| 摘要 |
PURPOSE:To raise the efficiency of operations by a method in which a double tube consisting of an inner tube and a group tube is inserted into a seamed tube with discharge ports, and an elastic material is covered on the double tube to for a communication hole on the double tube covered with the elastic material. CONSTITUTION:A seamed tube 2 whose tip is closed is set into the ground, a packer is attached to the basal end side of the tube 2, and a grout tube 3 with an inner tube 4 is inserted into the tube 2. A packing 5 is expanded by relatively moving the tubes 3 and 4 in the tube 2, and a grout of low pressures is packed from the basal ends of the tubes 3 and 4. Whereupon, the grout is jetted from the discharge ports 22 because the back flow of the grout is prevented. The tubes 3 and 4 are then drawn out, cement mortar is packed into the tube 2, and the tube 2 is advanced toward the excavating direction of tunnel in a state of being buried. |
