CONDITIONS and USES. Bosch 11335K - 35 lb. Demolition Breaker Hammer

CONDITIONS AND USES

Normal Soil Conditions

Diamond Pier foundations sold through retail outlets are designed for projects that are founded in normal sound soils. Normal soils are typical in most residential neighborhoods throughout the United States and are defined in the International Residential Code (IRC) Table R401.4.1. Presumptive Load-Bearing

Values of Foundation Materials.

For residential applications the two most common prescriptive bearing soil types relied upon in the IRC table, and in most local codes, are 2000 psf sands/gravels and 1500 psf silts/clays. Diamond Pier foundations sold through retail outlets must be founded in soils with a minimum 1500 psf bearing strength. Supporting soils that do not meet the presumptive bearing strength defined in the applicable code for your area will not provide expected foundation capacity, and their bearing capacity may need to be determined by a soils investigation. Ask your local code official for soil information regarding your site. Additional soils information may also be available at the U.S. Geological Soils Survey website managed by the U.S. Department of Agriculture—see http://websoilsurvey.sc.egov.usda.gov/.

Supporting Soils

Some soils may not be appropriate for supporting Diamond Pier foundations. Some examples include soils that are weaker than 1500 psf, soils that are highly expansive, shifting or sliding soils, soils on slopes greater than 2:1 (27 degrees), contaminated soils, or soils where traditional concrete piers, accepted by local codes, are unable to provide adequate bearing to support the loads of the project or to protect the structure from the negative effects of frost heave. Where unsound soils exist, a registered design professional may be required to review the project.

Soils can also be weakened when they retain standing water or are improperly drained, and in certain types of soil this can also cause heave problems. A site depression with standing water or the potential for water to pond, pool, or saturate the soil may be an indication that the soil is not sound. Downspouts that discharge at or near a foundation may also cause soil problems, and setting the Diamond Pier foundation system adjacent to or near drainage ditches, creeks, or ponds should be considered carefully. Soils adjacent to existing foundations may also have been improperly or loosely backfilled, which may cause poor drainage or poor soil conditions. Check your local code for drainage requirements in and around foundations. .

Please contact PFI if you have any questions regarding your project or soil conditions, and/or the proper

use of the Diamond Pier product or "Residential Diamond Pier Load Chart," provided in Table 1.

WARNING: You must check for underground utilities and follow the instructions described

under the “Locate Buried Utilities” subsection (page 8) before Diamond Pier

foundations can be installed.

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Residential Diamond Pier Load Chart

Table 1. Residential Diamond Pier Load Chart

Equivalency to a traditional concrete pier is indicated by Base Area Comparison and Frost Zone Rating.

DP-50 ESR-1895 Code Compliant

Model & Pin Length > DP-50 36” DP-50 42” DP-50 50” DP-75 50” DP-75 63”

Bearing in 2000 psf Sands/Gravels

1

3600# 3600# 3600# 5150# 5850#

Bearing in 1500 psf Silts/Clays

1

2700# 2700# 2700# 3870# 4400#

Equivalent Bearing Area 1.8 sf 1.8 sf 1.8 sf 2.58 sf 2.93 sf

Base Area Comparison

Uplift

Lateral

18” cylinder 18” cylinder 18” cylinder 21” cylinder 23” cylinder

670# 920# 1175# 1215# 1380#

575# 820# 1070# 1150# 1310#

Frost Zone Rating

Notes:

12"–24” 30"–42” 48” 48” 60”

1. Values applicable in properly drained, sound soils with a minimum 1500 psf bearing capacity. See

IRC Table R401.4.1 for complete bearing soils listing and Table notes.

2. For simple structures only. No asymmetrical, rotational, overturning, or dynamic loads.

3. All capacities use four pins of the specified length per foundation. Length includes that portion embedded within the foundation head.

4. DP-50 uses defined in paragraph 2.0 of ESR-1895 and per blue-bordered box above are limited to residential decks, covered decks, stairways, and walkways. For DP-50 uses beyond these types of projects, and for DP-75 applications, refer to Cross Pin Group Foundation Load Test

Report (EEI Report No. 07-020-8). See Note 1 for applicable soils.

5. 50” Pins are recommended for use with the DP-50 where uplift and/or lateral loads may govern.

The DP-50 comes with a 1/2” diameter embedded galvanized anchor bolt. The DP-75 comes with a 5/8” diameter embedded galvanized anchor bolt.

6. The Diamond Pier system is a shallow bearing technology that does not require “refusal” or

“friction” resistance, or the professional installation monitoring or special inspection typically associated with conventional vertical or battered piling.

7. Larger Diamond Pier models are available—DP-100E and DP-200E. For these larger pier sizes, site-specific soils information and foundation loads must be determined by a registered design professional and provided to PFI for calculated foundation capacities.

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Diamond Pier foundations provide equal or better performance to traditional concrete foundations

claimed as equivalent. In the "Residential Diamond Pier Load Chart" (Table 1), a “base area

comparison” and “frost zone rating” are defined. These two ratings define the size of the traditional concrete pier foundation that a given Diamond Pier foundation is equivalent to in bearing capacity and frost heave resistance. For example, a DP-50 with 50" bearing pins shows a base area comparison of

18” and a frost zone rating of 48”. This compares with a traditional 18” round, 48” deep poured concrete foundation.

To determine whether the Diamond Pier system can be used for a specific project, a registered design

professional may review the Residential Diamond Pier Load Chart and supporting documentation, and

specify the use of the systems with site-specific requirements or caveats in a submittal to your local code official. Alternatively, PFI may provide a stamped capacity sheet for the Diamond Pier model and pin length appropriate to the job when site-specific soils and loading information is provided. Contact PFI for these specific requirements as well as the typical time frame and fees for this type of review.

Frost Heave

Frost is not an unusual or unsound soil condition unless the site has a history of locally accepted conventional foundations failing due to frost heave or freeze/thaw cycling. In frost zones, a properly drained, sound soil will freeze solid and hold its foundations tight. In heaving areas, water sources, the rate of temperature drop, and certain soil grain sizes can combine to cause pressures on foundations in all directions. The most important of these three factors is the presence of water in the soil, and this makes proper drainage a must—for all types of foundations.

Heave Resistance

Most traditional concrete foundations in frost zones rely on depth and gross weight as protections against frost heave. They use significant volumes of site-poured concrete, which has the potential for many field condition variables and inconsistent mix designs, and their installation requires considerable excavation, which weakens the existing soil structure, invites water problems, and leaves substantial amounts of soil to be removed from a site.

Rather than reaching a specific vertical depth or gross weight, Diamond Pier systems resist heave pressures with their wide-spreading pin pile groups. Embedded in the intact soil structure, the pins are prevented from changing angle under load by the concrete head, creating a stable foundation for both bearing and uplift forces. Because of the unique design of the Diamond Pier head, the pins are also free to move along their axes without compromising the position of the pier or its lock on the pin cluster. This feature allows the Diamond Pier foundation to absorb soil strains caused by frost heave or expansive conditions without losing alignment or transferring these strains to the supported structure.

When assessing projects in extreme frost areas, be aware of sites where traditional concrete footings—

48” to 60” deep—have failed to resist frost heave, requiring larger, deeper concrete piers. Project sites that require concrete footings deeper than 60” to resist frost heave exceed the definition of normal soil

conditions and the limits of the "Residential Diamond Pier Load Chart."

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