The Spatio-Temporal Evolution of Rock Failure Due to Blasting under High Stress

Abstract

The research aims to investigate the failure characteristics of rock caused by blasting under high stress, explore the energy generation and its transfer and release in rock under the effects of blasting. Physical experiments and numerical simulations were performed. The results showed that, as with AE time-series data, the attenuation time of the AE activity increases with the number of blasting events, thereby decreasing the overall stability of the samples. In terms of AE spatial evolution, different initial stress fields play a role in directional guidance in initiation, propagation, and coalescence of blasting-induced cracks. The direction of propagation of microcracks is consistent with the direction of the maximum principal stress. The blasting-induced disturbance in a high-stress state accelerates the extension and propagation of microcracks and is accompanied by the occurrence of numerous high-energy AE events. Numerical simulation showed that the maximum principal stress exhibits a guiding effect on the propagation of blasting-induced cracks and the pattern development of the damage zone, which is consistent with the conclusion of physical experiments. The research provides a theoretical guidance for designing and optimising the blasting parameters of deep rock.