Shaking Table Test and Dynamic Response Analysis of Saturated Soil-Submarine Tunnel

With the increasing construction of undersea tunnels in seismic-prone areas, accurately assessing their response to seismic conditions is crucial. To grasp the dynamic response of undersea tunnel structures to seismic waves, the shaking table test of water-sea-sea submarine tunnel is designed and carried out based on the methods of orthogonal design and fuzzy method. A comprehensive time-domain model is developed to capture the nonlinear dynamic interaction of ocean engineering structures, taking into account seismic waves, seawater, and saturated soil. The research results show that as the burial depth at each measurement point of the submarine tunnel increases, the acceleration response decreases and the horizontal displacement relative to the seabed surface increases. Comparing test and finite element simulation results reveals that under seismic loading, the strain distribution pattern of the tunnel section is mainly in the arch shoulder, waist, and foot with larger strain peaks, whereas the strain peaks at the arch top and the superelevation arch are smaller. Simultaneously, doubling the water pressure induces a slight increase in the overall strain response peak of the tunnel, with an indistinct relative displacement change rule. When a vertically polarized shear wave (SV wave) is vertically incident, different dynamic response indices will have different trends with the change in water level. This study may provide a reference for shaking table tests for saturated soil-submarine tunnels at complex sites.