TUNNEL CONSTRUCTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a tunnel construction method for constructing an approach section ranging from a ground without the need for constructing a shaft. SOLUTION: The tunnel construction method comprises a start section construction step of constructing a start section where a shield machine 1 starts, an approach section initial construction step of using a heavy machine 3 for drilling the ground on the upper side of the ceiling of the shield machine 1 which digs obliquely downward from the start section and of installing a segment 4 with its sectionally rectangular upper part opened in a range up to a preset depth and installing a sectionally rectangular segment 4 in a range deeper than the preset depth, and an approach section following construction step of constructing the lower stage of the approach section 6 extending from the approach section 6 constructed in the approach section initial construction step, constructing the upper stage thereof in a range up to the preset depth while using the shield machine 1 with its ceiling being opened for advancing along the segment 4 provided on the lower stage, and constructing the upper stage thereof in a range deeper than the preset depth while using the shield machine 1 with its opening portion closed for advancing. COPYRIGHT: (C)2005,JPO&NCIPI