| 摘要 |
PURPOSE:To control the direction of a tunnel excavator easily and positively. CONSTITUTION:A plurality of direction control jacks 6 are borne by moving trestles 8 capable of being moved in the direction of a tunnel axis, and disposed at regular intervals in a shield by jack bearing members 9 fixed and borne into a shield body l. The rams 7 of the direction control Jacks 6 are projected from the outer circumferential surface of the shield body 1, pushing force pushing a tunnel pit wall by the rams 7 is adjusted, and the position of the shield body 1 is adjusted in a surface rectangular in the direction of tunnel propulsion. The moving trestles 8 are moved on the jack bearing members 9 through bearing pedestals 15 so that the position of the tunnel pit wall pushed by the rams 7 of the direction control jacks 6 is not shifted with the propulsion operation of the shield body 1. Accordingly, a position after the adjustment of the shield body 1 is held. |
