Nonlinear analysis of flexible piled raft foundations subjected to vertical loads in layered soils

Abstract

In this paper, a simplified nonlinear approach is proposed to study the behavior of flexible piled raft foundations. The flexible piled raft is modeled as a thin plate with the finite element discretization. By employing the load transfer method, a nonlinear finite differential formulation for the analysis of a single pile is created. Pile groups are analyzed by the superposition principle. The interaction factor between two piles is determined by considering the interaction between a receiver pile and the surrounding soil. Based on solutions for the stress and displacement in layered elastic half space, the interactions between pile and soil surface, soil surface and pile, as well as soil surface and soil surface subjected to vertical loading are also taken into account to determine the flexibility matrix of the pile group-soil system. In order to verify the validity of the proposed nonlinear analysis method, calculated results are compared with the numerical and test results from the literature. The good agreement achieved shows that the proposed method provides a simple and useful tool for engineering design.