BORING METHOD IN SHIELD MACHINE AND SHIELD MACHINE

摘要

PROBLEM TO BE SOLVED: To make possible building of a covering body easily and in a short time in building covering bodies sequentially while boring small tunnels. SOLUTION: A shield body 13 rectangular in cross section, a cutter head which is mounted to the front end of the shield body 13 in a rotatable manner and is intended for boring a rectangular hole, and a sheet pile driving unit 16 which drives sheet piles in the external face of a clearance with an existing covering section 1B, are provided. The sheet pile driving unit 16 is composed of a sheet pile retaining unit arranged on the shield body 13 side, a sheet pile guiding unit 22 arranged in the internal face of the side of the shield body 13, and a sheet pile extruding unit 23 which extrudes a sheet pile guided and supported in a prescribed direction toward the external face of an existing covering section 1A from the inside of the shield body 13.