Preconstruction Auger Piers

Before construction begins on questionable soils, RAB Geotechnical Construction Specialist offers alternative solutions to compaction grouting. Auger piers can be installed in a grid pattern under the foundation slab area, typically 6’– 8’ spacing. The auger pier’s flyted shaft allows the pier to drill through all types of soil layers to reach load bearing strata or limerock. Specialized “Flat” brackets are available so the foundation can me poured over the bracket so it’s embedded in the slab. As an alternative connector, Re-bar can be welded to the interior of the underpin pipe and bent at an angle so the slab can be poured over it. This process allows the structure to basically stand on steel stilts to withstand soil movements or collapses.

Preconstruction Helical Pier

The Helical pier can be used for a variety of applications. Preconstruction projects with questionable soils are a perfect application. Like the Auger Pier, the Helical Pier is installed in a grid pattern of 6’-8-10’ spacing. The difference between the Auger Pier and the Helical Pier is that the Helical Pier torques out in dense soils so the driller does not have to reach limestone. This can save the contractor money since the deeper the pier, the more it cost. Typical depths of Helical piers are 20’ -25’ depending on the soil density.