关于悬臂梁振动特性的损伤灵敏度的研究

ON THE DAMAGE SENSITIVITY OF DYNAMIC PROPERTIES OF CANTILEVER BEAMS

基于振动特性的损伤识别方法是研究者十分关注的问题。为了确保这类方法的有效性,有必要研究振动特性对结构损伤的敏感性。为此,该文推导了有一处损伤的悬臂梁的振动特性的解析解,并在此基础上详细讨论了不同的振动特性对损伤的敏感性。分析结果表明:当梁中某段存在损伤时,结构的频率和模态不会发生太大的变化;而转角模态和曲率模态在损伤区域会发生明显的突变。这些结果以及文中的讨论对相关领域的研究者有一定的参考价值。

Damage detection methods based on vibration responses intensively interest relevant researchers. To ensure the applicability of these methods, it is important to study the sensitivity of dynamic properties to structural damage. For this purpose, this paper presents an analytic solution of dynamic properties of cantilever beams with certain damage. Based on this solution, the sensitivities of different dynamic properties to damage are discussed. It is observed that the natural frequencies and mode shapes do not change significantly when damage accumulates in one section of the beam; while the mode of rotation angle and curvature mode suffer abrupt change near the damaged region. These results and discussions could provide some references for the researchers working in this field.