| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a construction method of a utility tunnel from an existing side ditch for drainage, without requiring complicated maintenance work for the drainage after construction. <P>SOLUTION: A construction method of a utility tunnel from an existing side ditch 1 for drainage comprises the steps of: (a1) fixing a supporting member 21 on a midway part of the right and left sides of the side ditch 1 in vertical direction, (b1) storing cables 5 on the bottom of the side ditch 1, and (c1) placing a bottom plate member 12 to be accommodated in the side ditch 1 on the supporting member 21 to form a new drainage 17 in the upper portion of the side ditch 1. <P>COPYRIGHT: (C)2012,JPO&INPIT |
