大倾角煤层群下行开采底板破坏机理及工程应用

Floor Failure Mechanism and Engineering Application of Downward Mining of the Large Dip Angle Coal Seam Group

为保证本煤层正常回采以及下部近距离煤层安全开采,须对采动底板破坏机制进行深入研究。以淮南某矿大倾角大埋深厚煤层开采为背景,建立了底板破坏力学模型,分别从沿走向和沿倾向的理论公式得出各自底板最大破坏深度,再比对结果确定整个工作面底板的最大破坏深度以及最大破坏深度出现的位置。通过在底板不同层位铺设测线,得到回采时垂直应力和剪切应力的分布情况及峰值大小曲线。将所得曲线进行对比分析,揭示了底板破坏过程应力分布规律以及峰值出现部位。其研究结果对于大倾角近距离煤层群的安全回采以及大倾角大埋深厚煤层底板承压水采煤工作面制定防治水措施具有指导意义和参考价值。

Further research should be done about the floor failure mechanism of mining in order to guarantee the normal mining of coal seam and the safe mining of lower coal seams in close distance. The floor damage mechanical model is established under the background of a mine in Huainan of thick coal seam mining with big angle and buried depth. The maximum damage depths are got respectively from theoretical formula along the strike and along the tendency. The maximum floor damage depth and the position of the maximum damage depth of the working face are determined by comparing the test results. The distribution and peak value curves of vertical stress and shear stress of mining are got by laying measuring line in different horizons of floor. The stress distribution law of floor damage process and area of peak value are revealed through the comparison and analysis of the curves. The research results have a guiding significance and reference value for safety mining in close distance to coal seam group of large dip and for the measures of water prevention in thick coal seam working face of big angle and buried depth with confined water in the floor.