Study On Micro-seismic Signal Characters About Coal And Rock Fracture Of Blasting Tunneling

The safe production of coal mine is seriously threatened by coal and rock dynamic disasters. The mechanism of coal and rock dynamic disasters isn’t clear, But many scholars agree that the occurrence of coal and rock dynamic disasters is due to the dynamic process of the internal energy of coal and rock accumulation and release made the coal and rock broken. The Geophysical method is a new method to predict coal and rock dynamic disasters. Micro-seismic monitoring technology is a method to monitor the stability of coal and rock by observation, analysis the micro-seismic signals during the rupture process of coal and rock. It has the characteristics of continuous and dynamic monitoring and has been widely used in our country.The study based on the blasting test at coal roadway tunneling in Guizhou Province Linhua mine of second mining area, the micro-seismic signals are collected by the micro-seismic monitoring system which imported from ESG company of Canada. The micro-seismic signals are analyzed by Spectrum analysis and Wavelet packet transform,It is draw that the coal drop signals frequency range is 375~500Hz, roof pressure signals frequency range is 500~625Hz, coal drop pillar pressure signals frequency range is625~750Hz, ventilation opening signals frequency range is 0~375Hz, construction explosion hole signals frequency range is 500~875Hz, clearing coal signals frequency range is 500~875Hz, construction rock bolt hole signals frequency range is 500~875Hz,Through analysis micro-seismic signals of stress adjustment caused by coal and rock fracture, it is reveals the process of coal and rock stress adjustment after blasting, thus to provide a foundation research for predicting of coal and rock dynamic disasters.