摘要
合理沿空掘巷时机可有效缓解采掘接续压力、减小巷道变形。采用理论分析方法,建立考虑矸石压缩效应的沿空掘巷覆岩结构力学模型,分析"煤壁(柱)-矸石"承载体系对覆岩稳定的协同控制效应。关键块触矸后下位岩层反向力矩无法协调其稳定时,关键块持续回转下沉产生对矸石的压缩,矸石承载力、下位岩层支撑力和岩块间水平推力随矸石压缩量增加近似呈负指数关系递增,共同协调关键块稳定,据此提出掘巷时机计算方法。在基本顶断裂线内掘巷会对覆岩结构稳定产生扰动,掘巷产生的关键块附加力矩将由矸石持续压缩恢复的应力协调承担,掘巷扰动时间、顶板下沉量与煤柱宽度负相关,适当增加煤柱宽度有利于缩短掘巷扰动时间,减小顶板下沉。研究成果对确定沿空掘巷时机和设计煤柱宽度具有借鉴意义。
Reasonable gob-side entry driving time can effectively relieve the continuity pressure and reduce entry deformation during mining-entry. In this paper, the overburden rock structure mechanical model in gob-side entry driving considering the effect of gangue compression has been established through theoretical analysis, and the synergistic control effect of "pillar-gangue" bearing system on the overburden structure stability has been analyzed. Research results have shown that when the reverse moment of hypogynous rock stratum cannot coordinate stability of the key block after it contacts the gangue, the continuous rotary subsidence of the key block will cause the compression on the gangue. Meanwhile, with the increase of the gangue compression value, the bearing capacity of gangue, the supporting force of hypogynous rock stratum, and the horizontal thrust between rock blocks increase approximately with negative exponential relation so as to coordinate the stability of the key blocks. Based on this, the determination method of the gob-side entry driving time has been put forward. Within the basic roof fracture line, entry driving will disturb the stability of overburden structure, and the additional moment of key blocks stress caused by driving will be assumed by continuous gangue compression recovery. The time of entry driving disturbance and roof subsidence value are negatively correlated with the pillar width, so an appropriate increase of pillar width is conducive to shortening the time of driving disturbance and reducing roof subsidence value. The research results can be used as a reference to determine the gob-side entry driving time and design the pillar width.
作者
王猛
夏恩乐
神文龙
刘小星
郑冬杰
刘鑫
WANG Meng;XIA Enle;SHEN Wenlong;LIU Xiaoxing;ZHENG Dongjie;LIU Xin(School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454000,China;Collaborative Innovation Center of Coal Work Safety,Henan Province,Jiaozuo,Henan 454000,China;School of Materials Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454000,China;Qipanjing Coal Mine,Shenhua Mengxi Coal Chemical Co Ltd,Wuhai,Inner Mongolia 016100,China)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2020年第5期928-935,共8页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(51704098,51804099)
河南省科技攻关计划项目(172102310363)
河南省教育厅科学技术研究重点项目(16A440004)。
关键词
沿空掘巷
矸石压缩
覆岩稳定
掘巷时机
煤柱宽度
gob-side entry driving
gangue compression
overburden structure stability
entry driving time
coal pillar width
