Energy evolution and stress redistribution of high-stress rock mass under excavation distribution

In order to reveal the mechanism of the occurrence of deep engineering catastrophe and the influence of various factors on excavation perturbing effect, the models with different original stress states and different excavation sections are established by using the distinct element numerical simulation software PFC. Through explicit calculation, the kinetic release curves of high-stress rock mass under various circumstances are gained, and the peak and final stable values of the obtained curves are regarded as energy indices, which are used for representing the disturbance intensity and the stability degree of the excavation system respectively. The analysis based on these indices shows that the excavation with a circular cross section will induce the minimum disturbance effect under a nearly hydrostatic pressure stress state. The stress redistribution characteristics of high original stress rock mass excavated by different sections are also studied. Through the inspection of stress redistribution course which is regarded as an unloading process, the influence mechanisms of the original rock mass stress state and the geometry of excavation section on the stress redistribution are revealed ultimately.