Experimental Studies on Low Crested Rubble Mound, Semicircular Breakwaters and Vertical Wall System

Submerged and low-crested breakwaters have been widely used as wave energy dissipaters along the coastline. Efficiency of the submerged breakwater depends on crest free board, crest width and its permeability. In the present study, interaction of the regular waves with the vertical wall, offshore low-crested rubble mound breakwater and perforated semicircular breakwater is investigated. Wave forces on vertical wall, transmission in the pool and the reflection from combined system are measured. The main aim of the present study is to know the hydrodynamic performance of the low-crested breakwaters. Maximum reduction of wave forces on the vertical wall was observed for zero submergence condition and longer pool length. Performance of semi circular low-crested breakwater was investigated in terms of energy loss coefficient which includes transmission and reflection coefficients.