| 摘要 |
PURPOSE:To exactly improve the ground by a method in which a high-pressure fluid is jetted from a tube penetrated into the ground to loosen the ground and at the same time or thereafter, a quick-setting chemical grout having a gel time of within a specific time period is injected into the loosened portion of the ground. CONSTITUTION:The surface layer of the ground is excavated by giving a turning force and a penetrating force to a rod 1 while jetting a boring water W' from a nozzle 26 in a state of being attached with a sub-drill 14. The sub-drill 14 is removed, and excavation is further made to a given depth only by boring force of the water W' from the nozzle 38 and under the weight of the rod 1. The rod 1 is turned and at the same time high-pressure water W is jetted from the nozzle 32 to form loosened zone Z1. Both liquids A and B of a chemical grout are divertedly flowed and mixed together in front of the nozzle 26 and then injected into the surrounding ground. The chemical grout is injected while pulling up the rod 1 to form a continuously solidified zone Z2 |
