结构损伤识别的参数反演方法研究  

Parameter Inversion Method for Detecting Damage of Structure with Input Completely Unknown

作　　者：吴子燕[1] 林湘[1] 张彬[1] 闫云聚[1] 

机构地区：[1]西北工业大学力学与土木建筑学院,陕西西安710072

出　　处：《西北工业大学学报》2007年第6期860-863,共4页Journal of Northwestern Polytechnical University

基　　金：国家高技术研究发展计划(863计划)(2006AA04Z437)资助

摘　　要：研究了未知输入条件下非线性参数系统的识别问题,通过引入广义逆,直接得出系统参数的极小范数最小二乘解,改进了全量补偿算法,提高了计算效率,使未知输入条件下系统参数反演理论进一步完善。该方法不仅能识别损伤程度,而且能确定损伤位置,思路清晰,易于编程。数值算例验证了该方法的参数识别精度,具有广泛的工程应用背景。Aim. The detection of damage of structure with unknown input is an important but challenging research topic and it has received considerable attention recently. In this paper, we propose a way of identifying system parameters with unknown input. The consideration of Rayleigh-type proportional damping introduces a nonlinear system parameter identification problem. By using the Moore-Penrose generalized inverse, the proposed method obtains minimal norm least squares solution of the unknown system parameters and has no restriction on types of input forces to be used to excite a structure. It estimates the dynamic properties of a structure in terms of stiffness and damping at the element level in a finite-element representation. The response information can be noise-free or noise-contaminated. Through improving the ＂compensation method＂ ,this paper makes it very simple and it can be used to detect damage and precisely locate defective spot in an element. With the help of an example, whose results are given in Tables 1 and 2 in the full paper, we show preliminarily that our improved compensation method does efficiently detect damage and does locate precisely defective spot. The algorithm is expected to provide a simple and efficient system identification technique that can be used as a nondestructive defect detection procedure in the future.

关 键 词：损伤识别 未知输入 参数反演 补偿算法 

分 类 号：P315.316[天文地球—地震学]