Abstract:
The long-distance inter-basin water transfer project is an inevitable choice to solve the contradiction between water shortage and high-quality social and economic development.However, due to the constraints of topography and geological conditions, it is necessary to construct long-distance water conveyance tunnels across active faults.To understand the influence of the dislocation of the active faults on the deformation behavior of tunnel engineering, we took the Xianglushan Water Transfer Tunnel, the key control project of the Central Yunnan Water Diversion Project, as an example.Parameter analysis on factors such as different fault zone inclinations, angles, widths, and rock mass mechanical parameters was carried out, based on the displacement, relative deformation, maximum principal stress, longitudinal equivalent internal force and other indicators of each key part of the tunnel.The results showed that:(1) The larger the angle between the strike of the fault zone and the tunnel axis, as well as the inclination angle of the fault, the more favorable the deformation and stress state inside the tunnel lining.When the tunnel crosses active faults, a larger intersection angle is appropriate.(2) Given the same dislocation value, the smaller the fault width is, the more unfavorable it is for the tunnel.(3) When the rock mass on both sides of the fault zone is of the same quality and the fault dislocation value remains unchanged, the better quality of the fault rock mass, the more obvious the dislocation effect on the tunnel.These research results can provide meaningful support for constructing the related tunnel engineering.