摘要
基于Bernoulli-Euler梁振动理论,以等效扭转弹簧模拟裂纹引起的局部软化效应,推导了双裂纹悬臂梁的解析特性方程,提出了识别裂纹参数的"特征方程曲线交点法"﹒通过数值模拟计算,讨论了裂纹位置与裂纹深度对梁的固有频率的影响﹒应用有限元软件ANSYS对双裂纹悬臂梁进行模态分析,将得到前3阶固有频率作为实测参数,代入双裂纹悬臂梁的特征方程,通过绘制特征方程曲线图,通过交点确定第2条裂纹参数,最后利用数值算例验证了该方法的有效性﹒
In this paper, a method is presented to facilitate the computation of dynamic properties of cantilever beams with any number of cracks. Based on the Bernoulli-Euler theory for beam, an analytical the local effect of ＂softening＂ at the location can be simulated by an equivalent rotational spring, the characteristic equation of cantilever beam with two cracks is derived, a method for crack identification based on the ＂point of intersection curves of the characteristic equation method＂. The effects of crack position and depth on the first three natural frequencies of a beam are investigated by the numerical example. The modal analysis of the double-crack cantilever is carried out by using of ANSYS, as a first third-order natural frequency of the measured parameters into the characteristic equation of the double-crack cantilever beam, which intersection is a second crack, Finally, the numerical examples verify the effectiveness of the method.
出处
《湖南城市学院学报（自然科学版）》
CAS
2009年第3期1-4,共4页
Journal of Hunan City University:Natural Science
关键词
多裂纹悬臂梁
扭转弹簧
特征曲线交点法
损伤识别
固有频率
Cantilever beam with multiple cracks
point of intersection curves of the characteristic equation method
rotational spring
damage identification
natural frequency
