Dynamic responses of the sheet–pile groin under tidal bore considering the soil–structure–water interaction

A sheet–pile groin composed of two rows of piles connected by sheets has been applied to resist tidal bores. This study develops an analytical framework to thoroughly investigate the dynamic responses of the sheet–pile groins under tidal bores. The piles are modeled as an Euler–Bernoulli (EB) beam, while the sheet is simulated as a Rayleigh–Love rod and an EB beam considering the vertical flexural inertia effect. The hydrodynamic pressure is calculated by using radiation wave theory. The saturated soil around the piles is described with dynamic Biot’s poroelastic theory, while the additional mass model adopts the interaction between the piles. The applicability and correctness of the formulas are verified by comparing them with numerical simulation results. It investigates the influence of water depth, sheet length, pile radius and the ratio of the soil–pile modulus on the dynamic impedance of the sheet–pile groin. Suggestions based on this study are given to guide sheet–pile groin design to avoid the resonance frequency and improve the impedance in practice engineering.