ABSTRACT
This study uses a validated three-dimensional finite element model to investigate the dynamic response of mountain tunnels subjected to combined reverse fault dislocation and earthquake. By applying various fault dislocations and seismic intensities, the deformation and damage evolution of the tunnel were analyzed. To clarify the impact of earthquakes on tunnel performance, the discrepancies in the tunnel’s behavior under fault dislocation with and without seismic activity were further examined. The results indicate that the most vulnerable sections of the tunnel structure are located near rupture surfaces. Based on the analysis of damage degree and distribution, the appropriate length for anti-seismic tunnel reinforcement was recommended. Notably, under reverse fault dislocation, the combined effect of an earthquake can cause significantly greater damage to tunnels. This study offers a useful reference for assessing post-earthquake reinforcement and upgrade strategies for tunnels traversing active fault zones.
