Patent ID: 8613567

Claim:
A tunnel liner comprising a plurality of curved steel rib sections joined together end to end with a gap between at least two of the adjacent rib section ends to form a rib encircling the tunnel diameter or other tunnel shape, the rib sections having an I or H shaped cross section with opposing flanges joined by a central web, a plurality of the joined rib sections being provided spaced apart along the length of a tunnel, a plurality of lateral wood or steel beams being provided which connect the joined rib sections, the sides of the lateral beams abutting each other and the ends of the lateral beams being contained within the space between the opposing flanges and butting against the central web of the steel rib sections to form a complete tunnel liner, a clip connector joining the curved steel rib sections together end to end in a friction fit engagement to provide the rib encircling the tunnel to support the lateral beams used to line a tunnel, the clip connector having a generally C shaped cross section with a web section having a width approximately equal to the width of the flange of the steel rib and a length sufficient to overlap the ends of the joined steel rib sections and bridge the gap between the at least two adjacent rib section ends, the clip connector having flanges extending from either side of the web with an inwardly extending edge to wrap around the flange of the steel rib and contain the flange of the steel rib in the space between the inwardly extending edge and the web of the connector the clip connector being slidable longitudinally along the flange of the rib sections until the clip connector engages both ends of the rib sections where the ends of the joined rib sections abut or are separated by a gap without being fixed thereto.