大空间孤岛采场覆岩结构演化与区段煤柱合理宽度研究  

Evolution of overburden structure and reasonable width of section coal pillar in large space isolated island stope

作　　者：涂敏[1] 林远东 张向阳[1] 卜庆为 党家鑫 赵高明 TU Min;LIN Yuandong;ZHANG Xiangyang;PU Qingwei;DANG Jiaxin;ZHAO Gaoming(Co-Construction Key Laboratory of Safe and Efficient Coal Mining of Ministry of Education,Anhui University of Science and Technology,Huainan,Anhui 232001,China;School of Mechanics and Photoelectric Physics,Anhui University of Science and Technology,Huainan,Anhui 232001,China)

机构地区：[1]安徽理工大学煤矿安全高效开采省部共建教育部重点实验室,安徽淮南232001 [2]安徽理工大学力学与光电物理学院,安徽淮南232001

出　　处：《采矿与安全工程学报》2021年第5期857-865,共9页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金项目(52074007,52074008);安徽高校协同创新项目(GXXT-2020-056)。

摘　　要：大空间孤岛采场覆岩结构演化与稳定对区段煤柱的稳定性至关重要,而区段煤柱的稳定性与煤柱宽度有直接关联。为了提高区段煤柱稳定性和煤炭回收率,应用数理推导的方式研究大空间孤岛采场覆岩结构演化与区段煤柱的变形和承载特性,基于区段煤柱的极限平衡导出煤柱的合理宽度,确定影响区段煤柱合理宽度的系统内部参量;采用单因素分析法和函数增减性判别准则研究系统内部参量对区段煤柱合理宽度的影响规律,并由此提出减小煤柱宽度以提高回采率的措施。结果表明:大空间孤岛采场区段煤柱的合理宽度由煤层埋深、煤柱高度、工作面长度、煤柱上方悬臂岩梁长度、煤层到关键层高度、应力集中程度、关键层悬顶距、煤柱内部弹塑性区交界面的侧压系数及煤岩体交界面的摩擦系数等9个系统内部参量共同确定;区段煤柱的合理宽度随着煤层埋深、煤柱高度、工作面长度、煤柱上方悬臂岩梁长度、煤层到关键层高度、应力集中程度和煤柱内部弹塑性区交界面处侧压系数的增大而增大,随着关键层悬顶距和煤岩体交界面上摩擦系数的增大而减小。基于系统内部参量对区段煤柱合理宽度的影响规律,提出控制大空间孤岛采场工作面长度、爆破或水力切顶以改变覆岩结构、煤柱高强注浆和锚喷支护及提高煤岩体摩擦系数等措施减小大空间孤岛采场区段煤柱宽度以达到提高回采率的目的。The evolution and stability of overburden structure in large space isolated island stope are very important to the stability of section coal pillar which is directly related to the width of coal pillar.To improve the stability of section coal pillar and coal recovery rate,the evolution of overburden structure and deformation and load-bearing characteristics of section coal pillar in large space isolated island stope were studied through mathematical derivation.Based on the limit equilibrium of section coal pillar,reasonable width of section coal pillar was derived,and the internal parameters of the system affecting the width were determined.The influence law of internal parameters on the reasonable width of section coal pillar was studied through single factor analysis method and the criterion of function increase and decrease,and measures to reduce the width of section coal pillar to improve recovery rate were proposed based on the analysis.The results have shown that the reasonable width of coal pillar in large space isolated island stope is jointly determined by 9 internal system parameters:the burial depth of coal seam,the height of coal pillar,the length of working face,the length of cantilever beam above section coal pillar,the height of coal seam to key stratum,the degree of stress concentration,the suspension roof distance of key stratum,the coefficient of lateral pressure at the interface of elastic-plastic interface inside section coal pillar and the coefficient of friction at the interface between coal and rock mass.The reasonable width of section coal pillar increases with the increase of the former seven parameters and decreases with the increase of suspension distance of key stratum and the friction coefficient at the interface between coal and rock mass.Based on the influence of the system internal parameters on the reasonable width of section coal pillar,measures are proposed to reduce the width of section coal pillar in large space isolated island stope and improve the recovery rate by controllin

关 键 词：大空间孤岛采场 特厚煤层综放 覆岩结构演化 区段煤柱稳定性 

分 类 号：TD803[矿业工程—矿山开采]