基于谐响应的弹性悬臂梁裂纹识别分析

针对弹性悬臂梁的裂纹识别问题,探讨了谐响应分析在含裂纹梁损伤识别中的应用。首先结合连续介质弹性梁动力学方程和有限元方法,建立了含裂纹梁的受迫振动方程。然后,基于Abaqus平台建立了若干种含V型表面裂纹的悬臂梁有限元模型,在此基础上通过施加外部激励进行谐响应理论分析。最后,探讨了裂纹几何参数和加载位置对谐振频率及谐响应幅值的影响。结果表明,裂纹深度、裂纹位置、裂纹数量以及加载位置对谐响应变化规律有明显影响,为悬臂梁的裂纹识别提供了思路。

Analysis on Crack Identification of an Elastic Cantilever Beam by Harmonic Response

According to the problem of crack damage in the elastic cantilever beam, a damage identification method of cracked beam was discussed by harmonic response. Combined with the elastic continuum beam dynamics and the finite element method, the forced vibration equation of the cracked beam was set up. Then several finite element models of the cantilever beam with V type crack were constructed, and the harmonic response analysis were carried out through acting external force on the models to discuss the relation of the crack parameters and the harmonic response. The impacts of loading position on the response magnitude were also discussed in the end. Results indicate that the impacts of crack depth, crack position, crack number and loading position on the change law of harmonic response are obvious, and it provides a new idea for crack identification of cantilever beam.