| 摘要 |
PROBLEM TO BE SOLVED: To provide a shield machine cutter bit replacement method capable of repeatedly performing a cutter bit replacement merely by an underground work and a shield machine cutter retracting mechanism. SOLUTION: A solidifying agent 28 is filled between a heading 8 and a partition wall 7 partitioning the inside of a shield frame 2, the partition wall 7 is moved backward into the shield frame 2 while a soil pressure of the heading 8 is being held by the filled pressure of the solidifying agent 28, and a cut-off wall 32 due to solidification of solidifying agent 28 is formed in the shield frame 2 positioned ahead of a cutter 9 while the cutter 9 mounted in the partition wall 7 is being extracted into the shield frame 2. Then, a cutter bit 13 is replaced with a new one in the shield frame 2 positioned behind the cut-off wall 32, the cut-off wall 32 is excavated by moving forward the partition wall 7 while the cutter 9 is being operated, and the cutter 9 and partition wall 7 are returned back to the original positions. |
