结构振动响应优势模态选取方法研究

摘要

基于Abaqus/Standard有限元软件模态贡献量插件MCF,对结构振动响应优势模态的选取方法进行研究.首先,通过模态贡献量频域曲线图的特性分析,提出频域峰值法和全频段法2种优势模态选取方法;进而,通过对悬臂梁振动性能及模态贡献量进行分析,分别根据以上2种方法选取了优势模态,对优化优势模态阻尼比对结构振动抑制效果进行对比,发现优化由全频段法所得到的优势模态阻尼比对降低整体振动响应的效果更为明显.最后,讨论了模态位移等因素对模态贡献量的影响规律.%Based on modal contribution factors plug in Abaqus/ Standard, the method of choosing the dominant mode of structural vibration response is studied. First, through the characteristic analysis of frequency domain curve of modal con-tribution factors, two methods of frequency domain peak method and full band method are proposed. In addition, by analyz-ing the vibration performance and modal contribution of the cantilever beam, according to the above two methods to select the dominant mode respectively, and the effect of the optimized dominant mode damping ratio on the structural vibration suppression is comparedand it is found that the optimal modal damping ratio obtained by full-band method is more effective in reducing the overall vibration response. Finally, the influence of modal displacement and other factors on modal contribu-tion is discussed.