| 摘要 |
PURPOSE:To prevent the pollution of sea area by avoiding the leak of compressed air in the construction work of sand piles by a method in which sand piles are constructed while keeping the sand in the upper part of a hollow tube for constructing the sand piles in a natural moisture content ratio and also the sand in the lower part of the hollow tube in a moistened state. CONSTITUTION:After a hollow tube 1 is penetrated to a given depth from the bottom under water, and then sand 13 is charged from a hopper 2 into the hollow tube 1. An exhaust pipe 7 is closed, compressed air is sent into the hollow tube 1 from a supply tube 6, a valve 4 is closed, and pressure water is supplied from a supply tube 9. Then, water is supplied from a nozzle 10 to the sand 13. After the hollow tube 1 is pulled out by an adequate distance, the exhaust pipe 7 is opened to discharge compressed air, and when the hollow tube 1 reaches ordinary pressure, the valve 4 is opened by its own weight. While supplying sand from the hopper 2, the hollow tube 1 is repenetrated, and the moistened sand 13' previously charged is compacted to expand its diameter. These processes are repeated to construct a sand pile. |
