Deformation of granular soil under combination of principal stress value and direction change

Abstract

Soil is often subjected to complex three-dimensional stress paths in geotechnical engineering. It is difficult to achieve such complex stress paths in laboratory tests. To this means, discrete element numerical simulations are carried out on cross-anisotropic granular material by using PFC3D in this study. The response of granular soil under three-dimensional seismic load is simulated and compared with results from corresponding pure principal stress magnitude change or direction change scenarios, illustrating the importance of principal stress value and direction combination on the mechanical behavior of soil. Simulations of three kinds of idealized stress paths are then conducted and discussed. In the idealized stress path simulations, the deformation and micro-scale fabric evolution is observed to be most significant under pure direction change.