Stress optimization analysis of long-span concrete-filled steel tube arch bridge based on Midas full-bridge finite element analysis model

CFST is a new building material developed on the basis of steel bars and concrete, which is frequently employed in bridge construction in China. The arch rib is the main stress part CFST arch bridge has a long span, and the safety of the arch rib directly determines the working performance of the whole bridge. Therefore, to better understand the stress of the arch bridge and ensure its safety of the bridge, the research employs the finite element program Midas to establish a long span concrete filled steel tube full bridge model and analyzes axial force, stress, and displacement of arch rib in each construction stage of the arch bridge. The results show that in different construction stages, the axial force on each section increases gradually. The upper and lower edges of the steel pipe are shown as a gradually increasing negative stress. The displacement change between each section is between (2-4) mm. To sum up, the finite element full bridge analysis based on Midas can accurately obtain the stress state of long-span bridges with CFST arcs. By using this technology, data from large-span CFST arch bridges may be efficiently employed in bridge optimum building, improving the load-bearing capabilities of the arch bridge.