SHIELD BORING MACHINE CAPABLE OF MAKING BRANCH START AND BRANCH SHIELD BORING METHOD

摘要

PROBLEM TO BE SOLVED: To enable the main track tunnel to be bored in a curved shape by a shield boring machine and, at the same time, after the shield boring machine has reached a branch spot, to open a starting opening without propelling the internal drum forming the starting opening therein to surely make branch start of a branch shield boring machine from the starting opening in the predeterminded starting direction in a branch spot.;SOLUTION: The shield boring machine 1A is equipped with: cut-off seals 44 and 45 for stopping water between the external drum 5 and the internal drum 6 around both ends in front and behind of the internal drum 6; a drum connecting mechanism 46 for integrally and detachably connecting the external drum 5 to the internal drum 6 in a state to fit the internal drum 6 to the external drum 5 from the inside; and a plurality of propulsive jacks 62 for opening the starting opening 50 by propelling the external drum 5 together with the front drum 2 to the internal drum 6 in a state disconnected from the drum connecting mechanism 46.;COPYRIGHT: (C)2004,JPO