To ensure work space in the water by removing mud deposited on the bottom of water without a problem of water contamination by use of a structure which is good for work execution and can be easily removed after the completion of works in the case of constructing a bridge pier.
Corrugated sheets 17 with a radius enough for ensuring the work space in the water are connected to each other in the horizontal circumferential direction and in the vertical direction to assemble a corrugated pipe 18, and a knife edge member 19 made by a steel plate is fixed to the lower end of the corrugated pipe 18 to construct a water mudiness preventing steel frame. The steel frame is set in the mud 14 at the bottom of the water, thereby removing mud in the range surrounded with the steel frame. This setting of the steel frame and removal of mud 14 are performed until reaching the top of the foundation 13. In the case of ensuring the work space 1 in the water in the periphery for reinforcing the existing underwater bridge pier 11, the corrugated pipes 18 are assembled in such a manner as to surround the underwater bridge pier 11.
ISHIKAWA HIDEYA
MORITA AKIHIRO
