| 摘要 |
PROBLEM TO BE SOLVED: To improve work efficiency by reducing stage replacement work when moving forms in accordance with a method of construction for improving the quality of lining concrete wall within the tunnel by prolonging a curing term of the lining concrete wall within the tunnel by alternately using a plurality of forms.SOLUTION: A plurality of installation areas to install therein forms 2, 3 which may take diameter enlarged states W2, W3 and a diameter reduced state S2 are arranged side by side with each other in a length direction X within a tunnel 1. The plurality of installation areas include a front area P1 at a side of an installation progressing direction XF, a rear area Q1 at a side of an opposite direction XB to the installation progressing direction XF, and an intermediate area R1 between the front area P1 and the rear area Q1. When performing installation successively from the form 2 installed in the rear area Q1, the preceding form 2 brought into the diameter reduced state S2 can be moved to the front area P1 through the inside of the following forms 3 in the diameter enlarged states W2, W3. A movable stage 6 of a support stand 4 has such a length as to support the forms 2, 3, thereby moving from a retracting position 4B over the rear area Q1 and the intermediate area R1 to a forward position 4F over the intermediate area R1 and the front area P1. A transfer stage 7 of the support stand 4 for supporting the form 2 in the diameter reduced state S2 is capable of reciprocating in the length direction X on the movable stage 6. Thus, work efficiency is improved by reducing stage replacement work when moving the forms 2, 3. |
