PREVENTION OF MUDDLING OF WATER IN JET STIRRING TYPE UNDERWATER BOTTOM GROUND IMPROVEMENT WORK

摘要

PURPOSE:To prevent the muddling of water by forming an air or water curtain to surround the region heading from the upstream underwater bottom in the improvement area toward the water surface. CONSTITUTION:In improving bottom 8 under water by means of a drive unit 3, a stirring shaft 6, and a stirring blade 9 provided on a hull 1, four pipes 13a, 13b, 13c and 13d are set above an improvement area 14 in proximity to the bottom 8, and nozzle ports (not illustrated) are provided upwards for every a fixed pitch over the whole length of the pipes 13a-13d. Air, for example, is jetted from the nozzle ports to form an air curtain in a square form (by plane view) from the bottom 8 toward the water surface in such a way as to surround the upper part of the area 14, while the ground is improved.