| 摘要 |
PURPOSE:To inject a group in every direction along circumferential line during the grout injection work by a method in which the injecting directions of fluid is exactly selected for excavation and group injection by forming a slit with the rise of the internal pressures in the part corresponding to the small hole of an outer tube. CONSTITUTION:When passing pressure water for drilling through the inner tube of a drilling and group injection tube 1, a drilling water valve 7 is pushed down when the pressure of the pressure water exceeds the pushing force of a spring 6, and the pressure water is jetted toward the lower part in the axial direction of the tube 1. Accordingly, when the tube 1 is penetrated underground while being turned, drilling is performed. Then, when charging a hardening agent solution into the outer tube 3, the solution pushes down a slide stopper 5, reaches an opened part 11 through a spiral flow path provided in the slide stopper 5, is mixed with the main agent solution there, and then directed to a trap chamber 12. Whereupon, the outside wall 13 of the trap chamber 12 is opened in sliding manner by the rise of the internal pressure, and the mixture of main agent and hardening agent from the slit 14 is injected into the ground. |
