采空区下特厚煤层工作面顶板支护强度的确定

Determination of Roof Support Strength at the Working Face in Extra-Thick Coal Seam Under Goaf

针对控顶区顶板下沉量过大导致压架事故的问题,以山西临县华烨煤矿采空区下特厚煤层大采高综放开采为工程背景,采用3DEC离散元数值模拟软件,对不同支护强度下采空区下方特厚煤层工作面控顶区顶板的来压规律进行模拟分析,对工作面液压支架应给与顶板的支护强度进行了研究。研究结果表明:工作面来压强度呈现高—低—高—低的阶段性变化;控顶区顶板下沉量随支护强度增加呈指数关系下降;实例工作面顶板最大下沉量的安全值为45cm,相应的支护强度应为1.52MPa。研究结果对类似条件下液压支架的选型具有一定的理论指导意义。

Aiming at the problem of frame pressing accident caused by excessive roof subsidence in the roof control area, the fully mechanized caving with large mining height in extra-thick coal seam under the goaf of Huaye coal mine in Linxian County, Shanxi Province was taken as the engineering background. 3 DEC discrete element numerical simulation software was used to analyze the pressure regularity of the roof in the roof control area at the working face in extra-thick coal seam under goaf with different support strength. The support strength of the hydraulic support to the roof of the working face was studied. The results show that the pressure strength of the working face changes from high to low to high to low, and the roof subsidence in the roof control area decreases exponentially with the increase of support strength. The safety value of the maximum roof subsidence of the working face is 45 cm, and the corresponding support strength should be 1.52 MPa. The research results provide a certain theoretical guiding significance for the selection of hydraulic support under similar conditions.