摘要
为研究充填采场覆岩变形特征,基于充填采场围岩变形的时空效应,将充前移近量、欠接顶量与充填体压缩量作为覆岩变形的主要来源,揭示了覆岩移动的“三量关系”,并分析了三量变形的影响因素。基于压力平衡拱理论,建立围岩压力与充填体承载力的平衡关系,研究“三量关系”的协同作用,并提出覆岩变形控制的“三度原则”,通过控制充填速度、充填密实度和充填体强度等措施降低覆岩变形。研究结果表明,充前移近量与空顶时间及充填步距呈正比,其变形在回采一阶段显著低于末阶段,同时,充填效率降低,导致空顶时间增加,其变形随之增加;欠接顶量随泌水率增大而增大,其欠接顶区域呈三角形分布,随煤层倾角增大,欠接顶范围减小,而欠接顶高度在充填支巷上口增大;充填体压缩量与其弹性刚度呈反比。提高充填速度及密实度在充填前期显著降低覆岩变形,而提高充填体强度在充填后期是控制覆岩变形的关键因素。数值模拟结果表明,在两阶段回采模式中,充填体在一阶段时仅产生部分接顶,在二阶段时产生完全接顶区和间断接顶区,最终形成完全接顶。基于覆岩变形控制的“三度原则”,昊源煤矿采用连采连充式胶结充填采煤技术,实现了连续采煤与连续充填的平行作业,显著提高了充填效率,降低了覆岩的充前变形。结果表明,上覆岩层仅产生较小的离层,极大地维持了围岩完整性,实现了对上覆岩层的变形控制,验证了“三度原则”对变形控制的有效性,为类似条件下的覆岩变形控制研究提供了借鉴。
In order to study the characteristics of overburden deformation in the filled goaf,based on the spatial and time effects of the deformation of the surrounding rock in the filled goaf,the pre-filling displacement,the under-connection and the compression of the filling body are taken as the main sources of the overburden deformation.The“three-measurement relationship”of the overburden movement is revealed,and the influencing factors of the three-measurement deformation are analyzed.Based on the pressure balance arch theory,the equilibrium relationship between the pressure of surrounding rock and the bearing capacity of filling body is established,and the synergistic effect of“three measurement relationship”is studied,and the“three degree principle”of overburden deformation control is proposed.The overburden deformation is reduced by controlling the filling velocity,filling compactness and filling intensity.The research results show that the pre-filling displacement is proportional to the overhanging roof time and the filling step,and its deformation is significantly smaller in the first stage of recovery than in the last stage,and the filling efficiency decreases,leading to an increase in the overhanging roof time and its deformation increases.The under-connection amount increases with the increase of bleeding rate,and its under-connection area is triangularly distributed,and the under-connection range decreases with the increase of coal seam inclination,while the under-connection height increases at the upper entrance of the filling branch lane.The compression of the filling body is inversely proportional to its elastic stiffness.Increasing the filling speed and compaction significantly reduces the overburden deformation in the early stage of filling,while increasing the filling body strength is the key factor to control the overburden deformation in the late stage of filling.The numerical simulation results show that in the two-stage mining mode,the filling body produces only partial roof contact in t
作者
徐斌
杨仁树
李永亮
路彬
骆浩浩
李成孝
XU Bin;YANG Renshu;LI Yongliang;LU Bin;LUO Haohao;LI Chengxiao(School of Mechanics and Architecture Engineering,China University of Mining and Technology-Beijing,Beijing100083,China;School of Energy and Mining Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2022年第S01期49-60,共12页
Journal of China Coal Society
基金
国家自然科学基金资助项目(51804310)
关键词
胶结充填
三量关系
三度原则
压力平衡拱
连采连充
cement filling
three-quantity relationship
three-degree principle
pressure balance arch
continuous mining and continuous backfilling
