Study on supporting technology of narrow coal pillar driving along gob in medium-thick coal seam
WANG Junfeng
为了减少综采工作面沿空掘巷煤柱的煤炭损失量并保证支护效果,以南梁煤矿3-1煤层30100工作面辅助运输巷为研究背景,采用理论分析、数值模拟及现场实测的综合研究方法,对南梁煤矿综采工作面煤柱的最小宽度及其支护方案进行了研究。
研究表明:在巷道埋深为100 m、采高为2 m、窄煤柱采空区侧巷道煤帮的支护强度为0.25 MPa时,窄煤柱采空区侧基本顶断裂线位置深入煤壁2.53 m,这也是采空区影响窄煤柱稳定的塑性区宽度;在采空区影响窄煤柱的塑性区宽度为2.53 m、窄煤柱帮锚杆的有效长度为1.5 m、巷道埋深为100 m时,根据极限平衡理论确定出南梁煤矿3-1煤层30100工作面窄煤柱宽度为5 m;针对宽5 m的窄煤柱,确定巷道支护方案为窄煤柱侧锚杆支护、顶板锚杆与锚索联合支护、实体煤侧不支护的支护方案及其合理支护参数,窄煤柱侧的巷帮锚杆为16 mm×2 000 mm、间排距900 mm×1 000 mm、锚固长度600 mm,每排布置3根锚杆;巷道顶部采用20 mm×2 200 mm型左旋螺纹钢锚杆(间排距1 000 mm×900 mm,每排5根)与15.24 mm×6 000 mm型锚索(排距为2.0 m)联合支护。现场实测表明,该方案能够满足巷道掘进和工作面回采的安全要求,值得在条件类似的矿井中推广。
In order to reduce the amount of coal loss in fully mechanized mining face and ensure the supporting effect, the width of coal pillar and support scheme of the auxiliary transportation lane in the No.30100 face of the 3-1 coal seam of Nanliang Coal Mine was taken as the research background, using theoretical analysis, numerical simulation and field measurement,the minimum width and supporting scheme of coal pillars in fully mechanized coal mining face of Nanliang Coal Mine are studied.The study shows that when the depth of roadway is 100 m, the mining height of coal seam is 2 m, and the support resistance of roadway coal rib in gob of the narrow coal pillar is 0.25 MPa, the distance between the location of the basic roof fracture line at the gob side of narrow coal pillar and the coal wall at the gob side is 2.53 m, which is also the width of the plastic zone in which the gob affects the stability of the narrow coal pillar; when the width of the plastic zone affecting the narrow coal pillar in the gob is 2.53 m, the effective length of the anchor in the narrow coal pillar is 1.5 m, and the depth of roadway is 100 m, the width of narrow coal pillar in the No.30100 working face of No.3-1 coal seam in Nanliang coal mine is determined to be 5 m according to the limit equilibrium theory; for narrow coal pillars with a width of 5 m, it is determined that the support scheme of roadway is bolt support at the side of narrow coal pillar, combined with support of roof bolts and anchor cables. The bolts on the side of the narrow coal pillars are ø16 mm×2 000 mm, the spacing between rows is 900 mm×1 000 mm, the anchoring length is 600 mm, and 3 bolts are arranged in each row; the top of the roadway is ø20 mm×2 200 mm type left-handed threaded steel bolts (the spacing between rows is 1 000 mm×900 mm, 5 in each row), combined with ø15.24 mm×6 000 mm anchor cable (row distance is 2.0 m). Field measurement shows that the width of narrow coal pillar and support scheme can meet the safety requirements of roadway tunneling and mining of working face in Nanliang coal mine, and it has great economic benefits, which is worthy to be popularized in mines with similar conditions.
medium-thick coal seam;gob-side entry driving; narrow pillar width;bolt support;cable support
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会