近直立特厚煤层深孔爆破防治冲击地压效果检测

为了对近直立特厚煤层冲击地压进行防治，采用地面岩柱深孔爆破方法对煤层间岩柱进行预裂爆破，并采用地面EH-4探测法和井下瞬变电磁探测法对爆破前后岩柱体的物理力学结构进行探测，对卸压效果进行分析。EH-4探测表明，深孔爆破后岩柱结构破坏明显，在+550~+650 m水平范围时，岩柱体的电阻率等值线由近直立向近水平发育，视电阻率值主要集中在150~250 Ω·m，明显高于未爆破区域；井下瞬变电磁探测表明，深孔爆破后岩柱裂隙增大，探测区域前方20~90 m，视电阻率值从爆破前的25~86 Ω·m增加到爆破后的84~216 Ω·m，出现高阻异常区域。深孔爆破后岩柱破碎效果较好，岩柱体内积聚的弹性能得到释放，卸压效果明显，有效降低了冲击地压发生的危险性。

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.