| 摘要 |
PROBLEM TO BE SOLVED: To improve excavation efficiency and improve posture control by performing the excavation of a large section tunnel with a heading face by a main shield body only by a rotary cutter head. SOLUTION: In a separation type shield machine in which a sub shield body 51 is started from a main shield body 1 to continuously excavate a single track from a widened tunnel having a large heading face, a plurality of subshield bodies 51 are held in the main shield body 1 to separately start forward and a rotary sub cutter head 52 is provided in front of the sub shield body 51. A rotary chief cutter head 2 excavating a part except the excavating part of the sub cutter head 52 is shifted back to the sub cutter head 52 and arranged in the main shield body 51. A notch 2a allowing the sub shield body 51 to pass through when starting is formed in the main cutter head 2. COPYRIGHT: (C)2004,JPO&NCIPI |
