苏通长江公路大桥最大单悬臂施工状态结构模态参数识别  

Modal parameters identification of Sutong Yangtze River highway bridge at stage of single longest cantilevered beam state

作　　者：陶奇[1] 廖海黎[1] 李明水[1] 刘明[1] 

机构地区：[1]西南交通大学风工程试验研究中心,四川成都610031

出　　处：《四川建筑科学研究》2009年第5期40-44,共5页Sichuan Building Science

摘　　要：将HHT法与随机减量技术相结合,利用现场实测的位移时程信号,对苏通长江公路大桥主梁最大单悬臂施工状态结构模态参数进行了识别。所识别出的频率与有限元分析的结果相近,识别出的模态阻尼比与《公路桥梁抗风设计规范》给定值差别较大。表明运用本文所提出的方法进行结构模态参数识别是有效的,规范所给阻尼比值具有很大离散性。针对不同特大桥梁有必要进行相应模态阻尼比实测,以便满足施工和设计的需要。The modal parameters of Sutong Yangtze river highway bridge girder at stage of single longest cantilevers are identified with the actual measured displacement time history datum by HHT method and random decrement technique. The identified dominant frequencies are closed to that calculated by FEM. And the modal dumping ratio exist obvious difference to what the criterion request. So, it shows that the modal parameters identification method is effective,while the criterion gives a discrete damping ratio. Then,the actual measurement is needed to confirm the modal damping ratio of every particular long span bridge to satisfy the request of construction and designation.

关 键 词：HHT 随机减量技术 模态参数 

分 类 号：TU311.3[建筑科学—结构工程] O329[理学—一般力学与力学基础]