Pipe rehabilitation method

A pipe rehabilitation method in which segments each including an inner surface plate, side plates that are provided upright on both sides extending in the circumferential direction of the inner surface plate and have insertion holes formed thereon, and inner plates that are provided upright on the upper surface of the inner surface plate inside the side plates and have insertion holes formed thereon are coupled in the longitudinal direction while the side plates of the segments are butted against each other to install a rehabilitation pipe inside an existing pipe, the method comprising:

• preparing a coupler having a plurality of claws that are radially elastically deformable and long so as to protrude through the insertion holes of the side plates of the butted segments;
• fixing the coupler to one segment so that the claws pass through the insertion hole of the side plate of the one segment and protrude to the outside;
• inserting the claws of the coupler projecting from the side plate of the one segment into the insertion hole of the side plate of the other segment that is butted against the one segment, the side plates of both the segments being butted together to protrude the claws of the coupler into the other segment;
• elastically deforming the claws of the coupler protruding into the other segment to expand the claws in diameter;
• and
• pressing the side plate of the other segment against the side plate of the one segment by the claws of the coupler whose diameter has been expanded to clamp both the side plates and couple the one and the other segments in the longitudinal direction,
• wherein in expanding the diameter of the claws, a diameter expansion pin is used that is inserted between the claws of the coupler and elastically deforms the claws.