Effects of submerged structure on rubble-mound breakwater: Experimental study

Abstract

Breakwaters are generally constructed to protect the port and harbor facilities from dynamic forces of the ocean wave. However, stability problems of breakwaters have been issued due to the global warming, which causes the rising of sea level. A submerged structure, more effective method for resolving such problem, can be expected to improve stability and practicality of the breakwater. For several decades, many researches for interaction waves and submerged structure have been carried out by changing the wave parameter or submerged structure dimension. Based on results from laboratory experiments, the reflection coefficient and the run-up height of breakwaters are investigated for different widths and heights of the submerged structure with different distances between adjacent two breakwaters. We found that the reflection coefficient decreased as the wave steepness increased. We also found that the run-up height decreased because the wave breaking and reflection due to a submerged structure, the relative height of a submerged structure normalized by flow depth. Therefore, the dissipation of the incident wave energy plays an important role improving the stability of the rubble-mound breakwater more stable. The experimental outcomes can be a feasible design criteria of a submerged structure.