运用改进残余力向量法的结构损伤识别研究  

Structural Damage Identification by Using Improved Residual Force Vector

作　　者：何伟[1,2] 陈淮[3] 王博[1] 李静斌[3] 

机构地区：[1]郑州大学水利与环境学院,郑州450001 [2]华北水利水电学院土木与交通学院,郑州450011 [3]郑州大学土木工程学院,郑州450001

出　　处：《振动．测试与诊断》2009年第4期379-382,共4页Journal of Vibration,Measurement & Diagnosis

基　　金：高等学校博士学科点专项科研基金资助项目(编号:200804590006);河南省杰出人才计划资助项目(编号:084200510003)

摘　　要：针对结构损伤识别时测试结构模态振型不完备的情况,采用了自由度凝聚方法进行模型凝聚,并给出了缩聚模型的残余力向量计算公式,证明了残余力向量对结构损伤单元的敏感性。为减小自由度凝聚及测量等因素带来的误差影响,提出了一种改进的残余力向量法。该方法首先通过测试损伤结构多阶模态得到残余力向量,并计算相对于损伤前结构的残余力向量得到残余力向量差矩阵,选取向量差矩阵各行元素中最大绝对值组成改进的残余力向量。损伤识别时,先运用改进的残余力向量确定可能损伤单元,再运用筛选法计算单元损伤程度。数值仿真算例说明,采用该方法只需结构的前几阶低阶频率和振型,就可以快速准确地识别出结构的损伤,显示了该方法具有较好的抗噪性。The method of freedom condensation was adopted to condense the computational model when the modal data were insufficient to identify the structural damages,and a formula was given to calculate the residual force vector of a reduced model. It was proved that the residual force vector was sensitive to the damaged element. An improved residual force vector method was presented to decrease the error influence caused by condensation and measurement. Firstly,the damaged structure was measured to obtain the residual force vector matrix. Then the matrix was compared with the one of undamaged structure to get the difference matrix. The biggest absolute value in each row of the difference matrix formed the improved residual force vector. The improved residual force vector was defined to locate the suspected damaged elements preliminarily. Then the damage degree was estimated by the screening method. The numerical simulation shows that only several of the previous natural frequencies and modes are needed to detect the damage quickly and accurately,and the method has a better anti-noise capacity.

关 键 词：损伤识别 残余力向量 模型缩聚 噪声 

分 类 号：TU311.3[建筑科学—结构工程] TH113[机械工程—机械设计及理论]