Numerical Procedure for Dynamic Simulation of Discrete Fractures Due to Blasting

Abstract

This paper describes development of a generic nonlinear, dynamic modelling technique to simulate discrete rock fractures due to blasting using the finite element method. The element elimination technique together with a brittle, Rankine failure-type material model are used as a means to simulate the initiation and growth of fractures in the rock under the effect of blast-induced dynamic pressure pulse. Dynamic loads representing ideal and non-ideal detonations are simulated and a new method, termed as optimised pressure profile, is proposed to approximate the pressure-time profile of the blast load to model the dynamic load. Comparison of numerical model results with previously reported observations from the literature reveals the ability of the model as a predictive tool and supports the validity of the developed modelling procedure.