Commercial Services

Foundation Settlement » Helical Piers

A helical pier is constructed of a steel central shaft with end bent plates (helixes) at the bottom of the pile. The pile sizes differ by various shaft and combination of shafts of high-strength solid steel bar from 1 ½" to 2 ½" thick to tubular with diameters from 2 7/8" to 12" diameters with various steel thicknesses.

The piles are advanced into the soils by screwing them in with hydraulic gear motors and are bolted and connected in shaft lengths from 3 to 20 ft. (3-10 ft. most common) to extend the depth of the pile. Capacity can be measured during installation, and there is a direct relationship between torque (force required to cause rotation) and capacity. The stiffer the soil the more drive force by way of torque is required, measuring the end bearing capacity of the soil and the pile. Loads are transfeedr from the foundation to the pier shaft to end bearing strata.