基于车激响应和灵敏度分析的桥梁结构损伤识别方法研究  

DAMAGE DETECTION OF BRIDGES BASED ON TRAIN-INDUCED BRIDGE RESPONSE AND SENSITIVITY ANALYSIS

作　　者：战家旺[1] 夏禾[1] 陈上有[2] De Roeck G 

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]中交公路规划设计院有限公司桥梁技术中心,北京100088 [3]鲁汶大学土木工程系

出　　处：《工程力学》2011年第11期38-44,共7页Engineering Mechanics

基　　金：国家自然科学基金项目(51078029);中央高校基本科研业务费专项资金项目(2009JBM061);比利时-中国政府间合作项目(BIL07/07);中国交通建设股份有限公司科技研发项目:铁路;轻轨;公铁(轨)桥梁车-桥耦合振动仿真分析研究

摘　　要：提出了一种利用桥梁结构在车辆荷载作用下在线响应评估结构性损伤的方法。以单元弯曲刚度的变化量为识别指标,基于车桥动力相互作用理论计算车激桥梁响应以及响应对损伤指数的灵敏度,以结构不同状态下的响应残差为约束条件,利用最小二乘法求解灵敏度方程得到各单元的损伤指数,然后通过有限元更新技术和反复迭代,最终实现对桥梁损伤的定位和定量分析。分析了测量噪声和轨道不平顺对损伤识别结果的影响规律。数值算例表明,所提的损伤识别方法对轨道不平顺和量测噪声不敏感,可以利用加速度、速度或者位移响应有效识别桥梁的绝对损伤或相对损伤。A damage evaluation method for bridges, using their online dynamic responses under passingvehicles, is proposed. The perturbation of the elemental identification. The train-induced bridge responses and flexural stiffness is used as an index for bridge damage the response sensitivities to the damage indexes are calculated based on the train-bridge dynamic interaction theory. Using the response differences between different states as restriction conditions, the sensitivity equation is solved by the least-squares method to get the damage indices, and then the damages are located and quantified by the finite element model updating technique and numerical iteration. A numerical example shows that the proposed damage identification method is insensitive to the railway irregularities and the measurement noises, and that the absolute damage or relative damage of the structure can be effectively identified by acceleration, velocity or deflection responses in railway bridges.

关 键 词：桥梁 损伤识别 有限元模型更新 车激响应 灵敏度分析 损伤指数 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]