| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a branch portion structure for underground multi-purpose wire ducts wherein only the connections of the wire ducts with each other are necessary without requiring any cast-in-situ concrete work. SOLUTION: A branch portion structure for underground multi-purpose wire ducts has cylindrical precast concrete body blocks 1 with a predetermined length in each of which a hole 3 for inserting wires thereinto and checking the wires therethrough is formed in its top plate portion 2 and knockout portions 5 forming through holes for drawing out the wires therefrom are formed in its both sidewalls 4. Further, to both end opening portions of the connected body blocks 1, box type end portion blocks 6 made of precast concrete are coupled respectively. Moreover, in each end portion block 6, opening portions 9 or knockout portions 10 for drawing out the wires therefrom which communicated with the opening portion of the body block 1 are so formed that underground multi- purpose wire ducts 11 can be inserted into the opening portions 9 or butted against the knockout portions 10.</p> |
