Effect of deep hole blasting for rock burst prevention and control in suberect and extremely thick coal seams

In order to prevent and control the rock burst in suberect and extremely thick coal seams, deep-hole blasting on the ground was adopted to conduct presplit blasting in rock pillars between coal seams, ground EH-4 detection method and down-hole transient electromagnetic(TEM) detection method were used to detect the physical and mechanical structure of rock pillars before and after blasting and to analyze the pressure relief effect. According to the detection of EH-4, the rock pillar structure was destroyed obviously after deep-hole blasting, at the level +550 m~+650 m, the resistivity contour of the rock pillar was developed from suberect to subhorizontal, and the apparent resistivity was concentrated at 150~250 Ω·m and is obviously higher than that in the non blasting area; from TEM, rock fractures increased after deep-hole blasting, the apparent resistivity in the area of 20~90 m before the detected area increased from 25~86 Ω·m to 84~216 Ω·m, and high resistivity anomaly area also occurred. It can be concluded that the crushing effect of rock pillar is better after deep-hole blasting, and the elastic energy accumulated in the rock pillar can be released, and pressure relief effect is quite obvious, which effectively reduces the risk of rock burst.