特厚煤层综放工作面防冲煤柱宽度优化

为研究强冲击倾向性特厚煤层综放工作面区段煤柱合理宽度，对华亭煤矿250102工作面频发的冲击地压现象进行分析，发现250102工作面20m区段煤柱内存在着极易诱发冲击地压的应力条件，具有典型的煤柱型冲击地压特征。采用数值模拟和理论计算的方法对2501采区工作面区段煤柱合理宽度进行模拟计算。研究表明：当煤柱宽度为5m时，应力集中系数最低，为1.14，冲击危险程度较低|当煤柱宽度为20m时，应力集中系数达到最高，为3.40，冲击危险程度达到最大|当煤柱宽度为25m以上时，应力曲线由单峰转化为双峰，煤柱由小煤柱的屈服阶段进入到大煤柱的承载阶段，冲击危险程度在不断降低|理论计算得出适合2501采区工作面区段煤柱宽度为5.64m，与数值模拟结果较为吻合。2501采区后续工作面均采用6m宽的区段煤柱，经实践验证，该宽度的区段煤柱对华亭煤矿冲击地压的防治效果较好。

Coal Pillar Width Optimization for Preventing Rock Burst of Fully Mechanized Caving Face in Extra Thick Seam

In order to study the reasonable coal pillar width of fully mechanized caving face in extra thick seam with strong bursting liability, some outburst phenomenon frequently occurring along the coal pillar of the 250102 working face in Huating coal mine was analyzed. It is found that 20 m coal pillar of 250102 working face is under the stress conditions which can easily induce coal pillar type rock burst. By means of numerical simulation and theoretical calculation, the reasonable width of coal pillar in 2501 mining area was studied. The results show that: the stress concentration coefficient, when the coal pillar width is 5 m, is the lowest and it is 1.14, which indicates the low rock burst risk. When the coal pillar width is 20 m, the stress concentration coefficient reaches the highest and it is up to 3.40, and the corresponding rock burst risk reaches the highest. When the coal pillar width is more than 25 m, the stress curve in the pillar changes from a single peak to a double peak, and the coal pillar is in the bearing stage of a wide coal pillar instead of the yield stage of a narrow pillar. Moreover, the rock burst risk is increasingly decreased with the increasing of pillar width. The theoretical width of coal pillar 2501 mining area is 5.64 m and it is well consistent with the numerical simulation results. 6 m coal pillar was adopted in subsequent working face in 2501 mining area and it has a good effect on the prevention and control of rock burst risk based on the field monitoring. The study results are of significance for the prevention and control of rock burst in other coal mines with similar geological conditions.