摘要
为了提高特厚煤层资源回收率并改善临空巷道应力环境,以铁北煤矿主采Ⅱ_(2a)特厚煤层为工程背景,利用巷道顶板断裂后形成"内外应力场"理论和煤柱极限平衡区理论,确定了临空巷道窄煤柱留设宽度范围为5.6~10.84 m。二次回采扰动影响下的宽煤柱侧向支承压力分布特征显示,煤柱0~7.5 m内煤体处于塑性状态,最终确定沿空掘巷窄煤柱合理留设尺寸为8.0 m。现场工程实践表明,掘巷后煤柱3.0 m范围以外裂隙基本不发育,煤体完整性较好;锚杆受力变化波动不大;掘巷32 d后巷道变形量逐渐趋于稳定,围岩变形控制效果良好。
In order to increase the recovery rate of extra-thick coal seam and improve the mechanical environment of the roadway,the width of narrow coal pillar along gob-side entry is determined to be 5.6 to 10.84 m,based on the main mining Ⅱ_(2a) thick coal seam in Tiebei mine,on the formation of the"internal and external stress field"theory after the roof fracture,combined with coal pillar limit equilibrium zone theory.According to distribution characteristics of lateral support pressure of wide coal pillar under the influence of secondary mining disturbance,the coal body within the range of 0 to 7.5 m is in a plastic state.The reasonable width of narrow coal pillar along gob-side entry is determined to be 8.0 m.On-site engineering practice shows that fissure of coal pillar within the range of 3.0 m is basically not developed,and the coal body integrity is good.The bolt force fluctuations are not large.Roadway deformation tends to be stable gradually after 32 days of tunnel excavation.The effect of surrounding rock control is good.
作者
高晓进
张洪清
张震
李寿君
海永夫
GAO Xiaojin;ZHANG Hongqing;ZHANG Zhen;LI Shoujun;HAI Yongfu(GCTEG Coal Mining Research Institute,Beijing 100013,China;Coal Mining&Design Branch,China Coal Research Institute,Beijing 100013,China;Coal Mining&Designing Department,Tiandi Science&Technology Co.,Ltd.,Beijing 100013,China;Jalai Nur Coal Industry Co.,Ltd.,Manzhouli 021410,China)
出处
《煤炭技术》
CAS
北大核心
2022年第1期36-40,共5页
Coal Technology
基金
天地科技股份有限公司科技创新创业资金专项项目(2020-TD-ZD016,2019-TD-QN006)
华能集团总部科技项目(HNKJ17-H27)。
关键词
沿空掘巷
窄煤柱
侧向支承压力
围岩控制
gob-side entry driving
small pillar
lateral abutment pressure distribution
surrounding rock
