Research on time-frequency characteristics of microseismic signal and precursory characteristics of rockburst in Gengcun Coal Mine

Based on the microseismic monitoring data, the time-frequency characteristics of the rockburst events induced by mining in 13200 working face of Gengcun Coal Mine of Henan Energy and Chemical Industry Group Co., Ltd. and microseismic events before the rockburst events are analyzed by using fast fourier transform, wavelet packet transform and Hilbert-Huang transform. The results show that the main frequency of rockburst is within 10 Hz, and the main frequency of the microseismic event waveform before rockburst is within 100 Hz. The highest energy distribution frequency band is within 5 when rockburst occurs. The highest energy distribution frequency band of the previous three microseismic events waveforms is about 10. The instantaneous energy of the six microseismic event waveforms before rockburst is not high, indicating that there is a silent period of energy before rockburst occurs. Based on the time-frequency characteristics of rockburst events and microseismic events before rockburst, the precursor characteristics of rockburst are obtained. The main frequency of the microseismic event waveform is within 100 Hz, the highest energy distribution frequency band is within 10, and the instantaneous energy is less than 1.5.