| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a crushing cutter statically crushing an existing pipe without depending upon an impulse, etc., while being able to lay a new pipe by weak driving force and a construction method using the cutter. SOLUTION: The crushing cutter has a rotatable crushing blade 13, in which a section in the vicinity of a front end is supported pivotally, and a tapered section 27 abutted against the free end of the crushing blade 13 while having a piston 11 capable of being forwarded and retreated and a cutter body 26, in which an outside diameter is increased gradually from a section in the vicinity of the free end of the crushing blade 13. In the pipe jacking method, a hydraulic jack 8 for tension is installed to an arrival shaft 2 and a shield jack 4 to a departure shaft 1 respectively, and the expansion type crushing cutter 9 is pulled by the hydraulic jack 8 for tension while a new pipe 10 to be laid by the shield jack is propelled so as to be connected to the expansion type crushing cutter 9 in an existing pipe 3.</p> |
