沿空巷道二次采动顶板结构演化特征研究

Study on Roof Structure Evolution Characteristics of Secondary Mining in Roadway along Goaf

采用理论分析、数值模拟的方法对二次采动过程中沿空巷道的围岩演化过程进行研究。结果表明:二次采动时,本工作面采动压导致超前段基本顶上的载荷进一步增加,导致煤柱所承受的压力增加,煤柱及巷道围岩力学环境恶化变形破坏严重;巷道两侧垂直应力分布呈现不同的偏向性,一次采动时煤柱仍保持一定的承载能力,巷道煤柱侧垂直应力分布大于回采侧,二次采动时煤柱变形破坏严重,使得巷道回采侧垂直应力分布大于煤柱侧,非对称性明显。

The evolution process of surrounding rock in roadway along goaf in the process of secondary mining is studied by means of theoretical analysis and numerical simulation.The results show that during the secondary mining,the mining pressure of the working face leads to the further increase of the load on the basic roof above the front section,the increase of the pressure borne by the coal pillar,the deterioration of the mechanical environment of the coal pillar and the surrounding rock of the roadway,and the serious deformation and damage;the vertical stress distribution on both sides of the roadway presents different biases.During the primary mining,the coal pillar still maintains a certain bearing capacity.The vertical stress distribution on the coal pillar side of the roadway is greater than that on the mining side.During the secondary mining,the coal pillar deformation and damage is serious,so that the vertical stress distribution on the mining side of the roadway is greater than that on the coal pillar side,and the asymmetry is obvious.