Hydrodynamic Performances of Pile-Restrained Floating Breakwaters with Arbitrary Plan Shape

This paper is concerned with hydrodynamic performances of pile-restrained floating breakwaters of the same material volume, but with different plan shapes. The performances are evaluated in terms of the wave attenuation performance and the breakwater heave motion. The wave attenuation performance is assessed by using the mean transmission coefficient or the upper limit of the 95% confidence interval of the transmission coefficients in the breakwater’s leeside. The transmission coefficients and the breakwater motion are obtained from numerical simulations based on the linear wave theory and the Mindlin plate theory. The hybrid Finite Element—Boundary Element (FE-BE) method is employed for solving the fluid-interaction problem, and its accuracy is verified by comparing with available published results. It is found that by altering the breakwater plan shape, the wave attenuation performance may be improved by up to about 60%, and the breakwater heave motion may decrease by more than 90% when compared to those of the conventional straight breakwater.