摘要
煤矿开采中常用全部垮落法管理工作面采空区顶板,当工作面上覆岩层存在坚硬顶板时,一旦顶板悬顶重量达到自身承载极限时,极易发生大面积冒顶事故,造成设备损毁和人员伤亡.针对雅店煤矿工作面回采时上覆坚硬顶板难垮落,长距离悬顶问题,采用定向长钻孔区域压裂技术,打破坚硬顶板在垮落时出现的整体性、瞬时性问题.结果表明,压裂后微震能量同比下降约15％,压裂中期、后期各自30 d内高能事件数量分别下降67％和11％;采动影响范围缩小,压裂区域整体来压步距明显降低,压裂区域的来压强度减小.保障工作面的安全高效生产,形成适合雅店煤矿地质条件下的区域卸压技术体系.
Abstract
Total caving method is usually adopted to manage goaf roof in coal mining.When the overlying on the working face is hard roof,once the weight of the suspended roof reaches its load-bearing limit,a large area of roof collapse accidents are easy to occur,which is easy to cause equipment damage and casualties.In order to solve the problem that hard roof over-lying in Yadian coal mine is difficult to collapse and long distance hanging roof during mining,the fracturing technology of directional long drilling area is adopted to break the integrity and instantness of hard roof during collapse.The results showed that:the microseismic energy after fracturing decreased by about 15％compared with the same period last year.The number of high-energy events decreased by 67％and 11％in the middle and late stages of fracturing,respectively.The range of mining influence is reduced.The fracturing zone as a whole has significantly reduced weighting step spacing.Weighting strength decreases in the fracture zone.It ensures the safe and efficient production of the working face and forms a regional pressure relief technical system suitable for the geological conditions of Yadian coal mine.
维普
万方数据