Structural stress analyses of long-span railway extradosed cable- stayed bridge based on reasonable construction state

Abstract

The system of the extradosed cable-stayed bridge constantly changed during construction. In order to obtain the reasonable finished dead state and ensure the structural safety during construction, it is necessary to deeply investigate the construction stages. A finite element model of a real long- span railway extradosed cable-stayed bridge built in China was established by using MIDAS/Civil finite element software to analyze the stress and deformation of the bridge based on reasonable construction state. The results show that it should be paid attention to the longitudinal displacement at the top of the tower after the middle-span closure stage, and the vertical displacement of the girder in the longest single cantilever stage. The maximum compressive stresses of the tower appeared after the cable tensioning and the girder appeared when the bridge is in the longest single cantilever state are less than the design compressive strength of concrete C55. The maximum tensile stress of the girder appeared when the bridge is in the longest double cantilever state is less than the design tensile strength of concrete C55.