V构—拱组合桥的动力特性分析

Dynamic Characteristics Analysis of a Composite Arch Bridge

在桥梁结构的动力分析中,结构的固有频率和振型、阻尼是其重要的动力特性。而桥梁结构的动力特性与结构本身材料、结构形式、支撑条件等有关。本论文采用有限元软件MIDAS,对某城际轨道V构-拱组合桥建立空间模型,进行动力特性计算分析。本模型主梁、桥墩结构采用变截面的三维空间梁单元进行模拟,吊杆采用桁架单元模拟,钢管混凝土拱肋采用组合截面单元模拟,支座采用弹性连接模拟。计算得出结构的前9阶的频率和模态,研究成果为本桥的动力测试提供了理论计算数据。

In dynamic analysis of a bridge structure,the natural frequency,vibration modes and damp are very important.And the dynamic characteristics are related to the structure material、structure type、sustained conditions and so on.Using the software MIDAS,this paper takes one composite arch bridge as an example to study the dynamic characteristics.The decks and piers are simulated by 3-D beam elements,the suspenders are simulated by link elements,the arch ribs are simulated by composite-section elements,and the bearings are simulated by elastic connectors.The 1st to 9th natural frequency and modes have been listed.The results have provided theory datas for the structure.