Analysis of frequency characteristics of infrasonic signals in coal specimens burst based on wavelet packet transform
WANG Yungang
WANG Qingjun
WEI Jianping
LEI Dongji
Abstract：Infrasonic wave technology is expected to become a new method to monitor and warn the dynamic disasters of coal and rock in coal mine,and the frequency characteristics of infrasonic signal are the key parameters of application research.Through the uniaxial compression test of coal specimens,the infrasonic signal monitoring system is used to collect the signals produced by the coal specimen in the process of deformation and fracture.The energy distribution characteristics of the signal were analyzed by means of wavelet packet transform.The experiment results show:(1) Wavelet packet transform can fine signal segmentation into each frequency band,and can play an role in filtering,the frequency range of the analysis.(2)There is a good correspondence between the infrasonic signals of coal specimen burst and the stress in the time,especially the infrasonic signal shows a significant mutation during stress drop.The stress drop reflects the emergence of macroscopic cracks to some extent,indicating that infrasonic signal has a good sensitivity to macroscopic cracks.(3) The frequency of the infrasonic signals of coal specimen burst are all distributed in 0 ～ 20 Hz,but mainly in 3.125 ～ 12.5 Hz and 18.75 ～ 21.875 Hz.The signal analysis method with wavelet packet transform and the frequency characteristics of the infrasonic signals of coal specimen burst can provide the study basis and reference for further research.
Keywords：infrasonic wavewavelet packet transformuniaxial compressioncoal or rock dynamic disaster
Publication Date：2018-03-02
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 1-7 )