高河矿双侧采动大巷变形破坏分析及合理煤柱尺寸留设研究

针对高河矿2#煤层大巷受双侧工作面采动影响导致巷道围岩大变形的问题,采用现场监测、数值模拟的方法,研究了大巷在双侧采动条件下的变形破坏特征及应力分布规律,并结合围岩变形量理论及锚杆锚索应用性验证确定出合理停采线位置。结果表明:双侧采动后北胶巷围岩最大破坏深度可达4m、顶底板移近量在0.5m以上,北轨巷距离采空区远,采动影响小,变形破坏小;单侧采动时停采线前方45m后主应力趋于稳定,双侧采动时停采线前方56m后主应力趋于稳定,且对称分布;双侧采动时距停采线60m以内的围岩塑性区面积大且呈非对称性,距停采线70m以上时塑性区较小且形态规则。结合围岩变形量理论及锚杆索应用性验证确定合理停采线位置为70m,应用于下区段的2309工作面和2304工作面,结果显示巷道变形得到明显控制,效果良好。

Deformation failure analysis and reasonable coal pillar size of two side mining roadway at gaohe mine

Aiming at the problem of large deformation of surrounding rock of No.2 coal roadway in gaohe coal mine , which caused by mining on both sides, field monitoring and numerical simulation methods are used to study the deformation and failure characteristics and stress distribution characteristics of the roadway under the condition of bilateral mining , and the reasonable stop-production line position is determined after theoretical analysis of surrounding rock deformation,. The results show: The maximum depth of damage of surrounding rock after double-sided mining can reach 4m, the approach distance of the roadway can reach more than 0.5m, and The north side of the track roadway is far from the goaf, so the mining influence and deformation damage are smaller; After one-side mining, the main stress tends to be stable after 45m in front of the stop line, when the two sides are driven, the principal stress tends to be stable after 56m in front of the stop line; The plastic zone of surrounding rocks within 60m of stop-mining line during mining on both sides is large and asymmetrical and the plastic zone is small and the shape is regular when 70m above the stop-line. Combined with theoretical analysis, the reasonable coal pillar size was determined to be 70m and applied to the 2309 and 2304 working faces in the following section. The roadway deformation is obviously controlled.