摘要
研究了裂纹扩展引起的结构柔度变化以及裂纹界面接触对弹性梁振动特性的影响。基于断裂力学和能量原理推导了含横向裂纹弹性梁的局部柔度模型,分析了常见形式裂纹均匀梁的局部柔度,给出了相应的无量纲柔度系数计算公式;结合梁的弯曲振动方程,探讨了含裂纹悬臂梁的振动特性。算例表明:裂纹形式对弹性梁的柔度影响明显,裂纹界面接触会引发参数振动,界面滑动摩擦阻尼对稳定梁的振动响应具有重要作用。
Based on the local flexibility of an elastic beam is changed with the crack growth, impacts of contacting in crack interface on the vibration characteristic of a cracked beam are studied. Firstly, fracture mechanics and energy theory is employed to derive the local flexibility model for an elastic beam with transverse crack. Then the local flexibility coefficient is analyzed for an elastic beam with different modes of crack and the non-dimension local flexibility coefficient is given. Through the vibration equation of an elastic beam, the vibration characteristic of a cantilever cracked beam is discussed in the end. Results indicate that the crack modes are sensitivity to the local flexibility coefficient, crack close will produce parametric vibration and the interface friction is very important to the vibration amplitude.
出处
《失效分析与预防》
2013年第5期259-263,共5页
Failure Analysis and Prevention
基金
国家自然科学基金(51265040)
江西省自然科学基金(20122BAB216027)
关键词
结构裂纹
弹性梁
振动特性
structure crack
elastic beam
vibration characteristic