Analysis and Research on Microseismic Signal Characteristics and Energy Change of Working Face in Liyazhuang Mine

Abstract

To provide a certain support for the prediction of the rockburst and setting of the threshold, the SOS microseismic monitoring system is used to remotely, real-time, dynamic and automatic monitoring of the seismic signal of the 2-228 working face of Liyazhuang coal mine. And the original signal of the microseismic is processed by the window Fourier transform, and the characteristics of the microseismic waveform and spectrum of different energy levels are analyzed. The results show that there are different characteristics of waveform and spectrum corresponding to signals at different energy levels. The high amplitude, low and centralized main frequency, long duration of signal, coda waves developing obviously than head wave and slow attenuation are the typical characteristics of strong mine earthquake. With the decrease of mine earthquake energy, the vibration attenuation rate gradually becomes faster, and the duration of the signal being shorter, the development of the head wave being obvious, the amplitude of velocity decreasing correspondingly, but the rate of amplitude decreasing gradually slows down, and the main frequency is gradually spread from concentration to diffusion, while the frequency distribution range is affected rarely. The research results can provide a scientific basis for setting the threshold of shock pressure prediction index and its risk prediction.