基于间接法识别的桥梁振型的损伤定位方法  

A damage localization method based on indirectly identified mode shapes

作　　者：贺文宇 何健 任伟新[1] HE Wenyu;HE Jian;REN Weixin(Department of Civil Engineering,Hefei University of Technology,Hefei230009,China)

机构地区：[1]合肥工业大学土木与水利工程学院,合肥230009

出　　处：《振动与冲击》2018年第24期13-17,共5页Journal of Vibration and Shock

基　　金：国家自然科学基金(5151878234; 51508145)

摘　　要：基于模态振型曲率变化的损伤定位法具有原理简单、结果直观、效率较高的优点,但其对高空间分辨率和基准振型的需求及中心差分法导致的低抗噪性,极大的限制了其应用范围。提出了一种基于间接法识别的桥梁振型的损伤定位指标。利用希尔伯特变换从移动车辆响应中提取出高空间分辨率的损伤桥梁振型;采用区域振型曲率替代传统的振型曲率,多项式拟合估计未损桥梁的振型信息,综合有损与无损的区域振型曲率定义损伤定位指标;通过数值算例验证了所提出指标的有效性,并探讨了测试噪声、路面粗糙度等对定位精度的影响。Mode shape curvature change based damage localization methods possess the advantages of simple principle,intuitive results,and high efficiency.However,their application is limited by the requirement for high spatial resolution and reference mode shapes,and the central difference induced low anti-noise ability.This paper develops a new damage localization index(DLI)by using indirectly identified mode shapes.Firstly,the high spatial resolution mode shape in a damaged state was extracted from the moving vehicle response via the Hilbert transform.Then regional mode shape curvature(RMSC)was defined,and the mode shape information in an undamaged state was estimated by polynomial approximation.Finally,a DLI was formulated based on RMSC before and after damage to localized damage.Numerical studies were conducted to examine the effect of noise,and road roughness on the accuracy of the proposed DLI.

关 键 词：损伤定位 间接法 振型 高空间分辨率 

分 类 号：TN911.6[电子电信—通信与信息系统] TU311.3[电子电信—信息与通信工程]