DOUBLE-PIPE AND DOUBLE-PACKER CONSTRUCTION METHOD

摘要

PROBLEM TO BE SOLVED: To practice a double-pipe and double-packer method without a delay of a construction period.;SOLUTION: A plurality of injection holes 1a are provided on a peripheral wall, and an inner rod, which is fitted with an excavating bit transferring a striking force and a rotational force, applied from a single-pipe excavator, to a ring bit 1b, is inserted into a casing 1, the leading end of which is fitted with the ring bit 1b, so that a hole can be bored in natural ground G. After the inner rod and the excavating bit are pulled out from the casing 1, a sleeve pipe 3, wherein an ejection hole 3a is formed, is inserted into the casing 1, and a sealing material 6 is infilled into a gap between the casing 1 and the sleeve pipe 3. An injection pipe 4, which is equipped with a pair of packers 4b and 4b and a jet hole 4a provided between the packers 4b and 4b, is inserted into the sleeve pipe 3. In the state of the installation of the casing 1 in the natural ground G, grout 5 is injected into the natural ground G from the injection hole 1a via the jet hole 4a and an ejection hole 3a.;COPYRIGHT: (C)2007,JPO&INPIT