深部沿空掘巷窄煤柱宽度留设及围岩控制技术研究

Study on narrow coal pillar width setting and surrounding rock control of gob-side roadway excavation in deep coal mine

以邢东矿11214运输巷为背景,应用内外应力场及极限平衡理论、工程实践的方法,确定深部沿空掘巷窄煤柱合理宽度,并针对性地提出了“巷帮全螺纹锚杆支护+顶板螺纹钢超强锚杆支护+冷拔丝金属网配合菱形金属网双网护巷+钢绞线锚索补强支护”的围岩控制技术。理论计算显示窄煤柱合理宽度范围为6.47~9.77 m,最终确定为8 m。工程实践表明,8 m宽度窄煤柱及围岩控制技术可有效控制沿空巷道围岩变形,巷道掘出35 d后巷道收敛变形趋于稳定,稳定时顶底板、煤柱帮以及实体煤帮最大变形量分别为67、57、64、62 mm,变形处于合理范围内,巷道岩体的控制效果良好,能够达到安全生产的要求。

No.11214 transport roadway of Xingdong Mine was taken as the background,the internal and external stress field theory,limit equilibrium zone theory,and engineering practice were applied to determined the reasonable width of narrow coal pillar in gob-side roadway excavation with great depth.The surrounding rock control technology of“full threaded bolt support of roadway sides+super strong bolt support for the roof+cold-drawn wire metal mesh with diamond-shaped metal mesh double network protection+steel strand anchor cable reinforcement support”was put forward.Theoretical calculations showed that the reasonable width range of narrow coal pillars was 6.47~9.77 m,which was finally determined to be 8 m.Engineering practice showed that 8 m width narrow coal pillar and surrounding rock control technology could effectively control the deformation of the gob-side entry driving,the roadway deformation tended to stabilize after 35 d of roadway excavation,the maximum deformation of top and bottom slab,coal pillar wall and solid coal wall,at stabilization were 67 mm,57 mm,64 mm and 62 mm respectively,the deformation was within a reasonable range,the rock around the roadway was well controlled and met the requirements of safe production.