Optimization of Suspender Tension Scheme of Cast-in-Situ Tied Arch Bridge with Support

Abstract

The suspender tension sequence and construction cable force of tied arch bridges have a greater impact on the internal force and deformation of the structure. In order to obtain a reasonable suspender tension plan, make sure that the internal force of the structure meets the specific requirements and is evenly distributed during the construction process to avoid the excessive internal force mutation, seven suspender tension schemes were proposed. Combined with the example of a half-through concrete-filled steel tube tied arch bridge project, this scheme introduces the “kurtosis coefficient” evaluation index, and compares and analyzes the changes in the internal force of the structure under different suspender tension schemes. In this paper, the pros and cons of each scheme/part were also discussed. The results show that the difference between the internal force of the bridge and the cable force during the bridge completion stage of each scheme is relatively small, which has a greater impact on the internal force of the bridge during the construction phase. Among them, the symmetrical sequential tension scheme is convenient for construction, but the local position (such as arch foot, arch top, 1/4 arch rib) the internal force changes obviously, and there will be a large peak value, which will affect the safety of the structure during the construction process; the symmetrical interval tension plan can improve the structural force condition and reduce the internal force peak value, but the overall trend is basically unchanged; the internal force distribution of the symmetrical alternating tensioning scheme is uniform, without major sudden changes, and no obvious peaks, so that the safety of the bridge construction process is more guaranteed.