HELICAL PULLDOWN® Micropile
Higher load capacities than ever now are achievable by the
patented HELICAL PULLDOWN® Micropile technology. It continues
to overcome obstacles to traditional foundation methods for
a growing number of applications.
These products serve heavy anchoring markets with
tension loads of 70,000 lbs to 200,000 lbs and compression
loads of 20,000
to 400,000 lbs.
What is a HELICAL PULLDOWN® Micropile?
The HELICAL PULLDOWN Micropile is a system for constructing
a grout column around the shaft of a standard Helical Pier
Foundation Systems 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.
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 this system include:
Resistance to buckling in weak surface soils
Stiffer pile (deflects less at a particular load)
Additional corrosion protection in aggressive soils
Placed as composite steel and concrete pilings
they have advantages of:
No vibration to adjacent buildings
All components can be individually designed
Dedicated equipment NOT required
Predictable and reliable capacities
Cost effectiveness (especially viewed as dollars per completed
For More Information:
Structure Support - Bulletin 02-0101