While digging Shank doing the tunnel

摘要

PPROBLEM TO BE SOLVED: To provide a cast-in-place lining shield method which contributes to formation of a thin thickness of a lining concrete layer without causing degradation of a concrete force-feeding ability and without clogging a pipe line of a concrete placing pipe, and to provide a shield machine. PSOLUTION: According to the cast-in-place lining shield method, an inner form 4 is set along a tunnel internal peripheral surface 10 by a rear end of a skin plate 2 of the shield machine, and an end portion of a concrete placement space 10 defined by the tunnel internal peripheral surface and the inner form is blocked with an end form 5 arranged between the skin plate and the inner form, and movable in forward and backward directions. The end form 5 has formed therein an elliptic concrete placing hole 9 that extends along a circumferential direction thereof, and the concrete placing pipe 11 having a pipe line cross sectional area almost equal to an opening cross sectional area of the placing hole, is connected to the placing hole, followed by force-feeding and placing the concrete from a concrete pump through the placing pipe. The concrete C filled in the concrete placement space is pressurized to a predetermined value by the end form. PCOPYRIGHT: (C)2009,JPO&INPIT