| 摘要 |
PURPOSE:To enable execution of various ground improving methods, by a method wherein an excavation pipe holding rotary device is movably supported, a chuck is rotatably provided, and a rotary angle setting means for an excavation pipe is mounted. CONSTITUTION:An excavation pipe holding rotary device 6 is lifted along a leader 3 by means of a wire 7, and with a rotary driving means 10 driven, a chuk 9 is turned. A bit 16 is moved downward, and a pilot hole 26, serving as the locus of the bit 16, ie excavated in earth. A cylindrical cavity 32 is formed in a ground by means of ultra-high pressure water 29, and a ground improving agent is injected by a high pressure through a nozzle 17 to fill the cavity 32 with the ground improving agent to build a solid artificial ground. This enables improvement of a ground through a single ground improving device, which is sufficiently durable even against a violent handling manner. |
