| 摘要 |
PROBLEM TO BE SOLVED: To provide efficient propulsion by preventing closure or the like caused by clinging of clay even in a clay layer during muddy water propulsion work. SOLUTION: In this method for propelling a muddy water excavator 12 in a clay layer, a mud feed pipe and a mud discharge pipe are passed through a propulsion pipe 24 via a vertical shaft from a muddy water disposal device 1 installed around the vertical shaft, and are connected to an excavator 12, so that as the natural ground is held by muddy water fed from the mud feed pipe 11, mud excavated by the end of the excavator 12 is made to flow back from the mud discharge pipe 13 into the muddy water disposal device 1, together with muddy water. An injection device 6 for injecting coarse grains 21 is installed at a takeout opening in the adjusting vessel 3 of the muddy water disposal device 1 installed around the vertical shaft, and the coarse grains 21 and the muddy water are injected at the end of the muddy water excavator 12 through the mud feed pipe 11 via a mud feed pump 10 from the takeout opening of the adjusting vessel 3. Clay cut and clinging to a face plate and the inside of a chamber is thereby scraped off and is made to flow back into the muddy water disposal device 1 through the mud discharge pipe 13, together with the coarse grains 21 and the muddy water. The injection device 6 comprises a hopper capable of retaining a predetermined amount of coarse grains 21 in its upper portion and a connecting pipe extending through the adjusting vessel 3 of the muddy water disposal device 1 from the underside of the hopper and connected to a suction opening leading to the mud feed pump 10. |
