Helical Pile

Helical Piles

The helical pile system is a segmented deep foundation system with helical bearing plates welded to a central shaft. Load is transferred from the shaft to the soil through helical bearing plates. As a result of their true helical shape, the helices do not auger into the soil, but instead screw into it with minimal disturbance.

The first section, known as the lead section, contains the helical plates. The lead section can consist of one to four helices. If required, additional helices can be added with the use of helical extensions.

Plain extensions are then added until the lead section penetrates the bearing strata and the necessary torque is achieved. The true helix geometry of each steel bearing plate discourages soil disturbance during installation.

For new deep foundations, helical piles are installed at intervals between the footing forms and tied into the rebar grid work prior to pouring concrete. The piles are extended to depths attaining the installing torque that correlates with the required load bearing capacity.

The helical pile foundation is preferred over driven piles, drilled shafts, grouted tendons, auger-cast piles, belled piers and other deep foundation systems for a number of compelling reasons:

  • Quick installation and immediate loading
  • Pre-Engineered
  • Eliminates high-mobilization costs associated with driven piles, drilled shafts or auger cast piles
  • Instant torque-to-capacity feedback for production control
  • Easily modified in the field
  • No need for concrete to cure
  • Uses common construction equipment that is easily fitted with hydraulically-driven torque motors
  • Easy to use in limited access sites, high water tables and weak surface soils

To date, the A.B. CHANCE systems are the only company with a pre-engineered and manufactured underpinning system that has been evaluated and listed by all national building code agencies.