Bosch 11335K - 35 lb. Demolition Breaker Hammer Installation Manual download pdf (Page 7)

Diamond Pier

Installation Manual 7

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."

1 2 3 4 5 6 7 8 9 10 11 12 ... 17 18

No comments

Bosch 11335K - 35 lb. Demolition Breaker Hammer Installation Manual Page 7