裂纹悬臂梁的扭转弹簧模型及其实验验证

Analysis and Experiments of Cracked Cantilever Beam Using Torsional Spring Model

将含裂纹悬臂梁转化为由扭转弹簧联接两段弹性梁构成的连接体 ,得到理论计算含裂纹梁振动频率的特征方程。确立了求解裂纹梁固有频率的数值计算流程 ,计算得到了裂纹深度和位置变化时裂纹悬臂梁振动固有频率的变化规律。进行了裂纹悬臂梁的弯曲振动台架实验 ,验证了本文提出的扭转弹簧模型及固有频率数值计算方法的有效性。

The vibration characteristics of a cantilever beam with a single crack are investigated using a torsional spring model.Due to the localized crack effect,the beam can be simulated by two segments connected by a massless spring.Relations between the changes in natural frequencies and mechanical impe dance and the location and depth of the crack are obtained.The resulting characteristic equation for the natural frequencies can be solved numerically and the effectiveness of the method is proved by experiments.