Numerical modeling of rock failure in drilling blasting under the effect of explosion-induced stress waves

Blasting-induced rock failures are resulted from the loading effects of explosion-induced stress waves and explosion gas pressure. In this paper, rock failure under the former effect was numerically modeled by the discontinuous deformation analysis (DDA). Firstly, the DDA was verified by the simulation of a Hopkinson spalling model. It shows that wave propagations in rock and the resulted rock dynamic fracturing can be accurately modeled. Thereafter, drilling blasting simulations were conducted by applying triangular shock loads on the borehole walls. Rock failures including the fracturing surrounding boreholes, the spalling near the free surface, the formation of the crater-shaped fragmentation domain, the crack evolution in the relatively far region, and the cast of rock were numerically reproduced. The failure process was analyzed combining the simulated stress wave propagation process. This work is the basis for the further simulation of rock blasting considering both blasting loading effects.