Auger Cast Piles (ACPs) are common in New Mexico and some surrounding states. Straight Line Construction has installed thousands of smaller diameter augercast piles for solar applications.
What are Auger Cast Piles?
Auger cast piles are non-displacement, composite steel and grout deep foundation elements. Auger cast piles are designed as friction elements utilizing the skin friction between the grout body and the surrounding soil to obtain their capacity. Auger cast piles are typically relatively mildly reinforced. Typical auger cast pile sizes range from about 10 to 24 inches in diameter.
How are auger piles installed?
Augercast piles are installed utilizing a hollow-stem, continuous flight auger (CFA). The auger is advanced to the design bearing depth while continuously rotating the auger. Once the designed bearing depth is reached, a cement or sand and cement grout is pumped through the hollow auger so that the grout is placed from the bottom of the shaft up. Once a grout head of about 5 feet is established above the auger tip, the auger is slowly withdrawn while still rotating and continuously pumping grout to maintain the grout head. Drill spoils are brought up the auger by the rotation and the auger is withdrawn until all of the drill spoils are removed and clean gout is at the surface of the shaft. The reinforcing cage and center reinforcing (if any) are then wet set into the fresh grout.
What benefits can auger cast piles provide on my projects?
Auger cast piles can effectively transfer relatively high loads through skin friction to obtain required design loads. Auger cast piles can also be installed relatively quickly as compared to traditional drilled shafts. Depending on soils and loading conditions, auger cast piles can offer an economical alternative to traditional drilled shaft construction.
In what applications can auger cast piles be used?
Auger cast piles can be utilized in most of the same applications as traditional drilled shafts including:
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Construction of new foundations
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For design of secant pile wall systems
What advantages do auger cast piles provide?
Some of the advantages of augercast piles include:
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Relatively economical compared to traditional drilled shaft construction
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Faster installation than drilled shafts