基于环境激励的双曲拱桥模态参数识别

Modal parameter identification of hyperbolic arch bridge based on ambient excitation

为了比较现有模态参数识别算法的优劣,分别采用随机子空间(SSI)法、特征系统实现算法(ERA)、复指数法、随机减量法(ITD)、STD法、ARMA模型时间序列法对一钢筋混凝土双曲拱桥的模态参数进行识别。结果表明:SSI法、ERA法、复指数法、ITD法、STD法、ARMA模型时间序列法,准确度均较高,可用于实际工程结构模态频率识别;几种时域模态参数识别方法的阻尼比识别结果离散性较大,无法准确估计结构的阻尼比。

In order to compare the pros and cons of the existing modal parameter identification algorithms,Stochastic subspace identification(SSI)method,eigensystem realization algorithm(ERA),Complex Exponential Method,Ibrahim Time Domain(ITD),STD method,and ARMA model time series are used Method to identify the modal parameters of a reinforced concrete double arch bridge.The results show that:SSI method,ERA method,complex exponential method,ITD method,STD method,ARMA model time series method,all have high accuracy,and can be used for modal frequency identification of actual engineering structures;several methods of modal parameter identification in time domain The results of the identification of the damping ratio are relatively discrete,and the damping ratio of the structure cannot be accurately estimated.