摘要 |
PROBLEM TO BE SOLVED: To make compact a wave absorbing structure by providing a vertically hanging plate at the front of an impermeable breakwater so as to be spaced a required gap away from the breakwater and to have a gap from the sea- bottom. SOLUTION: A wave absorbing structure 1 is formed of a vertically hanging plate 4 which is vertically provided in a manner protruding from the sea level, at the front of an impermeable erect breakwater 2, so as to be spaced a required gap B away from a front surface 2a of the erect breakwater 2, while having a gap from the sea-bottom 3, with a draft depth (d). The vertically hanging plate 4 is formed of concrete or a metal, which, however, is not limitative, and has a length which nearly reaches the sea level 5. The thickness of the vertically hanging plate 4 is set as appropriate, depending on increase in whirlpool at a lower edge 4a of the vertically hanging plate 4. Thus, a phenomenon of increase in the whirlpool at the lower edge 4a of the plate 4 by wave resonance in a piston mode is generated in a retarding chamber C defined between the erect breakwater 2 and the vertically hanging plate 4, to thereby scatter (cancel) reflected wave energy and calm down waves. Further, the entire of the wave absorbing structure can be made compact. |