Arthur Peter Chase
Engineers at Old Post Rd, Rockville, MD

4497590, Feb 5, 1985

Mar 8, 1982

6/356133

Arthur P. Chase - Potomac MD

CRS Group, Inc. - Houston TX

E21D 1100

405152

A prefabricated tunnel lining is disclosed comprised of a plurality of interconnected longitudinally abutting rings, each ring being comprised of a plurality of interconnected ring sections. The ring sections are each prefabricated of concrete with an internally cast steel reinforcement and have overlapping circumferential and longitudinal edges adapted to mate with corresponding edges of circumferentially adjacent sections in the same ring and longitudinally adjacent sections in longitudinally adjacent rings of the liner. Threaded fasteners extend at an angle through holes in the ring segments extending from the inside surfaces of each segment through an edge portion thereof, and communicating with a threaded insert cast into the corresponding mating edge of adjacent sections.