Evolution Mechanism Characteristics Research of Cross Active Fault Tunnel Based on 3D Fine Numerical Simulation Analysis Method

A large number of hydropower and pumped storage projects are being constructed in the strong earthquake prone areas of western China. Hydraulic tunnels will inevitably cross active faults and are affected by the movement of active faults. These hydraulic tunnels face serious threats of faults. In response to this issue, a three-dimensional fine numerical simulation analysis method is adopted, and based on the established fine numerical simulation model, the calculation and analysis of the Class IV surrounding rock section of the hydraulic tunnel are carried out. The evolution mechanism of the surrounding rock and the influence of fracture and displacement on the tunnel structure are discussed. The conclusions obtained can provide some reference for the anti misoperation design of tunnels crossing active faults.