ABSTRACT
This research aimed to tackle practical engineering problems including high geo stress, high seepage pressure, and dynamic disturbance in the blasting excavation of the Yuelongmen tunnel. Numerical simulation software COMSOL Multiphysics was used to establish a numerical model based on the Mohr-Coulomb failure criterion and the theory of continuum damage mechanics. On this basis, the Spatio-temporal evolution of the stress field, seepage field, and damage field of the tunnel under different seepage water pressures and fault conditions during blasting excavation was investigated. The results show that the seepage water pressure has significant influences on water inflow in the tunnel while exerting small influences on the severity of damage to the surrounding rocks. As the fault-zone length increase, damage to the surrounding rock and water inflow in the tunnel both changes significantly and the fault-zone thickness exerts larger influences on water inflow to the tunnel. If the fault is located above the tunnel, the seepage water pressure has the greatest seepage effect on the tunnel and water inflow in the tunnel is also maximized.
