CONSTRUCTION METHOD FOR TUNNEL IN TRANSVERSE SEMI-SOFT AND SEMI-HARD SECTION STRATUM

摘要

A construction method for a tunnel in a transverse semi-soft and semi-hard section stratum, comprising: S1, constructing a pre-buried advanced pipe shed (13) in the area on a tunnel face corresponding to a tunnel arch portion; S2, constructing a soft-rock-distribution left half section (1) and a hard-rock-distribution right half section (2) in sequence by using a center diaphragm method, after excavation is completed, dismantling temporary center diaphragm supports (5, 8), and ensuring that permanent support arch frames (3, 6, 9) respectively constructed on the upper portions of the left half section (1) and the right half section (2) along an arc roof and temporary inverts (7) on the lower portions form a closed support structure; and S3, performing invert excavation, constructing permanent support arch frames (10, 11, 12) at the bottom of the tunnel, dismantling the temporary inverts (7), and constructing a composite lining. The construction method is simple, effectively solves the problem of proneness to collapse during semi-soft and semi-hard section stratum construction, and ensures the normal progress of construction operations and the safety of the construction site.