A belt heading in a Huainan coalmine has a depth of about 730m, and rock mass ruptured zone encountered during its driving. Since large thickness and plenty of water have caused serious deformation of the heading and cannot be run-through. Based on mine area geological condition analysis, surface advance grouting technique has used to consolidate crumbling rocks. Directional branching drilling technology is used to reduce drilling site land requisition and engineering workload; "freely falling casing"technology to consolidate whipstocking sector wall; based on spacing between slurry crossed over boreholes and slurry leakage points to determine slurry spreading range; based on leakage quantity and roadway deformation observed results to determine grouting coverage of influence, thus to adjust grouting parameters and grouting completion criterion. Finally put forward suggestions to strengthen underground roadway monitoring during surface grouting.%淮南某矿井胶带机巷离地表深度约730m,在掘进中遇到岩体破碎带.由于破碎带厚度大,且富含水,造成了巷道变形严重,无法贯通.在分析矿区地质条件的基础上,实施了地面预注浆技术来加固破碎岩体:采用定向分支孔钻进技术以减小钻场征地面积和节约钻进工程量;运用飞管技术加固造斜段钻孔孔壁;根据窜浆钻孔的孔间距及井下漏浆点位置,确定浆液扩散半径;根据漏浆量及巷道变形观测结果确定注浆对巷道影响区的范围,并依此调整注浆参数和注浆结束标准.最后提出了地面注浆期间须加强井下巷道监测的建议.
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