Research On The Key Technology In Construction Of Open Cut Metro Station-Viaduct Combined Structure

Along with the rapid development of economy and rapid increase of population, traffic condition of the city is worsening,which is becoming one of the bottlenecks to the city’s economic development, so that our government accelerates the construction of traffic facilities, in which rail transit, viaduct are commonly choice. At some old districts of city, as road width is limited, subway station has to share traffic channel with the viaduct. As with the fact,the metro station constructing combined with viaduct as a whole project is putting forword, which is considered to be a good solution for reducing demolition of nearby buildings and pipelines, shortening the construction period and saving investment. However, the station-viaduct combined project is scarce currently and mature construction experience is limited. Some problems are presented during design and construction process.Wuhu station and Nanyihuan station of the first rail transit of Hefei are on the construction with viaduct. Based on this two subway station-viaduct combined project, This paper studied the subway station-viaduct combined structure by Literature researching, theoretical analysis, numerical simulation method.The main achievement of the paper were summarize as follow:(1) This paper proposed the subway station-viaduct parity combination structure:this kind of combination structure occupies minimum area, reduces the impact to existing pipelines; the subway station being used as the foundation of viaduct, there is no to construct pile foundation and pile cap for the viaduct; this kind of structure guarantee the normal function of subway station, t the standard form of he viaduct pier and has no impact on the landscape.(2) By studying the mechanical characteristics of different combination structure, this paper proposed subway station-viaduct " separate combination " structure, this Kind of structure consisting of bridge pile foundation and platform, steel pipe column of subway station, foundation and pier column of bridge, in which the bridge pile foundation and platform was consolidated by steel pipe column of subway station and foundation and pier column of bridge" float "on the subway station.(3) At curve segment of the city road, the erection of viaduct is difficult, the article puts forward to using " Pi" type door frame system, in order to achieve rapid, accurate installation of steel box girder and studied the mechanical characteristics of station-viaduct combination structure when it locates at curve segment of the road. The result showed that as temporary supports overlap on the net of column of subway station, the station structure can meet safety requirements.