Abstract:With the gradual increase of overpass bridges in China, the traditional overpass construction will inevitably have a certain impact on the existing lines. The steel shell closure technology can effectively avoid the impact on the existing lines, ensure the safe operation of the existing lines, and is very suitable for the closure section construction of prestressed concrete structures. Relying on the super-large bridge in Zhangzhou Downlink of the newly built Fuzhou-Xiamen Railway, the composition, processing and installation of steel shell closure technology is briefly described. The finite element model of the steel shell of the mid-span closure section is established by using the large-scale finite element software Ansys to analyze the stress and strain of the steel shell of the closure section during the concrete pouring process, which provides a basis for guiding the concrete construction of closure section and the smooth closure of bridge.