The application of dual-purpose pile in topdown construction can not only save costs,but also make the mechanic condition of substructure walls more rational.

A covered excavation was adopted, which not only eliminated the problem of traffic blockage but also protected the adjacent buildings and services above the foundation pit, with much shorter construction period.

Combined with shallow tunnel of Maoshan west tunnel,this paper compares the covered excavation with open-cut method on technology and economy.

Discussion on the top-down method of the foundation support technology;

A new type of cover-cut method is successfully applied to construction of the rail transit station in the soft ground of Shanghai, which uses the standard and modulus recyclable and reusable temporary pavement system in the soft ground area, with the first support of reinforced concrete also for the support structure of the temporary pavement.

This paper presents the method for construction load determination in cover-cut method.

Based on characteristics of shallow-buried portal section and adjacent existing buildings,cover-cut method is adopted in Houyuntai Mountain Tunnel.