CCFA

Cased Continuous Flight Auger (CCFA) piles

Cased CFA piles utilize dual rotary drilling techniques where the outer temporary casing rotates in an opposite direction from the inner continuous flight auger.  It is generally used where borehole stability is required such as drilling a secant wall or piles immediately adjacent to a building. Concrete is then tremied through the hollow stem, stabilizing the borehole hole as the auger is slowly retrieved.  Once the auger is removed from the ground and the borehole is filled with concrete, steel reinforcing is placed.  The steel reinforcing can consist of a circular cage,  one center bar, or both.