大倾角综放工作面爆破卸压后高应力区域的形成和处置

Formation and Disposition of High Stress Region in Large Dip Angle Thick Coal Seam Fully Mechanized Working Face After Blasting and Pressure Relief

针对王家山煤矿47407大倾角特厚煤层综放工作面矿压动力显现危险预测区域内两道爆破卸压后,在该区域回采期间工作面中段(圆弧段)出现高压力显现的问题,通过对两道爆破前后工作面的压力分布进行现场观测,并基于弹塑性岩体理论对采场上覆煤岩层建立模型,根据UDEC数值模拟分析结果,得出工作面中段(圆弧段)上方存在的爆破卸压盲区是造成"高应力传递区域"的直接原因。基于此,在下口向外15 m处起对工作面中段顶部煤岩体实施了倒"八"字孔爆破卸压后,成功对高应力传递区域进行解危,阻断了高应力传递路径,此后在工作面两道爆破卸压后的矿压动力显现预测区域回采期间中段压力显现问题消失,确保了安全生产。

After blasting and pressure relief in mine pressure dynamic dangerous prediction region of Wangjiashan Coal Mine 47407 large dip angle thick coal seam fully mechanized working face mining roadway,there is a problem of high pressure appearance in the middle section of the working face（ arc section） during mining. Through the field observation of pressure distribution of the working face before and after blasting and based on the theory of elastic-plastic,overlying coal rock model is established; through UDEC numerical simulation results,it is concluded that there is a direct cause of ＂ high stress transfer area＂ due to the existence of blind zone in the middle part of the working face（ arc section） at last. Based on this,after designing the inverted ＂ 八＂ blasting hole in the lower exit of working face for blasting on coal rock mass above the working face,we succeed in getting rid of danger for high stress transfer area,cut off high stress transfer path. Since then,after blasting and pressure relief in the work face of mining roadway in prediction area during production,the problem of strata behaviors in the middle part of the working face disappeared,which ensured safety production.