| 摘要 |
PROBLEM TO BE SOLVED: To provide a structure and a method sufficiently endurable as the whole small diameter tunnel group, by surely reinforcing a joining part, even if an unbalanced load acts when excavating a large space enclosed by a small diameter shield tunnel in a process thereafter, by adopting a method for not only reinforcing concrete of a preceding tunnel T1 but also reinforcing concrete of a succeeding tunnel T2, in the method for constructing a large diameter tunnel by connecting a plurality of mutual small diameter shield tunnels bored in parallel by a shield machine M.SOLUTION: The method is provided for constructing the large diameter tunnel by connecting the plurality of mutual small diameter shield tunnels bored in parallel by the shield machine M, and uses a steel segment 1 constituted by installing a dislocation preventive steel material 14 on an outside surface, and is constituted so that the outside dislocation preventive steel material 14 of a skin plate 11 of the steel segment 1 is positioned inside a cylindrical filling body B formed on the outer periphery of the small diameter tunnel. |
