Performance of a Double-Walled Barrier with a Front Wall of Inclined Plate Array

摘要

In order to mitigate secondary effects caused by high reflection waves from a conventional curtain-walled breakwater, a new type of breakwater consisting of two different walls was proposed. One wall is impermeable and located on the shore side of the breakwater. The other is consisted of an array of inclined plates with the same gap and located on the offshore side. It is presumed that the distance between the two walls is comparatively narrow for economical design, e.g., having a similar size to the width of its super structure. The mechanism of effective dissipation of wave energy is to enhance the generation of vortex flows from the walls, especially from the plate-array wail. By using the Helmholtz mode wave resonance between the two walls, enhancement of the vortex flow is realized. It was confirmed that a donble-curtain walled breakwater with a front wall of inclined plate array is very effective to reduce both the reflected and transmitted waves. It was also seen that the performance of the proposed breakwater varies only a little with large tidal differences as usually observed in the Seto-Inland Sea.