论文部分内容阅读
抽采煤层瓦斯是解决煤矿井下瓦斯超限难题的根本措施。但受煤层回采的影响,当回采工作面推过地面瓦斯抽采钻井位置后钻井套管迅速发生破坏,无法充分发挥其抽采采空区瓦斯的效应。因此,基于采场上覆岩层层面剪切滑移效应建立了地面钻井剪切变形破坏模型,并对套管随回采工作面推进在采场倾向方向上的位移变化规律进行了研究,指出:钻井剪切滑移与岩层厚度关系密切,为了减少剪切滑移破坏,地面抽采钻井的合理布孔位置宜为采场中部。同时,运用3DEC对模型进行了模拟分析,并与现场工程实例进行了对比验证。结果证明,模型描述的规律是可靠的,地面钻井布井宜选择靠近采场中部的位置。
Gas extraction from coal seam is the fundamental measure to solve the problem of methane overrun in coal mine. However, due to the influence of coal seam mining, when the working face pushes over the ground gas pumping and drilling position, the casing of the well dries rapidly and can not fully exert the effect of gas in the gob. Therefore, the shear deformation and failure model of ground drilling is established based on the shear-slip effect at the stratum overlying stratum, and the displacement variation rule of casing along the dip direction of mining face is studied. It is pointed out that the drilling The shear slip is closely related to the thickness of the rock formation. In order to reduce the shear slip damage, the reasonable hole location of the surface drainage drilling should be the middle of stope. At the same time, the model was simulated by 3DEC and compared with the field engineering examples. The result proves that the rule of model description is reliable, and the well drilling in the ground should be chosen to be close to the middle of stope.