| 摘要 |
PROBLEM TO BE SOLVED: To prevent spreading of looseness and contrive improvement of working efficiency in an interior ground part by excavating ground by an excavator, stopping the excavator when the looseness and void of the ground are detected, injecting a chemical into the void by an air spray, and filling the void with the chemical. SOLUTION: A ground S is bored by a tunnel boring machine 1, after the looseness and void of the ground S are detected from the machine data of the increase or the like of cutter torque and the in-adit observation or the like from the gap of the slit or the like of a cutter head, the tunnel boring machine 1 is stopped, and the position and size of the void are confirmed from the gap of the slit or the like of the cutter head. Next, a heat resistant polyvinyl chloride pipe 2 is inserted in the void R produced by collapse, a chemical is injected by an air mixing method from a nozzle, the void R is filled, and spreading of the void (looseness) is prevented. Thereby it can be easily and inexpensively executed as compared with the conventional method. |
