| 摘要 |
<p>PROBLEM TO BE SOLVED: To lay a pipeline having earthquake-resistant pipe joints, using a jacking method. SOLUTION: The pipe joint has a spigot inserted into a socket while leaving a pushing space S between the tip of the spigot 2 and the rear end of the socket 3. A cylindrical element 10, having an inside diameter smaller than the outside diameter of a columnar element 9 having its tip 9a pointed to the open end 3b of the socket and having its rear end 9b secured to the outer surface of the spigot 2, is positioned a the tip of the columnar element 9 in such a way that the open side of the cylindrical element 10 is brought into contact with the outer peripheral surface of the tip of the columnar element 9 while the other end of the cylindrical element 10 is brought into contact with the open end face of the socket, on a coaxial line. The distance from the tip of the columnar element 9 which makes contact with the cylindrical element 10 to the other end of the cylindrical element 10 is made longer than the pushing space S and the strength of the cylindrical element 10 is such that while the cylindrical element is not enlarged and deformed by a reduced-diameter part at the tip of the cylindrical element 9 in the presence of a normal jacking force, it is enlarged and deformed by the tip 9a of the cylindrical element 9 in the presence of a great axial external force, as in an earthquake.</p> |
