Seismic response of non-connected piled raft foundations

摘要

Connected piled raft foundations (CPRFs) have proven to support heavy structures under vertical load. However, when subjected to seismic loading, significant load transfer from the raft beneath to the pile head may cause huge shear stress and bending moments in the piles. Thus, this paper investigates the behaviour of non-connected piled raft foundations (NCPRFs) subjected to earthquake loading. For this purpose, a three-dimensional finite element model was presented and validated against centrifuge test results. This numerical model was then employed to perform a series of numerical analysis. According to the results, pile slenderness ratio and raft thickness can be considered as essential factors in evaluating the dynamic response of NCPRF. The comparison of CPRF and NCPRF has also indicated that using NCPR system leads to significantly less shear force and bending moments along the piles, which results in less required reinforcement and more economical design in comparison with CPR systems.