环境激励下高桩码头物理模型模态实验  

Modal Experiment of Physical Model for High-Piled Wharf Under Ambient Excitation

作　　者：孙熙平[1,2] 王元战[1] 赵炳皓[1] 

机构地区：[1]天津大学天津市港口与海洋工程重点试验室,天津300072 [2]交通运输部天津水运工程科学研究所水工构造物检测、诊断与加固技术交通行业重点实验室,天津300456

出　　处：《振动．测试与诊断》2013年第2期263-268,340,共6页Journal of Vibration,Measurement & Diagnosis

基　　金：西部交通建设科技资助项目(200932800008);交通运输部行业重点实验室应用基础研究资助项目(2011329224180)

摘　　要：建立高桩码头物理模型,进行环境激励下的模态实验研究。利用特征系统实现算法(eigensystem realization algorithm,简称ERA),结合自然激励技术(natural excitation technique,简称NExT),即NExT-ERA模态识别方法编写模态识别程序来识别物理模型的模态参数,并与有限元模型的计算结果进行对比分析。研究结果表明,物理模型实验值与有限元计算结果相比,二者数值接近,误差很小,说明NExT-ERA模态识别方法能够应用于环境激励下高桩码头的模态识别。环境载荷激励下结构的动力响应信号较弱,结构的高阶模态一般无法激出,某些数据识别出的模态参数存在"漏阶"现象,因此结合有限元模型进行分析非常必要。A physical model for high-piled wharf is established to perform experimental study on the model under ambient excitation.The modal identification procedures are written by the modal identification method NExT-ERA to identify modal parameters of the physical model.The results show that the values from these two methods are very close and the error is very small,which shows the application of the modal identification method NExT-ERA to the modal identification of high-piled wharf under ambient excitation.From the experimental results,it is found that the structural dynamic response signals under ambient excitation is weak,higher order modes of structure are usually difficult to excite,and the modal parameters identified by some data are usually missing,thus it is necessary to perform the analysis combined with finite element model.

关 键 词：环境激励 高桩码头 模态实验 NExT—ERA模态识别 有限元计算 

分 类 号：TV323[水利工程—水工结构工程] TH113[机械工程—机械设计及理论]