| 摘要 |
PURPOSE:To prevent the pollution of sea area due to floating of sludge by preventing the leak of compressed air by using a system in which a hollow pipe is drawn out of soft ground at the seabed while controlling the pressure of compressed air in the pipe in such a way that the pressure of sand at the lower part of the hollow pipe is matched with the pressure of the surrounding soil. CONSTITUTION:Compressed air is sent into a hollow pipe 1 from a compressed air supply pipe 8 through which sand is packed into the hollow pipe 1, and also an appropriate amount of water is supplied through a discharge port 6 from a water supply pipe 5 into the hollow pipe 1 to pressurize the sand in the lower part of th pipe. The pressurized sand is discharged into the ground while pulling out the hollow pipe 1, and a quick exhaust valve 11 is opened to discharge compressed air in the hollow pipe 1 to the open air through an exhaust pipe 10. Then, a valve 9 is opened and sand is supplied from a hopper 7 into the hollow pipe 1. While penetrating the hollow pipe 1 again, the diameter of sand pile formed of pressurized sand discharged forwardly is expanded by a compactor 13. These processes are repeated to construct a sand pile up to the ground's surface at the bottom under water by using pressurized sand. |
