Effects of Oblique Incidence of SV Waves on Seismic Response of Prefabricated Utility Tunnel Joint

Aiming at the problem of the seismic response of the joint of utility tunnel subjected to the inclined incidence of SV wave under the action of shallow earthquake, based on the theory of wave input, the incident earthquake motion was modeled as equivalent nodal forces applied to the viscous-spring artificial boundary, the nonlinear spring element was introduced to simulate the mechanical behavior of the utility tunnel interface, and the seismic response of the utility tunnel joint was calculated by the dynamic time history analysis method. Based on the water-proof failure limits of the joint deformation and rotation limits of the comprehensive utility tunnel on the double rubber sealing on sliding surface of utility tunnel joint, the safety evaluation of the joint deformation and rotation under different incidence angles of SV wave was given. The analysis results show that the response of deformation by SV wave at the junction of utility tunnel decreases first and then increases. When the incident angle is 30°, the horizontal deformation of the utility tunnel joint is the largest. When the incident angle is within the range of 20°-30°, the rotation of the utility tunnel joint exceeds the corresponding safety limits, and the water-proof failure of the utility tunnel joint occurs. Considering the water-proof failure of the utility tunnel joint under different incidence angles of SV wave, it can provide a technical reference for the functional integrity and safety design of the utility tunnels.