A helical anchor/pile is a deep foundation system with helical screw like bearing plates on a steel shaft. Any structural load is delivered through the pile shaft and to the soil through these bearing plates. The steel shafts are available in either a solid square shaft series or a round pipe shaft series. The solid square shaft piles are available in 1-1/4″ to 2-1/4″ square sizes. The round pipe shaft series are available in 2-7/8″ to 4-1/2″ diameter sizes. Combinations piles of made of both shaft types are also available for compression applications where dense/hard soils must be penetrated but there is a softer/loose soil above the dense bearing strata.
Segments or sections of the piles are bolted together with sleeved couplings. Installation depth is limited by soil density and of course economics. The helical bearing plates only consist of one 360 degree rotation of a screw thread. All helices have a standard 3″ pitch. These precisely manufactured helices do not auger but instead screw into the soil with minimal disturbance. When multiple helical bearing plates are used on a single pile, they are spaced at a distance in which they function independently. Being designed in this manner, the capacity of the pile can be calculated as the sum of all helical plate capacities.
We use only A.B. Chance piles made in the USA