| 摘要 |
PROBLEM TO BE SOLVED: To reduce the influence of the existence of a screw jack on the pipe length as much as possible by providing a recessed part on the end faces of a spigot and a socket, and inserting both end parts of a screw jack in the recessed parts. SOLUTION: A spigot 3 is provided at one end of a pipe main body 2 formed of reinforced concrete, and a collar 4 made of steel is integrally provided on the outer peripheral surface of the pipe main body 2 including the spigot 3. The rear end part of the steel collar 4 is projected backward to construct a socket 5. recessed parts 6, 6' are provided on the end faces of the spigot 3 and the socket 5, a fitting base plate 11 is stored through a cushion material 9 in the interiors of the recessed parts 6, 6', and a frame 8 is fixed. A screw jack 16 has hexagon head bolts 17, 17' at both ends inserted in the confronting recessed parts 6, 6, with the phases of the respective recessed parts 6, 6' of the preceding propelling pipe 1 and the following propelling pipe 1 matched each other. Accordingly, the total length of the propelling pipe 1 can be made longer by the depth of the recessed part, so that the propelling man-hour can be saved and the construction can be reduced. |
