Auger Cast Piles 1

[jakeh76]

What are the primary differences in "Auger Cast Piles" and Cassions? Is there another name for an "Auger Cast Pile" Any good references for design? Thanks.

 

[GeoPaveTraffic]

Auger cast piles, also know as augered-cast-in-place ACIP, are different from cassions in several ways. The biggest difference is that the piles are grouted through the auger as the auger is withdrawn from the ground leaving the pile in place; whereas cassions are drilled, the auger removed, then the concrete placed. This difference makes inspection much more difficult on ACIP piles than on cassions. Other differences, not an exhaustive list, are listed below.

1. grout is used for the piles instead of concrete
2. max diameter for ACIP piles is about 24 inches, though some contractors can go larger for relatively short piles.
3. ACIP piles are almost always installed in groups, i.e. like piles, not singles like most cassions.
4. depth of installation is not much of an issue for ACIP
5. installation of reinforcing steel is much more difficult and unsure with ACIP piles than with cassions

As for design, ACIP piles are designed using both driven pile and cassion methods. With reasonable correlations to both under differing site conditions. There have been several studies done in the last few years, I will try to locate references and post them later today.