A structure-decomposition approach for dynamic analysis of sheet-pile groins subjected to tidal bores

In this study, a novel theoretical method is proposed for studying the dynamics of sheet-pile groins under impact loads. This methodology employs the principle of structural decomposition and segments a complete structure into a series of portal frames interconnected by a straight beam in conjunction with a set of singular piles topped by a curved beam. Initially, the dynamic impedances of a portal frame comprising two piles, a short beam, and a single pile were evaluated. The real and imaginary components of the dynamic impedance are physically equal to the spring and damper, respectively. They were subsequently attached to straight and curved beams. Finally, the beam dynamics are evaluated using the transfer matrix method. The proposed method was verified and validated using existing research data and experimental model findings. Using this method, parametric studies can be efficiently performed on the dynamic characteristics of sheet-pile groin structures, that is the deflections and internal forces in both straight and curved beams. Their research revealed a notable increase in the deflections and internal forces in both beams as the short beam spacing increased. Compared to the deflection and internal force of the straight beam, those of the curved beam were more affected by alterations in the pile row spacing.