Combined FEM/DEM Modeling of Triaxial Compression Tests for Rockfills with Polyhedral Particles

Abstract

Using a microscopic modeling approach, a simplification of the discrete element’s shape was done by using irregular convex polyhedrons to reproduce the geometry-dependent behavior of rockfills. Numerical modeling of the triaxial compression tests was conducted using a combined FEM and discrete-element method (FEM/DEM). The micromechanical properties of the numerical sample were calibrated to match the macroscopic response of the real material. The numerical results quantitatively agree with the laboratory results, which reproduce typical features of the mechanical behavior of rockfills, such as nonlinear stress-strain relationship, compaction, and shear dilatancy. The combined FEM/DEM simulation provides an opportunity for a quantitative study of the microstructure of particle assemblages, which give a better understanding of the mechanical characteristics of rockfills.