基于车桥接触点响应和盲源分离的桥梁模态识别  

Modal Identification for Bridge Based on Contact Point Response and Blind Source Separation of Moving Vehicles and Bridge

作　　者：李岩[1] 施雪晴 刘文 LI Yan;SHI Xueqing;LIU Wen(School of Transportation Science and Engineering,Harbin Institute of Technology,Harbin 150090,China;Shanghai Municipal Engineering Research Institute(Group)Co.,Ltd,Guiyang Branch,Guiyang 550002,China)

机构地区：[1]哈尔滨工业大学交通科学与工程学院,黑龙江哈尔滨150090 [2]上海市政工程研究总院(集团)有限公司贵阳分公司,贵州贵阳550002

出　　处：《湖南大学学报（自然科学版）》2023年第5期55-64,共10页Journal of Hunan University:Natural Sciences

基　　金：国家重点研发计划项目(2021YFB2600500);黑龙江省自然科学基金资助项目(LH2019E049)。

摘　　要：针对基于车辆响应的间接测量法进行桥梁模态识别时,桥面不平度的影响难以滤除、高阶模态识别准确率较低等问题,提出一种基于盲源分离算法来分离车桥接触点响应信号中的桥面不平度效应与桥梁振动响应,进而实现桥梁模态识别的方法.首先,详细阐述了应用二阶盲识别(Second Order Blind Identification,SOBI)算法,以两组车桥接触点加速度响应信号作为输入信号,进而获取桥梁振动估计信号的原理和方法.然后,采用信号带通滤波和Hilbert变换并结合支点数据延拓的振型修正策略,建立了基于车辆响应的桥梁模态识别技术流程和框架.最后,依托数值算例对所提出方法的适用性和有效性进行了验证,并分析了车辆间距、桥面不平度和车辆频率等参数对方法适用性的影响.结果表明,所提出方法能有效滤除桥面不平度的影响,实现桥梁高阶模态的准确识别,且对多种关键因素的影响具有鲁棒性,具有精度高、操作简便和适用性强等特点,可为基于车辆响应的桥梁模态识别提供一种新思路.Aiming at the problems that the influence of bridge deck roughness on bridge vibration is hard to re⁃move and the low accuracy of high-order modal recognition during the current indirect measurement method based on vehicle response,this paper proposes an approach to separate the effect of bridge deck roughness and bridge vi⁃bration response by using blind source separation identification based on the acceleration response signal of the axle contact point,to identify the bridge modality.Firstly,the principle and method of obtaining the bridge vibration esti⁃mation signals by using the second order blind identification(SOBI)algorithm and taking the acceleration response signals of two groups of vehicle-bridge contact points as input signals are described in detail.Then,the bridge modal identification technology flow and framework based on vehicle response are established using signal band-pass filtering and Hilbert transform combined with the mode modification strategy of fulcrum data extension.Finally,the appli⁃cability and effectiveness of the proposed method were verified by numerical examples,and the influences of vehicle spacing,bridge deck roughness,and vehicle frequency on the applicability of the method were analyzed.The results show that the proposed method can effectively filter the influence of bridge deck roughness,achieve accurate identifi⁃cation of high-order modes of bridges,and show robustness under the influence of multiple key factors.Moreover,the proposed method has the characteristics of high precision,simple operation,and good applicability,which can provide a new idea for bridge modal identification based on vehicle response.

关 键 词：移动车辆 桥面不平度 车桥耦合振动 间接测量 桥梁 模态识别 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]