| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a sand removal method effective and appropriate for removing dam sediment. <P>SOLUTION: The sand removal method comprises the steps of: sinking a caisson to a lake bottom surface of a sand storage dam 10 and installing a temporary vertical shaft 14; constructing a propulsion pipe 31 by a jacking method from a distal end of a sand removal tunnel 13 to the temporary vertical shaft 14 and connecting the distal end to the caisson so as to be cut off; inserting a sand removal pipe 12 from the inside of the sand removal tunnel to the inside of the propulsion pipe; cutting off the caisson and the propulsion pipe and removing the temporary vertical shaft; floating a distal end of the sand removal pipe onto a water surface of a dam lake; connecting a sediment suction device to the distal end of the sand removal pipe on a lake surface of the dam lake and sinking it; and sucking the sediment by the sediment suction device and discharging it through the sand removal pipe 12 to the distal end of the sand removal tunnel 13. <P>COPYRIGHT: (C)2013,JPO&INPIT |
