基于EEMD和ARMA算法的某大型斜拉桥的模态参数识别

Modal Parameter Identification of a Large Cable-stayed Bridge Based on EEMD and ARMA Algorithm

识别桥梁结构模态参数是结构健康监测和振动控制等研究及工程实践中的一个重要环节。基于EEMD和ARMA算法的模态参数识别技术,利用EEMD分解对原始加速度信号进行分析,然后对所得的IMF进行信号重构。将重构的加速度信号作为ARMA算法的输入,进行模态参数识别,得到了某大桥的前6阶频率,并分析了每阶频率1d内的变化波动情况。通过对比分析每阶频率与实际值的差距,表明该识别方法能有效识别该斜拉桥频率。

Modal parameter identification of bridge structure is an important part of the study of structural health monitoring,vibration control and engineering practice.The proposing of modal parameter identification based on EEMD and ARMA algorithms shall use EEMD decomposition to analyze the original acceleration signal,and make signal reconstruction for IMF.The acceleration signal which is reconstituted will be the input of ARMA algorithm to identify the modal parameters and obtain the frequencies of the first six orders,and analyze the changes of volatility in each order within a day.Finally,getting the difference between the frequency of each order and actual value by contrastive analysis,it can be found that the proposed identification method can effectively identify the frequency of the cable-stayed bridge.