PROBLEM TO BE SOLVED: To provide a pre-filling replacement structure in a shield break part which has less possibility that brings collapse of natural ground or ground subsidence as comparared with conventional cases. SOLUTION: This pre-filling displacement structure in a shield outbreak part is constituted of a shield mashine 10, segment rings for a curved line, segment rings provided with shelter bags, segment rings for a straight line, a filling structure charging a viscous fluid filler 3 in a gap between the shield machine 10 and a hole 5, an injection structure for injecting a backfill material 4 in a gap between the segment for a curved line and the hole 5, and a control structure controlling the filling structure. In the outbreak part 5a, after the filler 3 has been filled in a pressurized condition in the injection hole 11c positioned immediately after the excavating structure has been operated and the injection hole of the segment ring 21x for a curved line, it is replaced with the backfill material 4 in between the segment rings 22x, 22y provided with shelter bags. Therefore, collapse of natural ground and ground subsidence become hard to arise even in the outbreak part as compared with conventional cases and hence, ground deformation is also hard to arise.
展开▼
