环境激励及噪声干扰下斜拉桥的损伤定位方法  

DAMAGE LOCALIZATION METHOD OF LONG-SPAN CABLE-STAYED BRIDGES UNDER AMBIENT EXCITATION AND NOISE DISTURBANCE

作　　者：侯立群[1] 欧进萍[1] 

机构地区：[1]哈尔滨工业大学土木工程学院,哈尔滨150090

出　　处：《振动与冲击》2008年第8期1-6,共6页Journal of Vibration and Shock

基　　金：国家自然科学基金重大国际合作项目(中、美、日)-重大工程结构的智能健康监测(50410133);2004~2006国家自然科学基金项目:“重大工程结构健康监测及其集成系统”,项目编号:50538020.2006~2009

摘　　要：损伤识别是结构健康监测的核心技术之一,但至今仍没有很好的解决方法。测试噪声及各种环境不确定性干扰所导致的模态参数识别精度不高是制约损伤识别技术走向实用化的关键问题之一。针对这种情况,考虑到噪声干扰的随机性及损伤特征的稳定性,提出了基于三点直线拟合曲率的损伤综合定位方法。此方法表述如下:利用结构损伤前后多次识别得出的模态振型求得一组曲率差,将这一组曲率差中稳定为正的位置认定为损伤位置,将时正时负的位置认定为无损位置。在滨州黄河公路大桥有限元模型上进行了损伤定位的仿真分析,仿真中对滨州黄河公路大桥有限元模型共设置6种损伤情况,分别研究了在2%和5%噪声水平下的损伤定位效果,结果表明,此方法抗噪声能力较强,除上述第2种损伤情况外,其余损伤位置均能可信地判定。To solve the problem of low precision of modal identification in conventional. damage detection techniques, considering the randomness of noise and the stability of damage feature, a kind of integrative damage localization method based on three-points matching curvature was introduced. The method can be described as follows: obtain a group of curvature differences from modes identified from no-damaged and damaged structures, take the location at which curvature difference in the group is always positive as the damage location and take the location at which curvature difference is sometimes negative as the no-damage location. The computer simulation of Bin Zhou Yellow River Highway Bridge was implemented. Six damage locations were set in the simulation process and two situations of 2% and 5% noise were studied. The simulation result shows that the method has good ability of noise resistance and can generally identify the location of damage correctly except damage No.2.

关 键 词：健康监测 损伤识别 噪声 曲率 环境激励 斜拉桥 

分 类 号：U446[建筑科学—桥梁与隧道工程]