铁道标准设计2018，Vol.62Issue(6)：77-82,6.DOI:10.13238/j.issn.1004-2954.201707110005
大跨公轨两用悬索桥动力特性的参数敏感性分析
Parameter Sensitivity Analysis of Dynamic Characteristics of Long-Span Road-Rail Suspension Bridge
摘要
Abstract
To investigate the dynamic characteristics of long-span road-rail suspension bridges,a full-bridge discrete unit finite element model is established by Midas/Civil based on the 3rd Maling River Bridge in Guizhou.Modal analysis is conducted with subspace iteration method to obtain the natural frequencies and the mode shape of the bridge.Then the control variable method is employed to analyze the effects of seven key structural parameters,including pylon stiffness,cable stiffness,girder stiffness,boom stiffness,dead load,central buckle and wind-resistance bearing.The results indicate that the fundamental frequency of the bridge is 0.172 316 Hz and the corresponding vibration mode is the first symmetric lateral bending mode of the main girder.The fundamental frequency of the road-rail suspension bridge is higher than that of the normal highway suspension bridge,and the integral stiffness is also high.The increase of the pylon stiffness can increase the lateral vibration frequency of pylon.With the increase of the cable stiffness,the first vertical vibration and torsion frequencies of the main girder increase significantly.The increase of boom stiffness improved the lengthways flutter frequency to some degrees.With the increase of girder stiffness,the lateral bending and torsion frequencies of the main girder are increased significantly and the performances of structural lateral stiffness and flutter are improved.However,the increase of dead load intensity can decrease the lateral vibration,the vertical vibration and the torsion frequencies of the main girder by different degrees,while,the central buckle and the wind-resistance bearing can improve the integral structure stiffness effectively.关键词
悬索桥/公轨两用桥/结构参数/子空间迭代法/动力特性/振型/频率Key words
Suspension bridge/Combined bridge/Structure parameter/Subspace iteration method/Dynamic characteristics/Vibration mode/Frequency分类
交通工程引用本文复制引用
张兴,杜斌,向天宇..大跨公轨两用悬索桥动力特性的参数敏感性分析[J].铁道标准设计,2018,62(6):77-82,6.基金项目
贵州大学研究生创新基金项目(2017033) （2017033）
贵州省科技支撑计划项目(黔科合支撑2016[2047]) （黔科合支撑2016[2047]）
