Elastic Wave Denoising in the Case of Bender Elements Type Piezoelectric Transducers

Abstract

The accuracy of the wave signal is key to studying physical information inside the soil using bender-element-type piezoelectric transducers. There is too much noise during the elastic wave signal collected by bender elements, which is caused by factors such as fluid current and infiltration. At present, the mainstream method is the superposition method, which superposes multiple tested waveform data to obtain a clear waveform. However, the superposition method is limited by the number of signals during the collection, and the denoised waveform still contains high-frequency noise. A combination method combining superposition and the wavelet threshold is proposed in this work to improve the accuracy of the elastic waveform signal. Three different signal denoising simulation tests and one model box test are conducted to verify the method’s feasibility from two aspects. The results show that the combined method can effectively remove high-frequency noise and display clear waveforms based on overcoming the number of signals. This work provides a new means of signal denoising in the case of studying soil properties by bender-element-type piezoelectric transducers.

Chaotic Characteristic Analysis of Spillway Radial Gate Vibration under Discharge Excitation

“…The common threshold function is divided into soft and hard threshold functions [25,26], which are given in Equations ( 19) and (20), respectively:…”