坚硬顶板薄煤层开采沿空留巷关键技术研究

Key technology of gob-side entry retaining in thin coal seam with hard roof

为了确定坚硬顶板下薄煤层沿空留巷切顶钻孔爆破参数及围岩控制方案,以山东枣矿滨湖煤矿21602工作面运输巷为工程背景,运用理论分析、数值模拟及现场实测的手段进行了研究,将沿空留巷划分为三个阶段,并给出了相应的巷道围岩支护方案。现场应用结果表明:合理的钻孔爆破高度为4.5 m,切顶角度为70°;现场实施爆破后,留巷稳定后顶板累计变形量为118 mm,底板累计变形量为344 mm,实体煤侧累计变形量为402 mm,能满足留巷后期使用要求。

In order to reasonably determine the surrounding rock control and drilling-blasting parameters of gob-side entry retaining in thin coal seam under hard roof,taking the transportation roadway in 21602 working face of Binhu Coal Mine in Zaozhuang,Shandong Province,as the engineering background,the key parameters of gob-side entry retaining with roof cutting were thoroughly studied by means of numerical simulation and field measurement.Considering the structural evolution of roadway surrounding rock,the gob-side entry retaining was divided into three stages,and the corresponding roadway surrounding rock support scheme was given.The results show that the reasonable drilling and blasting height is 4.5 m and the cutting angle is 70°;after the blasting,the accumulated deformation of the roof,the floor and the side of the solid coal are 118,344 and 402 mm,respectively,after the roadway is stabilized,which can meet the requirements of the later use.The relevant research results were applied in the 21602 working face,providing a reference for the implementation of gob-side entry retaining under the same conditions.