Pull-Out Capacity of Granular Anchor Piles in Expansive Soils

The stability of structures founded in expansive soils depends upon their pull-out capacity or resistance. The pile foundations adopted to alleviate the damages to the structures resting in these soil fail due to their inadequate pull-out capacity. In an attempt to develop a simple, easy to install and cost-effective alternative foundation system to the conventional concrete piles, the possible use of granular anchor piles below shallow footings was studied by conducting pull-out tests in the field after conducting pilot tests in the laboratory. From these studies, it is found that the pull-out resistance of granular anchor piles is more than twice the value of concrete piles in both unsaturated and saturated states. The pull-out resistance of concrete and granular anchor piles is decreased by about 32% and 25% respectively upon saturation.