Study on Structural Design and Driving Process of Subway Station Passageway Crossing Urban Trunk Road by Tunneling Method

Abstract

On the basis of unfavorable geology of a passageway in subway station to cross urban trunk road with heavy traffic flow in Chengdu city, the comparison of two different driving methods for the underground passageway with three arches and two pillars is carried out in the paper. The result shows that both center drift-pillar method and partial bench-cut method can be used to build the passageway in the subway station. But the latter is superior to the former in reducing construction cost, risk and timescale. While the former is more efficient in controlling ground subsidence. The tubular roof protection is also designed to reinforce the shear strength of soil above the crown of the passageway before excavating the poor surrounding soil. The inventive driving procedure of partial bench-cut method presented in the paper can be utilized to guide the rational design and economical construction of shallow passageway for subway station to cross urban trunk road in weak geological strata.