结构模态的分区测试方法研究

Research on the approach to structural modal test in segments

大型复杂结构通常有尺度大、刚度高、阻尼衰减明显等特性,对其进行模态试验难以激起整个结构振动,导致测试信噪比低。本文提出带过渡区的分区模态测试方法有效提高模态测试信噪比,并提出振型可信度参数,预判分区模态测试结果。模型实验验证了本文所提出方法的可靠性和可行性,为工程中应用分区模态测试奠定了技术基础。

Complicated structure with a large size always has the characteristics of large scale,high stiffness and distinct damping attenuation.It is difficult to drive global vibration on it in modal test.This leads to a low Signal-to-Noise Ratio.A new approach to modal test in Segments with transitional sections,which can improve SNR effectively,is presented in this article.A new parameter named mode reliability is presented to predict the quality of result of modal test in Segments.Model experiment demonstrates the reliability and feasibility of this approach,which lays the technical foundation of the application of modal test in Segments in engineering.