| 摘要 |
PROBLEM TO BE SOLVED: To provide a propulsion machine which contacts the wall of excavated bore to prevent the occurrence of rolling when a layer of rock mass is excavated using a semi-shield tunneling method and can be advanced along the wall of the bore by a thrust imparted by a main propulsion device. SOLUTION: A tracking members 12 each having a contact member 13 for contact with the wall B of a bore are provided respectively at horizontally, diametrically opposed positions on the outer periphery of a tail shield 2 constituting the propulsion machine A. A port 14a of a hydraulic cylinder 12a of one of the members 12 and a port 14a of a hydraulic cylinder 12a of the other member 12 are interconnected by a pipe 15e, and a port 14b of the cylinder 12a of one of the member 12 and a port 14b of the cylinder 12a of the other member 12 are interconnected by a pipe 15f, whereby pressure oil having a pressure set beforehand by a pressure reducing valve 15b is supplied through the pipes 15e and 15f. If the pressure oil is supplied, each of the contact members 13 protrudes and contacts the wall surface B of the bore to transmit rolling forces against the machine A generated by the rotation of a cutter head to the wall surface B, so that the machine A is supported. |
