Pore pressure on subsea shield tunnel lining subjected to wind-wave action

With the advancement of offshore engineering, the application of submarine tunnels has become increasingly widespread. Previous studies have paid little attention to the accumulation of pore pressure in the tunnel lining during tunnel excavation under complex marine environment. In this study, a simplified analytical solution is established to consider the combined effect between the wind-wave parameters and the seabed inclination. Using Stokes' second-order nonlinear wave theory and Biot's dynamic consolidation equations, the governing equations are numerically solved to derive seepage solutions under combined wind-wave loading. Then, the proposed model is validated with both the wave tank tests and finite element simulations. Finally, the influence of key parameters on the safety of submarine tunnels, including seabed properties, wind and wave characteristics, and tunnel design parameters, is analyzed. It is found that free-field pore pressure shows a “U”-shaped distribution, while tunnel-induced pore pressure forms a “W”-shaped spatial pattern. Both oscillatory and cumulative pore pressure magnitudes around the tunnel progressively decrease with increasing seabed slope angles. Under sloped seabed, higher wind speeds and longer wave periods, combined with shallower water depths, intensify the wind-wave-induced dynamic pressure on the seabed surface. This study provides an efficient analytical solution for assessing pore pressure accumulation around a submarine tunnel embedded in the seabed.