中文摘要：

为了解多跨连续斜桥振动频率的变化规律和冲击系数的合理取值,建立了等截面多跨斜桥振动频率求解的递推算法和斜桥振动分析的有限元列式,比较了等跨径多跨连续斜桥和不等跨径多跨连续斜桥前5阶频率的变化,分析了两跨连续斜桥的车-桥振动,给出了跨中截面挠度、弯矩的时程曲线,考察了斜度对挠度和弯矩的影响、挠度和弯矩的冲击系数随车速、斜度的变化。算例结果表明,等跨径多跨连续斜梁基频与单跨斜梁一致,单跨斜梁的高阶频率分布在多跨斜梁的高阶频率中,其间夹杂有其它振型频率,随着跨数的增加,夹杂的振型频率也越多;斜度对斜桥动力特性有重要影响;车辆的冲击效应与车速、斜没之间没有单调变化规律;挠度和弯矩的冲击系数不同。

英文摘要：

To explore the vibrating frequencies and rational impact factors of multi-span skew bridge,the recursive algorithm of vibrating frequency and finite element formulations of static and dynamic analysis are established for uniform section multi-span continuous skew bridge.The first five order frequency changes of equal-span multi-span continuous skew bridge and unequal-span multi-span skew bridge are compared.The interaction of vehicle-bridge system for two-span skew bridge is analyzed.The history curves for deflection and moment of middle-span are presented.The influence of obliquity on dynamic deflection and dynamic moment as well as the influence of vehicle velocity and obliquity on impact factors of deflection and moment are investigated.Results show that the fundamental frequency of multi-span skew bridge is identical to that of single span skew bridge.The higher order frequencies of single span skew bridge are distributed in frequencies of multi-span skew bridge,which mix other vibrating frequencies.The more the span number is,the more the other vibrating frequencies mingle.Obliquity has an important influence on dynamical characteristics of skew bridge.Impact effects of vehicle have no harmonious changing rule with vehicle velocity and obliquity.The impact factors of deflection and moment are different for skew bridge.