Abstract: A method for preventing water leakage into and out from a pipeline utilizes an injection material and a liner. The injection material exhibits fluidity and hardenability. The liner includes an elastically deformable sleeve having an outer diameter smaller than the inner diameter of the pipe and a plurality of elastically deformable and successively circumferentially extending projection portions formed at axial intervals on the circumferential surface of the sleeve; a sheetlike base placed inside the sleeve in a radially expandable, wound cylindrical form; fixing means for maintaining the base in a substantially cylindrical form when the base is radially expanded inside the sleeve; and check valve means defined by the sleeve and the base when the base is radially expanded. The check valve means permits the injection material to flow from the inside of the base into the space between the projection portions in the axial direction.

Abstract: A liner for pipeline repair is provided that includes an elastically deformable sleeve having impermeability, a base having a sheet-like base portion disposed inside the sleeve, wound into a cylindrical form, and expandable radially and fixing means disposed in the base for maintaining the base portion in a subtantially cylindrical form when the base portion is expanded radially within the sleeve. The liner is used for preventing the outflow of water from a pipeline such as a sewer pipe and/or the inflow of water into the pipeline.