基于围岩应力-裂隙特征的封孔深度优化研究

Study on Optimization of Hole Sealing Depth Based on Stress-fissure Characters of Surrounding Rock

钻孔的封孔深度直接影响到整个抽采系统的效率发挥,其合理的封孔深度是确保高效抽采的关键。以底抽巷穿层抽采钻孔为研究对象,采用数值计算和超声波探测法对钻场围岩破裂范围进行了分析实测,基于钻进速率曲线分析得到了围岩应力集中边界位置。通过基于抽采效果对比实验确定了最佳封孔深度位置。结果表明,穿层抽采钻孔封孔深度应大于围岩应力集中区边界。

The hole sealing depth directly affects the gas drainage efficiency of the whole system, its reasonable sealing depth is the key to ensure efficient extraction. Taking the through beds holes in floor drainge roadway as the research object, the fracture range in the surrounding rock of the drilling field was detected and analyzed by numerical simulation and the ultrasonic detection.The distribution of stress concentration zone was detected by velocity analysis of the drilling process. The gas drainage tests based on different sealing depth reveal that the shortest sealing depth is 10 m, which should exceed the boundary of the stress concentration zone.