Granular Anchor Pile System for Resisting Uplift: A Review

Granular anchor pile (GAP) system is a modified stone column in which the stone column is reinforced using an anchor rod with an anchor plate placed at the bottom. The anchor rod is embedded in the footing of the structure which rests on the stone column. This system prevents the uplift of the structure which may be caused by uplift forces like the presence of expansive soil below the footing, wind forces, or buoyant forces. This paper presents a review about the application of granular anchor piles, the conditions in which it can be used and the method of installation. A discussion on the parameters like length, diameter, soil type, and its strength which influences the uplift capacity of the granular anchor pile is also given.