Hole drilling rig and its excavation manner and welding ground anchor construction manner null for welding ground anchor

摘要

PROBLEM TO BE SOLVED: To easily and rationally form a hole and an expanding part. ;SOLUTION: A pipe 6 is installed on a support member 2, and an excavating screw 5 is inserted so as to be drivable in rotation in the pipe 6 and to be movable in the lengthwise direction of this pipe 6. A tip part of the screw 5 projects more than the tip 6a of the pipe 6. An injection nozzle 8 injects high pressure water supplied through the inside of the screw 5 in the horizontal direction. An extruding device 10 is extended, and the screw 5 is moved to a condition shown in (b) from a condition shown in (a), and water is injected outside the pipe 6 from the injection nozzle 8, and an expanding part W is formed in the soil E.;COPYRIGHT: (C)1997,JPO