Bridge Monitoring Signal Noise Reduction Method for EMD Joint Improvement of Wavelet Threshold

When the bridge conducts status assessment and health monitoring, the obtained bridge signals are susceptible to the interference of the external environment and are difficult to reflect the true response of the bridge structure. Based on the bridge monitoring signal noise reduction method for EEMD to improve the wavelet threshold. This method first uses EEMD to perform adaptive decomposition of the signal containing noise, then removes the modes with small variance contribution rate, and finally performs the wavelet threshold denoising of the remaining modes to reconstruct the real signal after denoising. On the simulated signals, the results show that the noise reduction method of EEMD can filter the interference noise signal effectively, and the noise effect is better than the single improvement, EMD and EMD denoising, and the research results can provide meaningful reference for the bridge signal denoising processing.