| 摘要 |
<p>PURPOSE:To unwind the surplus part of the flexible inner pipe following uneven settlement of a soft ground and to prevent the occurrence of the breakage accident of a piping by a method wherein a flexible inner pipe is inserted in a sheath pipe to form a double pipe and the double pipe is buried in a soft ground in a state winding the surplus part of the flexible inner pipe. CONSTITUTION:A flexible inner pipe 2 having length longer than that of a sheath pipe is inserted in a sheath pipe 1 being a corrugated pipe to form a double pipe 6. The two ends of the sheath pipe 1 are fixed to the side walls of manholes 3A and 3B and the two ends of the flexible inner pipe 2 are connected to respective valves 5 and the surplus part of the flexible pipe 2 is wound around a winder 4. Thereafter, the double pipe 6 is buried in a soft ground. In which case, when uneven settlement occurs to a soft ground, the sheath pipe 1 is stretched and the surplus part of the flexible inner pipe 2 is unwound from the winder 4 and delivered in the sheath pipe 1. This method absorbs a force owing to uneven settlement and prevents an abnormal force from being generated at the flexible pipe 2.</p> |
