Operational analysis of long-span steel box self-anchored track suspension bridge

The long-span steel box self-anchored track suspension bridge is prone to deformation under long-term train and temperature loads, which seriously affects the structural safety and operation performance. To ensure the operational performance of the long-span steel box self-anchored track suspension bridge, this paper determines the operational performance evaluation index through an investigation and analysis of relevant norms and standards from both domestic and international sources. Based on the theory of couple vibration and track irregularity, Midas/Civil software was used to analyze the vertical displacement of a long-span steel box self-anchored track suspension bridge under loads such as train and temperature, and put forward the operation safety classification evaluation index and derived the control value, and verified the index combined with the actual project. The results show that the down-torsion will significantly change the structure alignment and seriously affect the operation performance of the bridge. Due to the limited adjustment of the number of fasteners of long-span ballastless track Bridges, the deformation range should be set effectively. Based on the analysis results, the maximum vertical deformation safety control value of the railway suspension bridge during operation is L/500, and the early-warning control value is L/600. Compared with the current monitoring standards, the safety control value is slightly smaller, and the warning value is the same. Through the real bridge test, the rationality of the maximum vertical deformation control value in the operation stage is verified.