独塔斜拉与连续刚构组合桥梁动力特性及参数影响分析

Research on Dynamic Behavior and Parameter Influence of Single Pylon Cable-Stayed and Continuous Rigid-Frame Composite Bridge

为分析国内首座独塔斜拉连续刚构组合结构体系铁路桥梁的动力特性,以Midas/Civil 2006为平台,介绍其空间有限元模型的建模策略;采用子空间迭代法对这种独特的组合体系进行动力特性分析,给出了前10阶频率和相应的振型;同时,分别计算了恒载集度和弹性模量2种主要结构参数变化对动力特性的影响,并对其规律作出了讨论分析。计算结果表明:斜拉刚构组合结构振动特性兼有斜拉桥和刚构桥的特点,受恒载集度和弹性模量等结构参数变化影响较大。

The dynamic characteristics of the first single pylon cable-stayed and continuous rigid-frame hybrid girder bridge in China are analyzed on the basis of Midas/Civil 2006.The strategies of modeling 3D FEM model in simulating process are introduced.The self-vibration behavior of this unique bridge is analyzed by adopting the subspace iteration method,the first 10 order frequencies and corresponding vibration modes are also given.Meanwhile,different structural parameters,such as dead load intensity and elastic modulus,which have influence on dynamic characteristics,are calculated respectively.Furthermore,its rule is discussed and analyzed.The calculating results indicate that the cable-stayed continuous rigid-frame hybrid bridge possesses both features of the cable-stayed bridge and the continuous rigid-frame bridge;and the hybrid bridge is greatly influenced by dead load intensity and elastic modulus.The analysis results mentioned above provide reference for natural vibration analysis and earthquake-resistance design of this hybrid bridge.