Effect of Super Structural Symmetry on Pile Foundations Under Pseudo-static Loading

Abstract

Pile foundations are very common in use for multi-story buildings having complex shapes, sizes and loading patterns. Thus, it is extremely important to estimate the foundation behavior under dynamic loading to avoid any catastrophe and/or failure of serviceability conditions. In view of that, the present study is envisaged to investigate the behavior of pile foundations of symmetric and asymmetric buildings under earthquake load. The study has performed the displacement analysis of piles with different configurations as mentioned including the pile length. For this purpose, a seven-story building is modeled in different symmetric and asymmetric configurations (shapes). The behavior of piles, positioned along the periphery of superstructure, is monitored based on different parametric variations. A finite element software, PLAXIS 3D, is used for this investigation program. The pseudo-static method is adopted to determine the displacement of piles under dynamic loading conditions. Responses of piles, along the depths, are monitored by gradually increasing the horizontal acceleration. It is found that pile displacements at various depths in symmetrical buildings (e.g., square and/or rectangular shapes) are higher than unsymmetrical buildings (e.g., ‘E’, ‘L’ and ‘T’ shaped, etc.) under similar horizontal acceleration. Further, it has been noticed that displacements of individual piles at various depths for a symmetrical building are the same; while it is different for an asymmetrical building.