Coupled DEM and FDM Algorithm for Geotechnical Analysis

Abstract

The purpose of this paper is to present a new algorithm for coupling discrete-element and finite-difference methods for three-dimensional problems. The finite-difference method (FDM) and the discrete-element method (DEM) are commonly used in geotechnical engineering. However, the continuous characteristics and the computational cost are the main obstacles to accurate and efficient simulation of practical problems for these individual methods. Coupling is thought to be an effective and promising way to combine the advantages and overcome the inability of these two methods. In this paper, an algorithm for coupling of DEM and FDM is presented. A two-stage searching method—namely, global domain searching and local domain searching—is proposed for detecting contact on the interface. A calculation method for force transmitting is presented. Conventional soil element tests were simulated to verify the validity of the proposed coupled algorithm by checking the constitutive behaviors, deformation compatibility, and transmission of normal and shear contact force.