| 摘要 |
PROBLEM TO BE SOLVED: To provide an excavating mechanism capable of excavating an underground space economically in a short construction period even when the construction length of a rectangular roof is limited.SOLUTION: This excavating mechanism 2 including a main section excavator 15 which has a projection 47 at the latter half of the body, a propulsion jack 33 installed at the rear of the main section excavator 15, a rectangular roof excavator 13 installed in front of the projection 47, and the like, is installed in a vertical shaft 1, and a cover plate 25 is attached to near the rear end 23 of the rectangular roof excavator 13. Next, while advancing the rectangular roof excavator 13 for boring independently of the main section excavator 15 using a propulsion jack 21 for a rectangular roof installed inside the projection 47, the rectangular roof 27 is installed at the rear of the rectangular roof excavator 13. While advancing the main section excavator 15 using the propulsion jack 13 for boring, the rectangular roof 27 inside the projection 47 is recovered and dismounted, and a steel shell 37 is installed between the main section excavator 15 and the propulsion jack 33. |
