厚煤层小煤柱沿空巷道围岩控制技术应用

Application of surrounding rock control technology for gob-side entry with small coal pillar in thick coal seam

针对黄陵二号煤矿区段煤柱宽度为35m时,煤炭资源回采率低,巷道维护成本高的问题,采用理论计算、数值模拟和现场实测的研究方法,确定了301运输巷留小煤柱沿空掘巷时煤柱合理宽度。分析认为,煤柱宽度为10m和15m时,围岩变形和应力相对较小,综合考虑煤柱稳定性、承载能力、工作面回采率和工作面实际条件,确定煤柱合理宽度为17.5m。现场应用结果表明,采用“锚网索梁”支护后,巷道掘进期间顶底板和两帮相对移近量最大值分别为29.01mm和36.76mm,无网兜、片帮和底鼓现象发生,巷道围岩变形得到有效控制。

Aiming at the problems of low coal resource recovery rate and high roadway maintenance cost when the coal pillar width of Huangling No.2 mining area section is 35 m,by using theoretical calculation,numerical simulation and field measurement,the reasonable width of coal pillar is determined when gob-side entry driving with small coal pillar in 301 transportion roadway.The analysis shows that when the width of coal pillar is 10 m and 15 m,the deformation and stress of surrounding rock are relatively small.Considering the stability of coal pillar,bearing capacity,recovery rate of working face and actual conditions of working face,the reasonable width of coal pillar is determined to be 17.5 m.The field application results show that after the support of "anchor mesh cable beam"is adopted,during the roadway tunneling period,the maximum relative displacement of the roof and floor and the two sides are 29.01 mm and 36.76 mm respectively,there is no net pocket,wall caving and floor heave,and the surrounding rock deformation of the roadway is effectively controlled.