高强度开采条件下巷道切顶护巷技术研究

针对厚煤层、高强度开采条件下的沿空巷道围岩变形严重、维护困难的问题，以布尔台矿42203工作面为研究背景，采用理论分析和数值模拟的方法研究沿空巷道围岩变形特征，提出采用定向预裂爆破技术进行切顶卸压，以保护临近采空区的巷道。基于不同切顶高度条件下的巷道状况模拟结果发现，切顶后明显改善了巷道围岩应力环境，并确定合理切顶高度为21 m，定向预裂爆破钻孔间距为16 m，装药密度12 kg/m，钻孔角度向采空区方向偏15°、向回采帮偏5°；最终在现场进行试验。结果表明，切顶后巷道两帮移近量86 mm，顶板下沉量55 mm；采用切顶护巷技术对沿空巷道起到了较好的保护作用，能够满足安全生产需要，同时也为类似矿井切顶卸压工程试验的实施提供借鉴。

Research on roadway roof cutting and roadway protection technology under high strength mining conditions

In view of the serious deformation and difficult maintenance of the surrounding rock of the god-side entry retaining under the condition of thick coal seam and high-intensity mining，taking the No.42203 working face of Buertai Mine as the research background，the deformation characteristics of the surrounding rock of the gob-side entry retaining are studied by using the methods of theoretical analysis and numerical simulation，and the directional presplitting blasting technology is proposed for roof cutting and pressure relief to protect the roadway near the goaf.Based on the simulation results of roadway conditions under different roof cutting heights，it is found that the stress environment of roadway surrounding rock is significantly improved after roof cutting，and it is determined that the reasonable roof cutting height is 21 m，the drilling spacing of directional presplitting blasting is 16 m，the charge density is 12 kg/m，and the drilling angle deviates 15° to the goaf and 5° to the stope；finally，the test shall be carried out on site.The results show that after roof cutting，the two sides of the roadway move close by 86 mm and the roof subsidence is 55 mm.The roof cutting roadway protection technology plays a good role in protecting the gob-side entry retaining ，which can meet the needs of safety production.At the same time，it also provides a technical reference for the implementation of roof cutting and pressure relief engineering test in similar mines.