3D Numerical Simulation of a Soil-Pile System Under Dynamic Loading

Abstract

In this research, a new modeling method for simulation of the dynamic behavior of a pile, which can be applied to the conventional finite difference analysis program FLAC 3D, was developed to reduce the calculation time. The soil domain in this method is divided into a near-field region and a far-field region, the latter of which is not influenced by the soil-pile dynamic interaction. The ground motion of the far-field is then applied to the boundaries of the near-field instead of modeling the far-field region with finite meshes. In addition, the non-linear soil behavior is modeled by using the hysteretic damping model, which determines the soil tangent modulus as a function of shear strain and the interface element was applied to simulate the separation and slip between the soil and pile. The proposed method reduced the calculation time by as much as two thirds compared to the usual modeling method, while maintaining the accuracy of the calculated results. The calculated results by the proposed method showed good agreement with the prototype pile behavior, which was obtained by applying a similitude law to the 1-g shaking table test results.