DIAMETER REDUCTION DEVICE OF SEGMENT FOR TUNNEL, TUNNEL LINING STRUCTURE AND FREEZING EXPANSION COUNTERMEASURE METHOD

摘要

PROBLEM TO BE SOLVED: To provide a diameter reduction device of a segment for a tunnel, a tunnel lining structure and a freezing expansion countermeasure method, capable of further surely reducing freezing expansion pressure acting on the segment, capable of shortening a construction period and capable of reducing cost.SOLUTION: A diameter reduction device 100 is provided for diametrically reducing a lining diameter D of a segment 12 for constituting a tunnel lining by mutually joining by being juxtaposed in the circumferential direction S and the axial direction of a tunnel inner surface 10, and is provided with pressure adjustment means 22 provided between joints 16 of the segment 12 adjacent in the circumferential direction S and adjusting a diameter reduction quantity of the lining diameter D by changing a separate distance (d) between the joints 16 in response to earth water pressure acting on the segment 12 from the peripheral ground G.SELECTED DRAWING: Figure 1