TUNNEL EXCAVATING CONSTRUCTION METHOD AND TUNNEL LINER USED THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a tunnel excavating construction method and a tunnel liner used in this construction method of excavating with a tunnel boring machine using the tunnel liner lightweight and low in cost compared with segments and making the degree of support reinforcement changeable according to the state of the natural ground in a tunnel in a mountain. SOLUTION: Each constituent member of a prefabricated tunnel liner 10 composed of a plurality of main girder rings 1 using shape steel, and a deck plate 2 provided bridging between a plurality of main girder rings, is manufactured outside of a tunnel T. Each constituent member in a bulk state or in a unit built-up state is carried into an excavation site in the tunnel T reinforced or omitted according to the state of the natural ground to build up the prefabricated tunnel liner 10, and a tunnel boring machine M is put in excavating action.