PURPOSE: To promote wave dissipation performance and, at the same time, to facilitate construction work and to reduce construction cost by forming a bag body of a membrane material with flexibility and raising a position of the upper surface of the bag body higher than the water level at the high water level in the case the bag body expanded with filling of fluid thereinto is installed at the bottom of the water.
CONSTITUTION: A bag body 13 is formed of a membranous flexible material. The bag body is mounted on the fixed base 12. After that, the bag body is expanded with the filling of fluid thereinto, and a height position of the upper surface 13a of the bag body is raised higher the water level WL at the high water level. Accordingly, waves rolled in are absorbed with the motions of the bag body 13 to dissipate the waves. The waves rolled in from the offing are covered with the bag body 13 to prevent surely the transmission of them. According to the constitution, labor and time required for construction work in a construction field are greatly reduced and, at the same time, the alteration, removal, etc., of an installation position of a breakwater are easily carried out, and wave dissipation efficiency can be promoted.
HORI TETSUO
TANAKA MASAHIRO
