钢管混凝土拱桥横撑形式对稳定性的影响研究

Study on Influence of Bracing Forms on Stability of Concrete-filled Steel Tube Arch Bridges

摘要:

以一座200 m跨径的下承式钢管混凝土拱桥为研究对象，采用数值模拟方法，分析了不同横撑形式对结构基频、最大横向变形和整体稳定系数的影响。研究结果表明，设置横撑能显著提高结构的横向刚度，降低横向变形，提升整体稳定性。其中，设置横撑后，结构基频最大可增加207%，最大横向变形可减少90.4%，整体稳定系数可增加399%。此外，通过引入结构稳定性经济指标η评估横撑的经济性，发现米字型横撑虽然提供较高的横向刚度和稳定性，但其经济性低于K型和L型横撑。因此，在满足结构稳定性要求的前提下，建议优先选择经济性更优的K型或L型横撑，可为同类型桥梁的设计提供参考。

Abstract:

Taking a 200-m span through concrete-filled steel tube arch bridge as a research object, the numerical simulation method is used to analyze the effects of different bracing forms on the fundamental frequency, maximum lateral deformation and overall stability coefficient of the structures. The results indicate that the setting up of of bracing can significantly enhance the lateral stiffness of the structure, reduce the lateral deformation, and improve the overall stability. Specifically, the fundamental frequency of the structure can increase by 207%, the maximum lateral deformation can decrease by 90.4%, and the overall stability coefficient can increase by 399% after the bracing is set up. Furthermore, by introducing the structural stability economic index η to evaluate the economy of the bracing, it is found that the cross-shaped bracing provides the higher lateral stiffness and stability, but its economic efficiency is lower than K-shaped bracing and L-shaped bracing. Therefore, under the premise of meeting the structural stability requirements, it is recommended to give priority to the K-shaped bracing or L-shaped bracing with more economy, which can provide the reference for the design of similar bridges.