上山保护煤柱应力传递规律解析

Analysis of stress transfer law of coal barrier pillar of roadway

为研究煤层下行开采过程中上山保护煤柱应力传递规律,防治深部开采中煤柱支承压力向下传递形成应力集中引起的动力灾害,采用理论分析和数值模拟方法,基于弹性力学原理推导上山保护煤柱应力传递规律函数,并应用于某矿煤柱应力传递;运用FLAC3D数值模拟某矿1#煤层遗留煤柱对2#煤层巷道掘进的影响.研究结果表明:上山保护煤柱力学模型包括大煤柱和小煤柱2个部分,煤柱垂直应力传递具有扩散和衰减作用;2#煤层处于煤柱下方时,煤体应力为19.93~22.39 MPa,垂直应力增量峰值为3.13 MPa,高出原岩应力13.6%,增大了动力灾害发生的危险;煤柱对2#煤层影响范围为进煤柱前100m到出煤柱后100m.研究结论揭示了上山保护煤柱垂直应力传递规律,有助于防治由煤柱支承压力集中引起的动力灾害.

To study the law of stress transfer of coal barrier pillar of roadway and prevent the dynamic disaster caused by stress concentration in deep mining,the stress transfer law is studied by using theoretical analysis and numerical simulation.Based on the elastic mechanics,this paper deduces the stress transfer rule function of coal barrier pillar of roadway and applies it to the stress transfer of a coal pillar in a certain mine.FLAC3D is used to simulate the influence of the left coal pillar of 1#coal seam on the tunneling of 2#coal seam.The research shows that the mechanical model of coal barrier pillar of roadway includes the big and the small coal pillar mechanical model,and the vertical stress transfer of the coal pillar has the function of diffusion and attenuation;when the coal seam is below the coal pillar,the stress of the coal body is 19.93~22.39 MPa,and the peak value of the vertical stress increment is 3.13 MPa,which is 13.6%higher than that of the original rock stress.The increasing of coal stress increases the risk of dynamic disaster;the influence range of the coal pillar to the 2#coal seam is from 100 m before the coal pillar to 100 m after the coal pillar.The research results reveal the vertical stress transfer law of the protective coal pillar,which is helpful to prevent the dynamic disaster caused by the abutment pressure concentration of the coal pillar.