基于环境激励的某大桥有限元模型修正  

Modification of Finite Element Model of a Bridge based on Environmental Excitation

作　　者：郑兴华 刘浪[2] 陈艳[2] ZHENG Xinghua;LIU Lang;CHEN Yan

机构地区：[1]宁波市城建设计研究院有限公司,浙江宁波315000 [2]重庆交通大学,重庆400074

出　　处：《浙江建筑》2025年第2期6-10,共5页Zhejiang Construction

摘　　要：以一座三跨预应力混凝土连续箱梁桥工程为例,开展基于环境激励的桥梁振动试验,利用连续采集的加速度时程数据,采用SSICOV识别结构模态参数,与建立的桥梁初始理论有限元模型参数进行对比;通过灵敏度分析法选取修正参数,分别基于1阶优化算法和响应面法对桥梁有限元模型进行修正。结果表明:修正模型的计算频率与实测频率的误差显著减小,最大相对误差从修正前的8.30%降低到1.67%,最小相对误差从5.34%降低到0.05%,表明其动力特性与实测动力特性吻合良好,能够准确反映该桥的实际工作状况。In this study,a PSC continuous box girder bridge with three spans was selected to perform on‑site environmental vibration test,by which,a large number of acceleration time history data was collected to identify the structure modal parameters by SSI‑COV method and compared with the paraweters of the established initial theoretical finite element model of the bridge.A sensitivity analysis was performed to select correction parameters,then the first‑order optimization algorithm and response surface method were used to modify the theoretical FEM for the bridge,respectively.The results show that the frequencies of the modified FEM were very closed to the measured ones,the largest difference between them reduced from 8.30%to 1.67%,and the smallest difference reduced from 5.34%to 0.05%,which means the modified FEM has more accurate dynamic characteristics reflecting the real operating condition.

关 键 词：模态参数识别 灵敏度分析 有限元模型修正 

分 类 号：TU311.3[建筑科学—结构工程]