Segments are linked in the circumferential direction to assemble a pipe unit. A link bolt is used to link the segments of the pipe unit in the longitudinal direction to assemble a rehabilitation pipe inside an existing pipe. An elastically deformable hollow cylindrical member having a tongue is attached to the link bolt between the inner plates. The outer diameter of the cylindrical member is larger than the insertion hole of the inner plate through which the link bolt can pass. This allows the link bolt to be prevented from falling out of the segment when the link bolt moves in the longitudinal direction due to gravity. When a force is applied to the tongue from below, the cylindrical member is elastically deformed and can be removed from the link bolt.