CHANCE Helical Pulldown Micropiles

CHANCE Helical Pulldown Micropile

 


What is a Helical Pulldown Micropile?

The Helical Pulldown Micropile is a system for constructing a grout column around the shaft of a standard CHANCE Helical Pier Foundation System pile.

To begin the process, a screw anchor is placed into the soil by applying torque to the shaft.  The helical shape of the bearing plates creates a tremendous pulling force that keeps the anchor advancing downward into the soil.  After the lead section with the helical plates penetrates the soil, a Lead Displacement Plate and Extension are bolted onto the shaft.  Resuming torque on the assembled shaft advances the helical plates and pulls the displacement plate downward, forcing soil outward to create a cylindrical void around the shaft.

 

micropile-uncased

micropile-cased

 

From a reservoir at the surface, a flowable grout immediately fills this void, surrounding and encapsulating the shaft.  Additional extensions and displacement plates are added until the helical bearing plates reach competent load-bearing soil.  This displacement pile system does not require removing spoils from the site.

 

Benefits of the system include:

  • Resistance to buckling in weak surface soils
  • Stiffer pile (deflects less at a particular load)
  • Additional corrosion protection in aggressive soils

 

For more information, please follow the link below:

 

Pulldown