结构损伤诊断的类柔度方法研究

【作者】 胡宇宏；

【导师】 于德介；

【作者基本信息】 湖南大学 ， 机械设计与理论， 2002， 硕士

【摘要】 工程结构在使用的过程中，由于载荷的作用将产生不同位置、不同程度的损伤。为了保证结构的安全，需要及时诊断出这些损伤的位置和损伤的大小，以便对结构使用的可靠性进行合理的评估。这是一类典型的“反问题”。本文提出了三种结构损伤诊断的方法。一种是基于类柔度矩阵差值的结构损伤诊断方法。它是利用类柔度矩阵差值作为诊断损伤的敏感因子。这种方法需要知道结构损伤前即完整结构的参数信息。在此方法基础上经过改进，提出了另一种基于类柔度拟合的结构损伤诊断方法。这种方法是用损伤系数作为诊断损伤的敏感因子。它不需要知道结构损伤前即完整结构的参数信息。第三种是基于振型拟合的结构损伤诊断方法。它也是用损伤系数作为诊断损伤的敏感因子。它也不需要知道结构损伤前即完整结构的参数信息。本文详细讨论了这三种方法，并用仿真算例说明了这三种方法的有效性和可行性。并对三种方法进行了比较。最后，将类柔度拟合法、振型拟合法与振型曲率方法和频率响应函数曲率方法进行了对比。更多还原

【Abstract】 During operation of engineering structure, damages of different degrees and at different parts will appear due to action of the loading. To guarantee the safety of the engineering structure, we need checking out the positions and dimensions of these damages in order to conduct a reasonable estimate of the reliability of structure operation.This is a typical "inverse problem" .This paper put forward three kinds of structural damage detection methods. One is the diagnosis method of structure damage based on the differeance of analogous flexibility matrix,which takes the difference of analogous flexibility matrix as the sensitive factor of diagnosing damages. Parameter information of structure prior to structure damages is needed for method of this kind. Based on this method, another diagnosis method of structure damages that based on analogous flexibility polyfit is put forward.It takes the damage index as the sensitive factor of diagnosing damages, and it does not need the parameter information of structure prior to structure damage. The third method is the diagnosis method of structure damage based on mode shape polyfit. It also takes the damage index as the sensitive factor of diagnosing damages, and it also does not need the parameter information of structure prior to structure damage. This paper discusses in detail the three methods and explains their efficiency and feasibility by using simulation calculation examples. And meanwhile , it conducts a comparison of the three methods. Finally, the analogous flexibility polyfit method and the mode shape polyfit method are compared with two other relevant methods-the mode shape curvature method and the frequency response function curvature method.更多还原