STRUCTURE OF DIVERGING/MERGING SECTION OF BRANCH TUNNEL, AND ITS CONSTRUCTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a structure of a diverging/merging section of a branch tunnel 2, which can be inexpensively, toughly and safely constructed in a short period of time by narrowing a range for regulating the traffic of an in-service road, corresponding to a cut-and-cover section, on the ground, and a construction method of the structure.;SOLUTION: A continuous underground wall body 3 is constructed along a main-line tunnel 1, and the branch tunnel 2 is constructed between the tunnel 1 and the wall body 3 in such a manner as to diverge from/merge into the tunnel 1. In the structure of the diverging/merging section of the branch tunnel 2, earth retaining materials 8 and 9 are elongated toward the wall body 3 from upper and lower sections of the tunnel 1. A lining body of reinforced concrete or steel-frame concrete is constructed in an internal space which is enclosed with the materials 8 and 9, the tunnel 1 and the wall body 3. A diverging/merging section space 18 is formed inside the lining body, so that a diverging/merging section skeleton 17 can be constructed.;COPYRIGHT: (C)2006,JPO&NCIPI