PROPULSIVE PIPE FOR METHOD OF PROPULSIVE CONSTRUCTION

PROBLEM TO BE SOLVED: To bend a propulsive pipe in a curvature radius smaller than conventional devices by interposing flexible sections having a sherical bearing structure, in which an inner cylinder, in which an outer circumferential surface is formed in a spherical surface, is fitted onto the outer cylinder, among a plurality of rigid short pipe sections and connecting the short pipe sections. SOLUTION: A pushing member 3 for propulsion pushing a propulsive pipe 2, in which a propulsive head 1 is installed at a front end, is mounted into an execution pit, and the propulsive pipe 2 is held so as not to be bent by a guide member 4 and propelled. Bendable flexible sections 2B are interposed among a plurality of rigid short pipe sections 2A respectively in the propulsive pipe 2, and connected and formed only in a required length. The flexible sections 2B are formed in spherical bearing structure by inner pipes 9, in which outer circumferential surfaces are formed in spherical surfaces, and outer pipes 10, to which the inner pipes 9 are slidably fitted externally and which receive the inner pipes 9, and the rigid short pipe sections 2A are coupled mutually in a bendable manner at 3 deg.-10 deg. so as not to be brought near and separated. According to such formation, the propulsive pipe 2 is bent by a curvature radius smaller than conventional devices. A pull-in pipe for burying is connected to the propulsive head 1, and pulled in.