Group interaction analysis of displacements in granular pile anchors (GPA)

Abstract

Granular piles improve the behavior of the ground by increasing bearing capacity, reducing settlements, accelerating consolidation, and mitigating liquefaction related damages by reinforcement and densification effects. GPs due to their inherent nature can resist compressive and shear loads but not tensile ones. Granular piles can be made to resist pullout or uplift forces by placing an anchor at the base and attaching the same by a cable or rod to the footing to transfer the applied pullout forces to the bottom of the GP. Such an assembly is termed a Granular Pile Anchor (GPA). Analyses for displacements in granular pile anchors in groups of two, three or four, are presented based on Poulos and Davis (1980) for rigid piles. Results are presented as variations of interaction factor, 'α' with spacing s/d and relative stiffness factor, K. The results compare well with those of Poulos and Davis for rigid piles. The principle of superposition is validated for groups of 3 and 4 GPA.

Behaviour of Granular Anchor Pile (Gap) and Group Piles In Different Type of Soils under Vertical Pullout Loads

“…Kumar and Kumar [10] proposed granular pile system is a variable means for ground improvement. Vidyaranya and Kumar [11] analyzed the displacements in granular piles in groups of two, three or four presented based on Poulos and Davis (1980) for rigid piles. Kumar ( 2002 ) [12] reported the laboratory and field study of GAP system under axial pullout loads.…”