Numerical simulation of the complete rock blasting response by SPH–DAM–FEM approach

Abstract

Rock mass blasting is a complex process which involves the coupling of both discontinuous and continuous media. This paper aims to provide a numerical simulator capable of reproducing the complete blasting response in rock mass by incorporating large deformations, damage distribution and blasting vibration with a single numerical model. A Smooth Particle Hydrodynamics (SPH) algorithm and a modified blasting damage model were introduced into the explicit finite element code LS-DYNA with a subroutine interface in order to develop the coupled SPH–DAM–FEM numerical simulator. The coupled SPH technology with the modified Damage model is used to simulate the near zone in the blasting process and the FEM to capture the far field response of the rock. The complete dynamic response of a presplit blast and a bench blast was investigated with the developed coupled model in two case studies regarding a blasting excavation of high rock slopes in China. The discontinuous characteristic of the blast process, large deformations and damage were analyzed carefully. The reproduction of the damage contour and vibration was compared with site measurements. From the analysis conducted, it is shown that the results produced by the developed coupled model match quite well with field observations. This demonstrates the capability of the proposed coupled model. To complete the analysis, a sensitivity analysis of the main SPH parameters was studied parametrically to obtain a better understanding and expose more capabilities and applications of the proposed coupled approach.