为确定合理的区段小煤柱宽度,保证深部矿井沿空巷道的稳定性和实现工作面安全回采,以高家堡煤矿101工作面为例,采用钻孔应力监测方法,对101工作面推过前后的侧向煤体应力分布特征进行了实测研究,为沿空掘巷小煤柱留设提供实测资料.研究结果表明:工作面侧向煤体应力峰值至煤壁13～ 17 m,至煤壁9 m之内属于应力降低区,在该范围区内沿空掘巷,可避免受较高支承压力的影响,有利于巷道维护.在此基础上,采用数值模拟方法,优化分析得到103工作面沿空掘巷小煤柱合理宽度为6～7m,103回风巷(沿空掘巷)实际小煤柱宽度为7 m,通过对103沿空巷道围岩变形及锚杆锚固力现场监测,表明巷道围岩变形量不大,顶板、小煤柱帮及工作面帮巷道最大变形量分别为112、88、75 mm,锚杆锚固力变化相对较小,巷道维护状况较好,能够满足工作面安全回采.%In order to determine reasonable width of narrow coal pillar stability of roadway along goaf in deep mine and working face safe mining that determining the,taking No.101 working face of Gaojiabao Mine as the engineering background,the lateral coal stress distribution characteristics of No.101 working face was studied before and after mining by adopting the method of borehole stress measurement.Thus it provided a measurement basis for determining the width of narrow coal pillar of roadway driving along goaf.Results showed that the peak value location of lateral coal stress was within 13～ 17 m off the coal wall and the scope of stress decreasing zone was 9 m.Roadway driving along goaf within stress decreasing zone would avoid the influence of high abutment pressure and contribute to roadway maintenance.Based on the scope of stress decreasing zone measured,the optimized width of narrow segment pillar of roadway driving along goaf of No.103 working face was determined to be 6～7 m by using numerical simulation method.The actual width of narrow coal pillar of No.103 return airway (driving along goaf) was 7 m.According to surrounding rock deformation and the force condition of bolt monitoring of No.103 return airway,monitoring results confirmed that deformation of roadway changed slightly and the maximum deformation of roof and narrow coal pillar side and working face coal side were 112 mm,88 mm and 75 mm,and the force of bolt had relatively little change,roadway maintenance conditions was good and met safety mining of working face.
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