| 摘要 |
PROBLEM TO BE SOLVED: To efficiently execute a tunnel having an acute curve in a bedrock by providing a soil-collecting device radially projecting when protruding an overbreak device, at the outer peripheral part of a rotatable cutter head. SOLUTION: An overbreak device composed of many disc cutters 6 is equipped in a rotatable cutter head 5. A soil-collecting device 10 radially projecting when protruding the disc cutter 6, is provided at the outer peripheral part of the cutter head 5, in this tunnel boring machine. In this way, excavated soil, rock, muck can be securely collected into the cutter head 5 in the overbreak work, and hence, a tunnel with an acute curve in a bedrock can be efficiently excvated. Further, the retractable length of the soil-collecting device 10 can be made adjustable and it is preferable that the projecting and contracting operation can be remotely controlled. |
