Investigation into energy conversion and distribution during brittle failure of hard rock

A better understanding of energy evolution during brittle failure of hard rock is critical for safe excavation of underground openings, insight into rockburst phenomena, and earthquake mechanisms. According to Griffith’s theory of crack propagation, the mechanical behavior of rock during crack propagation is analyzed from a theoretical perspective, and the conversion and distribution of elastic strain energy during crack propagation are then investigated. The analytical experiments are then carried out as a series of uniaxial compression tests of Silurian Longmaxi shale samples using a novel setup that combines X-ray micro-computed tomography with a uniaxial loading apparatus. Results show that the theoretical framework which describes energy conversion and distribution is reliable. On this basis, the evolution characteristics of energies, including elastic strain energy and surface energy, during the brittle failure process of hard rock are revealed. The results may provide a theoretical basis for the mitigation and prevention of rock-induced disasters.