CUT-OFF STRUCTURE OF SHIELD MACHINE ARRIVAL SHAFT AND ARRIVAL METHOD

摘要

PROBLEM TO BE SOLVED: To ensure cut-off of an arrival pit mouth through a simple structure.;SOLUTION: The cut-off structure 1 for arrival of a shield machine 2 to a shaft 3 cuttable thereby comprises a ring-like expansible cut-off member 5 provided inside the shaft 3, the inner circumference of which contacts with the outer circumferential surface of the shield machine 2 or a segment 13 when expanded to form a cut-off surface; a consolidation material 6 provided on the inside of the shaft 3 in a predetermined thickness so as to stow the cut-off member 5 and cuttable by the shield machine 2; and a cavity part 7 forming a substantially expansion area for the cut-off member 5 within the consolidation material 6. A proper number of washing means 8 for injecting water at high pressure toward the radial outside are provided in predetermined positions of the circumferential part 2a of a cutter 2B of the shield machine 2.;COPYRIGHT: (C)2008,JPO&INPIT