| 摘要 |
PROBLEM TO BE SOLVED: To provide a widening type shield boring machine capable of stably excavating a widening cross section without causing any increase of propulsion resistance while preventing the collapse of a bedrock. SOLUTION: The widening type shield boring machine includes the first cutter head placed in the front section of a shield body 1 to excavate a standard cross section, a widening opening section 12 formed in a skin plate 1a of the shield body 1, a cutter storage chamber 13 formed by communicating with the widening opening section 12, an in and out block 14 placed in the cutter storage chamber 13 enabling it to come in and out to the outside through the widening opening section 12 to have the second cutter head 11, a cutter coming in and out device 15 enabling the in and out block 14 to come in and out and an opening and closing shutter device 16 having an opening and closing door 27 enabling the widening opening section 12 to freely open and close. COPYRIGHT: (C)2006,JPO&NCIPI |
