Electromagnetic emission-microseismicity coupling evaluation method for rockburst

Field investigations and theoretical studies show that the dynamic damage of the coal and rock system is characterized by static-dynamic coupling loads. During the preparation and development of rockburst the electromag- netic emission can represent energy accumulation while microseismic events represent the output of energy which in- dicates microseismicity has a duality of energy release and dissipation. So it is unscientific if the electromagnetic e- mission strength which stands for the energy accumulation and microseism energy that presents energy release are separately used as the criterion for rock burst forecast. Based on energy principles the precursory rules of rock burst are studied in this paper combining with the electromagnetic emission and microseismic monitoring method,the cou- pling evaluation system was established based on the monitoring results of a specific rockburst colliery. The results show the precursory rules that the elec-tromagnetic emission strength is much higher than normal and micro-seismic energy is continuously lower as well as the activity number appears an increase tendency. Rock burst will not occur if the micro-seismic activities are on the steady energy release estate even though the electromagnetic emission strength is higher.