基于振动测试和有限元法的泵站厂房模态识别

Modal identification of pumping station building based on vibration test and finite element method

模态参数识别在工程领域的应用非常广泛,相关研究具有重要的理论意义和实际工程应用价值。本文以某泵站厂房作为研究对象,分别采用增强型频域分解法(EFDD)和随机子空间识别法(SSI)对不同工况下的泵站厂房结构进行了模态参数识别,并与有限元法(FEM)的分析结果做了对比研究。结果表明,将EFDD和SSI方法应用于泵站厂房结构的模态识别是适用且可靠的,其中EFDD法计算速度较快,但需要拾取峰值判别特征模态,其精度受主观因素影响较大,而SSI法可自动识别相对稳定的特征模态。该结论可为实际工程应用提供参考。

Modal parameter identification is widely used in engineering field.The related research has important theoretical significance and practical engineering application value.In this paper,a pump station building is taken as the research object,and the enhanced frequency domain decomposition(EFDD)and stochastic subspace identification(SSI)are used to identify the modal parameters of the pumping station building structure under different working conditions.The analysis results are compared with the results of finite element method(FEM).The results show that the EFDD and SSI methods are reliable and applicable to the modal identification of the pumping station structure,in which the EFDD method has a faster calculation speed,but it needs to pick up the characteristic mode of the peak value,and its accuracy is greatly influenced by the subjective factors,and the SSI method can automatically identify the relatively stable characteristic mode.This conclusion provides reference for practical engineering application.