The Helical Pulldown® Micropile is a method used to form a grout column around the shaft of a standard helical anchor/pile. The installation process can employ grout only (see Figure 2) or grout in combination with either steel or PVC casing (see Figure 3).

To begin the process, a helical anchor/pile is placed into the soil by applying torque to the shaft. The helical shape of the bearing plates creates a significant downward force that keeps the foundation advancing into the soil. After the Lead Section with the helical plates penetrates the soil, a Lead Displacement Plate and Extension are placed onto the shaft. Resuming torque on the assembly advances the helical plates and pulls the displacement plate downward, forcing soil outward to create a cylindrical void around the shaft. From a reservoir at the surface, a flowable grout immediately fills this void surrounding the shaft. Additional extensions and displacement plates are added until the helical bearing plates reach the minimum depth required or competent load-bearing soil. This displacement pile system does not require removing spoils from the site.

• HELICAL PULLDOWN® Micropiles use Standard Extensions.