculated using Eq. 3-17 based on
Taylor’s Square Root Time (√ ) Method. The dimensionless time factor (T90) for 90%
consolidation was determined to be 0.848. The length of the drainage path for double-sided
drainage (Hdr) was taken as half of the average specimen height at the applied loading increment.
The time corresponding to the 90% consolidation (t90) is estimated using the Taylor’s Square
Root Time (√ ) Method. The results of the consolidation tests are summarized in Table 3.5.
(3-15)
(3-16)
(
6.9E-01
0.80
6.9E+00
Log σ (kPa)
6.9E+01
)
6.9E+02
(3-17)
6.9E+03
-2.7%
Initial Void Ratio, eo= 0.72
0.70
2.3%
7.3%
0.50
12.3%
0.40
0.30
17.3%
0.20
22.3%
σc = 30 psi
σ′v = 23.35 psi
OCR = 1.28
0.10
27.3%
0.00
0.1
Strain, ε (%)
Void Ratio, e
0.60
1
σ = 30 psi
10 c
Log σ (psi)
100
1000
Figure 3.15. The e-log(σ) curve for evaluating pre-consolidation stress from Casagrande’s
Method for specimen Clarke-25
22
Table 3.5. Summary of the consolidation test results and analyses
Project
ID
Sample Depth in
feet
Initial
Moisture
Content,
ω (%)
Initial
Solid
Height,
Hs (in)
Mills-9
19.00
0.52
Mills-20
30.31
0.43
ISU2
Mills-30
25.69
0.43
Mills-55
36.94
0.39
Polk-3
15.65
0.59
ISU3
Polk-27
27.18
0.49
Polk-50
29.06
0.48
Jas-15
13.10
0.59
Jas-27
17.12
0.53
ISU4
Jas-45
15.09
0.57
Jas-60
15.41
0.56
Clarke-8
21.82
0.48
ISU5
Clarke-25
25.91
0.46
Clarke-35
15.13
0.56
Buc-12
32.26
0.42
ISU6 and
Buc-49
13.56
0.57
ISU7
Buc-59
15.07
0.56
Pow-3
23.19
0.49
ISU8
Pow-23
24.87
0.42
Pow-44
16.72
0.54
a
– round up to 1.00 for normally consolidated soils.
Initial
Void
Ratio, eo
Preconsolidation
Stress, σc
(psi)
Effective
Vertical
Stress,
σ′v (psi)
Over
Consolidation
Ratio, OCR
Coefficient of
Consolidation
at σ’v, Cv at
(in2/min)
0.54
0.84
0.86
1.01
0.33
0.62
0.67
0.33
0.49
0.40
0.42
0.64
0.72
0.40
0.86
0.39
0.40
0.62
0.86
0.46
6.3
20
30
34
13
28
35
26
30
23
36
33
30
17
16
38
34
10
13.3
13
7.92
17.53
28.56
38.77
2.77
18.37
26.86
10.5
18.40
27.07
34.95
7.42
23.35
31.29
13.31
34.83
37.06
2.26
18.37
28.66
1.00a
1.14
1.05
1.00a
4.69
1.52
1.30
2.48
1.63
1.00a
1.03
4.45
1.28
1.00a
1.20
1.09
1.00a
4.43
1.00a
1.00a
0.023
0.008
0.020
0.018
0.011
0.012
0.006
0.019
0.012
0.012
0.007
0.017
0.014
0.008
0.005
0.006
0.009
0.020
0.030
0.011
3.6. Pore Water and Lateral Earth Pressure Measurements
The in-situ pore water and total lateral earth pressures were measured using Geokon Model 4830
push-in pressure cells shown in Figure 3.16. As listed in Table 3.1, the push-in pressure cells
were installed at ISU5, ISU6, ISU7, ISU8 and ISU10, and the locations are indicated with solid
black crosses on the site layout plans in Appendix A. The push-in pressure cells were installed
in a range of approximately 8-in. (200-mm) to 24-in. (600-mm) away from one of the flanges of
a test pile. The elevations of the pressure cells are indicated on the soil profile as shown in
Figure 3.2 for ISU5 and in Appendix B for ISU6, ISU7, ISU8, and ISU10. The pressure cell is
fitted with an integral piezometer on one of the flat surfaces to measure pore water pressure.
Before installing the pressure cell, the piezometer was saturated with water by drawing a vacuum
on the circular porous sensor and allowing water to flow into the sensor when the vacuum was
released, as shown in Figure 3.16. A thread is provided on the end of the cell to allow for
installation using the SPT drill rods.
During the installation, the pressure cell was oriented, so that the circular porous sensor and the
flat surface faced the proposed position of the flange of the test pile. The pressure cell was then
slowly lowered into the ground through the SPT auger which had been drilled to the desired
elevation. When the pressure cell reached the bottom of the drilled hole, it was pushed into the
ground for about 14-in. (350-mm). The process of pushing the pressure cell created an increase
in temperature, pore water and earth pressures surrounding the cell, therefore the cell was
required to stabilize for at least 24 hours to reach both thermal and pressure equilibriums before
taking any measurement as recommended by Suleiman et al. (2010) in Iowa soils. Readings were
then taken at every 4 seconds during pile driving, re-strikes and static load test. However,
23
readings were taken only every 30 minutes between each re-strike event and between the last restrike event and the static load test.
Temperature (T), pore water pressure and total lateral earth pressure are measured by the
pressure cells. Initially, the pressure signals and temperature signal are transmitted from the
pressure cell to a CR1000 data logger which stored data for the duration of testing, from the
beginning of a pile driving to the end of a static load test. A data analysis program known as
PC400 is used to collect the data from the data logger and to convert the data signals (Ri) into the
actual pressures (P) using the polynomial pressure Eq. 3-18. Temperature (T) is part of the
polynomial pressure equation for converting the pressure signals (Ri).
(a) Saturating pressure cells
(b) Installing pressure cells
(c) Stabilization and data acquisition system
(d) Measuring pore water pressure and lateral
earth pressure
Figure 3.16. Measurement of pore water and lateral earth pressures using Geokon push-in
pressure cells at the field
Each pressure cell is initially calibrated at Geokon’s factory to determine the gage factors (A, B,
and C), the thermal factor (κ) and the zero reading temperature (To). The calibrated factors and
24
To for each pressure cell used in the field are tabulated in Table 3.6. The pressure cells are
differentiated and identified based on coil numbers, for example, cell No.1 consists of Coil 1 and
Coil 1A, which are used to measure the total earth pressure signal and pore water pressure signal
respectively.
)
κ(
(3-18)
Table 3.6. Calibrated factors and zero reading temperature for each pressure cell
Pressure
Cells ID
Test Piles
Coil 1
ISU5, ISU7
Linear
Gage
Factor, G
(psi/digit)
0.00644
Coil 1A
ISU5, ISU7
Coil 2
Gage
Factor, A
Gage
Factor, B
Gage
Factor,
C
Thermal
Factor, κ
(psi/ºC)
Zero Reading
Temperature,
To (ºC)
-2.70E-8
-6.01E-3
61.43
2.41E-4
24.7
0.00662
-2.28E-8
-6.27E-3
62.08
9.63E-4
24.7
ISU5
0.00644
-3.05E-8
-6.17E-3
61.54
3.10E-3
24.5
Coil 2A
ISU5
0.00618
-2.45E-8
-5.99E-3
59.63
2.12E-4
24.5
Coil 3
ISU6
0.03833
-1.56E-7
-3.62E-2
329.65
1.39E-2
22
Coil 3A
ISU6
0.04152
-1.76E-7
-3.90E-2
357.88
2.38E-2
22
Coil 4
ISU6, ISU8
0.04081
-1.58E-7
-3.86E-2
353.75
6.46E-3
22
Coil 4A
ISU6, ISU8
0.04155
-1.99E-7
-3.88E-2
352.98
2.38E-2
22
After converting all signals, the actual in-situ total earth pressure and pore water pressure are
plotted as a function of time, as shown in Figure 3.17 for pressure cell (PC) No.1 at
approximately 23.17-ft (7.1-m) below ground with the groundwater table at 36-ft (11-m) and 8in. (200-mm) away from the flange of the test pile ISU5. The time plotted is relative to the time
at the end of driving. The events of pile driving, re-strikes and static load test are indicated on
the plots to illustrate the effect of the events on the measured pressures. Although the PC1 was
installed above the groundwater table, it was observed that the lateral earth pressure and the pore
water pressure increased abruptly at the moment the driven pile toe reached the elevation of the
PC1. The pore water pressure dissipated immediately when the pile toe was driven beyond the
pressure cell. The pore pressure reached equilibrium and decreased gradually over time. In
contrast, the lateral earth pressure increased gradually over time. The event of re-strikes
increased the pore water pressure slightly which dissipated almost immediately and had no effect
on the lateral earth pressure. The static load test had little or no effect on the measurements.
Unlike PC1 at ISU5, the pore water pressures at ISU6 using PC3 and PC4 were recorded at 33-ft
(10-m) below ground surface, with the groundwater table at 15-ft (4.6-m), as plotted in Figure
3.18 as function of time. Figure 3.18(a) shows the recorded data for the first 20-minute period.
Accordingly, pore water pressure recorded using PC3 experienced a slight reduction in readings
before the pile toe reached the depth of the device, but no significant change was recorded as the
pile passed by the gauge location during driving. The recorded pore pressure progressively
increased from 12 psi (84-kPa) to 14.6 psi (101-kPa) at PC3 and from 8 psi (55-kPa) to 9.3 psi
(64-kPa) at PC4 between the time when the pile passed through the devices and BOR3. After
BOR3, fluctuations in data during re-strike and static load test, as well as gradual dissipation of
pressure with time, were generally seen (Figure 3.18(b)). For PC3, which was closer to the pile,
the pore water pressure dissipation generally followed a logarithmic trend and reached a value of
about 10 psi (68-kPa) within a day (i.e., around BOR5), almost returning to its hydrostatic state,
which indicates complete dissipation in about seven days (i.e., around BOR7). Similarly, the
25
lateral earth pressure reduced over time. Overall, the restrikes and static load test had little effect
on the measurements. The results of ISU7, ISU8, and ISU10 are included in Appendix B.
40
BOR 2
40
30
30
20
20
Geostatic Vertical
Pressure, σv
10
10
Hydrostatic Pressure, μ
0
-45
-35
Pore Water Pressure (psi)
50
50
BOR 1
60
Earth Pressure (PC1)
Water Pressure (PC1)
EOD
70
Pile Driving Begin
Total Lateral Earth Pressure (psi)
80
60
Pile Reaches
PC
90
0
-25
-15
-5
5
Time After the End of Driving (Minute)
15
25
(a) Measured pressure versus time in minutes
90
Peak Pressures
EP (PC1): 70 psi
WP (PC1): 50 psi
40
40
SLT End
BOR 6
BOR 5
50
BOR 4
60
30
30
20
20
Geostatic Vertical
Pore Water Pressure (psi)
50
SLT Begin
70
BOR 3
Total Lateral Earth Pressure (psi)
80
60
Earth Pressure (PC1)
Water Pressure (PC1)
10
10
Hydrostatic Pressure, μ
(b)
0
-2
-1
0
1
2
3
4
5
6
Time After the End of Driving (Day)
7
0
8
9
10
(b) Measured pressure versus time in days
Figure 3.17. Total lateral earth pressure and pore water pressure measurements from PC1
at test pile ISU5 with respect to the time
26
120
110
100
14
12
90
10
80
Hydrostatic Pressure, μ
70
8
60
50
6
0
-20
4
BOR3
BOR2
10
BOR1
20
Geostatic Vertical Pressure, σv
EOD
30
Pile Reaches PC
40
2
0
-10
0
10
Time After the End of Driving (Minute)
Total Laterla Earth and Pore Water Pressure
(psi)
16
Earth Pressure (PC3)
Earth Pressure (PC4)
Water Pressure (PC3)
Water Pressure (PC4)
Pile Driving
Begin
Total Lateral Esrth and Pore Water Pressure
(psi)
130
20
(a) Measured pressure versus time in minutes
130
120
Peak Pressures
EP (PC3): 94 psi
WP (PC3): 15 psi
EP (PC4): 93 psi
WP (PC4): 10 psi
110
14
12
90
10
Hydrostatic Pressure, μ
70
8
60
50
6
40
4
30
SLT Begin
SLT End
BOR8
BOR6
BOR5
10
BOR7
Geostatic Vertical Pressure, σv
20
0
-2
0
2
4
6
8
10
Time After the End of Driving (Day)
12
14
2
Pore Water Pressure (psi)
80
BOR4
Total Lateral Esrth Pressure (psi)
100
16
Earth Pressure (PC3)
Earth Pressure (PC4)
Water Pressure (PC3)
Water Pressure (PC4)
0
16
(b) Measured pressure versus time in days
Figure 3.18. Total lateral earth pressure and pore water pressure measurements from PC3
and PC4 at test pile ISU6 with respect to the time
27
CHAPTER 4: FULL-SCALE TESTS
4.1. Pile Type and Properties
A recent survey completed by AbdelSalam et al. (2008) indicates that the steel H-pile foundation
is the most common bridge foundation used in the United States, especially in the Midwest. The
Iowa Department of Transportation (Iowa DOT) conducted a total of 264 static pile load tests,
between 1966 and 1989, to improve their pile foundation design practice. Of these tests, Roling
et al. (2010) summarized that 164 (62 percent) of the tests were performed on steel H-piles, and
32 of these 164 contained sufficient pile, soil, hammer and driving information to be considered
“usable data sets” for resistance factor calculations using the Wave Equation Analysis Program
(WEAP) and dynamic formulas. Of the 32 usable steel H-piles, 29 were HP 10 x 42 steel piles
(10-in. pile size and 42 lb/ft), 2 were HP 12 x 53 steel piles and one was HP 14 x 89 steel pile.
Thus, HP 10 x 42 was used in the field tests except ISU1 at Mahaska County, where HP 10 x 57
steel pile was used. ASTM A572 Grade 50 steel with a yield strength (Fy) of 50 ksi (345 MPa)
was selected and the relevant properties are listed in Table 4.1. The cross sectional view of the
steel H-piles is shown in Figure 4.1. The pile impedance (Z) is determined using Eq. 4-1, where
the elastic modulus (E) of 30,000 ksi (206,843 MPa) is used and the compressive wave speed (C)
for steel piles is taken as 16,808 ft/s (5,123 m/s).
Z
EA
C
(4-1)
The American Association of State Highway and Transportation Officials (AASHTO) (2007)
LRFD Bridge Design Specifications limit the pile stress to 0.6 Fy and 0.5 Fy under good driving
and severe driving conditions respectively. Vande Voort (2008) noted that the stress limits
reflect geotechnical concerns rather than structural limit states. In particular, the Iowa DOT
LRFD Design Manual Section 6.2.6.1 specifies allowable pile stresses of 6 ksi (41 MPa), 9 ksi
(62 MPa) and 12 ksi (83 MPa) for pile resistance levels 1, 2 and 3 respectively to limit and
control pile settlement.
Table 4.1. A572 Grade 50 (Fy = 50 ksi) steel H-pile properties
Project ID
Pile
Types
Cross
Sectional
Area, A
(in2)
Coating
Area
(ft2/ft)
Depth,
d (in)
Flange
Width, b
(in)
Flange
Thicknes,
tf (in)
Web
Thickness,
tw (in)
Pile
Impedance,
Z (kip-s/ft)
ISU1
HP 10 x
57
16.8
4.91
9.99
10.225
0.565
0.565
29.99
HP 10 x
42
12.4
4.83
9.70
10.075
0.420
0.415
22.13
15.5
5.82
11.78
12.045
0.435
0.435
27.67
26.1
7.02
13.83
14.695
0.615
0.615
46.59
ISU2 to
ISU10 and
Iowa DOT
Database
Iowa DOT
Database
Iowa DOT
Database
HP 12 x
53
HP 14 x
89
28
Figure 4.1. Cross sectional view of the steel H-piles
4.2. Hammer Types
Hammers are used for pile driving and re-strikes, with the hammer properties required for pile
resistance estimations using dynamic analysis methods and dynamic formulas. Diesel hammers
and external combustion hammers are the two main hammer types used in the State of Iowa.
The hammer information of the Iowa DOT Pile Load Test Database (PILOT) was summarized
by Roling et al. (2010). The hammer information of the field tests are summarized in Table 4.2.
The hammers used in the field tests were Delmag manufactured open end diesel hammers, which
operate on a two stroke engine cycle as shown in Figure 4.2. Delmag diesel hammers are single
acting free fall hammers utilizing the principle of impact atomization (Delmag 2005). The
driving mechanism of the hammers was described by Pile Dynamics, Inc. (2005). Some energy
loss is incurred during the driving mechanism before the energy is transmitted to piles, thus an
efficiency of 0.8 was determined by Pile Dynamics, Inc. (2005) for diesel hammers. Table 4.2
lists the weights of the hammer ram, cap and anvil, and the rated hammer energy, which were
supplied by the piling contractors. The equivalent maximum hammer stroke is defined as the
maximum height at which the hammer ram will rise or travel upwards resulting from the pile
rebound and combustion pressure. The equivalent maximum hammer stroke is calculated by
dividing the rated hammer energy with the ram weight.
Table 4.2. Summary of hammer information
Project
ID
ISU1
ISU2
ISU3
ISU4
ISU5
ISU6 &
ISU7
ISU8
ISU9
ISU10
Hammer Types
Ram
Weight
(lb)
Cap
Weight
(lb)
Anvil
Weight
(lb)
Delmag D19-42
Delmag D19-42
Delmag D19-32
Delmag D19-42
Delmag D16-32
4000
4015
4000
4015
3520
2000
1920
2000
2000
2050
753
753
753
750
810
Equivalent
Max
Hammer
Stroke (ft)
10.81
10.77
10.61
10.81
11.42
Delmag D19-42
4190
2000
750
Delmag D19-42
APE D19-42
APE D19-42
4015
4189
4189
2000
1345
1345
750
749
749
29
Efficiency
Rated Hammer
Energy (kip-ft)
0.8
0.8
0.8
0.8
0.8
43.24
43.23
42.44
43.24
40.20
10.21
0.8
42.80
10.81
11.25
11.25
0.8
0.8
0.8
43.24
47.34
47.34
Ram
Cylinder
Exhaust Port
Anvil
Recoil Dampener
Striker Plate
Hammer Cushion
Cap
Figure 4.2. Single acting open end diesel hammer (adapted from Pile Dynamics, Inc., 2005)
4.3. Strain Gauge Instrumentation
Given the focus on vertical load testing, test piles were instrumented with strain gauges in pairs
on each side of the webs at the neutral axis depth along the pile length as shown in Figure 4.3
and Figure 4.6. A combination of normal foil gauges and weldable gauges were used. The
vertical distance between gauges varied along the pile length. The locations of the strain gauges
were decided based on both the pile embedded length and the location of soil layer boundaries.
Gauges were placed within 12-in (300-mm) above and below soil layer boundaries, and the
distance between the pile toe and the nearest strain gauge was between 6-in (150-mm) to 12-in
(300-mm).
The normal strain gauges were adhered onto the steel surfaces after being cleaned with acetone.
M-coat was applied on the gauges for water resistance and flexible membranes were placed on
top of the gauges for vibration protection. Subsequently, aluminum tapes were used to cover the
gauges and the rubbers, and aluminum foil was wrapped around the cables, to prevent damage
caused by welding sparks & heat. The strain gauges and cables were placed in a vertical line
along the pile length, and the cables were tied to nuts welded to steel piles to prevent loosening
during pile handling and driving. After completing the above steps, the gauges and cables were
protected by 2-in x 2-in x 3/16 in thick (50-mm x 50-mm x 5-mm) angle bars welded on the steel
pile webs (see Figure 4.3 and Figure 4.4) to prevent damage caused by welding sparks & heat, as
well as direct soil contact during pile installation. The angle bars were welded with a continuous
6-in (150-mm) fillet weld at an interval of 24-in (600-mm). The angle bars at the pile toe were
chamfered to form a pointed end as shown in Figure 4.5. Similar procedures were applied to the
weldable gauges, except tack welding was used to adhere them to the steel piles. The strain
gauge arrangements, along with soil profiles for other test piles, are included in Appendix C.
30
Cable
Protected
Strain Gauge
6” length weld
@ 24” interval
L 2”x2”x 163 ”
6” length weld
@ 24” interval
Figure 4.3. Strain gauges arrangement at a cross sectional view of a steel H-pile
Cable Tied
to Nut
Acetone
Normal
Gauge
Adhesive
Rubber
Cable
Wrapped
with
AL Foil
Angle
Weldable
Gauge
Covered
w/ AL
Tape
(a) Strain gauge
(b) Strain gauge
(c) Covered by angles
installation
protection
Figure 4.4. Strain gauges installation, protection, and covered by angles
Pointed End at Pile Toe
Figure 4.5. Angle bars were chamfered to form a pointed end at pile toe
31
Pile head
PDA Accelerometer
and Transducers
Ground
CLK-5-60-E (32' from pile head)
CLK-5-60-W
Clay
CLK-1-30-E
(4' from pile head)
CLK-1-30-W
Steel Angle Bar
3
(L 2 x 2 x 16
)
Clay
CLK-6-60-E (39' from pile head)
CLK-6-60-W
CLK-2-30-E (11' from pile head)
CLK-2-30-W
Normal Strain
Gauge
Cable
CLK-7-60-E
(46' from pile head)
CLK-7-60-W
Silty Clay
to Clay
CLK-3-30-E
(18' from pile head)
CLK-3-30-W
Steel Angle Bar
3 ''
(L 2''x2''x16
)
CLK-8-80-E
(53' from pile head)
CLK-8-80-W
Steel H-Pile
HP10x42
Silty Clay
to Clay
CLK-9-80-E (56' from pile head)
CLK-9-80-W
CLK-4-60-E (25' from pile head)
CLK-4-60-W
Clay
CLK-10-80-E (59' from pile head)
CLK-10-80-W
Pile toe
Figure 4.6. Location of strain gauges along the ISU5 test pile at Clarke County
32
4.4. Pile Driving Analyzer (PDA) Tests
Pile Driving Analyzer (PDA) tests were conducted in accordance with ASTM D4945 to
investigate the development of soil resistances as a function of time, evaluate pile data quality,
estimate pile resistance, assess soil resistance distribution, determine pile integrity, and evaluate
driving system performance. Two strain transducers and two accelerometers were installed
below the pile top at a distance of 3 times of the pile width, as shown in Figure 4.7. The strain
transducers were bolted at the mid-depth of the web, and each of the accelerometers was bolted
on the opposite side of the web at a distance of 3-in (75-mm) from the transducers. The PDA
converts the strain and acceleration signals to force and velocity records as a function of time, as
plotted in Figure 4.8 for ISU5. During pile driving, a record of force and velocity was
continuously collected and displayed by the PDA at every hammer impact on the test pile until
the end of driving (EOD). After the end of driving, all the test piles except ISU1 were re-struck
or re-tapped using the same hammers (see Table 4.2) at a schedule listed in Table 4.3. During
the re-strikes, the force and velocity records were collected using the PDA. The main purpose of
performing the re-strikes is to investigate the change in pile resistance as a function of time. The
gain in pile resistance over time is referred to as pile setup and it has been observed by many
researchers, including Salgado (2008) who believed that the phenomenon is mostly due to the
dissipation of pore pressure and the healing of remolded soil near the pile over time. The PDA
records during the entire re-strikes for ISU5 are shown in Figure 4.9, and the PDA records for
other test piles are included in Appendix C.
Table 4.3. Schedule of re-strikes and PDA tests
Number of Days after EOD
Project
ID
ISU2
ISU3
ISU4
ISU5
ISU6
ISU7
ISU8
ISU9
ISU10
st
nd
rd
1
Re-strike
2
Re-strike
3
Re-strike
4th
Re-strike
5th
Re-strike
6th
Re-strike
7th
Re-strike
8th
Re-strike
0.17
0.0028
0.0041
5.38E-3
1.60E-3
1.86E-3
7.07E-3
3.87E-3
3.78E-3
0.92
0.0073
0.016
0.013
0.0044
0.006
0.011
0.011
0.011
2.97
0.017
0.04097
0.048
0.012
0.015
0.039
0.038
0.039
1.11
0.74
0.92
0.07
0.80
0.97
0.69
0.64
1.95
1.74
2.90
0.83
2.77
3.97
2.87
4.64
4.75
7.92
2.82
6.76
4.95
9.77
-
6.79
9.76
-
9.81
-
The PDA uses the Case Method, developed by Professor Goble and his students at Case Western
Reserve University, which is based on the principle of wave mechanics to determine the static
pile resistance. Using the force and velocity records, the PDA estimates the total soil resistance
(RTL) using Eq. 4-2. Goble et al. (1975) assumed that the total soil resistance was a
combination of static and dynamic resistances, where the dynamic soil resistance was a linear
function of a viscous damping coefficient and the pile toe velocity. Goble et al. (1975) defined
the viscous damping coefficient as a product of a Case damping factor (Jc) and a pile impedance
(Z). The recommended Jc values, specified by Hannigan et al. (1998), are shown in Table 4.4.
The original Jc values were determined by Goble et al. (1975), with the updated Jc values
determined by Dynamic, Inc. (1996) using an additional database. The single best Jc value was
selected from the correlation study for each soil type and tabulated under the “Best Correlation
Value” in Table 4.4.
33
Subtracting the dynamic soil resistance from the total soil resistance, the static soil resistance
(RSP) can be derived from Eq. 4-3. After calculating all RSP values for the data set, where a
different RSP is found at each given time relative to the force and velocity values for that time,
the maximum calculated RSP value is then assigned as the maximum static resistance (RMX) for
the tested soil. For example the force (F1) and velocity (V1) at time of initial impact for ISU5 at
the EOD are 396 kips (1,762 kN) and 14.5 ft/s (4.42 m/s) respectively, and the F2 and V2 are
108 kips (480 kN) and 0 ft/s respectively. For the HP 10 x 42 steel pile (where E=30,000 ksi
(206,843 MPa), A=12.4 in2 (80 cm2) and C=16,808 ft/s (5,123 m/s)), the RTL is computed at
413 kips (1,837 kN). Knowing the RTL and assuming Jc of 0.70 for silty clay soil at the pile toe,
the RSP is computed at 200 kips (890 kN). After searching for the maximum RSP for the entire
record, the RMX is found to be 200 kips (890 kN). The pile static resistance is assumed equal to
the estimated RMX value.
[
]
[
]
[
(4-2)
]
(4-3)
where
RTL
RSP
F1
F2
V1
V2
E
A
C
L
Jc
= Total soil resistance at time t1 of initial hammer impact, kip;
= Static soil resistance at time t1 of initial hammer impact, kip;
= Force measured at transducer location at time t1, kip;
= Force measured at transducer location at time t2 = t1 + 2L/C, kip;
= Velocity measured at accelerometer location at time t1, ft/s;
= Velocity measured at accelerometer location at time t2 = t1 + 2L/C, ft/s;
= Modulus of elasticity of the steel H-piles, ksi;
= Cross sectional area of the steel H-piles, in2;
= Compressive wave speed of the steel H-piles, ft/s;
= The pile length below the transducers or LE used in the PDA, ft; and
= Dimensionless Case damping factor.
Table 4.4. Summary of Case damping factors
Soil Type at Pile Toe
Original Case Damping
Factor
Best
Correlation
Value
Updated Case
Damping Factor
Clean Sand
0.05 to 0.20
0.05
0.10 to 0.15
Silty Sand, Sandy Silt
0.15 to 0.30
0.15
0.15 to 0.25
Silt
0.20 to 0.45
0.3
0.25 to 0.40
Silty Clay, Clayey Silt
0.40 to 0.70
0.55
0.40 to 0.70
Clay
0.60 to 1.10
1.10
0.70 or higher
34
D
Pile Top
Accelerometer
Steel H-Pile
Strain Transducers
3D
3”
Accelerometers
3”
Transducer
1.5”
1.5”
Accelerometer
Steel H-Pile
Longitudinal
Axis
Side View
PDA
Strain Transducer
Section x-x
Figure 4.7. Typical Pile Driving Analyzer (PDA) set up (from Pile Dynamics, Inc., 1996)
Furthermore, the PDA was also used to assess soil resistance distribution along an embedded pile
length. The PDA estimates the shaft resistance (SFR) using Eq. 4-4, and the end bearing is
determined by subtracting the SFR from the estimated pile static resistance (assumed as RMX).
Using the velocity record and the computed wave-up (Wu) of the test pile, as illustrated by ISU5
at EOD as shown in Figure 4.10, the total shaft resistance (SFT) is estimated by extrapolating the
wave-up curve (solid line) and intersecting with the vertical line at the point where the measured
velocity (dash line) reaches zero (Case Western Reserve University et al. 2008), and the SFT is
determined at 375 kips (1,668 kN). Wave-up is defined as the upward moving wave force as
given by Eq. 4-5. The RMX at Jc of 0.7 was determined early at 200 kips (890 kN), and
similarly, the RX0 which is equal to RMX at Jc of zero is estimated at 413 kips (1,837 kN).
Thus, the shaft resistance is computed at 182 kips (810 kN) using Eq. 4-4, which is 91% of the
pile resistance. As such, only 18 kips (80 kN), or 9%, is contributed from the end bearing. Table
4.5 summarizes the Case damping factor (Jc) used, PDA estimated pile static resistance (RMX)
and shaft resistances (SFR) at both EOD and re-strikes.
(
(
35
)
(4-4)
)
(4-5)
LP = 10 ft
LP = 20 ft
LP = 30 ft
LP = 45 ft
LP =55 ft (EOD)
Figure 4.8. PDA force and velocity records during driving and at EOD for ISU5
36
Figure 4.9. PDA force and velocity records during re-strikes for ISU5
37
400
17.74
Wave-Up
Velocity
375 kips
350
300
12.74
Velocity (ft/s)
Wave-Up (kip)
250
200
7.74
150
100
2.74
50
0
-50
-2.26
0
0.05
0.1
Time (second)
0.15
0.2
Figure 4.10. Wave-up and velocity measurement for ISU5 at EOD used to determine shaft
resistance
Table 4.5. Summary of Jc, PDA estimated pile static (RMX) and shaft resistances (SFR)
Project
ID
Jc
ISU1
0.7
ISU2
0.7
ISU3
1.1
ISU4
0.7
ISU5
0.7
ISU6
0.7
ISU7
1.1
ISU8
0.7
ISU9
0.2
ISU10
0.2
EOD
1st
Re-strike
Pile Static Resistance (Pile Shaft Resistance), kips
2nd
3rd
4th
5th
6th
Re-strike
Re-strike
Re-strike
Re-strike Re-strike
141
(118)
107
(87)
120
(119)
143
(107)
200
(182)
146
(144)
-
-
-
148
(132)
117
(117)
144
(110)
224
(200)
151
(149)
162
(145)
123
(122)
143
(109)
229
(203)
149
(149)
146
(137)
128
(128)
154
(142)
248
(217)
145
(142)
0
0
11(3)
164
(142)
226
(226)
158
(117)
161
(148)
217
(216)
160
(124)
169
(156)
215
(199)
163
(134)
7th
Re-strike
8th
Re-strike
-
-
-
-
-
-
-
-
-
-
157
(144)
161
(152)
326
(279)
167
(159)
163
(150)
162
(148)
375
(329)
195
(181)
-
-
-
223
(185)
400
(350)
231
(211)
-
-
-
-
266
(255)
310
(261)
0
31(19)
66(48)
95(76)
93(73)
-
161
(148)
220
(186)
166
(138)
180
(170)
227
(198)
170
(143)
177
(177)
229
(189)
175
(123)
208
(200)
233
(189)
-
-
-
-
-
-
38
-
The PDA can also be used to evaluate driving system performance. The maximum energy
(EMX) transferred from a hammer to a steel H-pile is calculated using Eq. 4-6, based on the
force and velocity records. The performance of the hammers, as indicated in Table 4.2, is
evaluated in terms of the energy transferred ratio (ETR) given by Eq. 4-7, which is defined as the
ratio of maximum energy (EMX) and the manufacturer’s rated hammer energy. For example the
EMX for ISU5 at EOD is determined at 16.3 k-ft (22 kN-m). When dividing the EMX by the
manufacturer’s rated hammer energy of 40.20 k-ft (55 kN-m) as given in Table 4.2 for ISU5, the
ETR of 40.5% is determined. Hannigan et al. (1998) suggests the hammer performance is
considered satisfactory when the estimated ETR is higher than the mean value of 34.3% for a
diesel hammer on steel. Likins et al. (2004) estimated the hammer stroke (STK) of an open end
diesel hammer by using an equivalent hammer blow rate (BPM), as given by Eq. 4-8. The
hammer stroke for ISU5 at EOD with the PDA measured BPM of 44.4 is estimated to be 7.04-ft
(2.15-m).
[∑ ( ) ( ) ]
(4-6)
(4-7)
(
)
(4-8)
To monitor the pile integrity during driving, the PDA calculates the maximum compressive
(CSX) and tensile (TSX) stresses for each hammer impact and compares this with the allowable
stresses specified by the PDA users. The AASHTO (2007) LRFD Bridge Design Specifications
have limited the allowable stress of a steel H-pile to 0.9Fy for both compression and tension. For
example, the allowable stress for a Grade 50 HP 10 x 42 steel pile with a cross sectional area (A)
of 12.4-in2 (80-cm2) is 45 ksi (310 MPa). The maximum measured compressive force (positive)
for ISU5 at EOD is 396 kips (1,762 kN), and the maximum compressive stress (CSX) is
calculated at 31.9 ksi (220 MPa). Similarly, the maximum measured tensile force (negative) is
12 ksi (83 MPa), which yields the maximum tensile stress (TSX) of 1 ksi (7 MPa). Since neither
of the measured stresses exceeds the AASHTO allowable stress limit, the pile integrity during
driving is ensured.
However, pile quality cannot be evaluated solely based on measured pile stresses. Pile can be
damaged even if the measured stresses do not exceed the allowable stress limit. Rausche and
Goble (1979) derived the integrity factor (BTA) in order to describe the degree of convergence
between the force and velocity records within a period 2L/C, where L is the pile length and C is
the wave speed, which give an indication of a reduction in the pile impedance (Z). The BTA
value is determined using Eq. 4-9, and the severity of pile damage is decided using the
classification defined by Rausche and Goble (1979), given in Table 4.6, under the presumption
that BTA indicates how much the pile cross section integrity is retained. For an undamaged pile,
such as ISU5 at EOD, no convergence (i.e., crossing between force and velocity records) occurs
before 2L/C, therefore the α term is zero and BTM equal to 1 (or 100%).
39
(
(
))
(4-9)
where
BTA = Degree of convergence between force and velocity records before 2L/C;
α
= Defining term, dimensionless;
Z
= Pile impedance (see Eq. 4-1), k-s/ft;
Vd = Velocity at location of pile damage after convergence occurred, ft/s;
Fd = Force at location of pile damage after convergence occurred, kip;
F1 = Force at initial hammer impact, kip;
F* = Force at the time before the increase in the velocity become noticeable and
before convergence, kip; and
*
V
= Velocity at the time when it started to increase toward convergence, ft/s.
Table 4.6. Pile damage classification
BTA (Percentage)
Severity of Damage
1.0 (100%)
0.8 – 1.0 (80% - 100%)
Undamaged
Slight damage
0.6 – 0.8 (60% - 80%)
Below 0.6 (below 60%)
Damage
Broken
The PDA force and velocity signals are used as an input for the CAse Pile Wave Analysis
Program (CAPWAP) to improve the estimations of static shaft resistance, end bearing, the load
settlement curve, and to determine the dynamic soil parameters (i.e., quakes and damping
factors). For additional detailed descriptions of the PDA, refer to Ng (2011).
4.5. CAse Pile Wave Analysis Program (CAPWAP)
CAse Pile Wave Analysis Program (CAPWAP) method was developed by Professor Goble and
his students in the 1970s. It is a computer program which uses the PDA records as input data for
a more accurate analysis and estimation of the pile resistance, soil resistance distribution and
dynamic soil properties. CAPWAP is used to refine the PDA results at the end of driving and at
re-strikes by performing a signal matching process with the combination of several analytical
techniques, as described by Pile Dynamics, Inc. (2000). CAPWAP adopts the soil-pile model
developed by Smith (1962) and uses the wave equation algorithm in the analysis. Figure 4.11
shows the CAPWAP model for the 60-ft (18.3-m) long HP 10 x 42 steel pile for ISU5 at Clarke
County. CAPWAP considers the pile length below the location of the PDA transducers and
accelerometers, which is 57.5-ft (17.5-m) for the ISU5 example mentioned. The pile model is
divided into user specified segments of pile masses (m) with approximately equal length, and
each pile mass is connected with a series of elastic springs and linear viscous dampers. The
ISU5 example comprised 22 pile segments of around 2.6-ft (0.8-m) in length. The CAPWAP soil
model at an alternate pile segment is represented by an elastic-plastic spring and a linear damper,
as shown in Figure 4.11. The elastic-plastic spring is characterized by two parameters, static soil
resistance at the soil segment (Rs) and soil quake (q), and the linear damper is characterized by
40
the damping coefficient (Cs). CAPWAP approximately relates the damping coefficient to the
Smith damping factor (Js) and the Case damping factor (Jc), using Eqs. 4-10 and 4-11
respectively. It is important to note that any variation in static soil resistance (Rs) will affect the
Js value, but not the Jc value. For a detailed description of CAPWAP, refer to Pile Dynamics,
Inc. (2000).
(4-10)
∑
(4-11)
PDA Signals
Pile Top
Gauge 2.5 ft
2.5 ft
Location
m1
m2
Pile Lumped Mass
Linear Spring
Linear Viscous Damper
mi-1
m3
HP10x42
Steel Pile
m4
m5
25 ft
Soil Model
Clay
mi
m8
m9
Cp
Kp
m10
m11
m12
4 ft
mi+1
Silty Clay to Clay
m14
10 ft
Static Soil
Rsu Resistance (Rs)
m13
Ks
Clay
m15
Soil Damping
Resistance (Rd)
57.5 ft pile length
w/ 22 pile segment
and 11 soil segment
m6
m7
q Displacement
m16
Velocity
Linear Viscous
Damper
m17
m18
Linear-Plastic
Spring
m19
16 ft
Cs
m20
m21
m22
m23
Silty Clay to Clay
Figure 4.11. Typical CAPWAP model for ISU5 at EOD
The soil resistance at each soil segment, soil quake and either the Smith’s damping factor or the
Case damping factor are adjusted until the best signal matching is achieved, as shown in Figure
4.12 for ISU5 at EOD. The summation of all adjusted soil resistances along the pile shaft gives
the soil shaft resistance, and total pile resistance is determined by adding the shaft resistance with
the soil resistance at the pile toe. Table 4.7 summarizes the CAPWAP estimated pile capacities
and shaft resistances at EOD and re-strikes for all test piles. A constant soil quake is used for all
soil segments along the shaft and a different quake value is used for the soil model at the pile toe.
The adjusted soil quake values for shaft and toe at EOD and re-strikes for all test sites are
summarized in Table 4.8, and Smith’s damping factors are summarized in
Table 4.9.
41
160.0
160.0
ft/sVelocity (ft/s)
CAPWAP Velocity and Wave-Up Signals Matching
for ISU5 at the end of driving.
Wave-Up (kips)
Measured Wave-Up at Pile Top
Computed Wave-Up at Pile Top
Measured Velocity at Pile Top
Computed Velocity at Pile Top
80.0
80.0
00
160 ms
160 ms
0.0
0.0
L/c
4040L/c
Time
Measured Wave Up at Top
Figure
4.12.
Results of CAPWAP signals matching for ISU5 at EOD
Computed Wave
Up at Top
Measured Velocity at Top
Computed Velocity at Top
Table 4.7. Summary of CAPWAP estimated total pile resistances and shaft resistances
Project
ID
-80.0
ISU1
ISU2
ISU3
ISU4
ISU5
ISU6
ISU7
ISU8
ISU9
ISU10
EOD
1st
Re-strike
2nd
Re-strike
Total Pile Resistance (Shaft Resistance), kips
3rd
4th
5th
6th
Re-strike
Re-strike
Re-strike
Re-strike
142
(96)
81
(67)
99
(85)
102
(88)
178
(124)
145
(123)
-
-
-
116
(101)
103
(88)
105
(90)
189
(135)
140
(117)
130
(114)
105
(89)
109
(93)
215
(160)
149
(125)
130
(114)
130
(113)
121
(107)
220
(165)
148
(124)
12(0)
13(1)
19(10)
140
(123)
169
(138)
121
(103)
143
(134)
168
(127)
105
(86)
146
(137)
166
(139)
106
(89)
7th
Re-strike
8th
Re-strike
-
-
-
-
-
-
-
-
-
-
143
(127)
135
(117)
233
(175)
177
(161)
148
(130)
144
(127)
235
(177)
187
(162)
-
-
-
154
(138)
245
(186)
197
(171)
-
-
-
-
211
(185)
211
(186)
32(18)
43(27)
67(47)
69(60)
75(67)
-
153
(139)
161
(131)
114
(96)
155
(135)
159
(127)
121
(103)
159
(120)
157
(124)
118
(100)
160
(117)
155
(115)
-
-
-
-
-
-
42
-
Table 4.8. Summary of CAPWAP estimated soil quake values
Project
ID
ISU1
ISU2
ISU3
ISU4
ISU5
ISU6
ISU7
ISU8
ISU9
ISU10
EOD
0.07
(0.93)
0.05
(0.45)
0.24
(0.04)
0.07
(0.16)
0.07
(0.38)
0.10
(0.31)
0.37
(0.28)
0.11
(0.25)
0.05
(1.00)
0.10
(0.99)
Shaft Quake (Toe Quake), in
3rd
4th
5th
Re-strike
Re-strike
Re-strike
1st
Re-strike
2nd
Re-strike
-
-
-
0.11
(0.28)
0.25
(0.04)
0.10
(0.36)
0.05
(0.09)
0.09
(0.24)
0.15
(0.17)
0.10
(0.27)
0.05
(0.84)
0.11
(0.91)
0.11
(0.49)
0.20
(0.04)
0.08
(0.25)
0.06
(0.10)
0.10
(0.41)
0.15
(0.16)
0.10
(0.26)
0.06
(0.86)
0.11
(0.88)
0.25
(0.41)
0.06
(0.18)
0.07
(0.23)
0.05
(0.10)
0.08
(0.22)
0.14
(0.04)
0.15
(0.35)
0.09
(0.76)
0.12
(0.15)
6th
Re-strike
7th
Re-strike
8th
Re-strike
-
-
-
-
-
-
-
-
-
-
0.12
(0.29)
0.07
(0.40)
0.07
(0.16)
0.05
(0.10)
0.05
(0.06)
0.14
(0.28)
0.07
(0.92)
0.10
(0.98)
0.14
(0.20)
0.12
(0.39)
0.04
(0.16)
0.28
(0.15)
0.04
(0.28)
0.13
(0.51)
0.14
(0.82)
0.11
(0.33)
-
-
-
-
-
0.04
(0.50)
0.05
(0.08)
0.22
(0.22)
0.09
(0.16)
0.12
(0.24)
0.05
(0.89)
-
-
0.31
(0.30)
0.06
(0.10)
0.26
(0.25)
-
-
-
-
-
-
-
-
Table 4.9. Summary of CAPWAP estimated soil Smith’s damping factors
Project
ID
ISU1
ISU2
ISU3
ISU4
ISU5
ISU6
ISU7
ISU8
ISU9
ISU10
EOD
0.082
(0.063)
0.130
(0.160)
0.095
(0.159)
0.122
(0.05)
0.241
(0.038)
0.062
(0.086)
0.398
(0.074)
0.092
(0.134)
0.053
(0.189)
0.084
(0.074)
1st
Re-strike
Shaft Damping Factor (Toe Damping Factor), s/ft
2nd
3rd
4th
5th
6th
Re-strike
Re-strike
Re-strike
Re-strike
Re-strike
-
-
-
0.124
(0.140)
0.118
(0.127)
0.132
(0.086)
0.203
(0.066)
0.064
(0.080)
0.230
(0.209)
0.109
(0.167)
0.088
(0.077)
0.088
(0.186)
0.148
(0.250)
0.120
(0.099)
0.112
(0.181)
0.140
(0.067)
0.075
(0.115)
0.083
(0.126)
0.128
(0.156)
0.082
(0.135)
0.098
(0.134)
0.169
(0.348)
0.064
(0.107)
0.102
(0.123)
0.164
(0.027)
0.074
(0.158)
0.099
(0.136)
0.134
(0.193)
0.108
(0.217)
0.095
(0.060)
7th
Re-strike
8th
Re-strike
-
-
-
-
-
-
-
-
-
-
0.105
(0.070)
0.153
(0.221)
0.215
(0.110)
0.089
(0.092)
0.094
(0.104)
0.146
(0.398)
0.092
(0.202)
0.084
(0.124)
0.128
(0.118)
0.164
(0.448)
0.262
(0.028)
0.151
(0.200)
0.107
(0.027)
0.178
(0.366)
0.117
(0.222)
0.061
(0.051)
-
-
-
-
-
43
0.227
(0.315)
0.203
(0.386)
0.139
(0.384)
0.110
(0.078)
0.147
(0.191)
0.153
(0.140)
-
-
0.166
(0.345)
0.097
(0.182)
0.189
(0.290)
-
-
-
-
-
-
-
-
4.6. Wave Equation Analysis Program (WEAP)
Wave equation analysis method was first introduced by Smith (1962) and was adopted and
upgraded by Goble and Rausche (1976) into a commercial program known as WEAP program.
WEAP is a one-dimensional wave equation analysis software program that simulates the motion
and force on a pile when driven by an impact or vibratory hammer. It is used to assess the
behavior of a pile with different hammers, prior to the pile actually being driven. WEAP requires
input describing the modeling of a hammer driving system, a pile and the surrounding soil
properties and from this computes the blow count, axial driven stress, hammer performance, and
pile bearing resistance. Similar to the CAPWAP model, WEAP models the pile and surrounding
soil in a series of masses, springs and viscous dampers, as shown in Figure 4.13. Unlike
CAPWAP, which uses PDA records to replace the hammer driving system, WEAP completely
models different hammer driving systems, with different combinations of masses, springs and/or
dampers, and the latest commercial WindowsTM operated WEAP program (GRLWEAP) even
includes a database of various hammer types. Modifications of hammer efficiency, pressure and
stroke values, which represent the actual hammer used, are also allowed.
(a) Schematic (b) Model
(a) Schematic
(b) Model
(a) Schematic (b) Model
Diesel Hammer
Vibratory Hammer
External Combustion Hammer
(Air/Steam/Hydraulic)
*
Rs
Hammer Impact
Striker Plate
Cvs
,v
q
,u
Figure 4.13. Wave equation models for different hammers (adapted from Hannigan et al.
1998)
Knowing the pile properties, as listed in Table 4.1, and the hammer types, as listed in Table 4.2,
used in the field tests, WEAP analyses were performed at EOD and re-strikes. Five different
procedures of inputting soil profile data into WEAP were carried out, including: 1) GRLWEAP
soil type based method (ST); 2) GRLWEAP SPT N-value based method (SA); 3) the Federal
44
Highway Administration (FHWA) DRIVEN program; 4) Iowa Blue Book (Iowa DOT steel pile
Design Chart); and 5) Iowa DOT current approach. The static analysis methods used in the static
soil resistance estimation for each procedure are summarized in Table 4.10. The methodology
used in each procedure is briefly described in the following subsections; for a detailed
description, refer to Ng (2011).
4.6.1 GRLWEAP soil type based method (ST)
The GRLWEAP soil type based method (ST) provides the easiest procedure of inputting the soil
information. It requires only the identification of soil types, which aids the input process and
simplifies the soil resistance calculation for both bearing graph and driveability analyses. The
corresponding soil parameters stored in the GRLWEAP are based on the Bowles (1996) and
Fellenius (1996) recommendations, given in Table 4.11 for cohesionless soils and Table 4.12 for
cohesive soils. ST method uses the β-method and the modified α-method to estimate the unit
shaft (qs) and unit toe (qt) resistances for non-cohesive soils and cohesive soils respectively.
4.6.2 GRLWEAP SPT N-value based method (SA)
The GRLWEAP SPT N-value based method (SA) requires the input of soil types, unit weights
and uncorrected SPT N-values. These soil parameters can be obtained from the in-situ SPT tests
and laboratory soil tests, or they can be estimated using Bowles (1996) recommendations, given
in Table 4.13 for cohesionless soils and Table 4.14 for cohesive soils, in the absence of soil test
results. The unit shaft and toe resistances are calculated based on the static analysis methods
listed in Table 4.10.
4.6.3 FHWA’s DRIVEN Program
DRIVEN program generates the entire soil profile of a full pile depth and creates an input file for
WEAP analysis. It requires the soil unit weight for all soil types, which are obtained either from
laboratory soil tests, or from Table 4.13 for cohesionless soils and Table 4.14 for cohesive soils.
SPT N-value is used to define cohesionless soil characteristic and undrained shear strength (Su)
is required to define the cohesive soil strength. The undrained shear strength (Su) is estimated
either from the CPT, described in Section 3.2, or by taking half of the unconfined compressive
strength (qu) given in Table 4.14. Next, the unit shaft and toe resistances are calculated based on
static analysis methods, as listed in Table 4.10. For a detailed description of the DRIVEN
program, refer to FHWA DRIVEN User’s Manual (Mathias and Cribbs 1998).
4.6.4 Iowa Blue Book Method
WEAP analysis based on the Iowa Blue Book method uses the Iowa DOT pile design charts, as
shown in Table 4.15 and Table 4.16, for determining the unit shaft (qs) and unit toe (qt)
resistances. The friction value (in kips/ft) is chosen from the design chart with reference to the
width of the steel H-pile, the soil description and the SPT N-value, then this is divided by the
perimeter of the boxed section of a steel H-pile to determine the unit shaft resistance. For
example, the unit shaft for ISU5 (HP 10 x 42 steel H-pile) at about 19-ft (5.8-m) depth with a
clay soil and a SPT N-value of 9 (see Figure 3.2) is calculated at 0.601 ksf (29 kPa), found by
dividing the friction value of 2.0 kip/ft with the square perimeter of 3.33-ft (1-m). However, a
surface perimeter for the H section was assumed for calculating the unit shaft for sand or
45
cohesionless soil. The toe resistance (in kips) is determined by multiplying the unit end bearing
value (in ksi) with the cross sectional area of the H-pile for any soil conditions, assuming soil
plug does not occur in cohesive or clay soil. The calculated unit shaft resistance and the toe
resistances, as tabulated in Table 4.17 and Table 4.18 respectively, shall be inserted directly into
the WEAP’s variable resistance distribution table for driveability and bearing graph analyses.
4.6.5 Iowa DOT Method
The Iowa DOT method uses the SPT N-values as the only soil parameter, which is input into the
WEAP’s variable resistance distribution table, with respect to the depth where the SPT N-values
are taken. Static geotechnical analysis and driveability analysis are not able to be performed
since the SPT N-values only serve to define the relative and approximate stiffness of the soil
profile. However, a bearing graph analysis can be performed to estimate pile resistance.
Despite the various procedures of inputting the soil profiles, the following assumptions are made
and applied to all procedures during the WEAP analysis.
1) Water table remains constant at EOD and at re-strikes
2) The percentage of shaft resistance used in the bearing graph analysis is determined and
assumed from the static geotechnical analysis
3) No residual stress analysis is considered
4) The soil geostatic stress within the pre-drilling depth is treated as an overburden pressure,
and the pile embedded length does not include the pre-drilling depth
5) Bearing graph analysis based on an equal distribution of total pile capacity on shaft and
toe components are selected.
Soil quake (q) and damping coefficient (Cs) are the dynamic soil parameters that describe the soil
model. The WEAP recommended soil quake values for shaft and toe soil segments are given in
Table 4.19, and are used in the five procedures of defining the soil profile. Five approaches are
available in WEAP to define the damping coefficient; however the Smith damping (Eq. 4-10) is
the most commonly used in practice. For a detailed description of the five damping options,
refer to Pile Dynamics, Inc (2005). The relationship between the damping coefficient (Cs) and
the Smith’s damping factor (Js) is given by Eq. 4-10. The WEAP recommended Smith’s
damping factors for shaft and toe soil segments, as outlined in Table 4.20 are used in the WEAP
analyses for all procedures except the Iowa DOT method. The damping factors used in the Iowa
DOT method are given in Table 4.21 based on different soil types. Furthermore, the Smith’s
damping factors are applied consistently to all soil segments, whereas in the Iowa DOT method
various damping factors are chosen, from Table 4.21, based on different soil layers along a pile.
46
Table 4.10. Summary of static analysis methods used in the five soil profile input procedures
Soil Types
Input
Procedure
Sand
(Non-cohesive, drained)
Unit Shaft
ST
(Soil Type Based
Method: PDI,
2005)
SA
(SPT N-Value
Based Method:
PDI, 2005)
β-method
(Esrig and Kirby 1979)
'
'
ko tanφ σ v
≤ 5 ksf
Nordlund
DRIVEN
(FHWA, Mathias
(1963,1979)
and Cribbs, 1998) Thurman (1964)
Blue Book
(Iowa DOT
Design Chart,
Dirks and Kam,
1994)
Iowa DOT
current practice
Unit Toe
Meyerhoff's
semi-empirical
method
4.18 N
≤ 250 ksf
Silt
(Non-cohesive, drained)
Unit Shaft
Unit Toe
β-method
(Esrig and Kirby 1979)
Silt
(Cohesive, undrained)
Unit Shaft
Unit Toe
Modified α-method based on
unconfined compressive strength
Bjerrum-Borland
Bjerrum-Borland
β-method (based on Nt σ'v ≤ 125 ksf
β-method
Nt σ'v ≤ 125 ksf (Nt
Fellenius 1996
(Nt from Fellenius (based on Fellenius from Fellenius
linear interpolation
1996)
1996 linear
1996)
of β)
interpolation of β)
Nordlund/
Thurman limited
by Meyerhoff
(1976)
Nordlund
(1963,1979)
Thurman (1964)
Wave Equation
concept using SPT
N-values
Meyerhoff's
semi-empirical
method
Nordlund/
Thurman limited
by Meyerhoff
(1976)
Clay
(Cohesive, undrained)
Unit Shaft
Modified α-method based on
unconfined compressive strength
ko tanφ' σ'v
≤ 1.6 ksf
1.127 N
≤ 68 ksf
α-method
9Su
α-method
9Su
(Tomlinson 1971) (Tomlinson 1971) (Tomlinson 1971) (Tomlinson 1971)
Wave Equation
Wave Equation
α-method
α-method
concept using SPT
concept using SPT
(Tomlinson 1971)
(Tomlinson 1971)
N-values
N-values
Used SPT N-values and variable pile profile option in the WEAP
47
Unit Toe
Wave Equation
concept using
SPT N-values
Table 4.11. Soil Parameters for cohesionless soils
Soil Type
SPT
N-Value
Friction
Angle
(Degree)
Unit
Weight
(lb/ft³)
β
Value
Very Loose
Loose
2
7
25 - 30
27 - 32
85.9
101.8
0.203
0.242
Toe
Bearing
Capacity
Coefficient
(Nt)
12.1
18.1
Medium
20
30 - 35
117.8
0.313
Dense
Very Dense
40
50+
35 - 40
38 - 43
124.1
140.0
0.483
0.627
Maximum
Unit Shaft
Resistance,
qs (ksf)
Maximum
Unit Toe
Resistance, qt
(ksf)
0.5
1.0
50
100
33.2
1.5
150
86.0
147.0
2.0
4.0
200
400
Table 4.12. Soil Parameters for cohesive soils
111.4
Maximum
Unit Shaft
Resistance, qs
(ksf)
0.07
Maximum
Unit Toe
Resistance, qt
(ksf)
1.13
0.75
111.4
0.22
3.38
6
1.50
117.8
0.40
6.77
12
3.00
130.5
0.80
13.53
24
6.00
130.5
1.33
27.07
32+
8.00
120.9 – 140.0
1.61
36.10
Soil Type
SPT
N-Value
Unconfined
Compressive
Strength, qu (ksf)
Unit
Weight
(lb/ft³)
Very Soft
1
0.25
Soft
3
Medium
Stiff
Very Stiff
Hard
Table 4.13. Empirical values for ø, Dr, and γ of cohesionless soils based on Bowles (1996)
Description
Very Loose
Loose
Medium
Dense
Very Dense
Relative Density, Dr
Corrected
N-values
Approximate frictional
angle, ø
Approximate moist
unit weight, γ (lb/ft³)
0 - 0.15
0.15 - 0.35
0.35 - 0.65
0.65 - 0.85
0.85 - 1.00
0-4
4 - 10
10 - 30
30 - 50
50+
25 - 30˚
27 - 32˚
30 - 35˚
35 - 40˚
38 - 43˚
70.0 - 99.9
89.8 - 115.2
110.1 - 129.9
110.1 - 140.0
129.9 - 150.2
Table 4.14. Empirical values for qu and γ of cohesive soils based on Bowles (1996)
Description
Unconfined
compressive
strength, qu (ksf)
Uncorrected
N-values
Saturated unit
weight, γ (lb/ft³)
Very Soft
Soft
Medium
Stiff
Very Stiff
Hard
0 - 0.5
0.5 - 1.0
1.0 - 2.0
2.0 - 4.0
4.0 - 8.0
8.0+
0-2
2-4
4-8
8 - 16
16 - 32
32+
100.6 119.7
100.6 119.7
110.1 - 129.9
119.7 140.0
119.7 140.0
119.7 140.0
48
Table 4.15. Iowa pile design chart for friction bearing Grade 50 steel H-piles
SOIL DESCRIPTION
LRFD DRIVEN PILE FOUNDATION GEOTECHNICAL RESISTANCE CHART, ENGLISH UNITS
SPT N-VALUE
ESTIMATED NOMINAL RESISTANCE VALUES FOR FRICTION PILE IN KIPS/FT
Alluvium or Loess
MEAN
RANGE
HP 10
HP 12
HP 14
Very soft silty clay
1
0-1
0.4
0.8
0.8
Soft silty clay
Stiff silty clay
Firm silty clay
Stiff silt
Stiff sandy silt
Stiff sandy clay
Silty sand
Clayey sand
Fine sand
Coarse sand
Gravely sand
Granular material
3
6
11
6
6
6
8
13
15
20
21
> 40
2-4
4-8
7 - 15
3-7
4-8
4-8
3 - 13
6 - 20
8 - 22
12 - 28
11 - 31
-
0.8
1.2
2.0
1.2
1.2
1.2
1.2
1.6
2.0
2.8
2.8
4.0
1.2
1.6
2.4
1.6
1.6
1.6
1.2
2.0
2.4
3.2
3.2
4.8
1.2
2.0
2.8
1.6
1.6
2.0
1.6
2.8
2.8
3.6
3.6
5.6
Glacial Clay
MEAN
RANGE
HP 10
HP 12
HP 14
Firm silty glacial clay
Firm clay (gumbotil)
11
12
7 - 15
9 - 15
2.4
2.8
3.2
2.4
2.8
3.2
2.8
3.2
3.6
Firm glacial clay(1)
11
7 - 15
[3.2]
[4.0]
[4.4]
2.8
3.2
3.6
Firm sandy glacial clay(1)
13
9 - 15
[3.2]
[4.0]
[4.4]
2.8
3.2
3.6
Firm-very firm glacial clay(1)
14
11 - 17
[4.0]
[4.8]
[5.6]
2.8
3.2
3.6
Very firm glacial clay(1)
24
17 - 30
[4.0]
[4.8]
[5.6]
2.8
3.2
3.6
Very firm sandy glacial clay(1)
25
15 - 30
[4.0]
[4.8]
[5.6]
2.8
3.2
3.6
Cohesive or glacial material(1)
> 35
[4.0]
[4.8]
[5.6]
(1)
- For double entries the upper value is for an embedded pile within 30 feet of the natural ground elevation, and the lower value [ ] is for pile depths more than 30 feet below
the natural ground elevation.
49
Table 4.16. Iowa pile design chart for end bearing Grade 50 steel H-piles
LRFD DRIVEN PILE FOUNDATION GEOTECHNICAL RESISTANCE CHART, ENGLISH UNITS
SOIL
DESCRIPTION
SPT N-VALUE
MEAN
RANGE
Granular material
< 15
-
Fine or medium sand
Coarse sand
Gravely sand
15
20
21
25
12
20
25 - 50
50 - 100
100 - 300
> 300
100 - 200
> 200
10 - 50
-
25
50
100
-
Granular material
Bedrock
Cohesive material
ESTIMATED NOMINAL RESISTANCE VALUES FOR END BEARING PILE IN KSI
HP 10
HP 12
HP 14
Do not consider end bearing
2-4
4-8
8-16
18
12
18
2-4
4-8
8-16
18
12
18
Do not consider end bearing
1
1
2
4
7
2
4
7
50
2-4
4-8
8-18
18
12
18
1
2
4
7
Table 4.17. Revised Iowa pile design chart used in WEAP for friction bearing Grade 50 steel H-piles
SOIL DESCRIPTION
Alluvium or Loess
LRFD DRIVEN PILE FOUNDATION GEOTECHNICAL RESISTANCE CHART, ENGLISH UNITS
ESTIMATED NOMINAL RESISTANCE VALUES FOR FRICTION PILE IN KIPS PER SQUARE
SPT N-VALUE
FOOT (KSF)
MEAN
RANGE
HP 10
HP 12
HP 14
Very soft silty clay
Soft silty clay
Stiff silty clay
Firm silty clay
Stiff silt
Stiff sandy silt
Stiff sandy clay
1
3
6
11
6
6
6
0-1
2-4
4-8
7 - 15
3-7
4-8
4-8
Silty sand
Clayey sand
Fine sand
Coarse sand
Gravely sand
Granular material
8
13
15
20
21
> 40
3 - 13
6 - 20
8 - 22
12 - 28
11 - 31
-
Glacial Clay
MEAN
RANGE
Firm silty glacial clay
Firm clay (gumbotil)
11
12
7 - 15
9 - 15
0.12
0.24
0.36
0.60
0.36
0.36
0.36
0.25
0.33
0.20
0.30
0.40
0.60
0.40
0.40
0.40
0.21
0.34
0.17
0.26
0.43
0.60
0.34
0.34
0.43
0.23
0.40
0.41
0.58
0.58
0.83
HP 10
0.41
0.55
0.55
0.82
HP 12
0.40
0.52
0.52
0.80
HP 14
0.72
0.70
0.69
0.72
0.70
0.69
0.84
0.80
0.77
(1)
Firm glacial clay
11
7 - 15
[0.96]
[1.00]
[0.94]
0.84
0.80
0.77
Firm sandy glacial clay(1)
13
9 - 15
[0.96]
[1.00]
[0.94]
0.84
0.80
0.77
Firm-very firm glacial clay(1)
14
11 - 17
[1.20]
[1.20]
[1.20]
0.84
0.80
0.77
Very firm glacial clay(1)
24
17 - 30
[1.20]
[1.20]
[1.20]
0.84
0.80
0.77
Very firm sandy glacial clay(1)
25
15 - 30
[1.20]
[1.20]
[1.20]
0.84
0.80
0.77
Cohesive or glacial material(1)
> 35
[1.20]
[1.20]
[1.20]
(1)
- For double entries the upper value is for an embedded pile within 30 feet of the natural ground elevation, and the lower value [ ] is for pile depths more than 30 feet below
the natural ground elevation.
51
Table 4.18. Revised Iowa pile design chart used in WEAP for end bearing Grade 50 steel H-piles
LRFD DRIVEN PILE FOUNDATION GEOTECHNICAL RESISTANCE CHART, ENGLISH UNITS
SOIL
DESCRIPTION
SPT N-VALUE
MEAN
RANGE
Granular material
< 15
-
Fine or medium sand
Coarse sand
Gravely sand
15
20
21
25
12
20
25 - 50
50 - 100
100 - 300
> 300
100 - 200
> 200
10 - 50
-
25
50
100
-
Granular material
Bedrock
Cohesive material
ESTIMATED NOMINAL RESISTANCE VALUES FOR END BEARING PILE IN KIPS
HP 10
HP 12
HP 14
Do not consider end bearing
24.8-49.6
49.6-99.2
99.2-198.4
223.2
148.8
223.2
31-62
62-124
124-248
279
186
279
Do not consider end bearing
42.8-85.6
85.6-171.2
171.2-385.2
385.2
256.8
385.2
12.4
24.8
49.6
15.5
31
62
21.4
42.8
85.6
86.8
108.5
149.8
52
Table 4.19. WEAP recommended soil quake values (Pile Dynamics, Inc., 2005)
Soil Type
(Pile Type)
All soil types, soft rock (Non-displacement piles)
Very dense or hard soils
(Displacement piles of diameter or width D)
Loose or soft soils
(Displacement piles of diameter or width D)
Hard rock (All pile types)
Shaft Quake
(in)
0.10
Toe Quake
(in)
0.10
0.10
D/120
0.10
D/60
0.10
0.04
Table 4.20. WEAP recommended Smith’s damping factors used in ST, SA, Driven and
Iowa Blue Book (Pile Dynamics, Inc., 2005)
Non-cohesive soils
Smith’s Shaft
Damping Factor (s/ft)
0.05
Smith’s Toe Damping
Factor (s/ft)
0.15
Cohesive soils
0.20
0.15
Soil Types
Table 4.21. Damping factors used in the Iowa DOT method
Rock
Shaft Damping
Factor (s/ft)
0.05
Toe Damping
Factor (s/ft)
0.05
Boulder & Gravel or Gravel Sand
0.10
0.05
Medium Sand or Fine Sand
0.10
0.10
Packed Sand
0.10
0.05
Silt
0.15
0.12
Silty Clay, Silty Clay, Sandy Clay or Firm Sandy Glacial Clay
0.12
0.12
Firm Clay
0.15
0.12
Firm Glacial Clay or Firm Silty Glacial Clay
0.15
0.15
Soil Types
Pile capacities at EOD and re-strikes are estimated using the measured hammer blow count, as
listed in Table 4.22. The hammer blow count is defined as the amount of hammer blows
required to cause one foot (1-ft) pile penetration into the ground. Using the measured hammer
blow count, the corresponding pile resistance at each loading stage is determined from the
WEAP generated bearing graph. For example, the pile resistance of 166 kips (738 kN) is
determined from the bearing graph, as shown in Figure 4.14 for ISU5 at EOD using the Iowa
DOT method with respect to the measured blow count of 26. Table 4.23 presents the estimated
pile capacities for all events (EOD and re-strikes) using the five soil profile input procedures.
Furthermore, given the hammer information, WEAP estimates the hammer stroke as a function
of hammer blow count, as seen in Figure 4.14 for ISU5 at EOD. The bearing graph analysis also
generates relationships between pile compressive/tensile stresses and hammer blow count, as
illustrated in Figure 4.15 for ISU5 at EOD. In this example, both the compressive (38.25 ksi or
264 MPa) and tensile (6.7 ksi or 46 MPa) stresses at the hammer blow count of 26 are less than
the allowable driving stress of 45 ksi (310 MPa) for a Grade 50 steel H-pile. The WEAP
analysis shows that the pile is not overstressed at EOD. In general, WEAP is used to evaluate
hammer performance, ensure pile integrity, and estimate pile resistance, however the estimated
53
hammer strokes and pile stresses are not tabulated here because the main purpose of performing
the WEAP analysis on this occasion is to estimate pile capacities.
Table 4.22. Measured hammer blow count at EOD and re-strikes
Project
ID
EOD
ISU1
Measured Hammer Blow Count (blow/ft)
3rd
4th
5th
6th
Re-strike
Re-strike
Re-strike
Re-strike
-
13
1st
Re-strike
-
2nd
Re-strike
-
7th
Re-strike
-
8th
Re-strike
-
ISU2
10
14
18
22
-
-
ISU3
10
16
16
16
18
20
-
-
-
-
-
-
ISU4
13
15
18
16
21
24
26
-
-
ISU5
26
36
37
38
44
54
72
-
-
ISU6
21
20
22
ISU7
1
3
3
25
29
38
44
53
60
3
7
7
8
8
-
ISU8
19
20
21
21
28
30
31
-
-
ISU9
17
15
16
15
17
14
15
-
-
ISU10
15
10
10
12
14
12
-
-
-
Figure 4.14. WEAP generated bearing graph for ISU5 at EOD using the Iowa DOT method
54
Figure 4.15. WEAP estimated pile stresses for ISU5 at EOD using the Iowa DOT method
Table 4.23. Summary of WEAP estimated pile capacities for all loading stages and all test
piles using different soil input options
Project
ID
EOD
ISU1
ISU2
ISU3
ISU4
ISU5
ISU6
ISU7
ISU8
ISU9
ISU10
107
77
82
98
144
135
8
137
178
154
Project
ID
EOD
ISU1
ISU2
ISU3
ISU4
ISU5
ISU6
ISU7
ISU8
ISU9
ISU10
102
77
82
95
143
138
9
138
160
159
1st
Re-strike
101
110
110
180
129
24
143
162
114
1st
Re-strike
101
111
106
178
133
23
145
149
117
WEAP Estimated Pile Resistance using ST Method (kip)
2nd
3rd
4th
5th
6th
Re-strike
Re-strike
Re-strike
Re-strike
Re-strike
123
138
110
110
121
161
127
116
139
152
160
184
187
206
232
261
138
149
162
191
211
30
31
62
65
68
145
148
173
179
183
171
163
177
159
161
114
131
147
135
WEAP Estimated Pile Resistance using SA Method (kip)
2nd
3rd
4th
5th
6th
Re-strike
Re-strike
Re-strike
Re-strike
Re-strike
123
139
111
111
121
132
122
112
133
147
154
182
185
203
228
256
142
153
166
198
217
28
29
58
61
64
146
149
177
179
183
155
149
160
144
146
117
135
151
138
-
55
7th
Re-strike
231
70
-
8th
Re-strike
245
-
7th
Re-strike
239
65
-
8th
Re-strike
252
-
Project
ID
EOD
ISU1
ISU2
ISU3
ISU4
ISU5
ISU6
ISU7
ISU8
ISU9
ISU10
131
78
82
95
142
135
13
125
185
162
Project
ID
EOD
ISU1
ISU2
ISU3
ISU4
ISU5
ISU6
ISU7
ISU8
ISU9
ISU10
106
77
82
95
143
140
9
136
166
154
Project
ID
EOD
ISU1
ISU2
ISU3
ISU4
ISU5
ISU6
ISU7
ISU8
ISU9
ISU10
117
95
92
115
166
164
10
152
155
143
1st
Re-strike
102
111
106
177
130
23
131
169
119
1st
Re-strike
100
111
106
178
133
24
143
152
112
1st
Re-strike
123
133
127
208
158
25
160
142
107
WEAP Estimated Pile Resistance using DRIVEN Method (kip)
2nd
3rd
4th
5th
6th
7th
Re-strike
Re-strike
Re-strike
Re-strike
Re-strike
Re-strike
124
139
111
111
122
132
122
112
133
147
155
181
184
201
224
252
139
149
163
193
213
234
28
29
58
61
64
66
133
136
160
166
170
177
169
183
164
166
119
138
154
141
WEAP Estimated Pile Resistance using Blue Book Method (kip)
2nd
3rd
4th
5th
6th
7th
Re-strike
Re-strike
Re-strike
Re-strike
Re-strike
Re-strike
123
138
111
111
121
131
122
112
133
147
155
182
185
203
227
256
143
153
167
198
217
240
27
29
58
61
64
66
144
147
172
179
182
159
152
164
148
150
113
130
145
133
WEAP Estimated Pile Resistance using Iowa DOT Method (kip)
2nd
3rd
4th
5th
6th
7th
Re-strike
Re-strike
Re-strike
Re-strike
Re-strike
Re-strike
150
169
133
133
146
160
146
134
159
174
183
212
216
236
263
295
168
179
195
230
252
276
30
32
65
68
71
73
161
164
190
198
202
148
141
154
138
139
107
121
135
123
-
8th
Re-strike
247
8th
Re-strike
252
8th
Re-strike
291
-
4.7. Vertical Static Load Tests
After completing all the re-strikes, vertical static load tests were performed on the test piles in
accordance with ASTM D1143 Procedure A: Quick test method. AASHTO (2007) LRFD bridge
specifications require that the static load test shall be performed a minimum of five (5) days after
the pile is installed and the quick load test method shall be used to measure the pile resistance.
The schematic diagram of the static axial load test for ISU5 at Clarke County, using a hydraulic
jack acting against a frame utilizing two anchored reaction piles, is shown in Figure 4.17. After
installing the test pile, two HP 10 x 42 anchor piles were installed with 72-in. (1.8-m) exposed
lengths, in line with the test pile and with a minimum clear distance of five (5) times the
diameter of the largest pile (total clearance of 50-in or 1.3-m), as shown in Figure 4.18. This is
in accordance with AASHTO (2007) specifications, which require a minimum distance of 30-in
(760-mm) or 2.5 diameters in order to avoid any influence of the anchor piles on the test pile.
56
Note that the test pile and the anchored piles were oriented with all the flanges parallel to each
other for the ease of setting up the static load test frame.
Some of the test piles experienced minimal local bucking on the flanges near the pile head due to
hard driving, as illustrated in Figure 4.16. The buckled section, usually of about 6-in. (150-mm)
to 12-in. (300-mm), was cut off to provide a level and even surface before the loading jack and
steel plates were placed on the test pile. After the anchored piles had been driven, four (4) 40-in.
(1-m) pile segments were prepared and continuously welded onto the flanges of the anchored
piles, as shown in Figure 4.19. The main reaction beam was lifted and placed on top of the
anchored piles, with the clamping beams and height adjusters then placed atop the reaction beam.
The 3-in. (75-mm) diameter steel rods were then lowered through holes in the height adjusters
and clamping beams and through the spaces between the flanges of the 40-in. (1-m) pile
segments. Sleeved rod nuts were tightened against the bottom plate directly underneath the 40-in.
(1-m) pile segment. The completed static load test frame is shown in Figure 4.19. Next, steel
plates were placed on top of the test pile and followed by a 200 ton (1,779 kN) hydraulic jack,
cylindrical steel tube and load cell. The remaining gap between the load cell and the bottom of
the main reaction beam was filled with layers of shim plates. The hydraulic jack was connected
to an electrical pump which extended and retrieved the jack during the loading and unloading
stages respectively.
The amount of force applied vertically on the test pile was measured and recorded by the load
cell, which was connected to a data acquisition system. When a vertical load was applied on the
test pile, an equal and opposite vertical load was exerted upward on the main reaction beam,
which was resisted by the clamping beams and height adjusters at both ends. The resisting force
on the clamping beams and height adjusters was transferred to the 3-in. (75-mm) diameter steel
rods which reacted against the steel plates on the bottom of the 40-in (1-m) pile segments,
welded onto the anchored piles. The vertical load was eventually transferred to the anchored
piles, which were supported by the shaft soil resistance along their embedded length of 54-ft
(16.5-m). Since the test pile had a similar embedded length and was mainly a frictional pile, the
static load test frame system provided a safety factor of about 2.0, due to the friction resistance
of the anchor piles.
Figure 4.16. Minimal buckling on flanges at pile head
57
Steel Angle
3
(L 2 x 2 x 16
)
Steel Angle
3
(L 2 x 2 x 16
)
Figure 4.17. Schematic drawing of vertical static load test for ISU5 at Clarke County
58
Figure 4.18. Configuration of two anchor piles and a test pile for ISU5 at Clarke County
59
(a) Welded 40 in. short
segment onto flanges
(b) A test pile between two anchored piles
(c) Assembled a main reaction beam, clamping (d) Placed load cell and jack
beams and height adjusters; Fastened with steel rods between test pile and beam
(e) Set up data acquisition
system
(f) Completed static load test frame
Figure 4.19. Setting up of the static load test
60
During testing readings from strain gauges installed along the pile and displacement gauges were
recorded at load increments of 5% of the anticipated failure load. During each load interval, the
load was kept constant for a time interval of not less than four (4) minutes and not more than
fifteen (15) minutes. During the unloading testing stage, a similar procedure was applied at 10%
load decrement. The strain gauge instrumentation is described in detail in Section 4-3 and the
displacement transducers instrumentation is shown in Figure 4.20. Four (4) 10-in. (250-mm)
stroke displacement transducers were utilized, with each pair located close to both sides of the
test pile flanges. The displacement gauges were bolted on 2×4-in. (40×90-mm) wooden
reference beams, which were supported by wooden ladders approximately 3-ft (900-mm) away
from the test pile on either side, as shown in Figure 4.19 and Figure 4.20. This setting allowed
the measurement of vertical pile movement independent of any movement of the loading frame.
The extendable strings of the displacement transducers were connected to eye hooks mounted on
wooden blocks adhered to the flanges of the test pile, as illustrated in Figure 4.20.
Vertical pile displacement was recorded during each static load test and a load displacement
curve was plotted for each test pile to determine the pile resistance, using the Davisson’s criteria,
as shown in Figure 4.21 for ISU5. The procedure of determining the pile resistance is given by:
(1) drawing the pile elastic stiffness line (dashed-orange line), calculated using Eq. 4-12; (2)
offsetting the line by an additional displacement (δ∆), given by Eq. 4-13, to form the Davisson’s
line (red line); (3) identifying the intersection point (in green circle) between the Davisson’s line
and the load-displacement curve (blue line); and (4) determining the applied load (Q)
corresponding to the intersection point. Due to the contribution of soil stiffness surrounding
ISU5, Figure 4.21 shows that the load displacement curve was plotted above the pile elastic
stiffness line. The measured pile capacities from static load tests based on the Davisson’s criteria
are summarized in Table 4.24 and the load-displacement curves are included in Appendix C for
all test piles. The distribution of the measured pile capacities along the embedded pile length is
described in Section 5.
(4-12)
δ
(4-13)
where
∆e
Q
L
A
E
δ∆
D
= Pile structural elastic displacement, in;
= Applied static load on top of the test pile, kip;
= Total pile length, in;
= Cross-sectional area of the test pile, in2;
= Modulus of elasticity of the test pile, ksi;
= Additional displacement for offsetting the pile elastic line, in; and
= Pile width or diameter, in.
61
Figure 4.20. Pile top vertical displacement transducers instrumentation
Load , Q (kip)
0
50
100
150
200
250
300
0.0
Pile Resistance
243 kips
0.1
0.2
Displacement, ∆ (in)
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Figure 4.21. A load-displacement curve and Davisson’s criteria for ISU5 at Clarke County
62
Table 4.24. Summary of static load test results
Number of Days after
EOD
100
Embedded Pile Length before
Static Load Test (ft)
32.50
Measured Pile
Resistance (kip)
212
ISU2
9
55.83
125
ISU3
36
51.00
150
ISU4
16
56.78
154
ISU5
9
56.67
243
ISU6
14
57.2
213
ISU7
13
26.9
53
ISU8
15
57.21
162
ISU9
25
49.5
158
ISU10
6
49.17
127
Project ID
ISU1
63
CHAPTER 5: INTERPRETATION AND ANALYSIS OF FIELD DATA
5.1. Introduction
The aforementioned experimental research studies generate important data for concurrent
analytical and computational investigations. In pursuing the objectives of this research for pile
resistance quantifications and LRFD resistance factor calibrations, the soil properties measured,
using both in-situ and laboratory tests, and pile responses measured, during re-strikes and from
static load tests (SLTs), were interpreted and analyzed. The strain measurements collected from
SLTs were employed to evaluate the pile load distribution along the embedded pile length and to
determine the shaft resistance and end bearing. Particularly, using the static load test results and
soil properties measured using mBST, load transfer analyses were performed by AbdelSalam
(2010) using TZPILE software to simulate the pile load-displacement relationship. In addition,
the measured soil properties were correlated with the increase in pile resistances as a function of
time (i.e., pile setup), determined using dynamic analysis methods during re-strikes and
measured using SLTs. Due to the economic benefits of incorporating pile setup during pile
designs in cohesive soil, pile setup analytical quantification methods were developed in terms of
measured soil properties. The proposed setup methods were validated using PILOT database.
To expand the application of the proposed pile setup methods, LRFD resistance factors for pile
setup were calibrated by Ng (2011), from which the recommendations were documented in the
LRFD Report Volume III by AbdelSalam et al. (2011). Additional detailed data interpretation
and analyses have also been performed on static analysis methods by AbdelSalam (2010),
dynamic analysis methods by Ng (2011) and dynamic formulae by Roling (2010).
5.2. Pile Resistance Distribution
The measured strains (ε) along an embedded test pile length during the static load test were
converted to pile forces (F) using Eq. (5-1) at each load increment (Q) based on pile elastic
modulus (E) and pile cross-sectional area (A). The distribution of pile forces for test pile ISU5 is
drawn in Figure 5.1, and similar force distributions for other test piles are included in the
Appendix D.1.
F=εEA
(5-1)
The force distribution for ISU5 corresponding to the nominal measured pile resistance (Qm) of
243 kips (1081 kN) based on the Davisson’s criteria (indicated by the solid line without markers
shown in Figure 5.1) was established by interpolation of the force distribution curves relating to
236.2 kips (1050 kN) and 250.4 kips (1114 kN). By extending the slope of the pile force curve
along the pile length over the bottom two pairs of strain data, the end bearing contribution was
estimated at the toe of each pile. In this case, the end bearing component at the embedded pile
length of 56.67-ft (17.28-m) was 55.5 kips (247 kN) or 23% of the total pile resistance of 243
kips (1081 kN). Subtracting the end bearing resistance from the total nominal pile resistance, the
shaft resistance for ISU5 was determined to be 187.5 kips (834 kN). Table 5.1 lists the shaft
resistance and end bearing for all test piles except ISU1, which had no strain instrumentation,
and ISU6, ISU7 and ISU10, for which a large number of strain gauges failed during the test and
thus this information could not be extracted with sufficient accuracy. For comparison with the
64
measurements obtained from SLTs, the shaft resistance and end bearing values estimated at the
last re-strike using CAPWAP are reported in Table 5.1. It is important to note from both results
that the total pile resistance is comprised predominately of the shaft resistance, while the end
bearing contribution ranges only between 2% to 28% of the total pile resistance.
0
25
50
75
Pile Force Distribution (kip)
100 125 150 175 200
225
250
275
300
0
Q=13.6 kips
Q=28.8 kips
5
Q=42.9 kips
Depth Below Ground (ft)
10
Q=58.1 kips
Q=71.9 kips
15
Clay (CL)
Q=89.6 kips
Q=102.5 kips
20
Q=118.2 kips
25
Silty Clay to Clay (CL)
30
Clay (CL)
Q=148 kips
Q=163 kips
GWT
35
Q=133.3 kips
Q=179 kips
Q=193.7 kips
40
45
Q=208 kips
Silty Clay to Clay (CL)
Q=222.3 kips
Q=236.2 kips
50
Q=250.4 kips
Q=263 kips
55
Qm=243 kips
60
Figure 5.1. Pile force distribution along the embedded pile length of test pile ISU5
Following this, the SLT shaft resistance distribution is systematically determined from the pile
force distribution curve at the nominal pile resistance (Qm) by calculating the difference in forces
of two consecutive gauges and plotting these differences with respect to their median locations,
as shown in Figure 5.2 for ISU5 and represented by a smoothed line without markers. For a
comparative purpose, similar shaft resistance distributions estimated using CAPWAP during the
beginning of re-strikes (BOR) are plotted in Figure 5.2. It was observed that the shaft resistance
was higher at the stiffer soil layer between 30-ft and 50-ft (9-m and 15-m), characterized with
relatively large uncorrected SPT N-values of 20 and 22. The estimated distributions generally
follow the trend of the measured distribution, where the differences between estimated and
measured resistances reduce from EOD to BOR6. Similar observations are noticed on other test
piles as presented in Appendix D.2.
65
Table 5.1. Summary of shaft resistance and end bearing from static load test results and
last re-strike using CAPWAP
a
Static Load Test Results
Shaft Resistance, kip
End Bearing, kip
(Percent Total)
(Percent Total)
–
–
Last Re-strike Using CAPWAP
Shaft Resistance, kip
End Bearing, kip
(Percent Total)
(Percent Total)
96 (68%)a
46 (32%)a
Project
ID
Soil Type
ISU1
Mixed
ISU2
Clay
111 (89%)
14 (11%)
114 (88%)
16 (12%)
ISU3
Clay
136 (91%)
14 (9%)
130 (88%)
18 (12%)
ISU4
Clay
151 (98%)
3 (2%)
138 (90%)
16 (10%)
ISU5
Clay
187.5 (77%)
55.5 (23%)
186 (76%)
59 (24%)
ISU6
Clay
–
–
186 (88%)
25 (12%)
ISU7
Mixed
–
–
67 (89%)
8 (11%)
ISU8
Mixed
136 (84%)
26 (16%)
117(73%)
43 (27%)
ISU9
Sand
114 (72%)
44 (28%)
115 (74%)
40 (26%)
–
–
100 (85%)
18 (15%)
ISU10
Sand
– based on end of driving condition.
Shaft Resistance Distribution (kip)
0
20
40
0
EOD
BOR2
BOR4
BOR6
10
Depth Below Ground (ft)
60
BOR1
BOR3
BOR5
SLT
Clay
20
Silty Clay to Clay
Clay
30
GWT
40
Silty Clay to Clay
50
60
0
2
4
6
8
10
12
14
16
18
20
22
24
SPT N-value
Figure 5.2. SLT measured and CAPWAP estimated pile shaft resistance distributions for
test pile ISU5
66
5.3. Load Transfer Analysis Using mBST and TZPILE Program
The modified Borehole Shear Test (mBST) was used to improve the prediction of the loaddisplacement relationship and the load distribution for axially loaded friction piles in cohesive
soils using a load-transfer analysis (t-z method). Previously, empirical formulas with soil
laboratory or in-situ tests, such as the Cone Penetration Test (CPT), have been used for deriving
the t-z curves required for this analysis, but the mBST enables direct field measurement of these
curves along the soil-pile interface. Three full-scale, instrumented, static vertical load tests
conducted on steel H-piles (ISU4, ISU5 and ISU8) were used in this study. The t-z analysis was
used to model these three piles utilizing the TZPILE software. Different t-z curves were used in
the models, based on: (1) empirical correlations with CPT; and (2) direct measurements from the
mBST. When compared to the measured responses from the static vertical load tests, the mBSTbased models showed a significant improvement in the prediction accuracy compared to the
CPT-based models. The findings in this report may help to incorporate serviceability limits into
the design of deep foundations. The major findings from this study are summarized as follows:




The pile load-displacement relationship predicted using t-z curves based on empirical
correlations with CPT data (TZ-CPT) significantly overestimated the soil-pile interface
properties, the first portion of the load-displacement response, and the pile capacity by as
much as 50%
The pile load-displacement response calculated using t-z curves obtained from mBST
data (TZ-mBST) provided a close match of the slope of the first portion of the measured
load-displacement responses (i.e., the load-displacement curve before the start of
plunging) and an acceptable estimate of the pile capacity (with differences ranging from
17% to 25% for the three test sites)
Ignoring the end-bearing component (q-w curve) in the t-z analysis did not significantly
affect the results in the case of friction steel H-piles
Based on overall response predictions for the three (3) test sites, the TZ-mBST model has
proven to provide a better match of the measured SLT results when compared with the
TZ-CPT model.
Finally, the mBST is a simple and a cost effective in-situ test that captures the soil-pile interface
and can be directly used in the load-transfer analysis to simulate the load-displacement behavior
at the pile head and the load distribution along the pile length. For a more detailed description of
this study, refer to AbdelSalam (2010).
5.4. Interpretation of Push-In Pressure Cell Measurements
Lateral earth and pore water pressures, in cohesive soil layers near test piles ISU5, ISU6, ISU7
and ISU8, as well as in a cohesionless soil layer near test pile ISU10, were measured using pushin pressure cells (PCs). Two cases with respect to the ground water elevation and PCs in
cohesive soil layers were explicitly described. The first case, referring to PC1 at ISU5, was
installed approximately 23-ft (7-m) below the ground surface and above the water table, which is
at 36-ft (11-m) below ground level at this location, whilst for the second case, referring to PC3
and PC4 at ISU6, the PCs were installed approximately 33-ft (10-m) below the ground surface
and also below the water table, which lies at 15-ft (4.6-m) below ground level. The
measurements for ISU5 and ISU6 are plotted in Figure 3.17 and in Appendix B.6 respectively.
67
Similar observations were briefly described for PC1 at ISU7 (below water table) and PC4 at
ISU8 (above water table) with their measurements presented in Appendix B.6.
The initial pore water pressure recorded by PC1 at ISU5 began with a zero value. Due to the
process of PC installation that created a passive stress concentration around the PC, the initial
lateral earth pressure (σh) was slightly higher than the estimated geostatic vertical pressure (σv).
The initial pile driving had no effect on either the total lateral earth or pore water pressures.
However, when the pile toe reached the PC1 elevation, at about 23.2-ft (7-m), the lateral earth
pressure and pore water pressure increased almost instantaneously, to about 70 psi (486 kPa) and
50 psi (345 kPa) respectively. Next, the lateral earth pressure and pore water pressure reduced
immediately to about 25 psi (169 kPa) and 19 psi (130 kPa) respectively. It is important to note
that this phenomenon occurred before EOD. The pore water pressure then continued to decrease
with time even when the SLT was performed at 9 days after EOD. As expected from the
dissipation of pore water pressure, the lateral earth pressure increased slowly with time. Figure
3.17 shows that the re-strike and SLT events had insignificant effects on both pressures.
Similar observations were noticed from PC4 at ISU8, at which the lateral earth and pore water
pressures instantaneously increased, to about 45 psi (310 kPa) and 3 psi (21 kPa) respectively,
when the pile toe reached the PC4 elevation. The lateral earth pressure reduced immediately to
its initial value, while the pore water pressure reduced slightly and gradually with time.
For the second case, the PC measurements at ISU6, plotted in Appendix B.6, show both σh
values increased, to about 94 psi (640 kPa), when the pile toe reached the PC elevations. Before
the EOD, the effect of remolding from the continuous pile driving process reduced the σh value
at PC3 to a relative lower value, of 45 psi (310 kPa), than that at PC4, of 52 psi (360 kPa), which
was placed 15-in. (380-mm) further away than PC3 at a distance of 24-in. (610-mm) from ISU6.
On the other hand, the water pressure at PC3 increased to a relative higher magnitude of 15 psi
(101 kPa) when compared to 9 psi (64 kPa) at PC4. These PC measurements showed that the
PC3 water pressure did not reduce immediately; instead, it increased from the moment when the
pile toe reached the PC3 sensor to BOR3. This phenomenon can be explained by the denser
surrounding cohesive soil, indicated with a relatively high SPT N-value of 16, coupled with its
smaller measured vertical coefficient of consolidation of about 0.006 in2/min (0.039 cm2/min).
Beginning approximately 1.6 hours after EOD (i.e., at BOR4), the PC3 water pressure
logarithmically dissipated about 4 psi (30 kPa) over the period of one day and had almost
completely dissipated to its hydrostatic state in seven days, whereas the PC4 water pressure
logarithmically reduced with a smaller value of 1 psi (7 kPa).
Since PC1 at ISU7 was installed at a location about 5-ft (1.5-m) away from ISU6 (see Appendix
A) and at an elevation 6-ft (1.8-m) above PC3 and PC4 at ISU6 (see Appendix B.1), the
measurements obtained from PC1 shared similar observations. Both lateral earth and pore water
pressures increased, to about 48 psi (331 kPa) and 5.6 psi (39 kPa) respectively, when the pile
toe reached the PC1 elevation. The pore water pressure did not reduce immediately after driving
and its dissipation only began after BOR1. Unlike ISU5 and ISU8, the re-strikes and SLT events
slightly influenced the PC measurements at ISU6 and ISU7, however, the overall logarithmic
trends were not affected by these events.
68
Dissipation of pore water pressure began when the maximum pressure induced by pile driving
was developed. At least 50% of the excess pore water pressure dissipated within 10 minutes at
ISU5 and 4.8 hours at ISU6. Relating the different rate in pore water pressure dissipation, pile
resistance at ISU5 increased rapidly, to 21% within 20 minutes (BOR1), while ISU6 required a
longer time delay, of about 1.6 hours (BOR4), to reach the same percentage increase in the pile
resistance (refer to Table 4.3 and Table 4.7). The continuous logarithmic dissipation of pore
water pressure with time explains the similar pile setup trend, which is further described in
Section 5.5. Due to the presence of moisture content in cohesive soils, dissipation of pore water
pressure occurred regardless of the ground water elevation. This observation concludes that pile
setup occurs along the embedded pile length which is surrounded with cohesive soils. However,
the rate of pore water dissipation in a cohesive soil layer is dependent on its respective ground
water elevation. The results showed that a higher rate of pore water pressure dissipation was
experienced at soil layers above the water table, which led to a higher pile setup rate. In other
words, a pile embedded in a cohesive soil profile with a relatively high ground water elevation
requires a longer time to achieve the desired pile setup.
Alternatively, measurements obtained from PC4 at ISU10, installed in the cohesionless soil layer
(sand) at 10-ft (3-m) below ground, revealed that both lateral earth and pore water pressures
dissipated immediately, from the maximum values of 39.5 psi (272 kPa) and 4.5 psi (31 kPa) to
their respective initial values before EOD (see Appendix B.6). The water pressure returned to
the estimated hydrostatic pressure of 3.5 psi (24 kPa) and the lateral earth pressure remained
constantly larger than the estimated geostatic vertical pressure of 9.7 psi (67 kPa). This
observation was consistent with the minimal variation in pile resistance over time predicted
using CAPWAP during the re-strike events, as reported in Table 4.7 and re-plotted in Figure 5.6.
As such, it is concluded that pile setup does not occur in this cohesionless layer, due to the rapid
and complete dissipation of the excess pore water pressure before the EOD.
5.5. Pile Responses over Time
5.5.1 Pile Driving Resistance
Pile responses in terms of pile driving resistances at three different pile-embedded soil profiles,
clay, mixed soil and sand, were evaluated as a function of embedded pile length and time. The
pile driving resistances were referenced to the hammer blow counts, which were video-recorded
during driving, at EOD and during re-strikes, as reported in Table 4.22. Pile driving resistances
for test piles ISU5, ISU8 and ISU9, as plotted in Figure 5.3, were selected to represent the clay,
mixed soil and sand profiles respectively. Figure 5.3 shows that pile driving resistance increased
as embedded pile length accumulated during pile installation. However, due to the effect of pile
setup, with its trivial embedded pile length increment during re-strikes, the hammer blow count
of ISU5 significantly increased from 30 at EOD condition to 72 at BOR6 after 7.92 days of pile
installation (see Figure 5.3(a)). Similar phenomenon was observed at ISU8 for the mixed soil
profile in Figure 5.3(b). In contrast, ISU9, which was embedded in the sand profile, did not
experience the similar continuous increase in pile driving resistance after EOD as observed at
ISU5 and ISU8. Confirmed by similar observations from the remaining test piles, included in
Appendix D.1, it is concluded that pile setup occurs in the clay and mixed soil profiles but not in
the sand profile.
69
10
15
20
25
0
0
Blow/ft
SPT N-value
2
5
10
15
25
0
0
Blow/ft
SPT N-value
5
5
Clay
4
6
20
25
8
Silty Clay to Clay
30
Clay
10
GWT
12
35
40
14
Silty Clay to Clay
6
18
BOR4 BOR5
BOR3
60
20
GWT
25
Silty Sand to Sandy Silt
30
10
35
Sand
12
40
Clayey Silt to Silty Clay
14
16
BOR6
10
Silty Clay to Clay
8
55
EOD
5
Blow/ft
SPT N-value
10
Clay
4
50
BOR1
BOR2
16
45
0
15
Pile Penetration Below Ground (ft)
Pile Penetration Below Ground (m)
Clay
10 15 20 25 30 35
2
4
15
5
0
Sandy Silt to Clayey Silt
2
10
Pile Penetration Below Ground (m)
20
0
Silty Sand to Sandy Silt
45
Clayey Silt to Silty Clay
50
BOR2
BOR4BOR5
55
EOD
BOR1BOR3
18
15
Pile Penetration Below Ground (m)
5
0
SPT N-value
Pile Penetration Below Ground (ft)
0
SPT N-value
GWT
6
20
30
10
35
12
40
EOD
BOR1
14
45
BOR3
BOR5
BOR4
BOR6
16
BOR6
25
Sand
8
BOR2
50
55
60
18
60
65
20
65
Silty Clay to Clay
65
20
0
10 20 30 40 50 60 70 80
Hammer Blows per ft
20
0
10
20
30
Hammer Blows per ft
40
0
5
10
15
Hammer Blows per ft
(a) ISU5 for clay profile
(b) ISU8 for mixed profile
(c) ISU9 for sand profile
Figure 5.3. Pile driving resistance in terms of hammer blow count
70
20
Pile Penetration Below Ground (ft)
SPT N-value
5.5.2 Relationship Between Pile Resistance and Time
Total pile resistances (Rt) estimated using WEAP and CAPWAP, summarized in Table 4.23 and
Table 4.7 respectively, were plotted against the time (t) at when the re-strikes were performed
(see Table 4.3). Among the five soil profile input procedures used in WEAP, only the results
estimated using the Iowa Blue Book method (refer to Section 4.6.4 for detailed description) were
presented for a comparative purpose. In addition, pile resistances measured using the static load
tests, given in Table 4.24, were included to verify the relationship between pile resistance and
time. Figure 5.4 and Figure 5.5 show that the increase in total pile resistance has a logarithmic
relationship with time for both clay and mixed soil profiles, respectively. Not only do the
resistances estimated during re-strikes, using both WEAP and CAPWAP, follow the logarithmic
trend, but also the resistances measured at SLT agree with the trend. Alternatively, Figure 5.6
shows that the total resistance of test pile ISU10, embedded in sand profile, did not increase as
much as observed in the clay and mixed soil profiles, while the resistance of ISU9 decreased
with time. These results agreed with the observations described in Section 5.4 based on the
contrasting pore water pressure measurements between cohesive and cohesionless soils and
agreed with the conclusion made in Section 5.5.1.
250
Total Pile Resistance, Rt (kip)
Total Pile Resistance, Rt (kip)
250
200
150
100
ISU2 (SLT)
ISU4 (SLT)
ISU6 (SLT)
ISU3 (WEAP)
ISU5 (WEAP)
50
0
0.0001
0.01
ISU3 (SLT)
ISU5 (SLT)
ISU2 (WEAP)
ISU4 (WEAP)
ISU6 (WEAP)
1
200
150
100
ISU2 (SLT)
ISU4 (SLT)
ISU6 (SLT)
ISU3 (CAPWAP)
ISU5 (CAPWAP)
50
0
0.0001
100
Time After End of Driving, t (Day)
0.01
ISU3 (SLT)
ISU5 (SLT)
ISU2 (CAPWAP)
ISU4 (CAPWAP)
ISU6 (CAPWAP)
1
Time After End of Driving, t (Day)
(a) WEAP-Iowa Blue Book Procedure
(b) CAPWAP
Figure 5.4. Relationship between total pile resistance and time for clay profile
71
100
250
ISU7 (WEAP)
ISU8 (WEAP)
ISU7 (SLT)
ISU8 (SLT)
200
Total Pile Resistance, Rt (kip)
Total Pile Resistance, Rt (kip)
250
150
100
ISU7 (CAPWAP)
ISU8 (CAPWAP)
ISU7 (SLT)
ISU8 (SLT)
200
150
100
50
50
0
0.0001
0.01
1
0
0.0001
100
Time After End of Driving, t (Day)
0.01
1
100
Time After End of Driving, t (Day)
(a) WEAP-Iowa Blue Book Procedure
(b) CAPWAP
Figure 5.5. Relationship between total pile resistance and time for mixed soil profile
250
250
ISU9 (WEAP)
ISU10 (WEAP)
ISU9 (SLT)
ISU10 (SLT)
200
Total Pile Resistance, Rt (kip)
Total Pile Resistance, Rt (kip)
200
150
100
50
0
0.0001
0.01
1
ISU9 (CAPWAP)
ISU10 (CAPWAP)
ISU9 (SLT)
ISU10 (SLT)
150
100
50
0
0.0001
100
Time After End of Driving, t (Day)
0.01
1
Time After End of Driving, t (Day)
(a) WEAP-Iowa Blue Book Procedure
(b) CAPWAP
Figure 5.6. Relationship between total pile resistance and time for sand profile
72
100
Table 5.2 summarizes the percent increase in each pile resistance component (∆R) with reference
to its corresponding WEAP or CAPWAP estimated initial pile resistance component at EOD
(REOD) in the clay soil profile. The increases in total pile resistance, shaft resistance and end
bearing resistance are listed separately to illustrate the different effects on setup. Both shaft
resistance and end bearing increased with time after EOD. Referring to the last re-strikes of all
test piles, the increase in CAPWAP calculated shaft resistance ranged from 51% to 71% while
the end bearing resistance increased by 8% to 21%. Since the end bearing component on
average was about 16% of the total resistance, the impact of setup estimated for this component
is not significant. Furthermore, the CAPWAP pile setup estimate on shaft resistance correlated
well with the corresponding SLT measurements, in Table 5.2, that indicates 52% to 66%
increase in shaft resistance due to setup. This observation concludes that the setup largely affects
the shaft resistance of steel H-piles. Among the five test piles, ISU2 had the greatest gain in total
pile capacity and shaft resistance and ISU3 had the greatest gain in end bearing. The correlations
between pile setup and soil properties were discussed in Section 5.6. Furthermore, referring to
ISU5 as an example, the total pile resistance increased by 31% within a day after pile installation
(i.e., at BOR4) while the total increase at 7.9 days was only 38% using CAPWAP and 37% using
SLT. This observation indicated that pile resistance increased immediately and significantly
after pile installation which agreed with the rapid pore water dissipation recorded using the PC
described in Section 5.4.
Table 5.2. Percent increase in pile resistance based on CAPWAP and SLT measurements
Test
Site
ISU2
ISU3
ISU4
ISU5
ISU6
Type of
event
BOR1
BOR2
BOR3
BOR1
BOR2
BOR3
BOR4
BOR5
BOR1
BOR2
BOR3
BOR4
BOR5
BOR6
BOR1
BOR2
BOR3
BOR4
BOR5
BOR6
BOR1
BOR2
BOR3
BOR4
BOR5
BOR6
BOR7
BOR8
CAPWAP, ∆R/REOD (%)
Time
after
EOD, t
(day)
WEAP,
∆Rt/REOD
(%)
0.17
0.92
2.97
2.85E-3
7.30E-3
1.66E-2
1.11
1.96
4.05E-3
1.58E-2
0.04
0.74
1.74
4.75
5.38E-3
1.26E-2
4.78E-2
0.92
2.90
7.92
1.60E-3
4.36E-3
1.17E-2
6.71E-2
0.83
2.82
6.79
9.81
31 %
59 %
80 %
36 %
36 %
36 %
49 %
61 %
12 %
29 %
18 %
40 %
55 %
63 %
24 %
27 %
30 %
42 %
59 %
79 %
-4 %
3%
10 %
20 %
43 %
57 %
73 %
82 %
Total
44 %
61 %
61 %
4%
6%
31 %
45 %
49 %
4%
7%
19 %
33 %
42 %
51 %
7%
21 %
24 %
31 %
32 %
38 %
0%
3%
2%
22 %
29 %
36 %
46 %
46 %
End
Bearing
Shaft
52 %
71 %
71 %
4%
5%
33 %
49 %
54 %
1%
5%
19 %
36 %
46 %
57 %
9%
30 %
33 %
41 %
43 %
51 %
0%
2%
1%
24 %
32 %
40 %
51 %
51 %
6%
12 %
13 %
10 %
16 %
22 %
21 %
21 %
17 %
17 %
15 %
14 %
13 %
14 %
1%
2%
3%
7%
7%
8%
0%
6%
7%
11 %
12 %
15 %
17 %
16 %
73
SLT
∆Rt/REODWEAP (%)
∆Rt/REOD-CAPWAP (%)
Total
Total
Shaft
End
Bearing
62 %
55 %
66 %
3%
84 %
52 %
60 %
3%
62 %
51 %
n/a
n/a
70 %
37 %
52 %
3%
54%
47 %
n/a
n/a
To investigate the contribution of shaft resistance and end bearing components to pile setup in
clay profile, the shaft resistance and end bearing components estimated using CAPWAP are
plotted against time (t), as shown in Figure 5.7. The reasonably good fit of trend lines reveals
that both shaft resistance and end bearing components increase logarithmically with time.
However, the increase in shaft resistance is larger than that in the end bearing at a given time,
indicated by the steeper slope of the shaft resistance component. Hence, it is acknowledged that
pile setup in clay profile results predominantly from the shaft resistance with minimal input from
the end bearing, as similarly described in the previous paragraph. For the mixed soil profile,
Figure 5.8 similarly shows that the shaft resistance generally follows the logarithmic trend while
the end bearing randomly deviates somewhat along the logarithmic trend line. Unlike the clay
profile shown in Figure 5.7, the decrease in shaft resistance and the increase in end bearing with
time at ISU8 indicate that pile setup is contributed mostly from the end bearing. Compared with
the clay profile, this different observation might have been complicated by the presence of
cohesionless soil layers (layers 2, 4, and 6 as shown in Appendix B.1) along about 40% of the
57.21-ft (17.44-m) embedded pile length, while the pile toe was fully embedded in a cohesive
soil layer (classified as CL in accordance with the USCS). The inconsistent observations
between ISU7 and ISU8 and the limited field tests available in the mixed soil profile pose
challenges in establishing a general conclusion for pile setup in this profile.
Shaft Resistance (kip)
250
200
100
ISU2 (SLT-Shaft)
ISU3 (SLT-Shaft)
ISU4 (SLT-Shaft)
ISU5 (SLT-Shaft)
ISU6 (SLT-Shaft)
ISU2 (CAPWAP-Shaft)
ISU3 (CAPWAP-Shaft)
ISU4 (CAPWAP-Shaft)
ISU5 (CAPWAP-Shaft)
ISU6 (CAPWAP-Shaft)
ISU2 (SLT-End)
ISU3 (SLT-End)
ISU4 (SLT-End)
ISU5 (SLT-End)
ISU2 (CAPWAP-End)
ISU3 (CAPWAP-End)
ISU4 (CAPWAP-End)
ISU5 (CAPWAP-End)
ISU6 (CAPWAP-End)
90
80
Pile End Bearing (kip)
300
150
100
70
60
50
40
30
20
50
10
0
0.0001
0.01
1
0
0.0001
100
Time After End of Driving, t (Day)
0.01
1
Time After End of Driving, t (Day)
(a) Shaft Resistance vs Time
(b) End Bearing vs Time
Figure 5.7. Relationship between resistance components and time for clay profile
74
100
200
100
ISU7 (CAPWAP-End)
ISU7 (CAPWAP-Shaft)
ISU8 (CAPWAP-Shaft)
ISU8 (SLT-Shaft)
90
ISU8 (CAPWAP-End)
80
ISU8 (SLT-End)
Pile End Bearing (kip)
Shaft Resistance (kip)
150
100
70
60
50
40
30
50
20
10
0
0.0001
0.01
1
0
0.0001
100
Time After End of Driving, t (Day)
0.01
1
100
Time After End of Driving, t (Day)
(a) Shaft Resistance vs Time
(b) End Bearing vs Time
Figure 5.8. Relationship between resistance components and time for mixed soil profile
5.6. Pile Setup in Clay Profile
The aforementioned observations confirmed the logarithmic relationship between pile setup and
time in the clay profile. When accounted for accurately, integration of pile setup will lead to
more cost-effective design as it will reduce the number of piles and/or pile length in the clay
profile. However, there are several limitations associated with the existing pile setup knowledge,
and there are currently no methods available to confidently account for the effects of pile setup in
foundation designs. These limitations arise from the lack of: a) sufficient and detailed dynamic
and static field test data as a function of time for accurate pile setup evaluation; b) detailed
subsurface investigations and monitoring of soil stresses to quantify pile setup (Komurka et al.
2003); and c) a systematic reliability-based method to account for pile setup in the LRFD
approach. The extensive field tests carried out herein involved detailed pile setup measurements,
using WEAP and CAPWAP, as well as soil investigations. These tests provide the opportunity
to: 1) assess the influence of various soil properties on pile setup, as discussed in Section 5.6.1;
and 2) develop two pile setup quantification methods in terms of commonly measured SPT Nvalue and/or CPT determined coefficient of consolidation, as discussed in Section 5.6.2. Along
with the five field test results, twelve data points from the PILOT database were selected to
validate the proposed pile setup quantification methods established for WEAP, discussed in
Section 5.6.3. Since the PILOT database does not contain any PDA records for CAPWAP
analyses, only the five field tests were used in validating the pile setup methods established for
CAPWAP. To incorporate pile setup into LRFD, a new calibration procedure using the
reliability theory was established in Section 5.6.4.
75
5.6.1 Influence of Various Soil Properties on Pile Setup
Since the pile setup largely increases the shaft resistance, a detailed correlation study between
soil properties and percent increase in shaft resistance (∆R/REOD) was performed. For illustrative
purposes, the correlation study of ISU5 has been explicitly described, whilst studies for the
remaining four test piles are included in Appendix D.4. The percent increase in shaft resistance
calculated for ISU5 using CAPWAP, between EOD and the last re-strike, was plotted along the
embedded pile length, in Figure 5.9, together with the measured vertical coefficient of
consolidation (Cv), SPT N-value, over consolidation ratio (OCR), soil compressibility index (Cc),
and plasticity index (PI). Since the horizontal coefficient of consolidation (Ch) was not
successfully measured at ISU5 due to the time required to achieve 50% pore water pressure
dissipation, it can be related to the SPT N-values as shown in Figure 5.10. A similar shaft gain
distribution of ∆R/REOD for the SLT, the percent difference between the measured shaft
resistance from SLT at 9 days after EOD and the CAPWAP calculated shaft resistance at EOD,
is also included in Figure 5.9 for comparative purposes. It is interesting to note that the
distributions of percent increase in shaft resistance (∆R/REOD) for both CAPWAP and SLT have
a similar trend, although the magnitudes are sometimes significantly different, which can be
attributed to the standard CAPWAP signal matching procedure that uses constant damping and
quake values to achieve a best match.
Percent Increase In Shaft Resistance Distribution (%)
0%
5%
10%
15%
20%
25%
0
2
Cv=0.017 in2/min
OCR=4.5; Cc=0.187
30%
0
Shaft Gain (CAPWAP-8 days)
Shaft Gain (SLT-9 days)
SPT N-value
Plasticity Index
Depth Below Ground (m)
4
Low plasticity
Clay (CL)
6
8
Cv=0.014 in2/min
OCR=1.28; Cc=0.256
5
10
15
20
25
30
10
GWT
Cv=0.008 in2/min
OCR=1.0; Cc=0.124
12
Low Plasticity
Clay with Sand (CL)
14
35
40
45
Depth Below Ground (ft)
-5%
50
16
55
18
60
65
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40
SPT N-value or Plasticity Index (%)
Figure 5.9. Relationship between soil properties and increase in shaft resistance for ISU5
76
0.16
CPT (Ch)
One-dimensional test (Cv)
0.14
0.12
0.14
0.12
0.10
0.10
Ch = 0.4928N-2.081
R² = 0.7005
0.08
0.08
0.06
0.06
0.04
0.04
0.02
0.02
0.00
Vertical Coefficient of Consolidation, Cv (in2/min)
Horizontal Coefficient of Consolidation, Ch (in2/min)
0.16
0.00
0
2
4
6
8
10 12 14 16 18 20 22 24 26 28
SPT N-value
Figure 5.10. Correlations of both vertical and horizontal coefficients of consolidation with
SPT N-values
The SLT-based shaft gain distribution, shown in Figure 5.9, illustrates that the ∆R/REOD
increased by about 5% in the 16-ft (5-m) thick top soil layer, which was characterized with
relatively large Cv values, ranging between 0.014 in2/min (0.089 cm2/min) and 0.017 in2/min
(0.107 cm2/min), and small SPT N-values, ranging between 6 and 9. This ∆R/REOD continued to
reduce to a depth of around 36-ft (11-m) from ground surface, where the surrounding cohesive
soil layer has the smallest Cv of 0.008 in2/min (0.051 cm2/min) and the highest SPT N-value of
22. With the combined effects of the overburden pressure and the reduction in SPT N-value,
from 22 to 13, below the 36-ft (11-m) depth, the ∆R/REOD indicated a peak increase of about
25%. This observation suggests a direct relationship between pile setup along the shaft and the
coefficient of consolidation, plus an inverse relationship between pile setup and SPT N-value (or
a direct correlation with the horizontal coefficient of consolidation, as indicated by Figure 5.10).
Besides comparing with SPT N-value and coefficient of consolidation, pile setup was also
compared with other soil properties, including over consolidation ratio (OCR), compressibility
index (Cc) and plastic index (PI). Figure 5.9 reveals an inverse relationship between the
measured PI and the ∆R/REOD. For instance, within the cohesive soil layers with low PI values,
of 5.6% and 8.6% at 10-ft (3-m) and 47-ft (14-m) respectively, the shaft resistances increased.
Hence, a pile embedded in a cohesive soil with low PI will experience a large ∆R/REOD at any
given time. Furthermore, Zheng et al. (2010) concluded that a low compressive cohesive soil
with a small Cc value dissipated the excess pore water pressure faster. Relating this conclusion
to pile setup, this means Cc value should have an inverse relationship with ∆R/REOD, however,
77
Figure 5.9 reveals no such relationship, especially at the 11-m (36-ft) depth where ∆R/REOD
reduced despite having the lowest Cc of 0.124.
To further expand upon the observations presented above using data from ISU5, the percent
increase in total pile resistance, shaft resistance and end bearing estimated for all five test piles
using CAPWAP were compared with weighted average Ch, Cv, PI and SPT N-values, allowing
variation of soil thicknesses along the embedded pile length to be included. For soil layers
where the CPT dissipation test was not conducted or the 50% consolidation was not achieved,
the horizontal coefficient of consolidation (Ch) was estimated using the SPT N-value, based on
the correlation developed from field test results presented in Figure 5.10. Table 5.3 summarizes
the findings together with the weighted average soil properties along the pile shaft and near the
pile toe for each test site, whilst Figure 5.11 gives a graphical representation of the same data for
each of the soil variables affecting pile setup, at approximately 1 day after EOD for all sites.
Table 5.3. Average soil properties along pile shaft and near pile toe
Test Site
ISU2
ISU3
ISU4
ISU5
ISU6
SPT N-value
Shaft
Toe
5
4
8
10
10
13
12
13
14
22
Ch (in2/min)
Shaft
Toe
0.0322
0.0276
0.0070
0.0040
0.0087
0.0023
0.0043
0.0023
0.0034
0.0008
Cv (in2/min)
Shaft
Toe
0.0195
0.0175
0.0158
0.0150
0.0146
0.0155
0.0140
0.0132
0.0132
0.0143
PI (%)
Shaft
14.86
9.95
15.44
18.17
9.22
Toe
28.40
8.15
13.06
22.33
7.43
At 1 day after EOD, Figure 5.11(a) shows that the increase in total pile resistance and shaft
resistance is inversely proportional to SPT N-value for all five piles. Similarly, Figure 5.11(b)
and (c) show that total pile resistance and shaft resistance of a pile increase linearly with the Ch
and Cv values, respectively. However, Figure 5.11(d) shows that total pile resistance and shaft
resistance increase with PI between 8% and 12%, which mainly represent the sandy low
plasticity clay soils surrounding test piles ISU3 and ISU6 (see Appendix B). However, the
continuous increase in PI above 12%, which represents the mostly low plasticity clay soils, with
a higher affinity for water, at the test sites of ISU2, ISU4 and ISU5, results in a reduction of both
total pile resistance and shaft resistance. Although the end bearing components were included in
these figures, no clear correlations between the soil properties and the end bearing component
are evident, as expected. This is largely due to relatively large deviations in the data resulting
from: a) smaller contributions of the end bearing to total pile resistance; and b) small errors in
the estimation of shaft resistance causing larger error to the end bearing components. The
insignificance of the impact of the end bearing has also been confirmed by the comparable trends
observed for both the shaft resistance and total pile resistance.
Most importantly, Figure 5.11 strongly supports the prospect of using routine in-situ (i.e., SPTs
and/or CPTs with pore water pressure dissipation tests) and/or laboratory soil testing procedures
(i.e., one-dimensional consolidation tests) to quantitatively estimate pile setup for use in the
LRFD approach. Detailed laboratory soil classifications, PI estimations and soil layer
identifications are also an essential part of our recommended systematic approach for routine and
accurate pile setup estimations within the LRFD framework.
78
80%
Total Capacity
Shaft Resistance
End Bearing
80%
Percent Gain In Pile Capacity at t=1 day After
EOD (∆R/REOD)
Percent Gain In Pile Capacity at t=1 day After
EOD (∆R/REOD)
90%
Best fit line for
total capacity
70%
Best fit line for
shaft resistance
60%
50%
40%
Best fit line for
end bearing
30%
20%
10%
(a)
0%
0
70%
60%
50%
40%
30%
20%
10%
0%
5
10
15
20
Total Capacity
Shaft Resistance
End Bearing
(b)
0
25
0.01
(a) Relation with SPT N-value
0.04
(b) Relation with Ch
90%
90%
Total Capacity
Shaft Resistance
End Bearing
Percent Gain In Pile Capacity at t=1 day After
EOD (∆R/REOD)
Percent Gain In Pile Capacity at t=1 day After
EOD (∆R/REOD)
0.03
Horizontal Coefficient of Consolidation
Ch (in2/min)
SPT N-value
80%
0.02
70%
60%
50%
40%
30%
20%
10%
Total Capacity
Shaft Resistance
End Bearing
80%
70%
60%
50%
40%
30%
20%
10%
(d)
0%
0%
0.01
0.015
0.02
0.025
Vertical Coefficient of Consolidation Cv
(in2/min)
4
8
12
16
20
24
28
32
Plasticity Index, PI (%)
(c) Relation with Cv
(d) Relation with PI
Figure 5.11. Relationships between percent gain in pile capacity and (a) SPT N-value, (b)
Ch, (c) Cv, and (d) PI, estimated at a time of 1 day after EOD for all sites
79
5.6.2 Development of Pile Setup Analytical Quantification Methods
Using the field test results of steel H-piles driven in the clay soil profile, two analytical methods
were established to quantify pile setup. Although existing methods found in literature, such as
Skov and Denver (1988), have been utilized for decades, they require inconvenient re-strikes
during construction and rarely correlate with any soil properties, even though these properties
significantly influence the pile setup. To account for these limitations, the proposed methods
were developed in terms of soil properties that can be measured using in-situ soil investigations,
such as SPT and CPT. For convenient practical applications, the methods utilize the initial pile
resistance estimated at the EOD condition (REOD) using either WEAP or CAPWAP. The first
method described (CPT & SPT based setup method) incorporates the average SPT N-value (Na)
and horizontal coefficient of consolidation (Ch) determined from CPT to represent the
surrounding soils, and employs an equivalent pile radius to represent the pile geometry. The
average SPT N-value is calculated by weighting the measured N-value (Ni) at each cohesive soil
layer, i, along the pile shaft by its thickness (ℓi) for the total number, n, of cohesive layers
situated along the embedded pile length, simply expressed as:
∑
∑
(5-2)
To further simplify the pile setup estimation for routine practical applications, the second method
described (SPT based setup method) considers only the commonly used average SPT N-value.
When total pile resistance (Rt) and time (t), as shown in Figure 5.4, are normalized by initial pile
resistance (REOD) and initial time (tEOD) at EOD condition respectively, a linear relationship
between normalized pile capacity (Rt/REOD) and logarithmic normalized time (Log10(t/tEOD)) for
each test pile is observed (see Figure 5.12 (a) and (b)), based on CAPWAP and WEAP analyses.
To correct pile resistance gain resulting from additional pile penetrations during re-strikes,
normalized pile resistance was multiplied with normalized pile embedded pile length (LEOD/Lt).
In order to satisfy the logarithmic relationship and to consider the immediate gain in pile
resistance measured after EOD, the time at EOD (tEOD) was assumed to be 1 minute (0.000693
day).
Each linear best fit line was generated using a linear regression analysis based on re-strike
results, as indicated by open markers. Most linear lines fit reasonably well with the results,
indicated with good coefficients of determination (R2). For a comparative purpose, static load
test results, indicated by filled markers, were also included. The slope (C) of each linear best fit
line describes the rate of pile resistance gain, i.e., a linear line with a larger slope indicates a
higher percentage of pile resistance gain or provides a larger normalized pile resistance (Rt/REOD)
at a given time. It is important to recognize that the magnitude of the slope (C) is not a unique
constant for all piles but its variation is dependent on the surrounding cohesive soil properties.
The equation for the linear best fit lines can be expressed as:
[
(
80
)
](
)
(5-3)
5.6.2.1 CPT & SPT based setup method
It is evident from the field test results (see Figure 5.7) that pile setup mostly occurs along a pile
shaft, hence, only the cohesive soil layers along the pile shaft are considered. Ng (2011) derived
that the pile setup rate (C) can be expressed as:
(
)
(5-4)
where
= consolidation factor (see Table 5.4), min.-1;
= remolding recovery factor (see Table 5.4);
= horizontal coefficient of consolidation as described in Section 5.2, in2/min.;
= average SPT N-value given by Eq. (5-2); and
= equivalent pile radius, in.
fc
fr
Ch
Na
rp
Using the pile setup rate (C) determined from Figure 5.12, the relationships between the pile
setup rate and measured soil parameters (SPT N-value and Ch), summarized in Table 5.3, were
plotted (see Figure 5.13) to evaluate the fc and fr factors for CAPWAP and WEAP (using Iowa
Blue Book as soil profile input method for illustrative purposes). The fc and fr factors are
tabulated in Table 5.4 together with the coefficients of determination (R2), which indicate the
accuracy of future pile setup rate predictions using Eq. (5-4). This clearly demonstrates that pile
setup rates estimated using CAPWAP will provide a better accuracy than WEAP estimates.
1.8
ISU2
ISU3
ISU4
ISU5
ISU6
ISU2 (SLT)
ISU3 (SLT)
ISU4 (SLT)
ISU5 (SLT)
ISU6 (SLT)
1.7
(Rt/REOD)×(LEOD/Lt)
1.6
1.5
1.4
Test Pile = Slope; (R2)
ISU2 = 0.1669; (0.98)
ISU3 = 0.1212; (0.89)
ISU4 = 0.1062; (0.93)
ISU5 = 0.0884; (0.87)
ISU6 = 0.0923; (0.93)
1.3
1.2
1.1
1.0
R2 = coefficient of determination
0.9
0
1
2
3
Log10(t/tEOD)
(a) Based on CAPWAP analysis
81
4
5
1.8
ISU2
ISU3
ISU4
ISU5
ISU6
ISU2 (SLT)
ISU3 (SLT)
ISU4 (SLT)
ISU5 (SLT)
ISU6 (SLT)
1.7
(Rt/REOD)×(LEOD/Lt)
1.6
1.5
1.4
Test Pile = Slope; (R2)
ISU2 = 0.1758; (0.91)
ISU3 = 0.1565; (0.32)
ISU4 = 0.1417; (0.92)
ISU5 = 0.1612; (0.90)
ISU6 = 0.1471; (0.89)
1.3
1.2
1.1
1.0
R2 = coefficient of determination
0.9
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Log10(t/tEOD)
(b) Based on WEAP analysis using Iowa Blue Book as soil profile input method
Figure 5.12. Linear best fit lines of normalized pile resistance and logarithmic normalized
time
0.22
CAPWAP
WEAP-IABB
0.2
Pile Setup Rate (C)
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0
0.0005
0.001
0.0015
0.002
0.0025
Ch/Na rp2
Figure 5.13. Correlation between pile setup rate (C) and soil parameters with pile radius
82
Table 5.4. The consolidation (fc) and remolding recovery (fr) factors
Method
CAPWAP
WEAP-ST
WEAP-SA
WEAP-DRIVEN
WEAP-Iowa Blue Book
WEAP-Iowa DOT
Consolidation Factor, fc
(min.-1)
39.048
19.565
13.780
13.590
12.889
15.497
Remolding Recovery
Factor, fr
0.088
0.155
0.150
0.149
0.148
0.147
Coefficient of
Determination, R2
0.95
0.39
0.65
0.70
0.60
0.60
5.6.2.2 SPT based setup method
In order to simplify the pile setup estimation during designs based on the commonly used SPT,
the pile setup rates determined, from Figure 5.12, are directly compared with the corresponding
average SPT N-values, given in Table 5.3. Figure 5.14 shows best fitted power-function
relationships between pile setup rates and SPT N-values. More generally, these relationships can
be expressed as:
(5-5)
where
a
b
Na
= method dependent scale factor (see Table 5.5);
= method dependent concave factor (see Table 5.5); and
= average SPT N-value given by Eq. (5-2).
The a and b factors are tabulated in Table 5.5 together with the coefficients of determination
(R2), which indicate the accuracy of future pile setup rate predictions using Eq. (5-5). Figure
5.14 shows that the increase in pile resistance is inversely proportional to SPT N-values. Hence,
a pile embedded in a denser clayey soil represented with a higher average SPT N-value
experiences a smaller gain in resistance. It is clearly shown that pile setup rate will be best
estimated using CAPWAP. Among the five different soil profile input procedures used in
WEAP, Iowa Blue Book procedure, which resulted in the highest R2 of 0.52, is recommended for
the total pile resistance (Rt) estimation using Eq. (5-6), which was derived by substituting Eq.
(5-5) into Eq. (5-3). It is important to recognize in the case for WEAP that the CPT&SPT based
method gives a better pile setup prediction than the SPT based method.
[
(
(
)
83
)
](
)
(5-6)
0.2
CAPWAP
WEAP-IABB
0.18
Pile Setup Rate (C)
0.16
0.14
0.12
0.1
0.08
0.06
0
2
4
6
8
10
12
14
16
18
Average SPT N-Value, Na
Figure 5.14. Correlation between pile setup rate (C) and average SPT N-value
Table 5.5. Scale (a) and concave (b) factors
Method
a
b
CAPWAP
WEAP-ST
WEAP-SA
WEAP-DRIVEN
WEAP-Iowa Blue Book
WEAP-Iowa DOT
0.432
0.243
0.217
0.214
0.215
0.246
0.606
0.168
0.141
0.136
0.144
0.192
Coefficient of
Determination, R2
0.97
0.24
0.47
0.48
0.52
0.26
To provide pile designers a quick and convenient approach to estimate total pile resistance
including setup resistance using either WEAP (Iowa Blue Book procedure) or CAPWAP, Eq.
(5-6) was transformed into pile setup design charts in terms of corrected normalized pile
resistance ((Rt/REOD)×(LEOD/L)) based on a range of average SPT N-value (Na), between 1 and
50, and a time lapsed (t), at days 1, 3, 5, 7, 14, 21 and 30 after EOD, as plotted in Figure 5.15.
84
2.1
1 day
5 days
14 days
30 days
2
1 day
5 days
14 days
30 days
2.9
t
0.215 log10 (
)
Rt LEOD
0.000694
(
)(
)=
+1
0.144
(Na )
REOD
L
2.5
1.8
1.7
1.6
3 days
7 days
21 days
t
0.432 log10 (
)
Rt
LEOD
0.000694 + 1
(
)(
)=
0.606
(Na )
R EOD
L
2.7
(Rt/REOD)×(LEOD/L)
1.9
(Rt/REOD)×(LEOD/L)
3.1
3 days
7 days
21 days
2.3
2.1
1.9
1.7
1.5
1.5
1.4
1.3
1.1
1.3
1
8
15 22 29 36 43
Average SPT N-value, Na
1
50
8
15 22 29 36 43
Average SPT N-value, Na
50
(a) WEAP (Iowa Blue Book)
(b) CAPWAP
Figure 5.15. Pile setup design charts for WEAP and CAPWAP
Although pile setup is estimated at a specified time, for example 7 days, after EOD during
design, the estimated pile setup can be optionally verified during construction before the
specified time. Verification of expected pile setup at 7 days is performed by comparing the pile
resistance estimated using either WEAP or CAPWAP during re-strikes with the pile setup site
verification charts given in Figure 5.16. Because pile re-strike is considered as an inconvenient
construction practice, which is generally performed within a short time after pile installation, pile
setup site verification charts are a more convenient means to confirm the pile setup estimated
during design. For instance, referring to Figure 5.16(a), the pile resistance ratio of 1.55
measured using WEAP from a re-strike at 2 days after EOD (represented by Line A) coincides
with a dashed line that corresponds to an average SPT N-value of 8. Following along the same
dashed line, the pile resistance ratio of 1.65 (or 65% increase in pile resistance) is determined
from the chart as occurring at 7 days after EOD (represented by Line B). Finally, the determined
65% increase in pile resistance can be verified against the initially estimated setup resistance, so
the amount of expected setup is ensured early before the design setup time of 7 days.
85
1.95
1.85
Na = 5
Na = 8
Na = 10
Na = 15
Na = 20
Na = 30
Na = 40
Na = 50
1.75
(Rt/REOD)×(LEOD/L)
1.70
1.85
1.75
(Rt/REOD)×(LEOD/L)
1.80
Na = 5
Na = 8
Na = 10
Na = 15
Na = 20
Na = 30
Na = 40
Na = 50
1.65
1.60
1.55
1.65
1.55
1.45
1.35
1.50
1.25
1.40
Line B
Line A
1.45
1.15
1.05
1.35
0
2
4
6
8
10 12
Time after EOD (Day)
0
14
2
4
6
8
10 12
Time after EOD (Day)
14
(a) WEAP (Iowa Blue Book)
(b) CAPWAP
Figure 5.16. Pile setup site verification charts for WEAP and CAPWAP
5.6.3 Pile Setup Validation
To validate the proposed pile setup quantification methods based on WEAP, twelve data points
with piles embedded in the clay profile were selected from PILOT, as listed in Table 5.6, along
with the recently completed five field tests. Since PILOT contains no PDA record, only the field
tests were used in the validation of the pile setup methods based on CAPWAP. Based on the
calculated average soil parameters (Na and/or Ch) the total pile resistance (Rt), including pile
setup resistance, was computed using the CPT&SPT based setup method (Eq. (5-3) and Eq.
(5-4)) and SPT based setup method (Eq. (5-6)) for both CAPWAP and WEAP, as listed in Table
5.7. To illustrate the effect of pile setup, pile resistances estimated at EOD condition (i.e.,
without considering pile setup) and pile resistances estimated at the time of load tests were
compared with the measured pile resistances using static load tests, as shown in Figure 5.17.
When considering pile setup effect using the two proposed methods for CAPWAP, Figure
5.17(a) illustrates that the mean values (μ) shift towards unity, from 1.483 to 0.978 and 0.995,
and the standard deviations (StDev or δ) reduce from 0.069 to 0.052 and 0.058 for CPT&SPT
based setup method and SPT based setup method, respectively. Similar results are observed for
setup methods using WEAP, as illustrated from Figure 5.17(b). This clearly shows that the
proposed pile setup methods have adequately and consistently predicted the increase in pile
resistances at the given time when the corresponding measured values were taken. This
statistical assessment validates the proposed pile setup methods. Additional validations were
documented in Ng (2011).
86
Table 5.6. Summary of the twelve data records from PILOT
Project
ID
County in
Iowa
Pile
Type
Pile
Penetration
(ft)
Hammer
Type
Soil Profile
Description
Average SPT
N-value, Na
Average
Ch
(in2/min)
Time
After
EOD, t
(day)
SLT Measured
Pile Resistance
at Time t (kip)
WEAP-IABB
Estimated Pile
Resistance at
EOD (kip)
6
12
42
44
51
57
62
63
64
67
102
109
Decatur
Linn
Linn
Linn
Johnson
Hamilton
Kossuth
Jasper
Jasper
Audubon
Poweshiek
Poweshiek
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 12 × 53
53
23.78
23.5
36.5
29.5
57
45
63
71
32
43
51
Gravity #732
Kobe K-13
Kobe K-13
Delmag D-22
Kobe K-13
Gravity #2107
MKT DE-30B
Gravity
Gravity
Delmag D-12
Gravity #203
Delmag D-12
Glacial clay
Glacial clay
Glacial clay
Sandy silty clay
Silt/glacial clay
Glacial clay
Glacial clay
Silt on glacial clay
Silt on glacial clay
Glacial clay
Silt/glacial clay
Glacial clay
14.47
29.90
22.20
22.34
40.00
9.77
36.05
8.32
10.52
20.00
16.45
17.36
0.00631
0.00045
0.00147
0.00083
0.00022
0.00469
0.00279
0.00665
0.00479
0.00094
0.00620
0.00204
3
5
5
5
3
4
5
2
1
4
8
3
118
204
82
136
190
168
100
66
122
140
130
176
71
155
85
94
128
94
76
59
71
121
84
147
Table 5.7. Summary of the estimated pile resistance including setup
Project ID
6
12
42
44
51
57
62
63
64
67
102
109
ISU2
ISU3
ISU4
ISU5
ISU6
Pile Resistance Based on SPT & CPT (Eq. 5-3 & Eq. 5-4) (kip)
CAPWAP
WEAP-Iowa Blue Book
109
243
133
134
197
146
Not Available
119
90
104
188
135
226
139
136
153
150
150
162
252
237
208
238
87
Pile Resistance Based On SPT (Eq. 5-6) (kip)
CAPWAP
WEAP-Iowa Blue Book
108
234
130
144
187
148
Not Available
113
91
105
184
134
223
136
132
154
144
149
159
247
231
198
229
Histogram of Pile Resistance Ratio for CAPWAP
Normal Distribution
1.0
8
1.48
Conditions
CAPWAP(EOD)
CAPWAP(EOD+Setup-CPT&SPT)
CAPWAP (EOD+Setup-SPT)
7
Density
6
Mean StDev N
1.483 0.06983 5
0.9781 0.05222 5
0.9957 0.05831 5
5
4
3
2
1
0
0.9
1.0
1.1
1.2
1.3
1.4
1.5
Ratio Between Measured and Estimated Pile Resistance
(a) CAPWAP
1.6
Histogram of Pile Resistance Ratio for WEAP (Iowa Blue Book Procedure)
Normal Distribution
3.0
1.0
1.47
Conditions
WEAP(EOD)
WEAP (EOD+Setup-CPT&SPT)
WEAP (EOD+Setup-SPT)
2.5
Mean
1.472
0.9234
0.9364
Density
2.0
StDev
0.2545
0.1514
0.1471
N
17
17
17
1.5
1.0
0.5
0.0
0.50
0.75
1.00
1.25
1.50
1.75
Ratio Between Measured and Estimated Pile Resistance
(b) WEAP based on Iowa Blue Book soil input procedure
Figure 5.17. Pile setup comparison and validation
88
2.00
Following the validation of the proposed pile setup methods, the confidence of the methods in
terms of the pile resistance ratio (Rm/Rt) at different confidence intervals can be expressed as:
(
)
√
(5-7)
(
)
√
where
μ = mean value of the pile resistance ratio;
z = standard normal parameter based on a chosen percent of confidence interval (CI);
δ = standard of deviation of the pile resistance ratio; and
n = sample size.
Using the statistical parameters (μ, δ and n) calculated in Figure 5.17, the upper and lower limits
of the population mean values of the pile resistance ratios for 80%, 85%, 90%, 95%, and 98%
confidence intervals (CIs) are calculated, using Eq. (5-7), and plotted in Figure 5.18 (a) and (b)
for the CPT & SPT based and SPT based pile setup methods respectively. Figure 5.18 shows
that the upper limits increase and the lower limits decrease with increasing CIs from 80% to
98%. In an attempt to determine the amount of pile setup that can be confidently applied directly
to production piles in the State of North Carolina, Kim and Kreider (2007) suggested the use of
98% and 90% CIs for individual piles and pile groups with redundancy, respectively, which were
assumed based on their field observations. Applying this similar recommendation in the case of
an individual pile by considering a 98% CI, the pile resistance ratio for WEAP ranges between
0.85 and 1.02 (refer to Figure 5.18 (b) for an illustrative purpose). In other words, there is 98%
confidence that the SPT based pile setup method when used in conjunction with WEAP will
predict the Rt with an error falling between -17.2% and 1.9%. Similarly, in the case of a pile
group foundation considering a 90% CI, the proposed SPT based pile setup when used in
conjunction with WEAP, the error will fall between -13.9% and -0.5%. The anticipated errors of
the pile setup methods at various confidence levels are summarized in Table 5.8. It is generally
observed that the range of errors is smaller for pile setup methods used in conjunction with
CAPWAP than those with WEAP.
Table 5.8. Anticipated errors of the pile setup methods at various confidence levels
Confidence
Level
80
90
98
Anticipated Errors (%)
SPT & CPT Based Setup Method
SPT Based Setup Method
CAPWAP
WEAP-Iowa Blue Book
CAPWAP
WEAP-Iowa Blue Book
-5.5% to 0.8%
-14.2% to -3.1%
-4% to 2.8%
-12.2% to -1.8%
-6.4% to 1.7%
-15.9% to -1.6%
-4.9% to 3.8%
-13.9% to -0.5%
-8.2% to 3.1%
-19.3% to 0.9%
-7% to 5.3%
-17.2% to 1.9%
89
Ratio of Measured and Predicted Pile Resistance
1.15
Mean (CAPWAP)
Upper Bound (CAPWAP)
Lower Bound (WEAP-IA BB)
1.10
Lower Bound (CAPWAP)
Mean (WEAP-IA BB)
Upper Bound (WEAP-IA BB)
1.05
1.032
1.017
1.008
1.00
1.009
0.984
0.970
0.95
0.948
0.940
0.924
0.90
0.876
0.85
0.863
0.838
0.80
80
85
90
Confidence Interval, CI (%)
95
98
100
(a) CPT & SPT based pile setup method
Ratio of Measured and Predicted Pile Resistance
1.15
Mean (CAPWAP)
Upper Bound (CAPWAP)
Lower Bound (WEAP-IA BB)
1.10
Lower Bound (CAPWAP)
Mean (WEAP-IA BB)
Upper Bound (WEAP-IA BB)
1.056
1.05
1.00
1.039
1.029
1.019
0.995
0.982
0.962
0.953
0.95
0.90
0.935
0.891
0.878
0.853
0.85
0.80
80
85
90
Confidence Interval, CI (%)
(b) SPT based pile setup method
Figure 5.18. Pile setup confidence levels
90
95
98
100
5.6.4 LRFD Calibration for Pile Setup
Although pile setup has been systematically quantified using the aforementioned proposed
methods, the setup quantification has its own uncertainties resulting from in-situ measurements
of soil properties and the semi-empirical approach adapted for the effects of setup. To
incorporate such a pile setup estimate in LRFD satisfactorily, it should be realized that the
impact of the uncertainties associated with the initial pile resistance at EOD (REOD), estimated
using the dynamic analysis methods, and the pile setup resistance (Rsetup), estimated using the
proposed methods, are different and they should be accounted for simultaneously to reach the
same target reliability index. While ensuring that the reliability theory based LRFD framework
is adequately followed in this process, it also enables incorporation of two resistance factors: one
for the initial pile resistance and other for the pile setup resistance. In order to provide a general
and closed-form solution, the derivation of the resistance factors for pile setup follows the First
Order Second Moment (FOSM) method. To illustrate this, the following evaluation is based on
the proposed SPT based pile setup method using Eq. (5-6) for WEAP based on the Iowa Blue
Book soil input procedure.
In order to evaluate the uncertainties associated with initial pile resistance at EOD and setup,
twelve data records from PILOT, as listed in Table 5.6, along with the five field tests were used.
To compare the various sources of uncertainties in terms of coefficient of correlation (COVR),
two different resistance ratio estimators (RRE) for EOD condition (Rm-EOD/Re-EOD) and for setup
(Rm-setup/Re-setup), based on the measured (Rm) and estimated (Re) pile resistances, were calculated,
as listed in Table 5.9. Since pile resistances were measured using SLT at time (t) after EOD, the
measured pile resistances at EOD (Rm-EOD) for the data points from PILOT were adjusted using
the SPT based pile setup Eq. (5-6) while the CAPWAP estimates at EOD were used for the data
points from field tests. The measured pile setup resistance (Rm-setup) was determined to be the
difference between the SLT measured pile resistance at any time (Rm-t) and the initial pile
resistance at EOD (Rm-EOD). Figure 5.19 shows the different theoretical normal distribution
curves, representing different COV values of 0.181 and 0.330 for EOD and setup respectively,
and highlights the different uncertainties associated with initial pile resistance at EOD and setup
resistance. The large difference in COV values confirms the disparity in the associated
uncertainties and promotes the development of resistance factors separately for EOD condition
and effects of setup.
Considering the AASHTO (2007) strength I load combination for axially loaded piles, the
equation of the resistance factor for pile setup (φsetup) was derived as:
[
(
(
)
(
)
(
)
(
]
)
√ [(
)
√
(
)(
(
)
)
91
)]
(5-8)
where
λEOD
λsetup
COVREOD
COVRsetup
φEOD
α
= the resistance bias factor of the resistance ratio estimator for EOD;
= the resistance bias factor of the resistance ratio estimator for setup;
= the coefficient of variation of the resistance ratio estimator for EOD;
= the coefficient of variation of the resistance ratio estimator for setup;
= resistance factor for initial pile resistance at EOD;
= ratio between initial pile resistance and total serviced dead and live
loads, (REOD/(QD+QL));
βT
= target reliability index;
γD, γL
= the dead load factor (1.25) and live load factor (1.75);
λD, λL
= the dead load bias (1.05) and live load bias (1.15);
COVD, COVL = the coefficients of variation of dead load (0.1) and live load (0.2); and
QD/QL
= dead to live load ratio.
Table 5.9. Summary of resistance ratio estimators for EOD and setup
Measured Pile Measured Pile Estimated Pile
Estimated
Project
Resistance at
Setup
Resistance at
Pile Setup
RRE for EOD
RRE for Setup
ID
EOD, Rm-EOD
Resistance,
EOD, Re-EOD
Resistance,
(Rm-EOD/Re-EOD)
(Rm-setup/Re-setup)
(kip)
Rm-setup (kip)
(kip)
Re-setup (kip)
6
77a
47c
71
38
1.09
1.26
12
135a
49c
155
79
0.87
0.62
42
54a
28c
85
45
0.63
0.63
44
89a
42c
94
50
0.95
0.84
51
130a
62c
128
59
1.02
1.05
57
106a
75c
94
55
1.14
1.37
62
67a
24c
76
37
0.88
0.65
63
43a
23c
59
32
0.72
0.72
64
82a
51c
71
34
1.16
1.49
67
92a
48c
121
63
0.76
0.76
102
82a
46c
84
49
0.97
0.92
109
116a
29c
147
76
0.79
0.38
ISU2
81b
44d
77
54
1.05
0.81
ISU3
99b
51d
82
62
1.20
0.83
ISU4
102b
52d
95
64
1.07
0.82
ISU5
178b
65d
143
88
1.24
0.74
ISU6
145b
68d
140
89
1.03
0.77
a
– adjusted from SPT based pile setup equation;
b
– CAPWAP estimates at EOD;
c
– difference between SLT measured pile resistance at time (t) and initial pile resistance at EOD using WEAP; and
d
– difference between SLT measured pile resistance at time (t) and initial pile resistance at EOD using CAPWAP.
The detailed derivation of Eq. (5-8), based on the original FOSM and its assumptions of
lognormal distribution and a mutually independent relationship between load and resistance,
were explicitly described by Ng (2011). Eq. (5-8) reveals that the φsetup value is dependent on
various parameters. The probabilistic characteristics (γ, λ and COV) of the random variables QD
and QL are defined in Eq. (5-8) with the recommended values recapitulated in parentheses
(Nowak 1999). The probabilistic characteristics (λ and COV) of the random variables REOD and
Rsetup were determined in Figure 5.19. The target reliability indices (βT) of 2.33 (corresponding
to 1% probability of failure) and 3.00 (corresponding to 0.1% probability of failure), as
recommended, for representing redundant and non-redundant pile groups respectively
(Paikowsky et al. 2004), were selected for the calculations. Neglecting the effect of pile setup
and assuming the QD/QL ratio of 2.0, the φEOD values were determined to be 0.66 and 0.55 for the
92
βT values of 2.33 and 3.00, respectively, using the original FOSM. Therefore, the φsetup value can
be determined depending on the α value, the only remaining unknown, as plotted in Figure 5.20.
This figure illustrates that with an increase in α values from 0.2 to 1.73 the φsetup values reduce
by a factor of 2.2 and 1.7 for βT values of 2.33 and 3.00, respectively. It also shows that the φsetup
values for βT value of 2.33 are greater than those for βT value of 3.00, except when α values
become greater than 1.73 where the opposite is seen. The continuous increase in α values
correlates with φsetup values that reduce towards zero. This means that pile setup effect could be
ignored in pile design at an extremely high REOD value with respect to total load. Similar
observations are observed for the efficiency factors (φ/λ). It is reasonable for Eq. (5-8) to yield a
smaller φsetup value when the estimated REOD is much higher than the loads, so the computed total
factored pile resistances are not significantly larger than the factored loads, resulting in an over
conservative design. Therefore, an efficient driven pile system shall consider the optimum
contribution from pile setup resistance by having a smaller α value, which may be accomplished
by having a smaller pile group with a shorter individual pile length.
Histogram of RRE for EOD and Setup
Normal Distribution
2.5
Conditions
RRE for EOD
RRE for Setup
Density
2.0
Mean StDev N
0.9754 0.1768 17
0.8624 0.2849 17
COV
EOD = 0.181
Setup = 0.330
1.5
1.0
0.5
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
Ratio Between Measured and Estimated Pile Resistance
Figure 5.19. Different uncertainties involved between EOD and setup
93
0.60
Note: Based on φEOD = 0.66 and 0.55
for βT = 2.33 and 3.00, respectively.
λEOD= 0.975; COVEOD = 0.177
λsetup = 0.862; COVsetup = 0.330
WEAP-IABB (βT = 3.00)
0.80
0.70
0.40
0.60
0.31
0.50
0.30
βT = 2.33
0.24
0.40
0.21
0.20
0.30
0.19
Efficiency Factor, φ/λ
Resistance Factor for Setup, φsetup
0.50
0.90
WEAP-IABB (βT = 2.33)
βT = 3.00
0.20
0.10
0.10
0.00
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1.60
1.80
2.00
0.00
2.20
α = REOD/(QD+QL)
Figure 5.20. Resistance factor for pile setup resistance
To reflect the Iowa DOT’s current practice, α values were computed based on design and driving
information of production piles installed at six ISU’s field test sites as summarized in Table 5.10.
The location of abutments, production pile sizes, soil profiles classified in accordance to the
procedure described in Section 2.1.2, and actual driven pile lengths are summarized. Given the
total serviced load (QD+QL) exerting on each production pile and the measured driving resistance
determined at EOD (REOD) using WEAP, α value (i.e.,
) is calculated for each location
except for those with either no driving information or situated in a mixed soil profile. Figure
5.21 shows the histogram and theoretical normal distribution of the computed α values given in
Table 5.10. Among the five calculated α values, three values fall between 2.0 and 3.0 while the
other two are greater than 3.0. Based on the theoretical normal distribution, the mean and
standard deviation were determined to be 2.74 and 0.41, respectively. If this average α value of
2.74 would have been used to determine φsetup from Figure 5.20, the contribution of pile setup
will be neglected in the proposed LRFD framework (i.e., φsetup is less than zero) . Before making
any recommendations, α values were re-evaluated based on additional and independent data sets
given by Iowa DOT on completed production steel H-piles as summarized in Table 5.11. These
additional data were taken from 17 project sites at 10 different counties in Iowa. The location of
the production piles, pile sizes, description of embedded soils, and plan pile lengths are tabulated
accordingly. A total of 604 piles was selected for a similar analysis, and the histogram and
theoretical normal distribution of α values are shown in Figure 5.22. The normal distribution
shows that the mean and standard deviation are 2.78 and 0.95, respectively. This mean value of
94
2.78 is comparable to the mean value of 2.74 determined in Figure 5.21, in which the effect of
pile setup would be neglected. Furthermore, most of the α values shown in both Figure 5.21 and
Figure 5.22 are higher than the target value of 2.0, which is determined based on current Iowa
LRFD design practice as illustrated
(5-9)
where
R
QT
φ
= the nominal pile resistance estimated using Iowa Blue Book;
= total service load or dead plus live loads;
= resistance factor of 0.725 currently used in a pile design using Iowa Blue
Book method; and
= equivalent load factor of 1.45 adopted by Iowa DOT.
γ
Table 5.10. Summary of information on production piles at ISU test sites
Production
Piles at
Location of
ISU’s Test Pile
Abutment
Production
Pile Size
Classified
Soil
Profile
South
North
South
North
South
North
West
East
West
East
South
North
HP 10 × 57
HP 10 × 57
HP 10 × 42
HP 10 × 42
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 42
HP 10 × 42
Clay
Clay
Mixed
Mixed
Clay
Clay
Clay
Clay
Clay
Clay
Mixed
Mixed
ISU1
ISU2
ISU3
ISU4
ISU5
ISU6
Actual
Driven
Length
(ft)
48.6
58.3
Serviced
Load Per
Pile, QD+QL
(kip)
86.1
86.1
Measured
Nominal Driving
Resistance at
EOD, REOD (kip)
269.6
260.8
Calculated
α Value
3.13
3.03
No driving information
78.8
79.3
72.4
92
268
92
232
No driving information
94
200
2.91
2.52
2.13
No driving information
49.1
46.9
62.3
62.3
176
116
-
Histogram of Alpha Value (Production Piles at ISU Field Test Sites)
Normal
Mean
StDev
N
40
2.744
0.4140
5
Percent
30
20
10
0
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
Alpha Value (REOD/Q)
3.0
3.2
3.4
3.6
Figure 5.21. Histogram and theoretical normal distribution of α values based on
information of production piles at ISU field test sites
95
Table 5.11. Summary of additional data on production piles in Iowa
Iowa CountyID Number
Lee-135
Buena Vista-53
Jasper-44
Dickinson-35
Plymouth-40
Wright-63
Carroll-122
Cedar-82
Tama-114
Tama-119
Lee-130
Lee-147
Lee-148
Lee-157
Lee-138
Pier 2
North Abutment
West Abutment
East Abutment
Pier 1 West
Pier 2 East
West Abutment
Pier 2
East Abutment
East Abutment
West Abutment
East Pier
West Abutment
East Pier
East Abutment
West Abutment
South Abutment
North Abutment
South Abutment
North Abutment
Pier 1
Pier 3
Pier 2
Pier
North Abutment
South Abutment
Pier
North Abutment
South Abutment
Pier
SBL S. Abutment
NBL N. Abutment
SBL Pier 1
NBL S. Abutment
NBL Pier 1
South Abutment
Pier
East Abutment
West Abutment
West Abutment
East Abutment
Pier 1
Production
Pile Size
HP 10 × 57
HP 10 × 57
HP 10 × 42
HP 10 × 42
HP 12 × 53
HP 12 × 53
HP 10 × 57
HP 12 × 53
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 12 × 53
HP 10 × 57
HP 10 × 57
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 10 × 42
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 10 × 57
HP 12 × 53
West Pier
HP 10 × 57
West Abutment
HP 10 × 57
Pier 1
HP 10 × 57
Pier/Abutment
Buena Vista-57
Johnson-285
Soil Description
Sandy Glacial Clay
Firm Sandy Glacial Clay
over Very Firm Glacial
Clay
Silty Clay
Stiff Silty Clay to Very
Firm Glacial Clay
Sandy Lean Clay
Firm Sandy Lean Clay
Very Firm Glacial Clay
Silty Clay - Glacial Clay
Very Firm Glacial Clay
Glacial Clay
Silty Clay to Firm
Glacial Clay
Silty Clay to Firm
Glacial Clay
Silty Clay to Firm
Glacial Clay
Very Firm Glacial Clay
Silty Clay to Very Firm
Glacial Clay
Firm Sandy Glacial Clay
Stiff Silty Clay to Very
Firm Glacial Clay
Firm Glacial Clay
Stiff Silty Clay
Firm Glacial Clay
Silty Clay
Very Firm Glacial Clay
Stiff Silty Clay to Firm
Glacial Clay
Silty Clay to Glacial
Clay
Glacial Clay to Gravelly
Sand
Soft Silty Clay to Very
Firm Glacial Clay
Sandy Lean Clay
96
Total Number
of Piles
29
12
7
7
13
13
7
14
7
6
6
8
6
12
5
5
7
7
5
5
22
22
22
27
12
13
27
14
13
36
8
8
24
8
24
12
26
11
11
7
7
27
Plan Pile
Length (ft)
45
60
60
60
60
60
70 & 80
70
75 & 80
60
60
60
80
70
45
45
55
55
80
80
55
55
60
44.28
63.96
70
45
60
60
50
80
80
55
75
55
60
40
70
70
70
70
45
12
65
6
70
24
55
Histogram of Alpha Value
Normal
16
Mean
StDev
N
14
2.776
0.9528
604
12
Percent
10
8
6
4
2
0
1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0 5.2
Alpha Value (REOD/Q)
Figure 5.22. Histogram and theoretical normal distribution of α values based on additional
data of production piles in Iowa
This comparison shows that most of the production piles were installed with higher capacities
than that required using Eq. (5-9). In other words, the production piles were conservatively
installed. In contrast, to eliminate an additional safety margin incurred to REOD, which has been
accounted for using φEOD in Eq. (5-8), a lowest α value of 1.0 can be assumed. Referring to
Figure 5.20 based on α value of 1.0, φsetup values of 0.31 and 0.24 can be determined for the βT
values of 2.33 and 3.00, respectively. However, these φsetup values could be high based upon the
actual results revealed in Figure 5.21 and Figure 5.22 with an average α value of about 2.7 as
well as the target α value of 2.0. To compromise between the conservatism observed in the
actual production pile constructions and the idealistic condition that eliminates the additional
safety margin to the REOD, α value of 1.8 can be selected between the lowest value of 1.0 and the
average value of 2.7. Alternatively, α value of 1.5 can be selected between the lowest value of
1.0 and the target value of 2.0. If α value of 1.6 is chosen between 1.5 and 1.8 for pile designs in
Iowa, φsetup values of 0.21 and 0.19 can be reasonably recommended for the βT values of 2.33
and 3.00, respectively. In this recommendation, only about 20% of the pile setup resistance
estimated using the proposed methods described in Section 5.6.2 will be considered in the LRFD
of steel H-pile foundations.
97
CHAPTER 6: SUMMARY
Because of the mandate imposed by the Federal Highway Administration (FHWA) on the
implementation of Load Resistance Factor Design (LRFD) in all new bridge projects initiated
after October 1, 2007, the Iowa Highway Research Board (IHRB) sponsored the research project
TR-573 to develop the LRFD commendations for the State of Iowa based on the Pile Load Test
(PILOT) database. PILOT contains pile information about past projects completed by the Iowa
Department of Transportation (Iowa DOT) from 1966 until the late 1980s. To populate PILOT,
especially for dynamic analysis, two add-on research projects (TR-583 and TR-584) were
included to conduct ten (10) full-scale field tests in Iowa to increase the data points for LRFD
resistance factors calculation, develop LRFD recommendations for dynamic methods, and
validate the results of LRFD calibration.
The most common steel H-piles were used in the ten field sites which were selected from Iowa
DOT bridge projects. Chapter 2 describes the six criteria established for selecting the ten field
testing locations. Appendix A shows the layout of the test pile locations. When the test sites
were selected, detailed soil in-situ investigations and laboratory tests were performed to
characterize the soils surrounding the test piles. Standard Penetration Tests (SPT), Cone
Penetration Tests (CPT), Borehole Shear Tests (BST), and modified Borehole Shear Tests
(mBST) were the four selected in-situ soil investigations. In addition, push-in pressure cells
(PCs) were installed near test piles ISU5, ISU6, ISU7, ISU8, and ISU10 to measure total lateral
earth pressure and pore water pressure during driving, re-strikes, and static load tests. Soil
samples collected from SPT boreholes were used for laboratory testing which consisted of basic
soil characterization (i.e., gradation, Atterberg’s limits and moisture content) and consolidation
tests. The detailed descriptions of both in-situ and laboratory soil tests are presented in Chapter
3 and the results of the soil tests are included in the Appendix B.
Besides characterizing the surrounding soils, the properties of the ASTM A572 Grade 50 steel
H-piles and the hammer driving systems are described and presented in Chapter 4. The test piles
were instrumented with strain gauges along their embedded lengths before being driven into the
ground. The details of the strain gauge instrumentations are described in Chapter 4 and their
arrangements are included in Appendix C. The test piles were also instrumented with a pair of
transducers and accelerometers near the pile head for Pile Driving Analyzer (PDA) tests.
The PDA tests were conducted during pile driving, at the end of driving (EOD), and at several
re-strikes. The test piles were re-struck at several durations after EOD and before static load
tests. The PDA force and velocity records at each event (given in Appendix C) were used in the
CAse Pile Wave Analysis Program (CAPWAP) method for a more accurate pile resistance
estimation, which was achieved by performing signal matching.
Hammer blow counts were recorded at EOD and re-strikes and were used in the Wave Equation
Analysis Program (WEAP) bearing graph analysis to determine the pile resistance. Five soil
profile input procedures were used in WEAP analysis: 1) GRLWEAP soil type based method
(ST); 2) GRLWEAP SPT N-value based method (SA); 3) the Federal Highway Administration
(FHWA) DRIVEN program; 4) Iowa Blue Book (Iowa DOT steel pile Design Chart); and 5)
Iowa DOT current approach. The estimated pile capacities and their respective dynamic soil
properties for PDA, CAPWAP, and WEAP are tabulated in Chapter 4.
98
After completing all re-strikes, vertical static load tests were performed on the test piles in
according with ASTM D1143 Procedure A: Quick test method. The pile resistance was
determined from the load-displacement graph based on the Davisson’s criteria. Also, force
distributions were calculated from the strain measurements at each load increment. The
procedure of performing the static load tests is described in Chapter 4 and the results are given in
Appendix C.
99
CHAPTER 7: CONCLUSIONS
The extensive experimental research studies generated important data for concurrent analytical
and computational investigations. Results from re-strikes and static load tests were compared.
The SLT measured load-displacements were compared with the simulated results obtained using
TZ-mBST model. The relationship between PC measurements and estimated pile responses was
assessed. The variation in pile responses was evaluated with respect to the time elapsed after
pile installation and was correlated with the surrounding soil properties. Two analytical pile
setup quantification methods were developed and validated. A new calibration procedure was
developed to incorporate pile setup into LRFD. The results of this research project led to the
following conclusions:
1. Total pile resistance is contributed predominantly from shaft resistance while end bearing
ranges between 2% to 28% of the total resistance.
2. Shaft resistance is higher at a stiffer soil layer, represented with a relatively large
uncorrected SPT N-value.
3. The TZ-mBST model has proven to provide a better match of the measured SLT loaddisplacement relationship when compared with TZ-CPT model.
4. The continuous logarithmic dissipation of pore water pressure with time explains the
observed pile setup trend. Alternatively for the cohesionless soil layer, the immediate
and complete pore water dissipation before EOD explains the minimal variation in pile
resistance over time.
5. Comparison of the measured pile driving resistances concludes that pile setup occurs in
piles embedded in clay and mixed soil profiles but not in sand profile. The re-strike and
load test measurements show that the increase in total pile resistance has a general
logarithmic trend with respect to time for clay and mixed soil profiles. Furthermore, the
field test results indicate that pile resistance increases immediately and significantly after
pile installation, and thus, the performance of re-strikes within a day after EOD is
reasonably recommended. The CAPWAP results in clay profile reveal that both shaft
resistance and end bearing increase logarithmically with time, and pile setup is
contributed predominantly from the shaft resistance and minimally from the end bearing.
Unlike the clay profile, test pile ISU8 in the mixed soil profile experienced a contrasting
observation.
6. The experimental results confirmed that the amount of increase in shaft resistance at a
given time was dependent on the combined effects of the: (1) soil permeability, which
was measured directly using the coefficient of consolidation or indirectly using the SPT
N-values; (2) soil compressibility, which was measured using the plasticity index (PI)
values; and (3) corresponding thicknesses of all the cohesive layers along the embedded
pile length. The quantitative correlation studies specifically revealed that the increases in
total pile capacity and shaft resistance of a pile embedded in a cohesive clay soil were
directly proportional to Cv or Ch and were inversely proportional to SPT N-values and PI
values larger than 12%. However, they were directly proportional to PI values smaller
100
than 12% for a pile embedded in a sandy cohesive soil. Alternatively, the increase in the
end bearing component showed no significant correlations to either SPT N-values or Ch
values, but was directly proportional to the Cv and inversely proportional to the PI values.
7. Based on the field test results and the successful correlation studies, two analytical
quantification methods were established to estimate the pile setup rate (C) in a clay
profile using the influential soil properties measured from the commonly used SPT &
CPT and using the dynamic analysis methods (WEAP and CAPWAP). The first method,
given by Eq. (5-4), involves both SPT and CPT while the second method, given by Eq.
(5-5), involves only SPT. The quantification of pile setup rate in terms of soil properties
avoids the inconvenient re-strikes and allows the estimation of pile resistance at any time
(t) using Eq. (5-3).
8. Using twelve data records from PILOT along with the five field tests, the confidence of
the proposed pile setup methods were validated, as illustrated in Figure 5.17 and
summarized in Table 5.8, at various confidence levels. The maximum error falls between
-17.2% and 1.9%, based on the SPT based setup method when used in conjunction with
WEAP at the 98% confidence interval. Generally, the range of the errors is smaller for
pile setup methods when used in conjunction with CAPWAP than those with WEAP.
9. Recognizing the difference in uncertainties associated with the estimations of initial pile
resistance at EOD and pile setup resistance, representing different COV values of 0.181
and 0.330 for WEAP, separate resistance factors are calculated for both initial pile
resistance and setup resistance to ensure the reliability theory based LRFD framework is
adequately followed. Considering the AASHTO (2007) strength I load combination for
axially loaded piles, the resistance factor for pile setup (φsetup) is calculated using Eq.
(5-8), derived based on FOSM and explicitly described by Ng (2011). For a typical α
value of 1.6, QD/QL ratio of 2.0, and φEOD of 0.66 for the βT=2.33, the φsetup value of 0.21
can be conservatively recommended.
101
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and Foundation Division, ASCE, paper No. 3306, Vol. 127, Part 1, 1145-1193.
Suleiman, M. T., Stevens, L., Jahren, C. T., Ceylan, H., and Conway, W. M. (2010).
Identification of Practices, Design, Construction, and Repair Using Trenchless
Technology. Final Research Report. Iowa Department of Transportation Project Number
IHRB-06-09, Ames, Iowa: Institute for Transportation, Iowa State University.
Sully, J., & Campanella, R. (1994). Evaluation of Field CPTU Dissipation Data in
Overconsolidated Fine-Grained Soils. XIII ICSMFE (p. 4). New Delhi, India: XIII
CIMSTF.
Thurman, A. (1964). Computed Load Capacity and Movement of Friction and End-Bearing Piles
Embedded in Uniform and Stratified Soil. Ph.D. Thesis. Carnegie Institute of
Technology.
Tomlinson, M. (1971). Some Effects of Pile Driving on Skin Friction. Proceedings Conference
on Behavior of Piles (pp. 107-114). London: ICE.
Vande Voort, T., Suleiman, M., & Sritharan, S. (2008). Design and Performance Verification of
UHPC Piles for Deep Foundations (Final Report). IHRB Project No. TR-558. Ames
Iowa: Institute for Transportation, Iowa State University.
Wroth, C., & Wood, D. W. (1978). The Correlation of Index Properties with Some Basic
Engineering Properties of Soils. Canadian Geotechnical Journal, 15(2), 137-145.
Zheng, J. J., Lu, Y. E., Yin, J. H., & Guo, J. (2010). Radial Consolidation with Variable
Compressibility and Permeability Following Pile Installation. Computers and
Geotechnics, 37(3), 408-412.
105
APPENDIX A: LOCATIONS OF TEST PILES AND IN SITU SOIL TESTS
- Cone Penetration Test (CPT)
Figure A.1. Test Pile ISU1 at Mahaska County
107
980.2
Test Pile
SPT/BST
LOCATION
IA 978 OVER BNSF RR
T-72N R-943 W
SECTION 23/22
GLENWOODTOWNSHIP
MILLS COUNTY
BRIDGE MAINT. NO. 6502.4S978
CPT
- Cone Penetration Test (CPT)
- Standard Penetration Test (SPT)
and Borehole Shear Test (BST)
Figure A.2. Test Pile ISU2 at Mills County
- Cone Penetration Test (CPT)
- Standard Penetration Test (SPT)
and Borehole Shear Test (BST)
SPT/BST
LOCATION
10 ft Test Pile
4 ft
I-35/80/235 INTERCHANGE
NORTH EAST OF DES MOINES
S-W CONNECTOR I-235 TO I-80
RAMP OVER I-80
T-19 N R-23W
DELAWARE TOWNSHIP
POLK COUNTY
CPT
Figure A.3. Test Pile ISU3 at Polk County
108
Test Pile
≈50 ft
CPT
SPT/BST/
mBST
- Cone Penetration Test (CPT)
- Standard Penetration Test (SPT)
Borehole Shear Test (BST) and
modified Borehole Shear Test
(mBST)
Figure A.4. Test Pile ISU4 at Jasper County
PC1
18 in.
PC2
8 in.
LOCATION
SPT/BST/
CPT 1 & 2 12ft mBST
7ft
Test Pile
U.S.34 OVER I-35
T-72N R-26 W
SECTION 24
WARD TOWNSHIP
CLARKE COUNTY
BRIDGE MAINT. NO. 2015.2R&L034
- Push-In Pressure Cells (PC)
- Cone Penetration Test (CPT)
- Standard Penetration Test (SPT)
Borehole Shear Test (BST) and
modified Borehole Shear Test
(mBST)
50 ft
CPT 3
Figure A.5. Test Pile ISU5 at Clark County
109
LOCATION
10 ft
16 ft
4 ft 7 in.
IA 150 OVER BEAR CREEK
T-88 N R-9 W
SECTION 27
SUMNER TOWNSHIP
BUCHANAN COUNTY
BRIDGE MAINT. NO. 1036.8S150
5 ft
Test Pile Test Pile
ISU 6 ISU 7 SPT/BST/
mBST
CPT
14 in. PC1
PC4
PC3
24 in.
9 in.
- Push-In Pressure Cells (PC)
- Cone Penetration Test (CPT)
- Standard Penetration Test (SPT)
Borehole Shear Test (BST) and
modified Borehole Shear Test
(mBST)
Figure A.6. Test Piles ISU6 and ISU7 at Buchanan County
Test Pile
CPT
2 ft
5.5 ft
14.5 ft
SPT/BST/
mBST
PC4
15.5 in.
- Push-In Pressure Cells (PC)
- Cone Penetration Test (CPT)
- Standard Penetration Test (SPT)
Borehole Shear Test (BST) and
modified Borehole Shear Test
(mBST)
Figure A.7. Test Pile ISU8 at Poweshiek County
110
LOCATION
U.S.6 OVER BEAR CREEK
T-80N R-14 W
SECTION 10
BEAR CREEK TOWNSHIP
POWESHIEK COUNTY
BRIDGE MAINT. NO. 7999.8S006
CREEK
Meekers Landing Rd
9ft
6ft
6ft CPT SPT
LOCATION
CO Rd H40 OVER CREEK
SECTION 4
JACKSON TOWNSHIP
DES MOINES COUNTY
Test Pile
- Cone Penetration Test (CPT)
- Standard Penetration Test (SPT)
Figure A.8. Test Pile ISU9 at Des Moines County
PC4
10 in.
9ft
6ft
7ft
Cedar River
CPT SPT
Test Pile
I-80 West
I-80 East
- Push-In Pressure Cells (PC)
- Cone Penetration Test (CPT)
- Standard Penetration Test (SPT)
LOCATION
I-80 OVER CEDAR RIVER
BETWEEN EXIT 265 AND 267
ROCHESTER TOWNSHIP
CEDAR COUNTY
Figure A.9. Test Pile ISU10 at Cedar County
111
APPENDIX B: RESULTS OF IN SITU SOIL INVESTIGATIONS AND SOIL
PROFILES
112
B.1. Diagrammatic soil profile
CPT 2 Measurements
0
0
Tip Resistance
qc (Ton/ft2)
CPT 1 Measurements
Soil Behavior
Soil Behavior
Sleeve Friction Pore Pressure Type Zone Tip Resistance
Sleeve Friction Pore Pressure Type Zone CPT Soil
u2 (psi)
fs (Ton/ft2)
UBC (1983)
UBC (1983) Description
fs (Ton/ft2)
u (psi)
qc (Ton/ft2)
700 0
800 0
10
12 0
40 0
8 -6 2
-100
12
10 0
clay
5
sensitive
fine
grained
BST
Disturbed
Sample
(USCS)
φ = 13.48º
c = 1.16 psi
DS-1( ML)
φ = 41.18º
c = 0 psi
DS-2( CL)
10
clay
15
silty sand
to sand
Depth (ft)
20
φ = 4.26º
c =3.56 psi
sandy silt
to clayey silt
25
sand to
silty sand
clayey silt
to silty clay
V. Stiff
Fine
Grained
Clay
30
35
40
Ma
45
50
Figure B.1.1. In-situ soil investigations and soil profile for ISU1 at Mahaska County
113
DS-3(CL )
DS-4(CL )
DS-5( CL)
CPT Measurements
0
Tip Resistance
qc (Ton/ft2)
Sleeve Friction
fs (Ton/ft2)
90
0
2
Pore Pressure
u2 (psi)
-20
Soil Behavior
Type Zone
UBC (1983)
100
0
12
CPT Soil
SPT N-value
Description (Corrected N-value)
BST
0
3(5)
clay
Stiff silty clay
w/ trace sand seams
Disturbed
Sample
(USCS)
φ = 6.85º
c = 2.97 psi
DS-1(SC)
φ = 40º
c = 0 psi
DS-2(CL)
3(5)
10
3(5)
3(5)
clayey silt
to silty clay
20
14(15)
Stiff silty clay
w/ trace sand seams
silty clay
to clay
30
3(3)
DS-3(CL)
Depth (ft)
Stiff silty clay
w/ trace sand seams
40
clay
50
clayey silt to
silty clay
4(3)
Stiff silty clay
w/ trace sand seams
4(3)
DS-4(CL)
Stiff to firm
Sandy silt
DS-5(CL)
60
DS-6(CL)
Stiff to firm
Sandy silt
70
12(8)
80
Pore pressure
dissipation test
Figure B.1.2. In-situ soil investigations and soil profile for ISU2 at Mills County
114
CPT Measurements
0
Tip Resistance
qc (Ton/ft2)
Sleeve Friction
fs (Ton/ft2)
160 0
5
Pore Pressure
u2 (psi)
-20
100
Soil Behavior
Type Zone
UBC (1983)
0
CPT Soil
Description
12
SPT N-value
(Corrected N-value)
BST
Disturbed
Sample
(USCS)
0
clay
φ = 0º
c = 7.45 psi
dark brown clay
DS-1(CL)
8(11)
clayey sand
coarse sand
10
11(12)
DS-2(SM)
clayey silt to
silty clay
20
grey silty clay
5(5)
φ = 11.94º
c = 2.45 psi
grey silt
7(6)
DS-3
(SM-SC)
Depth (ft)
30
12(10)
sandy silt to
clayey silt
40
clayey silt
to silty clay
DS-4(CL)
9(7)
grey clay
10(7)
clay
50
DS-5(CL)
grey brown
10(7) silty clay
clayey silt to
silty clay
60
5(3)
light brown
silty clay
DS-6(CL)
DS-7(SM)
21(12)
v. stiff fine
grained
70
Pore pressure
dissipation test
Figure B.1.3. In-situ soil investigations and soil profile for ISU3 at Polk County
115
CPT Measurements
0
0
Tip Resistance
qc (Ton/ft2)
Sleeve Friction
fs (Ton/ft2)
120
0
3
Pore Pressure
u2 (psi)
-20
120
0
Soil Behavior
Type Zone
UBC (1983)
12
CPT Soil
Description
SPT N-value
(Corrected N-value)
BST
(mBST)
Disturbed
Sample
(USCS)
black clay
silty clay
to clay
silty sand
to sandy silt
sensitive
fine grained
10
sandy silt
to clayey silt
silty sand
to sandy silt
Depth (ft)
20
DS-1(CL)
3(6)
4(6)
sand w/ silt
DS-3(SM)
coarse sand
DS-4(SW)
6(6) w/ gravel
grey glacial
11(10) clay
clay
30
DS-2
(SW-SC)
fine mud w/ little sand
φ = 8.53º
c = 2.61 psi
(α = 19.29º)
(a = 0.48psi)
DS-6(CL)
14(11)
silty clay
to clay
40
10(8) grey glacial
DS-7(CL)
clay
φ = 21.80º
c = 4.11 psi
(α = 15.11º)
(a = 4.11 psi)
clayey silt
to silty clay
12(8)
50
DS-5(CL)
DS-8(CL)
13(9)
DS-9(CL)
DS-10(CL)
60
Pore pressure
dissipation test
Figure B.1.4. In-situ soil investigations and soil profile for ISU4 at Jasper County
116
CPT 1 Measurements
0
0
Tip Resistance
qc (Ton/ft2)
80
Sleeve Friction
fs (Ton/ft2)
0
3
Pore Pressure
u2 (psi)
-12
8
CPT 2 Measurements
Soil Behavior
Type Zone
UBC (1983)
0
12
0
Tip Resistance
qc (Ton/ft2)
80
Sleeve Friction Pore Pressure
fs (Ton/ft2)
u2 (psi)
0
3
-12
5
10
20
Depth (ft)
Depth (ft)
15
25
30
35
40
45
Figure B.1.5. Cone Penetration Tests and soil profile for ISU5 at Clarke County
117
8
Soil Behavior
Type Zone
UBC (1983)
0
12
CPT 3 Measurements
0
0
Tip Resistance
qc (Ton/ft2)
80
Sleeve Friction
fs (Ton/ft2)
0
3
Pore Pressure
u2 (psi)
-12
8
CPT Soil
Description
Soil Behavior
Type Zone
0
12
SPT N-value
(Corrected N-value)
BST
(mBST)
Disturbed
Sample
(USCS)
grey silty clay
DS-1(SC)
6(12)
5
light brown
silty clay
10
φ = 25.05º
c = 2.17 psi
(α = 22.71º)
(a = 2.19 psi)
clay
DS-2(ML)
DS-3(CL)
8(8)
15
grey clay w/
trace sand
PC1 at
23.17 ft
DS-4(CL)
Depth (ft)
9(8)
φ = 5.43º
c = 3.79 psi
(α = 7.41º)
(a = 2.63 psi)
20
25
PC2 at
23.25 ft
silty clay
to clay
10(7)
30
clay
35
brown grey
silty clay
Based on SPT Borehole
DS-5(CL)
φ = 27.04º
c =10.53 psi
(α = 14.98º)
(a = 6.12 psi)
Clayey sand
22(14) sandy clay
40
silty clay
to clay
20(12)
DS-6(CL)
DS-7(SC)
greybrown
silty clay
DS-8(CL)
15(9)
45
Pore pressure
dissipation test
Figure B.1.6. In-situ soil investigations and soil profile for ISU5 at Clarke County
118
Push-in Pressure Cells
CPT Measurements
Tip Resistance
qc (Ton/ft2)
0
0
140
Sleeve Friction
fs (Ton/ft2)
0
5
Pore Pressure
u2 (psi)
-10
Soil Behavior
Type Zone
UBC (1983)
70
0
12
CPT Soil
Description
SPT N-value
(Corrected N-value)
sandy gravel
dark sandy clay
clay
12(19)
10
sand to
silty sand
20
clay
PC1 at
28 ft (ISU7)
Depth (ft)
sandy silt
8(11)
φ = 31.59º
c = 0.073 psi
(α = 22.29º)
(a = 0 psi)
φ = 25.87º
c = 1.69 psi
(α = 6.28º)
(a = 2.74 psi)
silty sand
to sandy silt
silty clay
to clay
PC3 at
34 ft (ISU6)
PC4 at
34 ft (ISU6)
DS-2(SM)
DS-4(CL)
10(8) sandy clay
DS-5(CL)
16(12)
DS-6(CL)
23(15)
50
silty clay
clayey silt
to silty clay
DS-1(SC)
8(8)
23(16)
clayey silt
to silty clay
Disturbed
Sample
(USCS)
DS-3(CL)
fine sand
30
40
sandy silt
medium sand
23(25) w/ gravel
BST
(mBST)
22(15)
φ = 30.28º
c = 0.02 psi
(α = 25º)
(a = 2.01 psi)
DS-7(ML)
medium sand
60
silt w/ sand
DS-8(CL)
70
Pore pressure
dissipation test
Push-in Pressure Cells
Figure B.1.7. In-situ soil investigations and soil profile for ISU6 and ISU7 at Buchanan County
119
CPT Measurements
0
Tip Resistance
qc (Ton/ft2)
350
Sleeve Friction
fs (Ton/ft2)
0
5
Pore Pressure
u2 (psi)
-20
100
Soil Behavior
Type Zone
UBC (1983)
0
CPT Soil
Description
SPT N-value
(Corrected N-value)
BST
(mBST)
12
Disturbed
Sample
(USCS)
0
5(11)
clay
6(9)
10
4(5)
DS-1(CL)
φ = 33.02º
c = 1.02 psi
(α = 27.38º)
(a = 0.22 psi)
DS-2(CL)
dark grey
silty clay
DS-3(CL)
20
PC4 at
14 ft
silty clay
to clay
silty sand to
sandy silt
Depth (ft)
30
sand
clayey silt
to silty clay
40
silty sand
to sandy silt
50
clayey silt
to silty clay
silty clay
to clay
60
5(5) light grey clay
2(2)
fine sand
fine to coarse
2(2) sand
DS-4(CL)
φ = 14.04º
c = 1.93 psi
(α = 0º)
(a = 3.91 psi)
DS-5(CL)
DS-6(SW)
2(2)
11(8) grey clay
φ = 17.97º
c = 2.80 psi
(α = 1.07º)
(a = 7.62 psi)
10(7)
24(16)
DS-7(CL)
DS-8(CL)
grey clay
21(13)
DS-9(CL)
19(12)
DS-10(CL)
70
Pore pressure
dissipation test
Push-in Pressure Cells
Figure B.1.8. In-situ soil investigations and soil profile for ISU8 at Poweshiek County
120
CPT Measurements
0
0
Tip Resistance
qc (Ton/ft2)
700
Sleeve Friction
fs (Ton/ft2)
0
8
Pore Pressure
u2 (psi)
0
400
Soil Behavior
Type Zone
0
12
CPT Soil
Description
SPT N-value
(Corrected N-value)
sandy silty to
clayey silt
5
clay
10
15
silty clay
Disturbed
Sample
(USCS)
8(16)
DS-1
(SM;SC)
4(5)
DS-2(CL)
5(5)
DS-3
(SM; SC)
Fine grey sand
w/ clay
6(6)
course sand
DS-4(SW)
Depth (ft)
20
sand
25
7(6)
11(9)
30
14(11)
35
Sand w/ gravel
grey sand
13(10)
40
DS-5(SW)
DS-6(SP)
15(11)
45
32(22)
50
grey sand
w/ gravel
DS-7(SW)
Pore pressure
dissipation test
Figure B.1.9. In-situ soil investigations and soil profile for ISU9 at Des Moines County
121
CPT Measurements
Tip Resistance
qc (Ton/ft2)
00
00
Sleeve Friction
2
0 fs (Ton/ft ) 22
250 0
250
Pore Pressure Soil Behavior
u2 (psi) 10
00 Type Zone 12
12
00
10
CPT Soil
Description
SPT N-value
(Corrected N-value)
sandy silty to
clayey silt
55
10
10
Disturbed
Sample
(USCS)
DS-1 (SW)
sand to silty sand
21(42)
sandy silt
to clayey silt
6(9)
Medium sand
DS-2
(SP-SM;
SP-SC)
medium course sand
1515
PC4
at 10 ft
28(30)
20
20
Depth (ft)
DS-3 (SW)
14(17)
sand
course sand
w/ gravel
DS-4(SP)
36(35)
25
25
DS-5(SW)
30
30
69(57)
35
35
40
40
34(26)
DS-6
(SW-SM;
SW-SC)
53(37)
DS-7(SW)
45
45
50
50
55
55
52(33)
60
60
Push-in Pressure Cells
Figure B.1.10. In-situ soil investigations and soil profile for ISU10 at Cedar County
122
B.2. Estimated Soil Profiles and Properties Based on Cone Penetration Tests (CPT)
Table B.2.1. Summary of soil properties for ISU1 based on CPT
Soil Types
Average
Effective
Friction Angle,
φ′ (degree)
Average
Undrained Shear
Strength, Su (psi)
Overconsolidation
Ratio (OCR)
0 to 4.43
Clay
31.93
5.63
-
Layer 2
4.43 to
9.19
Sensitive Fine
Grained
30.09
7.19
7.99
Layer 3
9.19 to
15.42
Clay
33.23
19.39
12.74
Layer 4
15.42 to
18.86
Silty Sand to
Sand
41.38
-
-
Layer 5
18.86 to
24.28
Sandy Silt to
Clayey Silt
35.22
39.40
13.32
Layer 6
24.28 to
30.35
Sand to Silty
Sand
42.18
-
-
Layer 7
30.35 to
32.97
Clayey Silt to
silty Clay
37.12
66.20
17.06
Layer 8
32.97 to
33.79
Very Stiff Fine
Grained Sand
36.77
-
-
Layer 9
33.79 to
35.43
Clay
37.74
110.07
26.24
Soil
Profiles
Depth (ft)
Layer 1
Table B.2.2. Summary of soil properties for ISU2 based on CPT
Soil Types
Average
Effective
Friction Angle,
φ′ (degree)
Average
Undrained Shear
Strength, Su (psi)
Average Overconsolidation
Ratio (OCR)
0 to 16
Clay
31.71
14.42
-
Layer 2
16 to 20
Clayey Silt to
Silty Clay
28.51
11.31
7.52
Layer 3
20 to 36
Silty Clay to
Clay
27.07
7.62
2.09
Layer 4
36 to 44
Clay
28.68
11.35
1.84
Layer 5
44 to 73
Clayey Silt to
Silty Clay
27.04
18.10
6.50
Soil
Profiles
Depth (ft)
Layer 1
123
Table B.2.3. Summary of soil properties for ISU3 based on CPT
Soil
Profiles
Depth (ft)
Soil Types
Average Effective
Friction Angle, φ′
(degree)
Average
Undrained Shear
Strength, Su (psi)
Average Overconsolidation
Ratio (OCR)
Layer 1
0 to 7.71
Clay
35.42
25.27
-
Layer 2
7.71 to 34
Clayey Silt to
Silty Clay
32.76
16.55
5.94
Layer 3
34 to 41.5
Sandy Silt to
Clayey Silt
34.36
14.95
3.19
Layer 4
41.5 to
45.11
Clayey Silt to
Silty Clay
31.09
12.13
2.33
Layer 5
45.11 to
55.28
Clay
31.50
22.03
3.72
Layer 6
55.28 to
66.77
Clayey Silt to
Silty Clay
29.09
23.09
2.74
Layer 7
66.77 to
69.88
Very Stiff Fine
Grained
35.60
67.61
7.31
Table B.2.4. Summary of soil properties for ISU4 based on CPT
Soil Types
Average Effective
Friction Angle, φ′
(degree)
Average
Undrained
Shear Strength,
Su (psi)
Average Overconsolidation
Ratio (OCR)
0 to 7.71
Silty Clay to
Clay
34.03
14.69
-
Layer 2
7.71 to
8.86
Silty Sand to
Sandy Silt
34.59
-
-
Layer 3
8.86 to
12.96
Sensitive Fine
Grained
25.41
4.09
2.15
Layer 4
12.96 to
19.85
Sandy Silt to
Clayey Silt
30.68
12.27
5.48
Layer 5
19.85 to
21.16
Silty Sand to
Sandy Silt
35.76
-
-
Layer 6
21.16 to
38.06
Clay
32.76
25.30
6.62
Layer 7
38.06 to
41.17
Silty Clay to
Clay
30.97
18.14
3.76
Layer 8
41.17 to
50.36
Clayey Silt to
Silty Clay
33.29
18.11
3.46
Soil
Profiles
Depth (ft)
Layer 1
124
Table B.2.5. Summary of soil properties for ISU5 based on CPT
Soil Types
Average Effective
Friction Angle, φ′
(degree)
Average
Undrained
Shear Strength,
Su (psi)
Average Overconsolidation
Ratio (OCR)
0 to 25
Clay
31.08
13.28
5.60
Layer 2
25 to 29
Silty Clay to
Clay
29.94
15.71
3.11
Layer 3
29 to 39
Clay
29.72
16.46
2.63
Layer 4
39 to 45
Silty Clay to
Clay
32.09
30.61
3.92
Soil
Profiles
Depth (ft)
Layer 1
Table B.2.6. Summary of soil properties for ISU6 and ISU7 based on CPT
Soil Types
Average Effective
Friction Angle, φ′
(degree)
Average
Undrained
Shear Strength,
Su (psi)
Average Overconsolidation
Ratio (OCR)
0 to 13.12
Clay
33.96
22.27
-
Layer 2
13.12 to
20.01
Sand to Silty
Sand
38.28
-
-
Layer 3
20.01 to
29.36
Clay
28.82
10.27
3.33
Layer 4
29.36 to
30.51
Silty Sand to
Sandy Silt
35.34
-
-
Layer 5
30.51 to
38.22
Silty Clay to
Clay
29.86
14.15
3.05
Layer 6
38.22 to
50.85
Clayey Silt to
Silty Clay
30.56
18.57
2.95
Layer 7
50.85 to
62.50
Clayey Silt to
Silty Clay
33.63
41.68
5.98
Soil
Profiles
Depth (ft)
Layer 1
125
Table B.2.7. Summary of soil properties for ISU8 based on CPT
Soil Types
Average Effective
Friction Angle, φ′
(degree)
Average
Undrained
Shear Strength,
Su (psi)
Average Overconsolidation
Ratio (OCR)
0 to 14.44
Clay
32.50
12.49
-
14.44 to
24.93
24.93 to
32.48
32.48 to
38.06
38.06 to
41.17
41.17 to
49.21
49.21 to
52.66
52.66 to
64.47
Silty Clay to
Clay
Silty Sand to
Sandy Silt
28.15
8.43
2.69
34.62
-
-
41.75
-
-
29.90
16.60
3.18
33.12
-
-
30.41
18.94
3.11
34.27
47.59
6.76
Soil
Profiles
Depth (ft)
Layer 1
Layer 2
Layer 3
Layer 4
Layer 5
Layer 6
Layer 7
Layer 8
Sand
Clayey Silt to
Silty Clay
Silty Sand to
Sandy Silt
Clayey Silt to
Silty Clay
Silty Clay to
Clay
Table B.2.8. Summary of soil properties for ISU9 based on CPT
Soil
Profiles
Depth (ft)
Layer 1
0 to 4.27
Layer 2
Layer 3
4.27 to
15.91
15.91 to
45.93
Soil Types
Average Effective
Friction Angle, φ′
(degree)
Average
Undrained
Shear Strength,
Su (psi)
Average Overconsolidation
Ratio (OCR)
Sandy Silt to
Clayey Silt
46.19
392.44
-
Clay
30.97
71.59
6.90
Sand
40.21
-
-
Table B.2.9. Summary of soil properties for ISU10 based on CPT
Soil
Profiles
Depth (ft)
Layer 1
0 to 4.59
Layer 2
Layer 3
Layer 4
4.59 to
6.56
6.56 to
8.86
8.86 to
22.15
Soil Types
Sandy Silt to
Clayey Silt
Sand to Silty
Sand
Sandy Silt to
Clayey Silt
Sand
Average Effective
Friction Angle, φ′
(degree)
Average
Undrained
Shear Strength,
Su (psi)
Average Overconsolidation
Ratio (OCR)
34.65
108.87
-
41.30
-
-
32.89
115.15
16.66
39.61
-
-
126
B.3. Pore Water Pressure Measurements Using Cone Penetration Tests (CPT)
70
At 57.2 ft
At 35.4 ft
60
Pore Pressure (psi)
50
40
30
20
10
0
0.1
1
10
100
1000
10000
Time (second)
Figure B.3.1. CPT pore water pressure dissipation tests at ISU2 Mills County
70
At 22.15 ft
At 22.15 ft (Extrapolated)
60
At 50.69 ft
Pore Pressure (psi)
50
40
30
20
10
0
0.1
1
10
100
1000
10000
Time (Second)
Figure B.3.2. CPT pore water pressure dissipation tests at ISU3 Polk County
127
90
At 19.5 ft
At 21 ft
At 41 ft
A 41 ft (Extrapolated)
At 50.53 ft
At 50.53 ft (Extrapolated)
80
Pore Pressure ( psi)
70
60
50
40
30
20
10
0
0.1
1
10
100
1000
10000
100000
Time (second)
Figure B.3.3. CPT pore water pressure dissipation tests at ISU4 Jasper County
8
At 38.55 ft
7
Pore Pressure (psi)
6
5
4
3
2
1
0
0.1
1
10
100
1000
10000
Time (second)
Figure B.3.4. CPT pore water pressure dissipation tests at ISU5 Clarke County
128
60
At 17.06 ft
At 22.97 ft
At 30.02 ft
At 50.03 ft
At 50.03 ft (Extrapolated)
Pore Pressure (psi)
50
40
30
20
10
0
0.1
1
10
100
1000
10000
100000
Time (second)
Figure B.3.5. CPT pore water pressure dissipation tests at ISU6 and ISU7 Buchanan
County
140
At 31.84 ft
At 45.11 ft
At 57.25 ft
At 57.25 ft (Extrapolated)
At 64.80 ft
120
Pore Pressure (psi)
100
80
60
40
20
0
-20
0.1
1
10
100
1000
10000
100000
Time (second)
Figure B.3.6. CPT pore water pressure dissipation tests at ISU8 Poweshiek County
129
16
At 30.18 ft
At 45.28 ft
14
Pore Pressure (psi)
12
10
8
6
4
2
0
0.1
1
10
100
1000
10000
Time (Second)
Figure B.3.7. CPT pore water pressure dissipation tests at ISU9 Des Moines County
130
B.4. Borehole Shear Test and modified Borehole Shear Test Results
Shearing Stress,τ (psi)
6
5
τ = 0.24σ + 1.16
φ = 13.48º; c = 1.16 psi (BST)
4
3
2
1
0
0
5
10
Normal Stress,σ (psi)
15
20
Figure B.4.1. ISU1 at 3-ft depth (BST)
9
Shearing Stress,τ (psi)
8
7
6
τ = 0.48σ
φ = 41.18º; c = 0 psi (BST)
5
4
3
2
1
0
0
5
10
Normal Stress,σ (psi)
15
20
Figure B.4.2. ISU1 at 8-ft depth (BST)
Shearing Stress,τ (psi)
6
5
τ = 0.075σ + 3.56
φ = 4.26º; c = 3.56 psi (BST)
4
3
2
1
0
0
5
10
Normal Stress,σ (psi)
15
Figure B.4.3. ISU1 at 16-ft depth (BST)
131
20
Shearing Stress,τ (psi)
6
5
4
τ = 0.12σ + 2.97
φ = 6.85º; c = 2.97 psi (BST)
3
2
1
0
0
5
10
Normal Stress,σ (psi)
15
20
Figure B.4.4. ISU2 at 5-ft depth (BST)
Shearing Stress,τ (psi)
14
12
10
8
τ = 0.84σ
φ = 40º; c = 0 psi (BST)
6
4
2
0
0
5
10
Normal Stress ,σ (psi)
15
Figure B.4.5. ISU2 at 20-ft depth (BST)
10
Shear Stress,τ (psi)
8
τ = 0.0003σ + 7.45
φ = 0º; c = 7.45 psi (BST)
6
4
2
0
0
5
10
15
Normal Stress , σ (psi)
20
Figure B.4.6. ISU3 at 4-ft depth (BST)
132
25
8
7
Shear Stress,τ (psi)
6
5
4
τ = 0.21σ + 2.45
φ = 11.94º; c = 2.45 psi (BST)
3
2
1
0
0
5
10
15
20
25
Normal Stress ,σ (psi)
Figure B.4.7. ISU3 at 23-ft depth (BST)
8
Shear Stress,τ (psi)
7
6
τ = 0.15σ + 2.61
φ = 8.53º; c = 2.61 psi (BST)
5
4
3
2
τ = 0.35σ + 0.48
α = 19.29º; a = 0.48 psi (mBST)
1
0
0
5
10
Normal Stress,σ (psi)
15
20
Figure B.4.8. ISU4 at 27-ft depth (BST & mBST)
12
τ = 0.4σ + 4.11
φ = 21.80º; c = 4.11 psi (BST)
Shear Stress,τ (psi)
10
8
6
τ = 0.27σ + 4.11
α = 15.11º; a = 4.11 psi (mBST)
4
2
0
0
5
10
Normal Stress,σ (psi)
15
Figure B.4.9. ISU4 at 46-ft depth (BST & mBST)
133
20
8
7
Shear Stress (psi)
6
5
4
3
BST ( = 8.70 psi)
BST (σ = 11.60 psi)
BST (σ = 14.50 psi)
BST (σ = 17.40 psi)
mBST (σ = 11.60 psi)
mBST (σ =14.50 psi)
mBST (σ =17.40 psi)
2
1
0
0
50
100
150
200
Shear Displacement (in. x 10-3)
Figure B.4.10. BST and mBST generated shear stress-displacement relationships for ISU4
at 27-ft depth
10
9
8
Shear Stress (psi)
7
6
5
4
BST (σ = 7.25 psi)
BST (σ = 10.15 psi)
BST (σ = 13.05 psi)
mBST (σ = 4.35 psi)
mBST (σ = 7.25 psi)
mBST (σ = 10.15 psi)
mBST (σ = 13.05 psi)
3
2
1
0
0
50
100
150
200
250
Shear Displacement (in. x 10-3)
Figure B.4.11. BST and mBST generated shear stress-displacement relationships for ISU4
at 46-ft depth
134
7
τ = 0.4678σ + 2.1711
φ = 25.08⁰; c = 2.17 psi (BST)
Shaer Shear, τ (psi)
6
5
4
τ = 0.3787σ + 2.4808
α = 20.75⁰; a = 2.48 psi (mBST)
3
2
1
0
0
2
4
6
8
10
Normal Stress, σ (psi)
Figure B.4.12. ISU5 at 8.83-ft depth (BST & mBST)
6
τ = 0.095σ + 3.7918
φ = 5.43⁰; c = 3.79 psi (BST)
Shear Shear, τ (psi)
5
4
τ = 0.13σ + 2.6245
α = 7.41⁰; a = 2.63 psi (mBST)
3
2
1
0
0
5
10
15
20
Normal Stress, σ (psi)
Figure B.4.13. ISU5 at 23.83-ft depth (BST & mBST)
Shear Stress, τ (psi)
25
τ = 0.51σ + 10.527
φ = 27.04⁰; c = 10.53 psi (BST)
20
15
10
τ = 0.2675σ + 6.1154
α = 14.98⁰; a = 6.12 psi (mBST)
5
0
0
5
10
15
20
Normal Stress, σ (psi)
25
Figure B.4.14. ISU5 at 35.83-ft depth (BST & mBST)
135
30
7
6
Shear Stress (psi)
5
4
3
BST (σ = 3.19 psi)
BST (σ = 4.35 psi)
BST (σ = 5.80 psi)
BST (σ = 8.70 psi)
mBST (σ =3.19 psi)
mBST (σ = 4.35 psi)
mBST (σ = 5.80 psi)
mBST (σ = 8.70 psi)
2
1
0
0
50
100
150
200
250
Shear Displacement (in × 10-3)
300
350
Figure B.4.15. BST and mBST generated shear stress-displacement relationships for ISU5
at 8.83-ft depth
6
Shear Stress (psi)
5
4
3
BST (σ = 7.25 psi)
BST (σ = 10.15 psi)
BST (σ = 13.05 psi)
BST (σ = 15.95 psi)
mBST (σ = 7.25 psi)
mBST (σ = 10.15 psi)
mBST (σ = 13.05 psi)
mBST (σ = 15.95 psi)
2
1
0
0
50
100
150
200
250
Shear Displacement (in × 10-3)
300
350
Figure B.4.16. BST and mBST generated shear stress-displacement relationships for ISU5
at 23.83-ft depth
136
25
Shear Stress (psi)
20
15
10
BST (σ = 15.95 psi)
BST (σ = 18.85 psi)
BST (σ = 21.75 psi)
BST (σ = 24.65 psi)
mBST (σ = 15.95 psi)
mBST (σ = 18.85 psi)
mBST (σ = 21.75 psi)
mBST (σ = 24.65 psi)
5
0
0
50
100
150
200
250
Shear Displacement (in × 10-3)
300
350
Figure B.4.17. BST and mBST generated shear stress-displacement relationships for ISU5
at 35.83-ft depth
9
8
τ = 0.62σ + 0.073
φ = 31.59º, c = 0.073 psi (BST)
Shear Stress,τ (psi)
7
6
5
4
3
τ = 0.40σ
α = 22.29º; a = 0 psi (mBST)
2
1
0
0
2
4
6
8
Normal Stress,σ (psi)
10
12
Figure B.4.18. ISU6 and ISU7 at 8.3-ft depth (BST & mBST)
137
14
Shear Stress,τ (psi)
9
8
7
6
5
4
3
2
1
0
τ = 0.49σ + 1.69
φ = 25.87º, c = 1.69 psi (BST)
τ = 0.11σ + 2.74
α = 6.28º; a = 2.74 psi (mBST)
0
5
10
Normal Stress,σ (psi)
15
Figure B.4.19. ISU6 and ISU7 at 11.89-ft depth (BST & mBST)
25
τ = 0.58σ + 0.02
φ = 30.28º, c = 0.02 psi (BST)
Shear Stress,τ (psi)
20
15
τ = 0.47σ + 2.01
α = 25º; a = 2.01 psi (mBST)
10
5
0
0
10
20
Normal Stress,σ (psi)
30
40
Figure B.4.20. ISU6 and ISU7 at 50.3-ft depth (BST & mBST)
8
7
Shear Stress (psi)
6
5
4
BST (σ = 2.90 psi)
BST (σ = 5.80 psi)
BST (σ = 8.70 psi)
BST (σ = 11.60 psi)
mBST (σ = 2.90 psi)
mBST (σ = 5.80 psi)
mBST (σ = 8.70 psi)
mBST (σ = 11.60 psi)
3
2
1
0
0
20
40
60
80
Shear Displacement (in. x 10-3)
100
120
140
Figure B.4.21. BST and mBST generated shear stress-displacement relationships for ISU6
and ISU7 at 8.3-ft depth
138
9
8
Shear Stress (psi)
7
6
5
4
BST (σ = 4.35 psi)
BST (σ = 7.25 psi)
BST (σ = 10.15 psi)
BST (σ = 13.05 psi)
mBST (σ = 4.35 psi)
mBST (σ = 7.25 psi)
mBST (σ = 10.15 psi)
mBST (σ = 13.05 psi)
3
2
1
0
0
50
100
150
Shear Displacement (in. x 10-3)
200
250
Figure B.4.22. BST and mBST generated shear stress-displacement relationships for ISU6
and ISU7 at 11.89-ft depth
25
Shear Stress (psi)
20
15
10
BST (σ = 13.05 psi)
BST (σ = 20.31 psi)
BST (σ = 27.56 psi)
BST (σ = 34.81 psi)
mBST (σ =13.05 psi)
mBST (σ = 20.31 psi)
mBST (σ =27.56 psi)
mBST (σ =34.81 psi)
5
0
0
50
100
150
200
250
Shear Displacement (in. x 10-3)
300
350
400
Figure B.4.23. BST and mBST generated shear stress-displacement relationships for ISU6
and ISU7 at 50.3-ft depth
139
9
τ = 0.65σ + 1.02
φ = 33.02º; c = 1.02 psi (BST)
7
6
5
4
τ = 0.52σ + 0.22
α = 27.38º; a = 0.22 psi (mBST)
3
2
1
0
0
2
4
6
8
Normal Stress,σ (psi)
10
12
14
Figure B.4.24. ISU8 at 9-ft depth (BST & mBST)
8
Shear Stress,τ (psi)
7
τ = 0.25σ + 1.93
φ = 14.04º; c = 1.93 psi (BST)
6
5
4
τ = 0.0004σ + 3.91
α = 0º; a = 3.91 psi (mBST)
3
2
1
0
0
5
10
15
Normal Stress,σ (psi)
20
25
Figure B.4.25. ISU8 at 23-ft depth (BST & mBST)
16
14
Shear Stress,τ (psi)
Shear Stress,τ (psi)
8
τ = 0.32σ + 2.80
φ = 17.97º; c = 2.80 psi (mBST)
12
10
8
τ = 0.019σ + 7.62
α = 1.07º; a = 7.62 psi (BST)
6
4
2
0
0
10
20
Normal Stress,σ (psi)
30
Figure B.4.26. ISU8 at 45-ft depth (BST & mBST)
140
40
9
8
Shear Stress (psi)
7
6
5
4
3
BST (σ = 2.90 psi)
BST (σ = 5.80 psi)
BST (σ = 11.60 psi)
mBST (σ = 2.90 psi)
mBST (σ = 5.80 psi)
mBST (σ = 11.60 psi)
2
1
0
0
50
100
150
200
Shear Displacement (in. x 10-3)
250
300
Figure B.4.27. BST and mBST generated shear stress-displacement relationships for ISU8
at 9-ft depth
8
7
Shear Stress (psi)
6
5
4
3
BST (σ = 7.25 psi)
BST (σ = 14.50 psi)
BST (σ = 21.76 psi)
mBST (σ = 7.25 psi)
mBST (σ = 14.50 psi)
mBST (σ = 21.76 psi)
2
1
0
0
50
100
150
200
Shear Displacement (in. x 10-3)
250
300
Figure B.4.28. BST and mBST generated shear stress-displacement relationships for ISU8
at 23-ft depth
141
16
14
Shear Stress (psi)
12
10
8
6
BST (σ =14.50 psi)
BST (σ = 21.76 psi)
BST (σ = 36.26 psi)
mBST (σ = 14.50 psi)
mBST (σ = 21.76 psi)
mBST (σ = 36.26 psi)
4
2
0
0
50
100
150
200
Shear Displacement (in. x 10-3)
250
300
350
Figure B.4.29. BST and mBST generated shear stress-displacement relationships for ISU8
at 45-ft depth
142
B.5. Soil Classification and Properties Obtained from Gradation and Atterberg Limit Tests
Table B.5.1. Soil classification and properties for ISU1 from gradation and Atterberg limit
tests
Disturbed
Sample
Sample
Depth
(ft)
Soil
Type
(USCS)
D10
(in)
D30
(in)
D60
(in)
Liquid
Limit, LL
(%)
Plasticity
Index, PI
(%)
Moisture
Content, ω
(%)
DS-1
DS-2
DS-3
DS-4
DS-5
0 to 2
6 to 7
14 to 15
15
21
ML
CL
CL
CL
CL
n/a
n/a
n/a
n/a
n/a
1.2E-4
1.5E-4
4.1E-4
1E-4
8.8E-5
7.8E-4
8.4E-4
2.8E-3
2.8E-3
5.8E-3
42.10
44.40
27.90
32.50
39.10
10.40
17.90
7.40
17.70
21.60
-
Saturated
Unit
Weight,
γsat (pcf)
-
Void
Ratio,
e
-
Table B.5.2. Soil classification and properties for ISU2 from gradation and Atterberg limit
tests
Disturbed
Sample
Sample
Depth
(ft)
Soil
Type
(USCS)
D10
(in)
D30
(in)
D60
(in)
Liquid
Limit, LL
(%)
Plasticity
Index, PI
(%)
Moisture
Content, ω
(%)
DS-1
DS-2
DS-3
DS-4
DS-5
DS-6
10
20
30
55
60
65
SC
CL
CL
CL
CL
CL
n/a
n/a
n/a
n/a
n/a
n/a
4.8E-4
1.7E-4
2.7E-4
3.3E-4
4.7E-4
1.8E-3
5.9E-3
2.6E-3
1.7E-3
2.5E-3
2.5E-3
2.8E-3
28.67
43.74
43.16
47.54
45.54
28.75
13.39
25.04
19.21
28.40
24.72
7.81
30.00
12.49
9.58
10.71
13.31
Saturated
Unit
Weight,
γsat (pcf)
121.01
141.73
146.68
144.69
140.44
Void
Ratio,
e
0.81
0.34
0.26
0.29
0.36
Table B.5.3. Soil classification and properties for ISU3 from gradation and Atterberg limit
tests
Disturbed
Sample
Sample
Depth
(ft)
Soil
Type
(USCS)
D10
(in)
D30
(in)
D60
(in)
Liquid
Limit, LL
(%)
Plasticity
Index, PI
(%)
Moisture
Content, ω
(%)
DS-1
DS-2
DS-3
DS-4
DS-5
DS-6
DS-7
2 to 4
15
26
35
50
60
65
CL
SM
SM-SC
CL
CL
CL
SM
n/a
1.4E-4
n/a
n/a
n/a
n/a
n/a
4.9E-4
7.3E-3
1.3E-3
2.9E-4
1.9E-4
4.8E-4
8.3E-4
2.7E-3
4E-2
1.3E-2
2.4E-3
1.5E-3
4.2E-3
8.2E-3
36.49
19.39
21.40
30.63
28.20
23.46
21.85
18.69
4.53
10.79
8.15
9.37
2.90
23.03
29.39
30.35
32.57
20.34
16.47
143
Saturated
Unit
Weight,
γsat (pcf)
127.81
121.54
120.70
118.84
130.87
135.83
Void
Ratio,
e
0.62
0.79
0.82
0.88
0.55
0.44
Table B.5.4. Soil classification and properties for ISU4 from gradation and Atterberg limit
tests
Disturbed
Sample
Sample
Depth
(ft)
Soil
Type
(USCS)
D10
(in)
D30
(in)
D60
(in)
Liquid
Limit, LL
(%)
Plasticity
Index, PI
(%)
Moisture
Content, ω
(%)
DS-1
DS-2
DS-3
DS-4
3.5 to 5
8.5 to 10
15
18.5 to 20
CL
SW-SC
SM
SW
n/a
2.9E-3
3.7E-4
3.5E-3
6.5E-4
8.7E-3
5.9E-3
1.7E-2
4.5E-3
2.2E-2
2.4E-2
4.5E-2
29.32
29.32
12.33
-
11.41
-
25.36
17.18
22.12
15.46
Saturated
Unit
Weight,
γsat (pcf)
125.37
134.86
128.81
137.24
DS-5
DS-6
DS-7
DS-8
DS-9
DS-10
23.5 to 25
33 to 35
40
50
55
65
CL
CL
CL
CL
CL
CL
n/a
n/a
n/a
n/a
n/a
n/a
2.4E-4
1E-4
3.3E-4
3.3E-4
4E-4
3.3E-4
2.9E-3
2.4E-3
3.3E-3
4.2E-3
4E-3
3.3E-3
27.49
38.68
29.38
25.98
25.33
29.63
13.46
22.70
16.70
13.19
13.06
15.76
12.65
16.86
15.75
15.09
13.12
14.73
141.48
135.30
136.83
137.77
140.74
138.29
Void
Ratio,
e
0.68
0.46
0.60
0.42
0.34
0.46
0.43
0.41
0.35
0.40
Table B.5.5. Soil classification and properties for ISU5 from gradation and Atterberg limit
tests
Disturbed
Sample
Sample
Depth
(ft)
Soil
Type
(USCS)
D10
(in)
D30
(in)
D60
(in)
Liquid
Limit, LL
(%)
Plasticity
Index, PI
(%)
Moisture
Content, ω
(%)
DS-1
DS-2
DS-3
DS-4
DS-5
DS-6
DS-7
DS-8
DS-9
3
8 to 10
10 to 12
16
28 to 30
37 to 38.5
38.5 to 40
43.5 to 45
48 to 50
SC
ML
CL
CL
CL
CL
SC
CL
CL
3.3E-5
9.0E-6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
8.1E-4
4.8E-4
2.4E-4
3.4E-4
3.4E-4
3.4E-4
7.2E-4
1.2E-4
1E-4
2.1E-2
2.7E-3
2.6E-3
2.7E-3
2.8E-3
2.7E-3
6.4E-3
2.6E-3
2.4E-3
26.31
36.30
38.41
49.10
44.60
38.61
22.02
38.73
40.07
11.27
5.57
20.82
27.08
26.84
22.23
8.63
20.78
22.33
20.39
18.70
20.64
21.58
17.20
22.03
19.80
16.11
16.94
Saturated
Unit
Weight,
γsat (pcf)
130.82
132.89
130.52
129.42
134.84
128.92
131.52
136.32
135.19
Void
Ratio,
e
0.55
0.50
0.56
0.58
0.46
0.59
0.53
0.44
0.46
Table B.5.6. Soil classification and properties for ISU6 & ISU7 from gradation and
Atterberg limit tests
Disturbed
Sample
Sample
Depth
(ft)
Soil
Type
(USCS)
D10
(in)
D30
(in)
D60
(in)
Liquid
Limit, LL
(%)
Plasticity
Index, PI
(%)
Moisture
Content, ω
(%)
DS-1
DS-2
DS-3
DS-4
DS-5
DS-6
DS-7
DS-8
5
14 to 15
19.5
29 to 30
34 to 35
39 to 40
54 to 55
64 to 65
SC
SM
CL
CL
CL
CL
ML
CL
9E-5
9E-5
n/a
n/a
n/a
n/a
n/a
n/a
2.6E-3
2.8E-3
4.2E-4
6.3E-4
4.7E-4
4.6E-3
3.7E-4
4.8E-3
1.8E-2
2.4E-2
2.8E-3
3.7E-3
3.8E-3
4.2E-3
1.3E-3
2.7E-3
24.81
18.16
24.81
25.28
24.37
26.72
30.98
24.43
7.26
3.97
10.90
10.60
11.99
13.15
7.43
9.64
3.21
25.16
28.67
18.99
16.87
8.15
20.15
13.54
144
Saturated
Unit
Weight,
γsat (pcf)
160.01
125.56
122.19
132.52
135.28
149.35
131.10
140.09
Void
Ratio,
e
0.09
0.68
0.77
0.51
0.46
0.22
0.54
0.37
Table B.5.7. Soil classification and properties for ISU8 from gradation and Atterberg limit
tests
Disturbed
Sample
Sample
Depth
(ft)
Soil
Type
(USCS)
D10
(in)
D30
(in)
D60
(in)
Liquid
Limit, LL
(%)
Plasticity
Index, PI
(%)
Moisture
Content, ω
(%)
DS-1
DS-2
DS-3
DS-4
3.5 to 5
10 to 11
15 to 16
18 to 19
CL
CL
CL
CL
n/a
n/a
n/a
n/a
3.3E-4
3.3E-4
3.3E-4
4.1E-4
2.3E-3
2.3E-3
2.4E-3
2.4E-3
39.77
43.26
43.53
42.25
16.69
19.57
22.12
20.85
9.97
12.69
14.03
10.29
Saturated
Unit
Weight,
γsat (pcf)
145.98
141.41
139.34
145.42
DS-5
21.5 to 23
CL
n/a
1.9E-4
8.7E-4
43.14
22.17
13.25
140.53
0.36
DS-6
DS-7
DS-8
DS-9
DS-10
30 31
48.5 to 50
53.5 to 55
58.5 to 60
63.5 to 65
SW
CL
CL
CL
CL
1.9E-3
n/a
n/a
5.5E-5
5E-5
1.4E-2
3.3E-4
6.3E-4
6.9E-4
5.5E-4
4.5E-2
2.8E-3
4.2E-3
5.2E-3
4.9E-3
34.14
34.14
24.24
23.29
17.45
17.45
13.35
10.20
10.73
7.63
3.09
5.51
5.23
144.65
150.36
160.31
154.74
155.35
0.29
0.21
0.08
0.15
0.14
Void
Ratio,
e
0.27
0.34
0.38
0.28
Table B.5.8. Soil classification and properties for ISU9 from gradation and Atterberg limit
tests
Disturbed
Sample
Sample
Depth
(ft)
Soil
Type
(USCS)
D10
(in)
D30
(in)
D60
(in)
Liquid
Limit, LL
(%)
Plasticity
Index, PI
(%)
Moisture
Content, ω
(%)
DS-1
DS-2
DS-3
DS-4
DS-5
DS-6
DS-7
DS-8
DS-9
3.5 to 5
8.5 to 10
13 to 15
18 to 20
30
40
50
55
60
SM; SC
CL
SM; SC
SW
SW
SP
SW
SM; SC
SW
9E-5
5E-4
7.3E-3
7E-3
7E-3
6.7E-3
1E-4
8.2E-3
2.5E-3
2.6E-3
9.8E-3
2E-2
2.1E-2
1.6E-2
2.1E-2
2.7E-3
2.3E-2
9.8E-3
2.8E-3
3.3E-2
4.7E-2
5E-2
4E-2
5.2E-2
2.2E-2
4.9E-2
-
-
23.63
24.40
28.48
18.26
23.64
28.40
17.87
27
17.94
Saturated
Unit
Weight,
γsat (pcf)
19.98
19.85
19.23
20.97
19.98
19.24
21.05
19.45
21.04
Void
Ratio,
e
0.64
0.66
0.77
0.49
0.64
0.77
0.48
0.73
0.48
Table B.5.9. Soil classification and properties for ISU10 from gradation and Atterberg
limit tests
Disturbed
Sample
Sample
Depth
(ft)
Soil
Type
(USCS)
DS-1
3.5 to 5
DS-2
8.5 to 10
DS-3
DS-4
DS-5
13 to 15
18 to 20
30
DS-6
40
DS-7
50
SW
SP-SM
SP-SC
SW
SP
SW
SW-SM
SW-SC
SW
D10
(in)
D30
(in)
D60
(in)
Liquid
Limit, LL
(%)
Plasticity
Index, PI
(%)
Moisture
Content, ω
(%)
6E-3
2.3E-2
5.6E-2
-
-
14.64
Saturated
Unit
Weight,
γsat (pcf)
138.43
4E-3
7.5E-3
1.5E-2
-
-
13.79
139.70
0.37
9.4E-3
1.8E-2
7.7E-3
3.3E-2
3.9E-2
2.7E-2
5.7E-2
5.9E-2
5.6E-2
-
-
15.00
18.01
10.37
137.90
133.77
145.28
0.41
0.49
0.28
6.3E-3
2.8E-2
5.8E-2
-
-
12.68
141.43
0.34
9.3E-3
3.4E-2
6E-2
-
-
6.59
152.46
0.18
145
Void
Ratio,
e
0.40
B.6. Total Lateral Earth and Pore Water Pressure Measurements using Push-in Pressure
Cells (PCs)
60
9
Earth Pressure (PC1)
8
Pile Reaches PC
40
6
5
30
Hydrostatic Pressure, μ
4
20
3
Geostatic Vertical Pressure, σv
0
-30
-20
BOR2
BOR3
2
EOD
BOR1
10
Pore Water Pressure (psi)
7
Pile Driving
Begin
Total Lateral Esrth Pressure (psi)
Water Pressure (PC1)
50
1
0
-10
0
10
Time After the End of Driving (Minute)
20
30
60
9
Earth Pressure (PC1)
8
Water Pressure (PC1)
Peak Pressures
EP (PC1): 48 psi
WP (PC1): 5.6 psi
7
40
6
5
30
Hydrostatic Pressure, μ
4
20
3
Geostatic Vertical Pressure, σv
2
BOR3
10
Pore Water Pressure (psi)
Total Lateral Esrth Pressure (psi)
50
1
0
0
-0.5
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
Time After the End of Driving (Day)
0.3
0.4
0.5
Figure B.6.1. Total lateral earth and pore water pressure measurements from PC1 at test
pile ISU7
146
50
10
Earth Pressure (PC4)
7
30
6
20
15
10
5
BOR2
25
BOR1
35
EOD
8
Pile Reaches PC
40
4
3
2
Geostatic Vertical Pressure, σv
5
1
Hydrostatic Pressure, μ
0
-30
-20
-10
0
10
Time After End of Driving (Minute)
0
20
30
50
10
Earth Pressure (PC4)
9
Water Pressure (PC4)
40
8
35
7
30
6
25
5
20
4
15
3
0
-2
0
2
Hydrostatic Pressure, μ
4
6
8
10
12
Time After End of Driving (Day)
14
2
SLT End
SLT Begin
BOR5
BOR3
BOR4
5
BOR6
Geostatic Vertical Pressure, σv
10
Pore Water Pressure (psi)
Peak Pressures
EP (PC1): 45 psi
WP (PC1): 3 psi
45
Total Lateral Earth Pressure (psi)
Pore Water Pressure (psi)
9
Water Pressure (PC4)
Pile Driving Begin
Total Lateral Earth Pressure (psi)
45
1
0
16
18
Figure B.6.2. Total lateral earth and pore water pressure measurements from PC4 at test
pile ISU8
147
8
7
6
25
5
20
4
Hydrostatic Pressure, μ
15
3
Geostatic Vertical Pressure, σv
10
Pore Water Pressure (psi)
30
9
Water Pressure (PC4)
BOR2
35
Earth Pressure (PC4)
BOR1
Total Lateral Earth Pressure (psi)
40
10
EOD
Driving Begin
45
Pile Reaches PC
50
2
5
1
0
0
-50
-40
-30
-20
-10
0
Time After End of Driving (Minute)
10
20
50
10
Earth Pressure (PC4)
45
9
Water Pressure (PC4)
7
6
25
5
20
4
Hydrostatic Pressure, μ
15
3
Geostatic Vertical Pressure, σv
10
Pore Water Pressure (psi)
SLT End
SLT Begin
30
Peak Pressures
EP (PC4): 39.5 psi
WP (PC4): 4.5 psi
BOR5
35
BOR4
8
BOR3
Total Lateral Earth Pressure (psi)
40
2
5
1
0
0
-1
0
1
2
3
4
Time After End of Driving (Day)
5
6
7
Figure B.6.3. Total lateral earth and pore water pressure measurements from PC4 at test
pile ISU10
148
APPENDIX C: DETAILS OF FULL-SCALE PILE TESTS
149
C.1. Locations of Strain Gauges along Test Piles
Pile head
Ground
2-1-60-E
2-1-60-W
Clay
(1' below ground)
2-VW-2-60-E
(6' below ground)
Clay
2-3-60-E
2-3-60-W
2-VW-8-120-E
(48' below ground)
(10' below ground)
Steel Angle Bar
3
(L 2 x 2 x 16
)
Clayey
Silt to
Silty Clay
Clayey
Silt to
Silty Clay
2-VW-4-60-E
(16' below ground)
(52' below ground)
2-10-120-E
2-10-120-W
(55' below gound)
Cable
Steel H-Pile
HP10x42
Silty
Clay to
Clay
2-9-120-E
2-9-120-W
Steel Angle Bar
3 ''
(L 2''x2''x16
)
2-5-60-E
2-5-60-W
Pile toe
(28' below ground)
2-VW-6-60-E
(30' below ground)
Normal
Strain Gauge
Clay
2-7-60-E
2-7-60-W
(39' below ground)
Figure C.1.1. Location of strain gauges along the ISU2 test pile at Mills County
150
Pile head
PK2-4-60-N (27' below ground)
PK2-4-60-S
Ground
Clayey
Silt to
Silty
Clay
PK2-1-30-N (2' below ground)
PK2-1-30-S
Normal
Strain Gauge
Steel Angle Bar
3 ''
(L 2''x2''x16
)
Cable
Clay
Steel H-Pile
HP10x42
Sandy
Silt to
Clayey
Silt
PK2-2-40-N (7' below ground)
PK2-2-40-S
Clayey
Silt to
Silty
Clay
Clayey
Silt to
Silty
Clay
PK2-5-80-N (37' below ground)
PK2-5-80-S
Steel Angle Bar
3
(L 2 x 2 x 16
)
PK2-6-80-N (42' below ground)
PK2-6-80-S
PK2-7-80-N (46' below ground)
PK2-7-80-S
PK2-3-60-N (17' below ground)
PK2-3-60-S
Clay
PK2-8-80-N (49' below ground)
PK2-8-80-S
Pile toe
Figure C.1.2. Location of strain gauges along the ISU3 test pile at Polk County
151
Pile head
Ground
JAS-5-60-E (38.8' below ground)
JAS-5-60-W
JAS-1-30-E (2.8' below ground)
JAS-1-30-W
Silty
Clay to
Clay
Steel Angle Bar
3
(L 2 x 2 x 16
)
Clay
JAS-6-60-E (35.8' below ground)
JAS-6-60-W
JAS-2-30-E (7.8' below ground)
JAS-2-30-W
Silty Sand
to Sandy
Silt
Sensitive
Fine
Grained
Normal
Strain Gauge
Silty
Clay to
Clay
Cable
JAS-7-60-E (42.8' below ground)
JAS-7-60-W
JAS-3-30-E (14.8' below ground)
JAS-3-30-W
Sandy
Silt to
Clayey
Silt
Steel Angle Bar
3 ''
(L 2''x2''x16
)
JAS-8-80-E (49.8' below ground)
JAS-8-80-W
Clayey
Silt to
Silty
Clay
Steel H-Pile
HP10x42
Silty Sand
to Sandy
Silt
JAS-9-80-E (52.8' below ground)
JAS-9-80-W
JAS-4-60-E (21.8' below ground)
JAS-4-60-W
Clay
JAS-10-80-E (55.8' below ground)
JAS-10-80-W
Pile toe
Figure C.1.3. Location of strain gauges along the ISU4 test pile at Jasper County
152
Pile head
Ground
Clay
Silty Sand
to Sandy
Silt
BUC-6-60-N (30' below ground)
BUC-6-60-S
BUC-1-30-N (3.2' below ground)
BUC-1-30-S
BUC-7-60-N (32' below ground)
BUC-7-60-S
BUC-2-30-N (5.2' below ground)
BUC-2-30-S
Silty
Clay to
Clay
Clay
Normal
Strain Gauge
BUC-3-30-N (10.5' below ground)
BUC-3-30-S
Steel Angle Bar
3
(L 2 x 2 x 16
)
BUC-8-60-N (41' below ground)
BUC-8-60-S
BUC-4-30-N (12.7' below ground)
BUC-4-30-S
Cable
Sand to
Silty Sand
Steel Angle Bar
3 ''
(L 2''x2''x16
)
Clayey
Silt to
Silty
Clay
Steel H-Pile
HP10x42
BUC-5-60-N (20.2' below ground)
BUC-5-60-S
BUC-9-80-N (48' below ground)
BUC-9-80-S
BUC-10-80-N (52' below ground)
BUC-10-80-S
Clay
BUC-11-80-N (56' below ground)
BUC-11-80-S
Pile toe
Figure C.1.4. Location of strain gauges along the ISU6 test pile at Buchanan County
153
Pile head
Ground
BUC-1-30-N (1' below ground)
BUC-1-30-S
Clay
BUC-2-30-N (11' below ground)
BUC-2-30-S
Normal
Strain Gauge
Sand to
Silty Sand
BUC-3-30-N (20' below ground)
BUC-3-30-S
Cable
Clay
Steel Angle Bar
3 ''
(L 2''x2''x16
)
Steel H-Pile
HP10x42
BUC-4-30-N (29.9' below ground)
BUC-4-30-S
Silty Sand
to Sandy
Silt
Silty
Clay to
Clay
BUC-5-60-N (35.9' below ground)
BUC-5-60-S
Pile toe
Figure C.1.5. Location of strain gauges along the ISU7 test pile at Buchanan County
154
Pile head
Ground
Silty Sand
to Sandy
Silt
POW-1-30-E (3.2' below ground)
POW-1-30-W
POW-6-60-E (29.2' below ground)
POW-6-60-W
POW-7-60-E (31.2' below ground)
POW-7-60-W
Steel Angle Bar
3
(L 2 x 2 x 16
)
Clay
Sand
POW-2-30-E (6.2' below ground)
POW-2-30-W
Normal
Strain Gauge
POW-8-60-E (38.2' below ground)
POW-8-60-W
Clayey
Silt to
Silty Clay
POW-3-30-E (12.2' below ground)
POW-3-30-W
POW-4-30-E (15.2' below ground)
POW-4-30-W
Cable
Silty
Clay to
Clay
Silty Sand
to Sandy
Silt
Steel Angle Bar
3 ''
(L 2''x2''x16
)
POW-9-80-E (45.2' below ground)
POW-9-80-W
Steel H-Pile
HP10x42
Clayey
Silt to
Silty Clay
POW-5-60-E (22.2' below ground)
POW-5-60-W
Silty
Clay to
Clay
Silty Sand
to Sandy
Silt
POW-10-80-E (53.2' below ground)
POW-10-80-W
POW-11-80-E (56.2' below ground)
POW-11-80-W
Pile toe
Figure C.1.6. Location of strain gauges along the ISU8 test pile at Poweshiek County
155
Pile head
Ground
Sandy
Silt to
Clayey
Silt
POW-4-60-E (30' below ground)
POW-4-60-W
POW-1-30-E (5' below ground)
POW-1-30-W
Steel Angle Bar
3
(L 2 x 2 x 16
)
Clay
POW-2-30-E (10' below ground)
POW-2-30-W
Normal
Strain Gauge
Sand
POW-3-30-E (20' below ground)
POW-3-30-W
POW-5-60-E (40' below ground)
POW-5-60-W
POW-6-60-E (45' below ground)
POW-6-60-W
Cable
POW-7-80-E (49' below ground)
POW-7-80-W
Steel Angle Bar
3 ''
(L 2''x2''x16
)
Sand
Pile toe
Steel H-Pile
HP10x42
Figure C.1.7. Location of strain gauges along the ISU9 test pile at Des Moines County
156
Pile head
Ground
Sandy
Silt to
Clayey
Silt
Sand to
Silty
Sand
POW-4-60-E (34.2' below ground)
POW-4-60-W
POW-1-30-E (4.2' below ground)
POW-1-30-W
Steel Angle Bar
3
(L 2 x 2 x 16
)
Sandy
Silt to
Clayey
Silt
Normal
Strain Gauge
Sand
POW-5-60-E (44.2' below ground)
POW-5-60-W
POW-2-30-E (14.2' below ground)
POW-2-30-W
POW-6-60-E (46.2' below ground)
POW-6-60-W
Cable
Sand
POW-7-80-E (48.2' below ground)
POW-7-80-W
Steel Angle Bar
3 ''
(L 2''x2''x16
)
Pile toe
Steel H-Pile
HP10x42
POW-3-60-E (24.2' below ground)
POW-3-60-W
Figure C.1.8. Location of strain gauges along the ISU10 test pile at Cedar County
157
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
Mahaska
steel H test
10x57
P DA O P : Fra me
C.2. Pile Driving Analyzer (PDA) Measurements
400
kips
BN 174
12/18/2007 9:58:24 AM
RTL
239 kips
RSP
0 kips
RMX
141 kips
EMX
16.5 k-ft
ETR
38.9 (%)
STK
6.35 ft
C SX
24.5 ksi
TSX
1.7 ksi
BTA
100.0 (%)
13.3
f/s
ISU1-EOD
F
V
LE
33.00
AR
16.80
102.4ms
EM
30000
SP
0.492
W S 16807.9
EA/C
30.0
P ILE DRIVING ANALYZER ®
LP
1.00
Ve rsio n 2001.086
4.00 ms
IOWA DOT
ISU2
Figure
P DA O P : FRAME
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
C.2.1. PDA force and velocity records
for ISU1
MILLS TEST
DRIVING
F12 A12
HP10X42 STEEL PILE 60FT LONG
400
kips
F1: [2355] 86 (1)
BN 1/236
F2: [2356] 89 (1)
7/14/2008 12:26:07 P M
A1: [42695] 1060 g's/v (1)
RTL
205 kips
A2: [41315] 1105 g's/v (1)
RSP
0 kips
RMX
105 kips
EMX
20.1 k-ft
ETR
46.5 (%)
STK
5.94 ft
C SX
29.4 ksi
TSX
4.0 ksi
BTA
100.0 (%)
18.1
f/s
ISU2-EOD
F
V
LE
58.00 ft
AR
12.40 in^2
102.4ms
EM
30000 ksi
SP
0.492 k/ft3
P ILE DRIVING ANALYZER ®
W S 16807.9 f/s
Ve rsio n 2001.086
EA/C
22.1 kse c/ft
MILLS TEST (RESTRIKE
1)ft
LP
54.00
IOWA DOT
6.90 ms
ISU2
P DA O P : FRAME
HP10X42 STEEL PILE 60FT LONG
400
kips
ISU2-1st Re-strike
F
F12 A12
BN 6
7/14/2008 4:26:05 P M
F1: [2355] 87 (1)
RTL
271 kips
F2: [2356] 89 (1)
RSP
0 kips
A1: [41309] 1095 g's/v (1)
RMX
148 kips
A2: [41315] 1115 g's/v (1)
EMX
19.3 k-ft
ETR
44.5 (%)
STK
6.48 ft
C SX
31.5 ksi
TSX
1.9 ksi
BTA
100.0 (%)
18.1
f/s
V
102.4ms
6.90 ms
LE
58.00 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
54.00 ft
F12
158
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU2
MILLS TEST (RESTRIKE 2)
HP10X42 STEEL PILE 60FT LONG
P DA OP : FRAME
400
kips
nd
ISU2-2 Re-strike
F
BN 5/4
7/15/2008 10:27:43 AM
RTL
328 kips
RSP
48 kips
RMX
162 kips
EMX
21.0 k-ft
ETR
48.5 (%)
STK
7.29 ft
CSX
32.8 ksi
TSX
0.4 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
58.00 ft
AR
12.40 in^2
102.4ms
EM
30000 ksi
SP
0.492 k/ft3
P ILE DRIVING ANALYZER
®
W S 16807.9
f/s
Ve rsio n 2001.086
EA/C
22.1 kse c/ft
MILLS TEST (RESTRIKE
3)ft
LP
55.33
IOWA DOT
6.90 ms
ISU2
P DA O P : FRAME
HP10X42 STEEL PILE 60FT LONG
400
kips
rd
ISU2-3 Re-strike
F
F12 A12
BN 6/5
7/17/2008 11:45:26 AM
F1: [2355] 87 (1)
RTL
359 kips
F2: [2356] 89 (1)
RSP
96 kips
A1: [41309] 1095 g's/v (1)
RMX
146 kips
A2: [41315] 1115 g's/v (1)
EMX
19.4 k-ft
ETR
45.0 (%)
STK
7.15 ft
C SX
33.6 ksi
TSX
0.5 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
58.00
AR
12.40
102.4ms
EM
30000
SP
0.492
W S 16807.9
PILE DRIVING ANALYZER
®
EA/C
22.1
Ve rsion 2001.086
LP
55.83
6.90 ms
IOWA DOT
ISU3
PDA OP: kam
Figure
400
kips
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
isu3polkEOD
C.2.2. PDA force and velocity records
for ISU2
F12 A12
HP10X42 STEEL PILE LONG
ISU3-EOD
F
F1:
BN[2355]
273 87 (1)
F2: [2356] 89 (1)
1/7/2009 10:21:18 AM
A1: [41309] 1095 g's/v (1)
RTL[41315]237
kips
A2:
1115
g's/v (1)
18.1
f/s
RSP
RMX
EMX
ETR
STK
CSX
TSX
BTA
V
102.4ms
6.84 ms
kips
kips
k-ft
(%)
ft
ksi
ksi
(%)
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
F12
159
0
120
19.8
46.6
5.76
25.9
1.1
100.0
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU3
isu3polkrestrike1
HP10X42 STEEL PILE LONG
P DA O P : ka m
400
kips
st
ISU3-1 Re-strike
F
BN 4
1/7/2009 10:25:45 AM
RTL
245 kips
RSP
0 kips
RMX
117 kips
EMX
18.9 k-ft
ETR
44.5 (%)
STK
5.86 ft
C SX
26.0 ksi
TSX
1.2 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
isu3polkrestrike2
LP
48.00
IOWA DOT
6.84 ms
ISU3
P DA O P : ka m
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
HP10X42 STEEL PILE LONG
400
kips
ISU3-2nd Re-strike
F
F12 A12
BN 4
1/7/2009
F1: [2355]10:32:10
87 (1) AM
RTL
F2: [2356]251
89 kips
(1)
RSP
kips g's/v (1)
A1: [41309] 0
1095
RMX
123
kips g's/v (1)
A2: [41315]
1115
EMX
19.1 k-ft
ETR
45.0 (%)
STK
5.92 ft
C SX
26.5 ksi
TSX
0.9 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
W S 16807.9
P ILE DRIVING ANALYZER
®
EA/C
22.1
Ve rsio n 2001.086
LP
48.50
isu3polkrestrike3
6.84 ms
IOWA DOT
ISU3
P DA O P : ka m
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
HP10X42 STEEL
F12PILE
A12LONG
400
kips
ISU3-3rd Re-strike
F
BN 5
F1:
[2355]10:45:32
87 (1)
1/7/2009
AM
F2:
89 (1)
RTL[2356]262
kips
A1:
RSP[41309] 1095
0 kipsg's/v (1)
A2:
1115
RMX[41315]
128
kipsg's/v (1)
EMX
19.2 k-ft
ETR
45.3 (%)
STK
6.07 ft
C SX
26.9 ksi
TSX
0.0 ksi
BTA
100.0 (%)
18.1
f/s
V
102.4ms
6.84 ms
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
49.00 ft
F12
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
160
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU3
isu3polkrestrike4
HP10X42 STEEL PILE LONG
P DA O P : ka m
400
kips
ISU3-3rd Re-strike
F
BN 2
1/8/2009 1:57:08 P M
RTL
314 kips
RSP
0 kips
RMX
157 kips
EMX
20.2 k-ft
ETR
47.6 (%)
STK
6.79 ft
C SX
28.0 ksi
TSX
1.6 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086EA/C
22.1
LP
49.50
isu3polkrestrike5
IOWA DOT
6.84 ms
ISU3
P DA O P : ka m
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
HP10X42 STEEL PILE LONG
400
kips
ISU3-4th Re-strike
F
F12 A12
BN 8
1/9/2009
10:08:29
F1: [2355]
87 (1) AM
RTL
336
F2: [2356]
89kips
(1)
RSP
kips g's/v (1)
A1: [41309]0 1095
RMX
163 1115
kips g's/v (1)
A2: [41315]
EMX
17.6 k-ft
ETR
41.5 (%)
STK
7.06 ft
C SX
28.2 ksi
TSX
0.9 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
W S 16807.9
EA/C
P ILE DRIVING ANALYZER
®22.1
50.33
Ve rsio n 2001.086LP
6.84 ms
IOWA DOT
ISU4
P DA O P : ka m
Figure
400
kips
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
isu4driving
C.2.3. PDA force and velocity records
for ISU3
F12
A12
HP10X42 STEEL PILE
LONG
ISU4-EOD
F
F1: [2355]
87 (1)
BN
231
F2: [2356] 3:08:17
89 (1) P M
4/22/2009
A1: [41309]
RTL
2681095
kips g's/v (1)
A2: [41315] 01115
RSP
kips g's/v (1)
RMX
143 kips
EMX
16.8 k-ft
ETR
38.7 (%)
STK
6.46 ft
C SX
28.8 ksi
TSX
2.7 ksi
BTA
100.0 (%)
18.1
f/s
V
102.4ms
6.84 ms
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
F12
161
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU4
isu41st bor
HP10X42 STEEL PILE LONG
P DA OP : ka m
400
kips
ISU4-1st Re-strike
F
BN 5
4/22/2009 3:14:07 P M
RTL
273 kips
RSP
1 kips
RMX
144 kips
EMX
17.0 k-ft
ETR
39.3 (%)
STK
6.51 ft
CSX
28.7 ksi
TSX
2.1 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
ft
in^2
ksi
k/ft3
f/s
kse c/ft
55.00 ft
IOWA DOT
6.84 ms
ISU4
isu4 2nd bor LP
HP10X42 STEEL PILE LONG
P DA OP : ka m
400
kips
ISU4-2nd Re-strike
F
F12 A12
BN 3
4/22/2009
3:31:03
PM
F1:
[2355] 87
(1)
RTL [2356]284
kips
F2:
89 (1)
RSP[41309] 1095
9 kipsg's/v (1)
A1:
RMX[41315]
143
kipsg's/v (1)
A2:
1115
EMX
18.7 k-ft
ETR
43.2 (%)
STK
6.63 ft
CSX
29.1 ksi
TSX
1.3 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
PILE DRIVING ANALYZER
®
W S 16807.9
Ve rsion 2001.086
EA/C
22.1
ft
in^2
ksi
k/ft3
f/s
kse c/ft
55.33 ft
IOWA DOT
6.84 ms
ISU4
isu4 3rd bor LP
HP10X42 STEEL PILE LONG
PDA OP: kam
400
kips
ISU4-3rd Re-strike
F
F12 A12
BN 3
4/22/2009
4:07:19
F1:
[2355] 87
(1) PM
RTL [2356]293
kips
F2:
89 (1)
RSP [41309]18
kips g's/v (1)
A1:
1095
A2:
1115
RMX[41315]
154
kips g's/v (1)
EMX
19.5 k-ft
ETR
45.0 (%)
STK
7.00 ft
CSX
30.7 ksi
TSX
1.1 ksi
BTA
100.0 (%)
18.1
f/s
V
102.4ms
6.84 ms
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
55.70 ft
F12
162
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU4
isu4 4th bor
HP10X42 STEEL PILE LONG
P DA O P : ka m
400
kips
th
ISU4-4 Re-strike
F
BN 3
4/23/2009 8:54:03 AM
RTL
379 kips
RSP
98 kips
RMX
161 kips
EMX
22.2 k-ft
ETR
51.4 (%)
STK
8.97 ft
C SX
35.3 ksi
TSX
1.1 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
PILE DRIVING ANALYZER
®
W
S
16807.9
Ve rsion 2001.086
EA/C
22.1
isu4 5th bor LP
56.00
IOWA DOT
6.84 ms
ISU4
PDA OP: ka m
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
HP10X42 STEEL PILE LONG
F12
400
kips
th
ISU4-5 Re-strike
F
A12
BN 6
4/24/2009
8:50:19
AM
F1:
[2355] 87
(1)
RTL [2356]387
kips
F2:
89 (1)
RSP [41309]
154
kipsg's/v (1)
A1:
1095
RMX[41315]
162
kipsg's/v (1)
A2:
1115
EMX
18.2 k-ft
ETR
42.1 (%)
STK
7.48 ft
CSX
32.5 ksi
TSX
0.1 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER ®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
isu4 6th bor LP
56.30
IOWA DOT
6.84 ms
ISU4
P DA OP : ka m
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
HP10X42 STEEL PILE LONG
400
kips
ISU4-6th Re-strike
F
F12 A12
BN 11
4/27/2009 9:12:26 AM
F1: [2355]407
87 kips
(1)
RTL
F2:
[2356]
89
(1)
RSP
223 kips
A1: [41309]
RMX
2231095
kips g's/v (1)
A2: [41315]
EMX
15.01115
k-ft g's/v (1)
18.1
f/s
V
ETR
STK
CSX
TSX
BTA
102.4ms
6.84 ms
(%)
ft
ksi
ksi
(%)
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
56.67 ft
Figure C.2.4. PDA force and velocity records for ISU4
F12
163
34.8
7.39
29.9
1.0
100.0
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
PILE DRIVING ANALYZER ®
Ve rsion 2001.086
ISU5
isu5 driving
HP10X42 STEEL PILE LONG
PDA OP: ka m
400
kips
ISU5-EOD
F
BN 603
5/19/2009 12:11:55 P M
RTL
413 kips
RSP
200 kips
RMX
200 kips
EMX
16.3 k-ft
ETR
40.5 (%)
STK
7.04 ft
CSX
31.9 ksi
TSX
1.0 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
isu5 1st restrike
IOWA DOT
6.84 ms
ISU5
P DA OP : ka m
ft
in^2
ksi
k/ft3
f/s
kse c/ft
HP10X42 STEEL PILE LONG
400
kips
ISU5-1st Re-strike
F
F12
BN 6A12
5/19/2009 12:19:40 P M
F1:
87 (1)
RTL [2355]428
kips
RSP[2356]224
kips
F2:
89 (1)
RMX[41309]
224
kipsg's/v (1)
A1:
1095
EMX[41315]
16.7
k-ft g's/v (1)
A2:
1115
ETR
41.6 (%)
STK
7.07 ft
CSX
32.0 ksi
TSX
1.0 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
isu5 2nd restrike
LP
54.00
IOWA DOT
6.84 ms
ISU5
P DA OP : ka m
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
HP10X42 STEEL PILE LONG
400
kips
F12 A12
BN 6
5/19/2009 12:30:00 P M
F1: [2355] 87 (1)
RTL
428 kips
F2: [2356] 89 (1)
RSP
229 kips
A1: [41309] 1095 g's/v (1)
RMX
229 kips
A2: [41315] 1115 g's/v (1)
EMX
15.8 k-ft
ETR
39.2 (%)
STK
6.96 ft
C SX
31.8 ksi
TSX
1.1 ksi
BTA
100.0 (%)
18.1
f/s
ISU5-2nd Re-strike
F
V
102.4ms
6.84 ms
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
55.30 ft
F12
164
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
PILE DRIVING ANALYZER ®
Ve rsion 2001.086
ISU5
isu5 3rd restrike
HP10X42 STEEL PILE LONG
PDA OP: ka m
400
kips
ISU5-3rd Re-strike
F
BN 12
5/19/2009 1:20:47 PM
RTL
442 kips
RSP
229 kips
RMX
229 kips
EMX
14.6 k-ft
ETR
36.4 (%)
STK
7.45 ft
CSX
33.3 ksi
TSX
4.1 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
W S 16807.9
P ILE DRIVING ANALYZER
®
Ve rsio n 2001.086EA/C
22.1
LP
55.70
isu5 4th restrike
6.84 ms
IOWA DOT
ISU5
P DA OP : ka m
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
HP10X42 STEEL PILE LONG
400
kips
th
ISU5-4 Re-strike
F
F12 A12
BN 6
5/20/2009
AM
F1: [2355]10:13:04
87 (1)
RTL
518
F2: [2356]
89 kips
(1)
RSP
3261095
kips g's/v (1)
A1: [41309]
RMX
3261115
kips g's/v (1)
A2: [41315]
EMX
18.9 k-ft
ETR
46.9 (%)
STK
8.20 ft
CSX
35.2 ksi
TSX
1.5 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsion 2001.086
EA/C
22.1
isu5 5th restrike
LP
56.00
IOWA DOT
6.84 ms
ISU5
P DA OP : ka m
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
HP10X42 STEEL PILE LONG
400
kips
th
ISU5-5 Re-strike
F
F12 A12
BN 7
5/22/2009
9:52:09
AM
F1:
[2355] 87
(1)
RTL[2356]563
kips
F2:
89 (1)
RSP[41309]
375
kipsg's/v (1)
A1:
1095
RMX[41315]
375
kipsg's/v (1)
A2:
1115
EMX
21.4 k-ft
ETR
53.1 (%)
STK
8.82 ft
CSX
37.0 ksi
TSX
2.8 ksi
BTA
100.0 (%)
18.1
f/s
V
102.4ms
6.84 ms
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
56.25 ft
F12
165
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU5
isu5 6th restrike
HP10X42 STEEL PILE LONG
P DA OP : ka m
400
kips
th
ISU5-6 Re-strike
F
BN 19
5/27/2009 10:09:46 AM
RTL
572 kips
RSP
400 kips
RMX
400 kips
EMX
20.3 k-ft
ETR
50.6 (%)
STK
8.69 ft
CSX
36.4 ksi
TSX
3.3 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
W S 16807.9
EA/C
22.1
LP
56.50
P ILE DRIVING ANALYZER
®
Ve rsio n 2001.086
F12 A12
6.84 ms
IOWA DOT
ISU6
P DA O P : KAM
Figure
ISU6 DRIVING
C.2.5. PDA force and velocity records
for ISU5
400
kips
HP10x42
ISU6-EOD
F
18.1
f/s
V
F1: [2355] 87 (1)
F2:
BN [2356]
268 89 (1)
A1:
[41309]
1095 g's/v
6/9/2009
3:26:47
P M (1)
A2:
1115
RTL [41315]
252
kipsg's/v (1)
RSP
0 kips
RMX
146 kips
EMX
15.9 k-ft
ETR
36.9 (%)
STK
6.33 ft
C SX
27.9 ksi
TSX
1.3 ksi
BTA
100.0 (%)
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
IOWA DOT
6.84 ms
ISU6
ISU6 1ST RESTRIKE
HP10x42
P DA O P : KAM
400
kips
ISU6-1st Re-strike
V
102.4ms
6.84 ms
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
55.00 ft
F12
166
ft
in^2
ksi
k/ft3
f/s
kse c/ft
F12 3A12
BN
6/9/2009 3:29:07 P M
F1: [2355]
87 kips
(1)
RTL
267
F2: [2356] 89
(1)
RSP
0 kips
A1: [41309]
RMX
1511095
kips g's/v (1)
A2: [41315]
EMX
17.51115
k-ft g's/v (1)
ETR
40.4 (%)
STK
6.85 ft
C SX
29.5 ksi
TSX
1.4 ksi
BTA
100.0 (%)
18.1
f/s
F
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
PILE DRIVING ANALYZER ®
Ve rsion 2001.086
ISU6
ISU6 2ND RESTRIKE
HP10x42
PDA OP: KAM
400
kips
ISU6-2nd Re-strike
F
BN 4
6/9/2009 3:33:06 P M
RTL
276 kips
RSP
0 kips
RMX
149 kips
EMX
17.1 k-ft
ETR
39.5 (%)
STK
6.86 ft
CSX
29.6 ksi
TSX
1.2 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
PILE DRIVING ANALYZER
®
W S 16807.9
Ve rsion 2001.086
EA/C
22.1
ISU6 3RD RESTRIKE
LP
55.60
6.84 ms
IOWA
DOT
ISU6
PDA OP: KAM
HP10x42
400
kips
ISU6-3rd Re-strike
F
18.1
f/s
V
IOWA DOT
ISU6
P DA OP : KAM
HP10x42
500
kips
F12 A12
BN 4
6/9/2009
F1:
[2355]3:43:40
87 (1) P M
RTL [2356]297
kips
F2:
89 (1)
RSP [41309]50
kipsg's/v (1)
A1:
1095
RMX[41315]
145
kipsg's/v (1)
A2:
1115
EMX
15.9 k-ft
ETR
36.7 (%)
STK
6.55 ft
CSX
28.7 ksi
TSX
0.6 ksi
BTA
100.0 (%)
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
W
S
16807.9
P ILE DRIVING ANALYZER ®
EA/C
22.1
Ve rsio n 2001.086
LP
56.00
ISU6 4th restrike
6.84 ms
th
ISU6-4 Re-strike
F
22.6
f/s
V
102.4ms
6.84 ms
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
F12 A12
BN 4
6/9/2009
F1:
[2355]5:03:26
87 (1) P M
RTL [2356]380
kips
F2:
89 (1)
RSP [41309]
101
kipsg's/v (1)
A1:
1095
RMX[41315]
167
kipsg's/v (1)
A2:
1115
EMX
23.0 k-ft
ETR
53.2 (%)
STK
8.26 ft
C SX
34.5 ksi
TSX
0.0 ksi
BTA
100.0 (%)
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
56.00 ft
F12
167
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU6
ISU6 5th restrike
HP10x42
P DA OP : KAM
400
kips
ISU6-5th Re-strike
BN 5
6/10/2009 11:18:56 AM
RTL
423 kips
RSP
176 kips
RMX
195 kips
EMX
21.0 k-ft
ETR
48.6 (%)
STK
8.20 ft
CSX
34.2 ksi
TSX
1.0 ksi
BTA
100.0 (%)
18.1
f/s
F
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
W S 16807.9
P ILE DRIVING ANALYZER
EA/C ® 22.1
Ve rsio n 2001.086LP
56.50
6.84 ms
IOWA DOT
ISU6
ISU6 6th restrike
F12
HP10x42
P DA OP : KAM
400
kips
ISU6-6th Re-strike
F
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
W S 16807.9
P ILE DRIVING ANALYZER
®
EA/C
22.1
Ve rsio n 2001.086
LP
56.33
ISU6 7th restrike
IOWA DOT
ISU6
P DA OP : KAM
HP10x42
400
kips
A12
F1: 5[2355] 87 (1)
BN
F2: [2356]11:06:41
89 (1) AM
6/12/2009
A1: [41309]
RTL
465 1095
kips g's/v (1)
A2: [41315]
RSP
230 1115
kips g's/v (1)
RMX
231 kips
EMX
22.1 k-ft
ETR
51.1 (%)
STK
8.47 ft
CSX
35.3 ksi
TSX
1.2 ksi
BTA
100.0 (%)
18.1
f/s
6.84 ms
ISU6-7th Re-strike
F
18.1
f/s
V
102.4ms
6.84 ms
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
F12 A12
BN 5
F1: [2355] 10:27:09
87 (1)
6/16/2009
AM
F2: [2356]485
89 kips
(1)
RTL
A1: [41309]
RSP
2661095
kips g's/v (1)
A2: [41315]
RMX
2661115
kips g's/v (1)
EMX
22.6 k-ft
ETR
52.2 (%)
STK
8.75 ft
CSX
35.0 ksi
TSX
1.0 ksi
BTA
100.0 (%)
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
57.00 ft
F12
168
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU6
ISU6 8th restrike
HP10x42
P DA OP : KAM
400
kips
ISU6-8th Re-strike
F
BN 4
6/19/2009 10:50:45 AM
RTL
514 kips
RSP
310 kips
RMX
310 kips
EMX
20.8 k-ft
ETR
48.0 (%)
STK
8.26 ft
CSX
35.6 ksi
TSX
1.2 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
W S 16807.9
EA/C
22.1
P ILE DRIVING ANALYZER ®
LP
57.30
Ve rsio n 2001.086
6.84 ms
IOWA DOT
ISU7
P DA O P : KAM
Figure
400
kips
ISU7 driving
C.2.6. PDA force and velocity records
for ISU6
F12
HP10x42
ISU7-EOD
F
A12
F1:
BN[2355]
10 87 (1)
F2:
[2356] 89
(1)
6/9/2009
4:20:32
PM
A1:
[41309]
1095
g's/v (1)
RTL
59 kips
A2:
[41315] 1115
g's/v (1)
RSP
0 kips
RMX
0 kips
EMX
17.7 k-ft
ETR
41.0 (%)
STK
0.00 ft
C SX
20.9 ksi
TSX
5.6 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
32.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
Ve rsio n 2001.086W S 16807.9
EA/C
22.1
3.87 ms DOT
IOWA
ISU7
ISU7 1st restrike
HP10x42
P DA O P : KAM
400
kips
ISU7-1st Re-strike
V
102.4ms
3.87 ms
LE
32.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
19.00 ft
F12
169
ft
in^2
ksi
k/ft3
f/s
kse c/ft
F12 2 A12
BN
6/9/2009 4:23:13 P M
F1: [2355] 80
87 kips
(1)
RTL
F2:
[2356]
89
(1)
RSP
0 kips
A1: [41309] 01095
RMX
kips g's/v (1)
A2: [41315]
EMX
13.01115
k-ft g's/v (1)
ETR
30.0 (%)
STK
0.00 ft
C SX
22.3 ksi
TSX
5.3 ksi
BTA
100.0 (%)
18.1
f/s
F
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU7
ISU7 2nd restrike
HP10x42
P DA OP : KAM
400
kips
ISU7-2nd Re-strike
F
BN 3
6/9/2009 4:29:09 P M
RTL
86 kips
RSP
0 kips
RMX
11 kips
EMX
12.6 k-ft
ETR
29.2 (%)
STK
0.00 ft
CSX
22.6 ksi
TSX
5.7 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
32.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
ISU7 3rd restrike
LP
20.00
3.87 ms
IOWA
DOT
ISU7
P DA OP : KAM
HP10x42
400
kips
ISU7-3rd Re-strike
F
18.1
f/s
V
IOWA DOT
ISU7
P DA OP : KAM
HP10x42
400
kips
th
ISU7-4 Re-strike
F
F12 A12
BN 4
6/9/2009
F1:
[2355]4:41:36
87 (1) P M
RTL[2356]103
kips
F2:
89 (1)
RSP
0
kipsg's/v (1)
A1: [41309] 1095
RMX[41315] 1115
6 kipsg's/v (1)
A2:
EMX
20.7 k-ft
ETR
47.9 (%)
STK
0.00 ft
CSX
24.0 ksi
TSX
4.2 ksi
BTA
100.0 (%)
LE
32.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsion 2001.086EA/C
22.1
LP
21.00
ISU7 4th restrike
3.87 ms
18.1
f/s
V
102.4ms
4.46 ms
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
F12 A12
BN 9
6/10/2009
F1: [2355]11:34:36
87 (1) AM
RTL
104
F2: [2356]
89kips
(1)
RSP
kips g's/v (1)
A1: [41309]0 1095
RMX
31 1115
kips g's/v (1)
A2: [41315]
EMX
10.5 k-ft
ETR
24.4 (%)
STK
4.35 ft
CSX
18.1 ksi
TSX
2.6 ksi
BTA
100.0 (%)
LE
37.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
22.50 ft
F12
170
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
PILE DRIVING ANALYZER ®
Ve rsion 2001.086
ISU7
ISU7 5th restrike
HP10x42
PDA OP: KAM
400
kips
ISU7-5th Re-strike
F
BN 5
6/12/2009 10:49:08 AM
RTL
150 kips
RSP
0 kips
RMX
66 kips
EMX
18.0 k-ft
ETR
41.7 (%)
STK
5.70 ft
CSX
23.3 ksi
TSX
2.4 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
37.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER ®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
ISU5 6th restrike
LP
34.50
IOWA DOT
4.46 ms
ISU5
P DA OP : KAM
HP10x42
400
kips
th
ISU7-6 Re-strike
F
F12 6A12
BN
6/16/2009 10:39:04 AM
F1: [2355]170
87 (1)
RTL
kips
F2:
[2356]
89
RSP
0 (1)
kips
A1: [41309]86
1095
RMX
kipsg's/v (1)
A2:
[41315]
1115
EMX
12.2 k-ft g's/v (1)
ETR
28.3 (%)
STK
5.15 ft
CSX
22.4 ksi
TSX
2.1 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
37.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086EA/C
22.1
ISU7 7th restrike
LP
35.50
IOWA DOT
4.46 ms
ISU7
P DA OP : KAM
HP10x42
400
kips
ISU7-7th Re-strike
F
18.1
f/s
V
102.4ms
4.60 ms
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
F12 A12
BN 8/7
6/19/2009
AM
F1: [2355] 10:32:57
87 (1)
RTL
192
kips
F2: [2356] 89 (1)
RSP
kips
A1: [41309]01095
g's/v (1)
RMX
93 kips
A2: [41315] 1115 g's/v (1)
EMX
16.8 k-ft
ETR
38.8 (%)
STK
5.92 ft
C SX
26.0 ksi
TSX
1.7 ksi
BTA
100.0 (%)
LE
37.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
26.00 ft
Figure C.2.7. PDA force and velocity records for ISU7
F12
171
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU8
ISU8 driving
HP10x42
P DA OP : KAM
400
kips
ISU8-EOD
F
BN 336
8/6/2009 9:16:32 AM
RTL
304 kips
RSP
18 kips
RMX
164 kips
EMX
18.8 k-ft
ETR
43.6 (%)
STK
6.76 ft
CSX
32.6 ksi
TSX
1.6 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
ISU8 1st restrike
IOWA DOT
6.84 ms
ISU8
P DA OP : KAM
ft
in^2
ksi
k/ft3
f/s
kse c/ft
HP10x42
400
kips
ISU8-1st Re-strike
F
F12
BN 6A12
8/6/2009 9:26:43 AM
F1:
87 (1)
RTL [2355]330
kips
F2:
RSP [2356] 89
56 (1)
kips
A1:
1095
RMX[41309]
161
kipsg's/v (1)
A2:
1115
EMX[41315]
18.7
k-ft g's/v (1)
ETR
43.2 (%)
STK
6.82 ft
CSX
32.9 ksi
TSX
1.6 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
LP
55.00
ISU8 2nd restrike
IOWA DOT
6.84 ms
ISU8
P DA OP : KAM
HP10x42
400
kips
nd
ISU8-2 Re-strike
F
18.1
f/s
V
102.4ms
6.84 ms
F12 A12
BN 4
8/6/2009
F1:
[2355]9:32:40
87 (1) AM
RTL [2356]342
kips
F2:
89 (1)
RSP [41309]63
kipsg's/v (1)
A1:
1095
RMX[41315]
169
kipsg's/v (1)
A2:
1115
EMX
19.8 k-ft
ETR
45.8 (%)
STK
7.15 ft
CSX
33.8 ksi
TSX
1.5 ksi
BTA
100.0 (%)
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
55.50 ft
F12
172
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU8
ISU8 3rd restrike
HP10x42
P DA OP : KAM
400
kips
ISU8-3rd Re-strike
F
BN 4
8/6/2009 10:12:27 AM
RTL
361 kips
RSP
92 kips
RMX
161 kips
EMX
19.1 k-ft
ETR
44.2 (%)
STK
7.11 ft
CSX
34.1 ksi
TSX
1.1 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
LP
56.16
ISU8 4th restrike
IOWA DOT
6.84 ms
ISU8
P DA OP : KAM
HP10x42
400
kips
ISU8-4th Re-strike
F
18.1
f/s
V
F12 A12
BN 5
8/7/2009
F1:
[2355] 8:28:44
87 (1) AM
RTL[2356] 380
kips
F2:
89 (1)
RSP[41309]161
kips
A1:
1095
g's/v (1)
RMX
kips
A2:
[41315]180
1115
g's/v (1)
EMX
18.0 k-ft
ETR
41.7 (%)
STK
7.39 ft
CSX
30.8 ksi
TSX
0.6 ksi
BTA
100.0 (%)
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsion 2001.086EA/C
22.1
IOWA DOT
6.84 ms
ISU8
ISU8 5th restrike
LP
HP10x42
P DA OP : KAM
400
kips
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
ISU8-5th Re-strike
F
F12 A12
BN 4
8/10/2009
F1: [2355]8:31:30
87 (1) AM
RTL
367
F2: [2356]
89kips
(1)
RSP
139 1095
kips g's/v (1)
A1: [41309]
RMX
177 1115
kips g's/v (1)
A2: [41315]
EMX
16.6 k-ft
ETR
38.3 (%)
STK
7.46 ft
CSX
32.4 ksi
TSX
1.4 ksi
BTA
100.0 (%)
18.1
f/s
V
102.4ms
6.84 ms
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
56.83 ft
F12
173
ft
in^2
ksi
k/ft3
f/s
kse c/ft
56.16 ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsion 2001.086
ISU8
ISU8 6th restrike
HP10x42
P DA OP : KAM
400
kips
th
ISU8-6 Re-strike
F
BN 5
8/11/2009 8:05:51 AM
RTL
384 kips
RSP
138 kips
RMX
208 kips
EMX
18.9 k-ft
ETR
43.8 (%)
STK
7.43 ft
CSX
33.0 ksi
TSX
0.5 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
W S 16807.9
PILE DRIVING ANALYZER
®
22.1
Ve rsion 2001.086EA/C
LP
57.00
6.84 ms
IOWA DOT
ISU9
ISU9 1st bor
PDA OP: KAM
Figure C.2.8. PDA force and velocity HP10x42
records for ISU8
F12
400
kips
ISU9-EOD
F
V
LE
50.50
AR
12.40
102.4ms
EM
30000
SP
0.492
PILE DRIVING ANALYZER
®
W S 16807.9
Ve rsion 2001.086
EA/C
22.1
ISU9 1st bor LP
47.00
IOWA DOT
ISU9
PDA OP: KAM
HP10x42
400
kips
A12
BN 4
F1: [2355] 4:28:36
87 (1) PM
1/18/2010
F2:
[2356]
89 kips
(1)
RTL
245
A1: [41309] 1095 g's/v (1)
RSP
146 kips
A2: [41315] 1115 g's/v (1)
RMX
226 kips
EMX
24.1 k-ft
ETR
56.3 (%)
STK
8.28 ft
CSX
32.5 ksi
TSX
3.0 ksi
BTA
100.0 (%)
18.1
f/s
6.01 ms
st
ISU9-1 Re-strike
F
18.1
f/s
V
102.4ms
6.01 ms
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
F12 A12
BN 5
1/18/2010
4:28:37
PM
F1:
[2355] 87
(1)
RTL[2356]260
kips
F2:
89 (1)
RSP[41309]
177
kipsg's/v (1)
A1:
1095
RMX
217
kipsg's/v (1)
A2: [41315] 1115
EMX
20.3 k-ft
ETR
47.3 (%)
STK
7.39 ft
CSX
30.0 ksi
TSX
0.8 ksi
BTA
100.0 (%)
LE
50.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
47.00 ft
F12
174
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU9
ISU9 2nd bor
HP10x42
P DA OP : KAM
400
kips
ISU9-2nd Re-strike
F
BN 4
1/18/2010 4:38:34 P M
RTL
284 kips
RSP
202 kips
RMX
215 kips
EMX
19.7 k-ft
ETR
45.9 (%)
STK
7.52 ft
CSX
30.6 ksi
TSX
5.7 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
50.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
ISU9 2nd bor LP
47.42
IOWA DOT
6.01 ms
ISU9
P DA OP : KAM
HP10x42
400
kips
ISU9-3rd Re-strike
F
18.1
f/s
V
IOWA DOT
ISU9
P DA OP : KAM
HP10x42
400
kips
F12 A12
BN 4
1/18/2010
4:38:34
PM
F1:
[2355] 87
(1)
RTL [2356]284
kips
F2:
89 (1)
RSP [41309]
202
kipsg's/v (1)
A1:
1095
RMX[41315]
215
kipsg's/v (1)
A2:
1115
EMX
19.7 k-ft
ETR
45.9 (%)
STK
7.52 ft
CSX
30.6 ksi
TSX
5.7 ksi
BTA
100.0 (%)
LE
50.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsion 2001.086
EA/C
22.1
ISU9 4th bor LP
47.42
6.01 ms
th
ISU9-4 Re-strike
F
18.1
f/s
V
102.4ms
6.01 ms
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
F12 A12
BN 4
1/19/2010
8:56:27
F1:
[2355] 87
(1) AM
RTL [2356]305
kips
F2:
89 (1)
RSP
215
kipsg's/v (1)
A1: [41309] 1095
RMX[41315]
227
kipsg's/v (1)
A2:
1115
EMX
21.8 k-ft
ETR
50.9 (%)
STK
8.14 ft
CSX
32.8 ksi
TSX
0.0 ksi
BTA
100.0 (%)
LE
50.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
48.00 ft
F12
175
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
PILE DRIVING ANALYZER ®
Ve rsion 2001.086
ISU9
ISU9 5th bor
HP10x42
PDA OP: KAM
400
kips
ISU9-5th Re-strike
F
BN 5
1/21/2010 1:10:20 PM
RTL
310 kips
RSP
224 kips
RMX
229 kips
EMX
22.2 k-ft
ETR
51.9 (%)
STK
7.66 ft
CSX
32.1 ksi
TSX
0.0 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
50.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086EA/C
22.1
ISU9 6th bor LP
48.08
IOWA DOT
6.01 ms
ISU9
P DA OP : KAM
HP10x42
400
kips
ISU9-6th Re-strike
F
18.1
f/s
V
F12 A12
BN 11
1/28/2010
AM
F1: [2355] 10:55:01
87 (1)
RTL
320
kips
F2: [2356] 89 (1)
RSP
2331095
kips g's/v (1)
A1: [41309]
RMX
233
kips g's/v (1)
A2: [41315] 1115
EMX
21.7 k-ft
ETR
50.6 (%)
STK
8.19 ft
CSX
32.8 ksi
TSX
0.2 ksi
BTA
100.0 (%)
LE
50.50
AR
12.40
102.4ms
EM
30000
SP
0.492
W S 16807.9
PILE DRIVING ANALYZER
®
EA/C
22.1
Ve rsion 2001.086
48.58
ISU10 driving LP
IOWA DOT
6.01 ms
ISU10
PDA OP: KAM
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
HP10x42for ISU9
Figure C.2.9. PDA force and velocity records
F12
400
kips
ISU10-EOD
F
A12
BN 320
F1:
[2355] 87
(1)
3/31/2010
4:49:55
PM
F2:
89 (1)
RTL[2356]213
kips
A1:
1095
RSP[41309]
138
kipsg's/v (1)
A2: [41315] 1115 g's/v (1)
RMX
158 kips
EMX
17.1 k-ft
ETR
39.9 (%)
STK
6.22 ft
CSX
25.6 ksi
TSX
1.2 ksi
BTA
100.0 (%)
18.1
f/s
V
102.4ms
6.84 ms
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
F12
176
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU10
ISU10 1st bor
HP10x42
P DA OP : KAM
400
kips
ISU10-1st Re-strike
F
BN 3
3/31/2010 4:55:22 P M
RTL
220 kips
RSP
138 kips
RMX
160 kips
EMX
18.8 k-ft
ETR
43.9 (%)
STK
6.56 ft
CSX
27.0 ksi
TSX
1.5 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
47.00
ISU10 2nd borLP
IOWA DOT
6.84 ms
ISU10
P DA OP : KAM
HP10x42
400
kips
ISU10-2nd Re-strike
F
18.1
f/s
V
IOWA DOT
ISU10
P DA OP : KAM
HP10x42
400
kips
F12 A12
BN 3
3/31/2010
5:05:50
F1:
[2355] 87
(1) P M
RTL [2356]225
kips
F2:
89 (1)
RSP [41309]
140
kipsg's/v (1)
A1:
1095
RMX[41315]
163
kipsg's/v (1)
A2:
1115
EMX
19.1 k-ft
ETR
44.7 (%)
STK
6.65 ft
C SX
27.7 ksi
TSX
1.5 ksi
BTA
100.0 (%)
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
47.80
ISU10 3rd borLP
6.84 ms
ISU10-3rd Re-strike
F
18.1
f/s
V
102.4ms
6.84 ms
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
F12 A12
BN 3
3/31/2010
5:46:42
PM
F1:
[2355] 87
(1)
F2:
89 (1)
RTL[2356]225
kips
A1:
1095
RSP[41309]
143
kipsg's/v (1)
A2:
1115
RMX[41315]
166
kipsg's/v (1)
EMX
18.3 k-ft
ETR
42.7 (%)
STK
6.55 ft
C SX
27.5 ksi
TSX
1.5 ksi
BTA
100.0 (%)
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
48.50 ft
F12
177
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
IOWA DOT
P ILE DRIVING ANALYZER ®
Ve rsio n 2001.086
ISU10
ISU10 4th bor
HP10x42
P DA O P : KAM
400
kips
ISU10-4th Re-strike
F
BN 4
4/1/2010 9:17:30 AM
RTL
224 kips
RSP
144 kips
RMX
170 kips
EMX
19.6 k-ft
ETR
45.7 (%)
STK
6.44 ft
C SX
27.2 ksi
TSX
1.2 ksi
BTA
100.0 (%)
18.1
f/s
V
LE
57.50
AR
12.40
102.4ms
EM
30000
SP
0.492
P ILE DRIVING ANALYZER
®
W S 16807.9
Ve rsio n 2001.086
EA/C
22.1
ISU10 5th borLP
48.80
IOWA DOT
6.84 ms
ISU10
P DA O P : KAM
HP10x42
400
kips
ISU10-5th Re-strike
F
18.1
f/s
V
102.4ms
6.84 ms
ft
in^2
ksi
k/ft3
f/s
kse c/ft
ft
F12 A12
BN 4
4/5/2010
F1:
[2355]9:11:02
87 (1) AM
RTL[2356]219
kips
F2:
89 (1)
RSP[41309]
138
kipsg's/v (1)
A1:
1095
RMX[41315]
175
kipsg's/v (1)
A2:
1115
EMX
20.7 k-ft
ETR
48.3 (%)
STK
6.64 ft
C SX
27.0 ksi
TSX
1.7 ksi
BTA
89.0 (%)
LE
57.50 ft
AR
12.40 in^2
EM
30000 ksi
SP
0.492 k/ft3
W S 16807.9 f/s
EA/C
22.1 kse c/ft
LP
49.40 ft
Figure C.2.10. PDA force and velocity records for ISU10
F12
A12
F1: [2355] 87 (1)
F2: [2356] 89 (1)
A1: [41309] 1095 g's/v (1)
A2: [41315] 1115 g's/v (1)
178
C.3. Schematic Drawing and Configuration of the Vertical Static Load Tests
Figure C.3.1. Configuration of four anchor piles and a steel test pile for ISU1 at Mahaska
County
Figure C.3.2. Configuration of two anchor piles and a steel test pile for ISU2 at Mills
County
Figure C.3.3. Configuration of two anchor piles and a steel test pile for ISU3 at Polk
County
179
Figure C.3.4. Configuration of two anchor piles and a steel test pile for ISU4 at Jasper
County
Figure C.3.5. Configuration of two anchor piles and two steel test piles for ISU6 and ISU7
at Buchanan County
Figure C.3.6. Configuration of two anchor piles and a steel test pile for ISU8 at Poweshiek
County
180
Figure C.3.7. Configuration of two anchor piles and a steel test pile for ISU9 at Des Moines
County
Figure C.3.8. Configuration of two anchor piles and a steel test pile for ISU10 at Cedar
County
181
Figure C.3.9. Schematic drawing of vertical static load test for ISU1 at Mahaska County
182
Figure C.3.10. Schematic drawing of vertical static load test for ISU2 at Mills County
183
Steel Angle
3
(L 2 x 2 x 16
)
Steel Angle
3
(L 2 x 2 x 16
)
Figure C.3.11. Schematic drawing of vertical static load test for ISU3 at Polk County
184
Steel Angle
3
(L 2 x 2 x 16
)
Steel Angle
3
(L 2 x 2 x 16
)
Figure C.3.12. Schematic drawing of vertical static load test for ISU4 at Jasper County
185
Steel Angle
3
(L 2 x 2 x 16
)
Steel Angle
3
(L 2 x 2 x 16
)
Steel Angle
3
(L 2 x 2 x 16
)
Steel Angle
3
(L 2 x 2 x 16
)
Figure C.3.13. Schematic drawing of vertical static load tests for ISU6 and ISU7 at Buchanan County
186
Steel Angle
3
(L 2 x 2 x 16
)
Steel Angle
3
(L 2 x 2 x 16
)
Figure C.3.14. Schematic drawing of vertical static load test for ISU8 at Poweshiek County
187
Steel Angle
3
(L 2 x 2 x 16
)
Steel Angle
3
(L 2 x 2 x 16
)
Figure C.3. 15. Schematic drawing of vertical static load tests for ISU9 and ISU10 at Des Moines County and Cedar County
respectively
188
C.4. Static Load Test Load and Displacement
Load , Q (kip)
0
50
100
150
200
250
0.0
Pile Resistance
212 kips
(Smooth Curve)
0.1
Displacement , ∆ (in)
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Figure C.4.1. A load-displacement curve and Davisson’s criteria for ISU1 at Mahaska
County
0
20
40
Load, Q (kips)
60
80
100
120
140
0.00
Pile Resistance
125 kips
0.20
Displacement, ∆ (in)
0.40
0.60
0.80
1.00
1.20
1.40
Figure C.4.2. A load-displacement curve and Davisson’s criteria for ISU2 at Mills County
189
0
20
40
60
Load, Q (kips)
80
100
120
0.00
140
160
Pile Resistance
150 kips
0.10
Displacement, ∆ (in)
0.20
0.30
0.40
0.50
0.60
0.70
0.80
Figure C.4.3. A load-displacement curve and Davisson’s criteria for ISU3 at Polk County
Load, Q (kips)
0
20
40
60
80
100
120
140
160
180
0.00
Pile Resistance
154 kips
0.20
Displacement, ∆ (in)
0.40
0.60
0.80
1.00
1.20
Figure C.4.4. A load-displacement curve and Davisson’s criteria for ISU4 at Jasper County
190
0
20
40
60
80
Load , Q (kips)
100
120
140
160
180
200
220
240
0.00
Pile Resistance
213 kips
0.10
Settlement (inches)
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
Figure C.4.5. A load-displacement curve and Davisson’s criteria for ISU6 at Buchanan
County
0
10
20
Load, Q (kips)
30
40
0.00
50
60
70
Pile Resistance
53 kips
0.05
Displacement, ∆ (in)
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
Figure C.4.6. A load-displacement curve and Davisson’s criteria for ISU7 at Buchanan
County
191
0
20
40
Load, Q (kips)
80
100
120
60
0.00
140
160
180
200
Pile Resistance
162 kips
0.10
Displacement, ∆ (in)
0.20
0.30
0.40
0.50
0.60
0.70
0.80
Figure C.4.7. A load-displacement curve and Davisson’s criteria for ISU8 at Poweshiek
County
0
20
40
60
80
Load, Q (kips)
100
120
140
160
180
200
220
0.00
Pile Resistance
158 kips
0.10
Displacement, ∆ (in)
0.20
0.30
0.40
0.50
0.60
0.70
0.80
Figure C.4.8. A load-displacement curve and Davisson’s criteria for ISU9 at Des Moines
County
192
0
20
40
60
Load, Q (kip)
80
100
120
140
160
180
0.0
Pile Resistance
127 kips
Displacement, ∆ (in)
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Figure C.4.9. A load-displacement curve and Davisson’s criteria for ISU10 at Cedar
County
193
APPENDIX D: DATA INTERPRETATION AND ANALYSIS
D.1. Static Load Test Pile Force Transferred Profiles
0
20
40
Pile Force Distribution (kip)
60
80
100
120
0
140
Q=5.5 kips
Clay
Q=11.9 kips
Q=17.43 kips
GWT
10
Q=23.3 kips
Q=29.9 kips
Depth Below Ground (ft)
Q=35.3 kips
Clayey Silt to
Silty Clay
20
Q=41.2 kips
Q=47.0 kips
Q=53.6 kips
Q=59.2 kips
Silty Clay to Clay
Q=64.9 kips
Q=70.8 kips
30
Q=77.0 kips
Q=82.8 kips
Q=88.3 kips
Clay
40
Q=91.4 kips
Q=96.8 kips
Q=100.8 kips
50
Clayey Silt to
Silty Clay
Q=106.8 kips
Q=112.1 kips
Q=118.0 kips
Q=126.8 kips
Qm=125 kips
60
Figure D.1.1. Pile force distribution along the embedded pile length of the test pile ISU2
194
0
20
40
Pile Force Distribution (kip)
60
80
100
120
140
0
Q=8.2 kips
Clay
5
Q=15.4 kips
Q=23.2 kips
Q=30.9 kips
10
Q=38.4 kips
Depth Below Ground (ft)
15
GWT
Q=46.6 kips
Q=53.8 kips
20
Q=61.6 kips
Clayey Silt
to Silty Clay
25
Q=69.3 kips
Q=78.5 kips
Q=86.7 kips
30
Q=94.3 kips
Q=100.8 kips
35
Sandy Silt
to Clayey Silt
40
Q=110.6 kips
Q=134.3 kips
Clayey Silt
to Silty Clay
45
Q=142.5 kips
Q=149.5 kips
Clay
Qm=150 kips
50
Figure D.1.2. Pile force distribution along the embedded pile length of the test pile ISU3
195
Pile Force Distribution (kip)
0
20
40
60
80
100
0
140
160
180
Silty Clay to Clay
Silty Sand to
Sandy Silt
Sensitive Fine
Grained
GWT
Sandy Silt to
Clayey Silt
10
Depth Below Ground (ft)
120
20
Silty Sand to
Sandy Silt
Q=11.8 kips
Q=19.0 kips
Q=29.0 kips
Q=38.8 kips
Q=48.7 kips
Q=58.5 kips
Q=68.5 kips
Q=78.9 kips
Q=88.3 kips
30
Clay
Q=98.1 kips
Q=107.5 kips
Silty Clay to Clay
40
Q=116.0 kips
Q=127.3 kips
Q=136.6 kips
Clayey Silt to Silty Clay
Q=145.9 kips
50
Q=153.8 kips
Q=155.9 kips
Qm=154 kips
60
Figure D.1.3. Pile force distribution along the embedded pile length of the test pile ISU4
196
Pile Force Distribution (kip)
0
20
40
60
80
100 120 140 160 180 200 220 240 260
0
Q=0.2 kip
Q=11.6 kips
Clay
10
Q=19.8 kips
Q=29.0 kips
GWT
Sand to
Silty Sand
20
Q=39.7 kips
Q=49.6 kips
Q=60.1 kips
Depth Below Ground (ft)
Q=70.4 kips
Clay
Q=80.0 kips
Q=89.4 kips
30
Silty Sand to Sandy Silt
Silty Clay to Clay
Q=99.2 kips
Q=108.6 kips
Q=117.8 kips
Q=128.7 kips
40
Q=139 kips
Q=148.9 kips
50
Clayey Silt to Silty Clay
Q=158.4 kips
Q=167.9 kips
Q=178.2 kips
Q=186.2 kips
Q=197 kips
60
Q=203.7 kips
Q=210.9 kips
70
Note: The percent pile load at toe was assumed from CAPWAP analysis
Qm=213 kips
Figure D.1.4. Pile force distribution along the embedded pile length of the test pile ISU6
197
0
20
40
Pile Force Distribution (kip)
60
80
100
120
140
160
0
Q=5.57 kips
Q=20.4 kips
Clay
Q=30.2 kips
10
Q=40.2 kips
Depth Below Ground (ft)
Q=50.1 kips
Silty Clay
to Clay
20
Q=59.6 kips
Q=70.2 kips
GWT
Silty Sand to
Sandy Silt
30
Sand
Clayey Silt to Silty Clay
40
Q=79.9 kips
Q=89.4 kips
Q=99.9 kips
Q=109.8 kips
Q=119.8 kips
Q=129.1 kips
Silty Sand to
Sandy Silt
Q=138.5 kips
Q=148.2 kips
50
Clayey Silt to Silty Clay
Silty Clay to Clay
Q=157.3 kips
Q=164.2 kips
Qm=162 kips
60
Figure D.1.5. Pile force distribution along the embedded pile length of the test pile ISU8
198
0
20
40
Pile Force Distribution (kip)
60
80
100
120
140
160
0
180
200
Sandy Silt to
Clayey Silt
Q=10 kips
Q=19 kips
Q=30 kips
10
Clay
Q=39 kips
Q=49 kips
Depth Below Ground (ft)
GWT
20
Q=59 kips
Q=69 kips
Q=79 kips
Q=88 kips
30
Q=98 kips
Sand
Q=109 kips
Q=117 kips
40
Q=127 kips
Q=136 kips
Q=145 kips
50
Q=152 kips
Q=161 kips
Q=170 kips
60
Figure D.1.6. Pile force distribution along the embedded pile length of the test pile ISU9
199
D.2. Shaft Resistance Distribution
Shaft Resistance Distribution (kip)
0
20
40
0
Depth Below Ground (ft)
EOD
BOR2
SLT
Clay (CL)
GWT
10
60
BOR1
BOR3
Silty Clay to Silty Clay (CL)
20
30
Silty Clay to Clay (CL)
40
Clay (CL)
50
Silty Clay to Silty Clay (CL)
60
0
2
4
6
8
10
12
14
16
18
20
Uncorrected SPT N-value
Figure D.2.1. SLT measured and CAPWAP estimated pile shaft resistance distributions for
test pile ISU2
Shaft Resistance Distribution (kip)
0
20
40
60
0
Clay
Depth Below Ground (ft)
10
GWT
Silty Clay to Silty Clay
20
EOD
BOR2
BOR4
30
BOR1
BOR3
BOR5
Sandy Silt to Clayey Silt
40
Clayey Silt to Silty Clay
50
Clay
60
Clayey Silt to Silty Clay
0
2
4
6
8
10
12
14
16
18
20
22
24
Uncorrected SPT N-value
Figure D.2.2. SLT measured and CAPWAP estimated pile shaft resistance distributions for
test pile ISU3
200
Shaft Resistance Distribution (kip)
0
20
40
60
0
Silty Clay to Clay
Silty Sand to Sandy Silt
10
Sensitive fine Grained
Depth Below Ground (ft)
GWT
Sandy Silt to Clayey Silt
20
Silty Sand to Sandy Silt
30
Clay
Silty Clay to Clay
40
Clayey Silt to Silty Clay
50
EOD
BOR2
BOR4
BOR6
60
0
2
4
6
8
10
12
BOR1
BOR3
BOR5
SLT
14
16
18
Uncorrected SPT N-value
Figure D.2.3. SLT measured and CAPWAP estimated pile shaft resistance distributions for
test pile ISU4
Shaft Resistance Distribution (kip)
0
20
40
0
EOD
BOR3
BOR6
Clay
10
60
BOR1
BOR4
BOR7
BOR2
BOR5
BOR8
Depth Below Ground (ft)
GWT
Sand to silty Sand
20
Clay
30
Silty Sand to Sandy Silt
Silty Clay to Clay
40
50
Clayey Silt to Silty Clay
60
0
2
4
6
8
10 12 14 16 18 20
Uncorrected SPT N-value
22
24
26
28
30
Figure D.2.4. CAPWAP estimated pile shaft resistance distributions for test pile ISU6
201
Shaft Resistance Distribution (kip)
0
5
10
15
20
25
30
0
10 ft Prebore
Depth Below Ground (ft)
5
EOD
BOR2
BOR4
Clay
BOR1
BOR3
BOR5
10
GWT
15
Sand to silty Sand
20
25
Clay
30
Silty Sand to Sandy Silt
Silty Clay to Clay
35
40
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
Uncorrected SPT N-value
Figure D.2.5. CAPWAP estimated pile shaft resistance distributions for test pile ISU7
Shaft Resistance Distribution (kip)
0
20
40
60
0
EOD
BOR2
BOR4
BOR6
Clay
Depth Below Ground (ft)
10
BOR1
BOR3
BOR5
SLT
Silty Clay to Clay
20
GWT
Silty Sand to Sandy Silt
30
Sand
40
Clayey Silt to Silty Clay
Silty Sand to Sandy Silt
50
Clayey Silt to Silty Clay
Silty Clay to Clay
60
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
Uncorrected SPT N-value
Figure D.2.6. SLT measured and CAPWAP estimated pile shaft resistance distributions for
test pile ISU8
202
Shaft Resistance Distribution (kip)
0
20
40
60
0
Sandy Silt to Clayey Silt
Clay
Depth Below Ground (ft)
10
GWT
20
EOD
BOR2
BOR4
BOR1
BOR3
BOR5
30
Sand
40
50
60
0
2
4
6
8 10 12 14 16 18 20 22 24 26 28 30 32 34
Uncorrected SPT N-value
Figure D.2.7. SLT measured and CAPWAP estimated pile shaft resistance distributions for
test pile ISU9
Shaft Resistance Distribution (kip)
0
20
0
40
60
Sandy Silt to Clayey Silt
GWT
Sand to Silty Sand
Sandy Silt to Clayey Silt
10
Depth Below Ground (ft)
Sand
20
30
40
EOD
BOR1
50
BOR2
BOR3
BOR4
60
BOR5
0
10
20
30
40
50
60
70
80
Uncorrected SPT N-value
Figure D.2.8. CAPWAP estimated pile shaft resistance distributions for test pile ISU10
203
D.3. Pile Driving Resistance
SPT N-value
0
0
0
5
10
15
0
0
Blow/ft
Blow/ft
SPT N-value
Clay
2
Clay
5
Clay
15
Silty Sand to Sand
6
20
Sandy silt to clayey Silt
Silty Clay to Silty Clay
6
Silty Clay to Clay
30
10
35
12
40
Clay
45
Silty Clay to Silty Clay
Sand to Silty Sand
50
16
EOD
BOR1
30
55
BOR2
18
Clayey silt to Silty Clay
10
10
20
30
40
50
65
20
0
60
Hammer Blows per ft
BOR3
60
EOD
35
0
20
25
8
14
25
8
15
Pile Penetration Below Ground (ft)
10
Pile Penetration Below Ground (m)
GWT
4
10
4
Pile Penetration Below Ground (ft)
Pile Penetration Below Ground (m)
GWT
Sensitive Fine Grained
2
5
5
10
15
20
Hammer Blow per ft
ISU1 (Mixed Profile)
ISU2 (Clay Profile)
Figure D.3.1. Pile driving resistances for ISU1 and ISU2 in terms of hammer blow count
204
SPT N-value
5
10
15
20
0
0
0
Blow/ft
SPT N-value
Clay
2
5
5
Sensitive fine Grained
4
25
8
30
10
35
Sandy Silt to
Clayey Silt
12
40
Clayey Silt to Silty Clay
45
14
Pile Penetration Below Ground (ft)
Pile Penetration Below Ground (m)
Pile Penetration Below Ground (m)
Silty Clay to Silty Clay
BOR1/2/3
Clay
EOD
GWT
Sandy Silt to Clayey Silt
6
Silty Sand to Sandy Silt
16
35
12
Silty Clay to Clay
Clayey Silt to Silty Clay
14
BOR1
0
5
10
15
BOR6
65
0
Hammer Blow per ft
55
60
20
20
45
BOR5
18
65
20
BOR4
BOR2
40
50
BOR3
EOD
60
20
10
16
Clayey Silt to Silty Clay
15
30
Clay
55
18
10
25
8
50
BOR4
BOR5
5
Silty Clay to Clay
Silty Sand to Sandy Silt
15
20
20
0
2
4
6
15
Blow/ft
SPT N-value
10
GWT
10
0
Pile Penetration Below Ground (ft)
0
SPT N-value
5
10
15
20
25
Hammer Blow per ft
ISU3 (Clay Profile)
ISU4 (Clay Profile)
Figure D.3.2. Pile driving resistances for ISU3 and ISU4 in terms of hammer blow count
205
SPT N-value
0
5
10
15
SPT N-value
20
0
25
0
0
0
Blow/ft
SPT N-value
2
10
20
25
0
Note: Top 10 ft was predrilled
Blow/ft
SPT N-value
Clay
4
15
5
Clay
10
GWT
5
2
15
10
20
Clay
25
8
30
Silty Sand to Sandy Silt
10
35
Silty Clay to Clay
12
40
Clayey Silt to Silty Clay
45
14
BOR1
4
GWT
Sand to silty Sand
6
20
8
EOD
BOR1
50
BOR5
EOD
18
BOR4
BOR6
10
55
BOR7
10
20
30
40
50
BOR6
BOR5
65
20
60
35
BOR7
Clayey Silt to Silty Clay
12
70
30
BOR4
BOR3
60
BOR2
0
Silty Sand to Sandy Silt
BOR2
Silty Clay to Clay
BOR8
25
Clay
BOR3
16
15
0
2
Pile Penetration Below Ground (ft)
6
Pile Penetration Below Ground (m)
Sand to silty Sand
Pile Penetration Below Ground (ft)
Pile Penetration Below Ground (m)
5
4
6
40
8
10
Hammer Blow per ft
Hammer Blow per ft
ISU6 (Clay Profile)
ISU7 (Mixed Profile)
Figure D.3.3. Pile driving resistances for ISU6 and ISU7 in terms of hammer blow count
206
SPT N-value
0
20
40
60
80
0
0
GWT
Sandy Silt to Clayey Silt
5
Sandy to Silty Sand
Sandy to Clayey Silt
2
10
4
15
6
20
25
8
30
10
35
12
40
14
BOR4
BOR2
BOR3
16
45
EOD
BOR1
Pile Penetration Below Ground (ft)
Pile Penetration Below Ground (m)
Sand
50
BOR5
55
18
60
Blow/ft
SPT N-value
65
20
0
5
10
15
20
Hammer Blow per ft
Figure D.3.4. Pile driving resistance for ISU10 (sand profile) in terms of hammer blow
count
207
D.4. Relationship between Soil Properties and Pile Shaft Resistance Gain
-20
-10
Shaft Resistance Gain Distribution (kip)
10
20
30
40
0
0
ISU2
Depth Below Ground (ft)
60
Shaft Gain (CAPWAP-3 days)
Shaft Gain (SLT-9 days)
SPT N-value
Plasticity Index
in2/min
Cv=0.023
OCR=1.0; Cc=0.193
10
50
Cv=0.008 in2/min
OCR=1.14; Cc=0.208
20
Cv=0.020 in2/min
OCR=1.05; Cc=0.293
Ch=0.138 in2/min
30
40
50
Cv=0.018 in2/min
OCR=1.0; Cc=0.273
60
0
2
4
6
8
10
12
14
16
18
20
22
SPT N-value or Plasticity Index
24
26
28
30
Figure D.4.1. Relationship between soil properties and shaft resistance gain for ISU2
Shaft Resistance Gain Distribution (kip)
-20
-10
0
10
20
30
0
40
50
60
Cv=0.011 in2/min
OCR=4.70; Cc=0.125
ISU3
Depth Below Ground (ft)
10
20
Ch=0.029 in2/min
Cv=0.012 in2/min; OCR=1.52; Cc=0.171
30
Series3
Shaft Gain (CAPWAP-2 days)
SPT N-value
Plasticity Index
40
Cv=0.006 in2/min
OCR=1.30; Cc=0.221
50
60
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
SPT N-value or Plasticity Index (%)
Figure D.4.2. Relationship between soil properties and shaft resistance gain for ISU3
208
Shaft Resistance Gain Distribution (kip)
-20
-10
0
10
0
30
40
50
60
Shaft Gain (SLT-16 days)
Series1
SPT N-value
Plasticity Index
2
Cv=0.019 in /min; OCR=2.48; Cc=0.174
ISU4
10
Depth Below Ground (ft)
20
Ch=0.0056 in2/min
Ch=0.003 in2/min
20
Cv=0.012 in2/min; OCR=1.63; Cc=0.127
30
40
Ch=0.0014 in2/min
50
Cv=0.012 in2/min; OCR=1; Cc=0.129
Ch=0.0038 in2/min
60
Cv=0.007 in2/min; OCR=1.03; Cc=0.124
0
2
4
6
8
10 12 14 16 18 20 22 24
SPT N-value or Plasticity Index (%)
26
28
30
Figure D.4.3. Relationship between soil properties and shaft resistance gain for ISU4
Shaft Resistance Gain Distribution (kip)
-20
-10
0
10
20
30
40
50
60
0
ISU6
Cv=0.005 in2/min
OCR=1.2; Cc=0.3
Depth Below Ground (ft)
10
20
Series1
SPT N-value
Plasticity Index
30
40
50
Ch=0.0012 in2/min
Cv=0.006 in2/min
OCR=1.09; Cc=0.211
Cv=0.009 in2/min
OCR=1; Cc=0.092
60
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
SPT N-value or Plasticity Index (%)
Figure D.4.4. Relationship between soil properties and shaft resistance gain for ISU6
209
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