ECCENTRIC STARTING CONSTRUCTION METHOD OF SLAVE SHIELD MACHINE IN MASTER/SLAVE SHIELD EXCAVATOR

摘要

PROBLEM TO BE SOLVED: To enable a small-bore tunnel to be constructed so as to make the center line of it eccentric relative to the center line of a large-bore tunnel, and facilitate drilling of a tunnel according to the use, by bendingly executing a shield work so that the center line of a slave shield machine is aligned with the center line of the small-bore tunnel, before reaching the starting point of the slave shield machine. ;SOLUTION: A master shield machine 1 and a slave shield machine 2 are integratedly shielded, and a large-bore tunnel 17 is drilled along the center line C1 up to a little this side of the starting point of the slave shield machine 2. Next the shield machines are turned to the direction making a front shield eccentric relative to a rear shield, and after shielding by a fixed distance, they are turned so that the front shield is in the opposite direction, the center line C2 of the slave shield machine 2 is aligned with the center line C1 of the master/slave shield excavator, and then the slave machine 2 is started so as to drill a small-bore tunnel 18. Hereby a desired tunnel according to the utilization such as piping facilities of sewerage or a station of the subway can be drilled extremely easily.;COPYRIGHT: (C)1998,JPO