Development of a GPGPU-parallelized 3-D FDEM with a novel and simple implementation of extrinsic cohesive zone model

This paper proposes a novel and simple master-slave (MS) algorithm to realize the parallelization of the extrinsic cohesive zone model (ECZM) in the 3-dimensional (3-D) combined finite-discrete element method (FDEM) based on the general-purpose graphics processing unit (GPGPU) for simulating dynamic rock fracture. The newly proposed algorithm is superior than the complex adaptive re-meshing algorithm, which has been applied in literature to implement ECZM but has difficulties if not impossible in being parallelized for running on GPGPU. Verifications and validations of the developed 3-D ECZM-based FDEM are then carried out through the simulations of the dynamic tensile and compression strength tests of rocks using the split Hopkinson pressure bar (SHPB) system and the rock blasting tests, which are compared against the experimental observations. It is concluded that the developed 3-D ECZM-based FDEM has the capability of simulating stress wave propagations more smoothly and fracture patterns more consistent with the experimental observations, which may promote further applications of 3-D FDEM to model dynamic rock fracturing.