深部岩体在掏槽爆破过程中的损伤演化机制

For the purpose of research on the damage evolution mechanism of deep rock mass in the process of cut blasting, a coupled model between the Cowper-Symonds hardening model and tension-compression damage model was implemented into commercial software LS-DYNA to simulate the damage evolution mechanism of deep rock mass in the process of cut blasting. The numerical results show that the in-situ stress and existence of free surface have an influence on the damage evolution mechanism of deep rock mass in the process of cut blasting. Since the in-situ stress exerts the resistance on the pressure load induced by blasting load in the rock mass, the damage scope of the rock mass surrounding the cut holes is influenced accordingly, and the damage scope decreases with the increase of the in-situ stress. However, in the process of cut blasting, the center hole as a free surface can enlarge the damage scope surrounding the cut holes. That is because the stress waves change into tensile stress waves upon the reflection at the free surface, here, and the tensile damage caused by tensile stress waves at the free surface propagates toward the inner rock mass, and eventually the damage scope of the rock mass surrounding the cut holes is enlarged.