不同激励下基于SVMD的结构响应重构方法

Structural Response Reconstruction Method Based on SVMD under Different Excitations

针对基于经验模态分解(Empirical Mode Decomposition,EMD)的响应重构方法需要设置繁杂的带通滤波器参数,且无法在时域中直接重构周期激励作用下的响应等问题,提出一种不同激励下基于逐次变分模态分解(Successive Variational Mode Decomposition,SVMD)的响应重构方法。首先,分别考虑瞬态激励和周期激励两种工况,使用SVMD将传感器测得的动态响应信号分解为多个分量。其次,使用由模态分析推导出的模态转换矩阵和传递矩阵得到未测量位置的响应分量。最后,根据模态叠加法实现时域响应重构。对六层剪切框架和简支梁分别进行数值仿真和试验验证,结果表明,所提方法在使用单个传感器的条件下即可对不同激励下的结构响应实现有效重构,且对测量噪声具有一定的鲁棒性。

Aiming at the problems that the response reconstruction method based on empirical mode decomposition(EMD)needs to set complex band-pass filter parameters and cannot directly reconstruct the response under the action of periodic excitation in the time domain,a method of response reconstruction based on successive variational mode decomposition(SVMD)under different excitations was proposed.Firstly,considering the two conditions of transient excitation and periodic excitation respectively,the dynamic response signal measured by the sensors was decomposed into several components by using SVMD.Secondly,the response components at the unmeasured position's were obtained using the modal transformation matrix and transfer matrix derived from modal analysis.Finally,the time domain response reconstruction was realized using the modal superposition method.The numerical simulation of a six-storey shear frame and a simply supported beam was done and the results were verified experimentally.It is shown that the proposed method can effectively reconstruct the structural response under different excitation conditions with a single sensor,and has the robustness for measurement noise.