IMPROVED TUNNEL LINER BUILDING METHOD AND BUILDING PANELS THEREFOR

摘要

Tunnel liners are formed from panels (10) of arched sheet material. The panels include a central portion (12), inclined side portions (14, 16) and wing portions (18, 20). One of the wing portions has a hook portion (22) and the other of the wing portions has a receptacle portion (28). The hook portions and receptacle portions are constructed so as to snap-fit with respective receptacle portions and hook portions of adjacent panels. Panels can thus be more easily assembled together. Panels can also be continously seamed together from the underside, i.e., from within an arched assembly of panels.