采空区矸石压实过程对煤柱支承压力的影响

为了研究采空区压力及煤柱上支承压力随采空区矸石压实程度的变化规律,通过实验室试验、数值模拟等方法,探讨建立了采空区矸石压缩模量与矸石压实率之间的关系式,分析了采空区矸石压力分布随矸石压实率变化规律;基于弹性基础梁理论和弹塑性极限平衡理论建立了煤柱上支承压力与采空区矸石压力间的关系式,分析了煤柱支承压力峰值大小、峰值位置受矸石压实率影响规律。最后,将采空区矸石压缩模量与矸石压实率之间的关系用于FLAC3D数值模拟,与理论形成对比,证明二者结果基本一致。研究表明:矸石压实率越大,采空区压力回升越快,压力恢复至原岩应力的位置距煤壁越近,对应的煤柱上支承压力峰值位置越靠近煤壁,压力峰值越小。

Influence of Gangue Compaction Process on Coal Pillar Supporting Pressure in Goaf

To study the variation law of gob pressure and abutment pressure on coal pillar with the degree of compacting gangue in gob,by means of laboratory test and numerical simulation,the relationship between the compression modulus of gangue in goaf and the compaction rate of gangue was discussed,and the change law of the pressure distribution of gangue in goaf with the compaction rate of gangue was analyzed.Based on the elastic foundation beam theory and elastic-plastic limit equilibrium theory,the relation between the abutment pressure on the coal pillar and the gangue pressure in the goaf is established,and the influence law of the peak value of the abutment pressure on the coal pillar and the peak value position on the gangue compaction rate is analyzed.Finally,the relationship between the compression modulus of gangues in goaf and the compaction rate of gangues was applied to FLAC3 Dnumerical simulation,which was compared with the theory and proved that the two results were basically consistent.The results show that the higher the compaction rate of gangue,the faster the goaf pressure will recover,and the closer the pressure will be to the original rock stress,and the closer the peak position of supporting pressure on the corresponding coal pillar will be to the coal wall,and the smaller the pressure peak will be.