ADVANCING METHOD FOR SHIELD MACHINE BY WATER SEALING AND PRESSURE APPLICATION IN ARRIVAL SHAFT

摘要

PURPOSE: To prevent excavated earth and sand from flowing out when a shield machine arrives at and drives to an arrival shaft. ;CONSTITUTION: When a shield machine 1 arrives at an arrival shaft A, a mirror portion 3a is bored on the wall of the shaft. A water stop steel plate ring 4 and an entrance rubber gasket 5 are mounted to the peripheral edged entrance of the mirror portion 3a. A preliminarily made arrival box-shaped body 6, which is slightly larger than the shield machine 1 and provides a water injection pipe 7 and a wire rope insertion pipe 8, is tightly connected to the gasket 5. Before the shield machine 1 is shield-propelled, the box-shaped body 6 is water- sealed and pressurized and the shield machine 1 is launched. At the same time, a wire rope 9 inserted into the wire rope insertion pipe 8 is tensed. After the gasket 5 is pressure-welded to the outer periphery of a segment to be connected to the shield machine 1 and water-stopped, the shield machine 1 and the arrival box-shaped body 6 are pulled up and removed.;COPYRIGHT: (C)1994,JPO&Japio