浅埋煤层综采工作面10 m区段小煤柱稳定性分析

Stability analysis of 10 m small coal pillar for fully mechanized mining face in shallow coal seam

留设煤柱保护采准巷道仍是我国许多煤矿采取的主要护巷方法,但同时也损失了大量的煤炭资源。通过理论分析、数值模拟和现场监测分析方法对大砭窑煤矿5-2号煤层浅埋综采10 m区段小煤柱稳定性进行了分析。采用极限平衡区理论对合理煤柱宽度进行了验证,得出预留煤柱宽度不应小于9.94 m;数值模拟表明,当煤柱宽度小于10 m时,顶板下沉量、两帮移近量增幅较为显著,当煤柱宽度大于10 m后,顶板下沉量、两帮移近量变化较为平缓。采用顶板离层仪对巷道变形量进行监测,验证了5-2号煤层综采区段煤柱留设10 m是可行的,研究结果为类似工况条件下区段煤柱宽度留设提供了理论依据。

Retaining coal pillar to protect the mining roadway is still the main roadway protection method adopted by many coal mines in China,but it also loses a lot of coal resources.Through theoretical analysis,numerical simulation and field monitoring analysis,the stability of 10 m small coal pillar for shallow fully mechanized mining face in No.5-2 coal seam of Dabianyao Coal Mine is analyzed.The calculation based on the limit equilibrium theory shows that the reserved coal pillar width should not be less than 9.94 m.The numerical simulation shows that when the coal pillar width is less than 10 m,the increase of roof subsidence and two-side displacement is more significant,while when the coal pillar width is greater than 10 m,the change of roof subsidence and two-side displacement is more gentle.The monitoring results of roadway deformation by roof separation instrument show that it is feasible to reserve 10 m coal pillar for fully mechanized mining face of No.5-2 coal seam,which provides a theoretical basis for determining the width of coal pillar under similar working conditions.