结构健康监测中的损伤检测技术研究进展

PROGRESS OF DAMAGE DETECTION FOR STRUCTURAL HEALTH MONITORING

对结构健康监测研究中的结构损伤检测方法及其特点进行了介绍。从基于结构模态分析的方法和基于结构动态试验信号处理的方法两方面,阐述了结构健康监测中的损伤检测方法及其最新研究进展。基于结构模态分析的结构损伤检测方法是针对整个结构的检测,使用的模态都限于低阶模态范围内,所检测的结构应容易建立有限元模型,便于进行响应预测。基于结构动态试验信号处理的损伤检测方法通常是针对结构局部构件的损伤检测,不需要对结构进行有限元建模,而直接从测试的动态响应信号中提取表征结构损伤的特征参数。文中提出了对比性损伤检测方法和非对比性损伤检测方法的概念,并对结构损伤检测中常用的信息传感与处理技术进行了论述,指出了结构损伤检测研究中应该考虑的传感器布置问题。提出了将损伤信息的主动检测与被动检测相结合进行损伤程度判断和剩余寿命估计等问题是有待进一步深入研究的课题。

This paper discusses the current approaches of structural damage detection in structural health monitoring (SHM) and their respective features. The damage detection methods are classified into two cate- gories, one is based on the theory of modal analysis and another is based on signal processing of the structural dynamic tests. The damage detection method in the first category uses low order vibration modes of the structure and requires dynamic testing on the whole structure, the dynamic responses of the structure can be calculated from its finite element model. In the second category, the damage detection method is usually used to detect damage of structural components by the damage characteristic parameters extracted from measured dynamic response data without finite element modeling of the structure. The concepts of comparative method and non-comparative method of damage detection are proposed in this paper. In the comparative damage detection method, the characteristic parameter of the intact structure is required to serve as the comparing template, while the non-comparative method determines the damage state directly from the measured dynamic response of the structure with the help of some physical and engineering knowledge. The problems of signal sensing and processing techniques and the collocation of sensors used in damage detection are also discussed in this paper. The approach to quantify damage severity and to estimate residual life of the damaged structure by combined active and passive detecting techniques is proposed.