Preserve the value of your new home or building

Helical anchors installed prior to construction prevent downward settlement before it starts. By monitoring hydraulic pressures, anchors are load tested as they are installed.

Excerpted from Professional Engineer:
The Magazine of North Carolina Engineering, December 2003

How many times on a new construction site have you heard, “We’ve got a problem”? In the pre-construction stages, this might very well mean that in digging down to the expected subgrade elevation for the foundation, the contractors have discovered that the soil is too soft to place the footings. Poor soil conditions are particularly common in the Triassic basins found throughout North Carolina.

Despite more than 20 years’ solid presence in the industry, piering is not well known in the building community, which is why it is often not used, even when conditions might suggest it is the best option.

The piers pass through the poor soil strata including expansive soils that are affected by changes in moisture content, organic material that will decay with time, and loose or soft soils (either natural or man made fills) that would settle under the weight of the structure — all of which potentially lead to foundation problems — and support the structure on deeper, more stable soils that can provide adequate support to the structure.

Rick Sykes, owner of Ram Jack NC in Durham, says, “The biggest advantage is that helical anchors installed prior to construction prevent downward settlement before it starts. By monitoring hydraulic pressures, anchors are load tested as they are installed. It’s foundation repair done right at the start.”

Given the opportunity, Sykes tells builders, “Before the footings for the foundation go in, contact an engineer to have your soil tested for load-bearing capacity and expansive clay content. Steel reinforcing bars and larger, deeper footings may prevent settlement from occurring. Often, installing new construction piers prior to pouring the concrete footings is the answer.

Admay concurs, saying, “To install a helical pier properly, a soil test should be performed by a geotechnical engineer to determine how deep the pier must be installed to bear in a strata with adequate strength to support the structure. The engineer determines the layout of the pier and the reinforcing required in the footings and slabs. The piers should be laid out by a surveyor before a specialized crew comes in to install the piers.”

Helical piers are turned into the ground much like a corkscrew. Each pier has one or more “flights,” which are like blades that draw down the pier and anchor it into the ground. Sykes states, “Not all piering is the same. You need to consider the best quality equipment, as well as long-term issues such as warranty. Ram Jack provides a transferable life-of-structure warranty on our helical piering, and while we are locally owned, we are backed by the equipment and expertise of a more than 30-year-old national leader in the foundation construction and repair industry. With Ram Jack’s patented helical piering system, soft soil below 4 to 5 feet becomes moot.”

Helical piers are screwed into the ground and held in place with their flights, so they support more than just downward pressure — they can also resist uplift forces. In other words, they can be used as tiebacks for retaining walls and bulkheads, or uplift anchors for signs and other light structures. Also, builders can use helical piers as tiebacks in conjunction with vertical piers on hillside lots to resist both settlement and lateral movement.

This system successfully supports structures in virtually all soil conditions, and it can be used for stabilizing foundations and slabs built on questionable soil, as well as seismic protection, tieback anchoring, deadman anchoring and fixture anchoring. It is especially useful for installation in tight areas. With much less extensive excavation required, helical anchors extend to stable strata under expansive surface soils without significant disturbance of the area around the anchor.