To provide structure to minimize a tunnel diameter and simultaneously facilitate the passage of a burying piping through a tunnel, in a nonescavating method.

A burying piping made of plastic comprises a joint member 1A comprising a body 5A made of thermoplastic resin consisting of a first taper inner circumferential surface 3A spreading from an internal central part 6A toward one end side and a second taper inner circumferential surface 4A spreading from the central part 6A toward the other end side, and a heat generating body 2A buried in the vicinity of the first and second taper inner circumferential surfaces; a first plastic pipe 10A formed of thermoplastic resin having a taper outer peripheral surface 11A coinciding with the surface 3A of the joint member 1A; and a second plastic pipe 20A formed of thermoplastic resin forming a taper outer peripheral surface 21A coinciding with the surface 4A of the joint member. When the first and second surfaces 3A and 4A of the joint member 1A and the first and second plastic pipes 10A and 20A are respectively fused and formed integrally through heating of a heat generating body, the outer peripheral surface of the joint member 1A and the outer peripheral surfaces of the first and second plastic pipes 10A and 20A are positioned approximately flush with each other.