Excavation method without drilling holes inner wall collapse

摘要

PROBLEM TO BE SOLVED: To prevent collapse of an excavation hole inner face and lessen friction between a pipe and the excavation hole inner face by providing a discharge outlet projecting gel on the outer periphery of the rotation body of the cutting blade of an excavator edge, rotating the rotation body of the cutting blade, discharging gel from the discharge outlet to the outside and performing excavation while gel solution is filled into a gap between the inner face of an excavation hole and a rearward connecting pipe. ;SOLUTION: A liquid discharge outlet 4 is provided on the outer periphery of the rotation body 1 of a cutting blade 2 to excavate an excavation hole 14 while rock is crushed, and first solution 6 and second solution 7 are discharged through passages 9, 10 during excavation. The liquid discharge outlet 4 is provided to be recessed on the outer peripheral face, the first solution 6 and the second solution 7 are mixed in the recessed part, and gel solution 5 changed into gel is discharged. Since the outlet 4 is rotated along the inner face of an excavation opening 14 together with the rotation body 1, the gel solution 5 is filled into a gap between a pipe 3 and the inner face of the excavation opening 14 without any gap. Thus, collapse of the inner face of the excavation hole 14 is prevented, and friction between the pipe 3 and the inner face of the excavation hole 14 can be lessened.;COPYRIGHT: (C)1998,JPO