A three-dimensional deformable spheropolyhedral-based discrete element method for simulation of the whole fracture process

Abstract

A deformable spheropolyhedral-based discrete element method (DS-DEM) is proposed for predicting the evolution of fracture by coupling the finite element method (FEM) with the spheropolyhedral-based discrete element method (DEM). Under the framework of the proposed method, each rock mass is discretized into finite elements, and zero thickness joint elements are inserted along the boundary of finite element elements. The fictitious crack model and the Mohr-Coulomb failure criterion are employed to determine the failure state and failure mode of joint elements. The contact interaction between discrete particles and fracture surfaces is captured by the spheropolyhedral-based DEM. The method is verified by particle stacking test, three-point bending beam test, Brazilian disc tensile strength test, crack propagation in a single notched beam test, four-point bending beam test, and sphere impact test. The results of numerical simulations indicate that the proposed method is adaptable in simulating the whole fracture process of quasi-brittle materials including the initiation and propagation of cracks, as well as the collision and deformation of fragments.