Promotion boxes, and tunnels and large cross-section tunnel, tunnels and large cross-section tunnel method of construction

摘要

PPROBLEM TO BE SOLVED: To provide a jacking box for economically constructing a tunnel composed of a linear section and a curved section formed of a plurality of radii of curvature, and to provide the tunnel and a large cross section tunnel, and a construction method of the tunnel and large cross section tunnel. PSOLUTION: The jacking box 1 having a through hole 12 is rectangular or square from the front view when viewed from an extended direction of the through hole 12, and hexagonal from the side view orthogonal to the front view. The hexagonal shape is composed of an upper side 13a, a lower side 13b parallel or almost parallel with the upper side 13a, and two right and left sides 13c, 13c formed of two bent side parts 13c1, 13c2. PCOPYRIGHT: (C)2008,JPO&INPIT