Lining Structure of Water Conveyance Tunnel under Earthquake Action Research on Damage Law

Based on the concrete damage plasticity constitutive model (CDP model) of ABAQUS software, the dynamic response of high pressure internal water conveyance tunnel during earthquake is simulated, and the dynamic response and dynamic damage law of high internal water pressure water conveyance tunnel structure under surrounding rock grade, buried depth and seismic wave intensity are analyzed. The research shows that the surrounding rock grade is closely related to the dynamic response and damage characteristics of the lining structure of the water conveyance tunnel. The dynamic damage of the tunnel under grade Ⅲ surrounding rock is only 0.08, which is far less than 0.83 under grade Ⅳ surrounding rock. It can be considered that it will not cause great damage to grade Ⅲ surrounding rock under earthquake. The surrounding rock grade is better, which can provide more stable support and reduce the stress and vibration of the structure. If the tunnel is in the seismic zone, the buried depth can be used as one of the design control indexes in the tunnel design. The lining damage is mainly distributed at the top and upper arch waist of the tunnel. With the increase of the buried depth of the tunnel, the dynamic damage amount increases from 0.021 to 0.081, then to 0.085. the damage of the lining structure also increases. This may be because the deep buried tunnel is more constrained by the underground rock and soil layer, thereby reducing the transmission of seismic load. The change of seismic wave intensity can directly affect the damage characteristics of tunnel lining structure. The dynamic damage mainly occurs at the vault and arch waist, and the damage area expands from the vault and arch waist to the side wall and corner. The increase of seismic wave intensity will lead to dramatic changes in the stress of the structure, which will lead to more complex and serious damage.