Geotechnical engineering blasting: a new modal aliasing cancellation methodology of vibration signal de-noising

In the present study of peak particle velocity (PPV) and frequency, an improved algorithm (principal empirical mode decomposition, PEMD) based on principal component analysis (PCA) and empirical mode decomposition (EMD) is proposed, with the goal of addressing poor filtering de-noising effects caused by the occurrences of modal aliasing phenomena in EMD blasting vibration signal decomposition processes. Test results showed that frequency of intrinsic mode function (IMF) components decomposed by PEMD gradually decreases and that the main frequency is unique, which eliminates the phenomenon of modal aliasing. In the simulation experiment, the signal-to-noise (SNR) and root mean square errors (RMSE) ratio of the signal de-noised by PEMD are the largest when compared to EMD and ensemble empirical mode decomposition (EEMD). The main frequency of the de-noising signal through PEMD is 75 Hz, which is closest to the frequency of the noiseless simulation signal. In geotechnical engineering blasting experiments, compared to EMD and EEMD, the signal de-noised by PEMD has the lowest level of distortion, and the frequency band is distributed in a range of 0–64 Hz, which is closest to the frequency band of the blasting vibration signal. In addition, the proportion of noise energy was the lowest, at 1.8%.