| 摘要 |
Apparatus for driving an open-ended pipe 7, which has a driving shoe 6 at its leading end, through the ground comprises a driving member 2, 3 to which percussive driving forces are applied by a driving mechanism. Instead of fitting the part 3 of the driving member directly into the rear end of the pipe 7 as is usual an intermediate component 8 is interposed between the pipe and the part 3. The component 8 has soil outlet openings 10 and a deflector 16 to allow soil which enters the pipe 7 through the shoe 6 as driving proceeds to pass through and out of the pipe without stopping the driving. The passage of the soil through the pipe 7 is assisted by water supplied under pressure through a pipe 11 to an annular duct 12 in the shoe 6, when the water flows inwards through nozzles 13 and then rearwards through the pipe 7 carrying the soil with it.
|
