| 摘要 |
PROBLEM TO BE SOLVED: To easily penetrate an outer pipe, by reducing penetration resistance of an excavating head, by injecting a high pressure fluid (for example, high pressure water) into a tip part of the excavating head of the outer pipe from a high pressure fluid injection nozzle of an inner pipe, when penetrating the inner pipe and the outer pipe into the ground; and to uniformly knead a ground improving material and the ground soil in the excavating head, by its rebounding force, by injecting a ground hardening material under high pressure independently or together with air and water, so as to strike on an inner surface of the excavating head of the outer pipe from the high pressure fluid injection nozzle of the inner pipe, when extracting the inner pipe and the outer pipe. SOLUTION: A rotational driving device 4 is arranged in an upper end part. The inner pipe 1 provided with the outward high pressure fluid injection nozzle 8 is arranged in a lower end part. A rotational driving device 6 is arranged in the upper end part, and is vertically movably inserted into the outer pipe 2 for projecting the large diameter cylindrical excavating head 10 on the lower end, and the vertical directional relative positional relationship between the high pressure fluid injection nozzle 8 and the excavating head 10 is freely adjusted. The high pressure fluid injected from the high pressure fluid injection nozzle 8 is struck on an inner surface of the excavating head 10, and the ground improving material and the ground soil are uniformly kneaded by the rebounding force. 7 is a cylinder device arranged between respective upper end parts of the inner pipe 1 and the outer pipe 2. 13 is a soil mass crushing piano wire tensioned inside the excavating head 10. COPYRIGHT: (C)2005,JPO&NCIPI
|
