厦深铁路榕江特大桥连续钢桁梁柔性拱组合桥成桥静、动载试验及结构性能研究

厦深铁路榕江特大桥（110＋2×220＋110）m连续钢桁梁柔性拱桥系同类结构中最大跨度结构,介绍理论分析和成桥桥静、动载试验方法,进而以构件应力、结构变位和刚度、结构的自振频率、振型、阻尼比、动力系数、振幅动态参数为主要对象,对结构的性能进行评价,研究结果表明：该结构符合规范和使用要求。结合试验结果中横向基频高于理论值和大吨位支座在活载作用下水平变位基本为0的现象,对正交异性整体钢桥面的有限元模型模拟精度、活动支座模型模拟等进行了深层次探讨,提出理论模型建立中避免弱化桥面板刚度和应重视支座实际变位情况的具体建议,对同类结构具有参考价值。

Static and dynamic loading tests and structural analysis for Rongjiang river bridge with continuous steel truss and flexible arch in Xiamen-Shenzhen railway

The structure of Rongjiang river bridge in Xiamen-Shenzhen Railway,which is composed of continuous steel truss and flexible arch and has main spans of 110 plus 2 multiple 220 plus 110 meters,is the longest among the type. In this paper,theoretical analysis and static and dynamic loading tests were carried out for evaluating on the structural performance by taking into account stress,strain,rigidity,natural frequency,vibration mode,damping ratio,dynamic coefficient and dynamic parameters of amplitude. The evaluation result shows that the structure satisfies the standards and requirements. According to the testing results that fundamental frequency of transverse vibration mode is greater than theoretical value and horizontal deflection on bearing approaches 0under large tonnage of live load,further studies on precision in finite element model of the integral deck in orthotropic steel bridge and simulating expansion bearings were conducted. Finally,specific suggestions about avoiding weakening rigidity of the deck when establishing theoretical models and emphasizing the practical shifts of bearings were proposed,which provides valuable reference value for the similar structures.