Helical piles. Helical piles, also known as helical piers, are deep foundation underpinning elements constructed using steel shafts with helical flights. The shafts are advanced to bearing depth by twisting them into the soil while monitoring torque to estimate the pile capacity. A thorough understanding of the subsurface conditions is necessary to properly interpret the torque conversion. After reaching design capacity, the tops of the shafts are bracketed to the structure's footing. The finish