This paper proposes a new continuum damage model accounting for inertial effects (Keita et al 2014) to analyze the fracture behavior of rock in tension due to blasting. The two-scale damage model is fully deduced from small-scale descriptions of dynamic micro-cracks propagation under tensile loading (mode I). An appropriate micro-mechanical energy analysis is combined with homogenization based on asymptotic developments in order to obtain the macroscopic evolution law for damage (Dascalu et al 2008).
The global macroscopic response predicted by the model is obtained by implementation of the dynamic damage law in a transient finite elements code. The damage pattern around the blasthole was simulated. Numerical simulations were able to illustrate the ability of the model to reproduce the radial cracks zone due to rock blasting. The influences of microstructural size and of micro-cracks orientation on damage distribution around the blasthole have been determined.