结构参数变化对钢管混凝土拱桥动力特性的影响分析

以郑州黄河二桥主跨钢管混凝土拱桥为研究对象,采用ANSYS通用有限元程序,建立了该下承式钢管混凝土拱桥动力计算的整体空间有限元计算模型;探讨了17种不同工况和损伤对桥梁的动力特性的影响。计算结果表明:该钢管混凝土桥竖向刚度相对较强,面外刚度相对较弱;横撑的布置形式对桥跨结构的竖向刚度影响不大,但对桥梁结构对面外刚度影响较大;撑脚的损伤对结构的第1阶自振频率的影响比较敏感的,但对结构的竖向刚度影响不大;吊杆和桥面板的损伤对结构动力特性的影响基本没有变化。

Influence of Structural Parameters Variation on Dynamic Characteristics of Concrete Filled Steel Tubular Arch Bridge

The main bridge of the Zhengzhou Yellow River 2nd Bridge is a concrete filled steel tubular(CFST)arch bridge.Choosing the main bridge as the research object,the finite element procedure ANSYS is used to establish the 3D finite element dynamic model.In order to analyze the influence of structural parameters variation on dynamic characteristics,17 different conditions are considered in the calculation and analysis process.The results show that the vertical rigidity of this CFST bridge is stronger than the lateral rigidity of CFST arch rib.The changes of the transverse brace style have little effect on the vertical rigidity,but have great impact on the lateral rigidity of the CFST arch rib.The brace damage is sensitive to the influence of natural vibration at first step;but the brace damage has little effect on the vertical rigidity.The damages of suspenders and bridge deck slabs influence faintly on dynamic characteristics of the structure.