A pre-engineered tieback system for earth retention supplied by the largest manufacturer of anchors in the world simplifies the challenges for contractors. These tieback anchors are installed by rotating the anchors into the ground with common rotary drilling equipment.

Once the minimum depth is obtained the capacity can be determined by reading the installing torque and correlating it to the holding capacity ratio. 

Capacities to 200,000 pounds per anchor are obtainable with this system. Proven on hundreds of applications these cost effective tiebacks can be tested immediately. No concrete to wait for curing! This saves time and money plus improves schedules.

Tie Back Anchors
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. 

The HELICAL PULLDOWN Micropile also develops additional capacity by combining both end-bearing on the helical plates and skin friction along the rough surface of the grout column. The result is a higher capacity pile system.

The HELICAL PULLDOWN Micropile could be just the Deep Foundation Solution you’re looking for . . .put it to work on your next project

The proven Chance Helical Pier® foundation underpinning system provides these benefits:

Cost effective and technically superior to other remedial piering methods.
Predictable results; known capacity in specific soils.
Installs with limited access - no concrete trucks, heavy equipment, or grout pumps.
Limited excavation - site is minimally disturbed.
Used for new construction, enhances foundation strength on sites with poor soil conditions.
Seismic-resistant option may be added during rehab or in new buildings.
Where state or local laws require engineering consultation or planning for foundation work, consider the Chance Helical Pier underpinning system. Its low environmental impact makes a viable alternative recognized by governmental and building officials.

Many other compression and tension challenges have been solved by Chance helical anchors:
Tieback tendons, micropiles, and soil nailing are among the uses based on Chance anchor technology developed and applied over more than 80 years. 

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