环境激励下移动车辆对桥梁模态参数识别的影响研究  

Effects of moving vehicle on bridge modal parametric identification under ambient excitation

作　　者：贺文宇 丁绪聪 任伟新[1,2] HE Wenyu;DING Xucong;REN Weixin(Department of Civil Engineering,Hefei University of Technology,Hefei 230009,China;Anhui Engineering Laboratory for Infrastructural Safety Inspection and Monitoring,Hefei 230009,China)

机构地区：[1]合肥工业大学土木与水利工程学院,合肥230009 [2]安徽省基础设施安全检测与监测工程实验室,合肥230009

出　　处：《振动与冲击》2021年第3期48-53,共6页Journal of Vibration and Shock

基　　金：国家自然科学基金(51878234);中央高校基金(JZ2019HGPA0101)。

摘　　要：基于环境激励的模态参数识别方法在桥梁健康监测领域应用广泛,所识别桥梁的模态参数的变化常用来进行损伤识别。然而在模态参数识别过程中,移动车辆本身具有的质量属性被忽视,仅被当作为环境激励的一部分。桥梁损伤导致的模态参数变化将被移动车辆所引起的变化掩盖,影响后续损伤识别的效果。以随机子空间法为例,研究环境激励下的模态参数识别方法识别的桥梁模态参数的变异情况,并对比桥梁局部损伤导致的桥梁模态参数的变化量,结果表明局部损伤和移动车辆都会造成频率减小和振型改变,因此在实际模态测试中需要考虑移动车辆作用并剔除其影响。Modal parametric identification under ambient excitation is widely used in the field of bridge health monitoring,and identified modal parameters are often employed for bridge damage detection.However,in process of modal parametric identification,the mass attribute of mobile vehicle itself is ignored and only regarded as a part of environmental excitation.The changes of modal parameters caused by bridge damage are covered by changes caused by moving vehicles to affect the effect of subsequent damage identification.Here,the variation of bridge modal parameters identified with the modal parametric identification method under ambient excitation was studied,and compared with the variation of bridge modal parameters caused by local damage of bridge.The results showed that both local damage and moving vehicle can reduce bridge modal frequencies and change its modal shapes,so it is necessary to consider action of moving vehicle,and eliminate its effects in actual modal testing.

关 键 词：模态参数识别 移动车辆 桥梁损伤 随机子空间法 环境激励 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3