Abstract: A trenchless mechanical lining apparatus for continuous repair of underground pipes and culverts, and a method of installation. The apparatus includes a plurality of core elements, each having a first end and a second end, the second end being an enlarged receiving end configured to receive a first end of a successive one of the core elements; a sealant to secure a first end of a first core element to a second end of a second core element; the core elements having lengths configured to span a length of a repair site; and a system for applying longitudinal pressure to secure the first core element to the second core element, the system including a cable and securing device, the latter configured to be attached to an end of an enlarged receiving end, and a pressure-applying device for forcing the first and second core elements together.