Numerical assessment of non-uniform terrain and inhomogeneous wave–current loading effects on the dynamic response of a submerged floating tunnel

The submerged floating tunnel (SFT) has broad application prospects in straits and bays with deep water levels. However, few studies have focused on the impact of non-uniform terrain and inhomogeneous wave–current loads on an SFT. Therefore, this study establishes an inhomogeneous wave and current environment along the Qiongzhou strait through a numerical hydrodynamic model which is validated using measured data from the published literature. Based on the simulated wave–current environmental conditions, the effect of inhomogeneous loading on the SFT is considered under five working conditions through finite element (FE) analyses. In addition, this paper adopts a new sampling approach to reduce the chance of random events. The results show that the dynamic response of the SFT is significantly correlated with water depth and that an inhomogeneous wave–current condition will result in the smaller horizontal response of the SFT compared to the homogeneous wave–current condition. Furthermore, this study also discusses the changes in mooring cable force on the wave-ward and leeward sides. The oblique cable force on the leeward side is less than that on the wave-ward side, but the fluctuation of the oblique cable force on the leeward side is greater than that on the wave-ward side.