Performance assessment of multi-unit pile-restrained H-shaped breakwater system

The hydrodynamic analysis for the multi-unit pile-restrained H-shaped breakwater inter-connected with inter-structural spacing is performed based on small amplitude wave theory. The H-shaped breakwater has proven to be an efficient structure due to its unique structural feature which assists in wave reflection and wave trapping efficiently. Therefore, the current study examines the efficiency of multiple breakwaters in maximising reflection and minimising transmission in the near-shore region. The structural analysis is performed by varying the width and submergence draft of the web and width of the flange of multiple H-shaped breakwaters to study the effect on various hydrodynamic parameters and horizontal wave force using the Multi-Domain Boundary Element Method (MDBEM). The MDBEM approach for the multiple breakwaters is derived considering the seabed flat and impermeable along with the fluid and structure-structure interface edge conditions. The present model based on MDBEM is validated with the established numerical results from the literature. The study confirmed that the pile-restrained dual H-shaped structures are especially beneficial in the region of intermediate water. Further, the lee side structure experiences the highest wave impact regardless of the number of structures, and wave reflection is improved by increasing the number of structures and decreasing the spacing between the breakwaters. The study observed that in the region of intermediate water depth, the seaside dual H-shaped structure is more susceptible to wave impact than the three-H-shaped structures.