论文部分内容阅读
针对晋华宫矿多煤层下行开采过程中层间赋存有19m厚中粒砂岩的特殊条件,在分析其覆岩结构特征的基础上建立了多煤层开采的围岩整体结构模型,据此提出了“层间等效基本顶”的概念,通过理论分析探讨了层间等效基本顶覆岩载荷和等效厚度.结果表明:从砌体梁结构稳定角度认为咬合处即为等效基本顶分界,即厚基本顶中下部未损伤区域作为砌体梁结构的主承载区域,其厚度为基本顶等效厚度.等效基本顶破断步距为19.1m,与现场矿压监测结果一致,较好地解释了11号煤层开采时19m厚中粒砂岩作为基本顶时周期来压步距变小的原因.
Aiming at the special conditions of 19m thick medium sandstones deposited between layers in the downward movement of multiple coal beds in Jinhuagong Mine, the whole structure model of surrounding rock for multiple coal seam mining was established based on the analysis of the structural characteristics of overburden rock. The concept of “equivalent basic roof between layers” is discussed, and the theoretical equivalent load and equivalent thickness of the equivalent top overburden rock are discussed. The results show that the occlusal position is equivalent to the stability of the masonry structure The basic top demarcation, that is, the unbreakable area in the middle, lower part of the thick basic roof, is the main bearing area of the masonry beam structure, and the thickness is the basic top equivalent thickness.The equivalent basic roof rupture step is 19.1m, which is consistent with the monitoring results , Which explains why the pressure step spacing is smaller when the 19-m-thick medium-grain sandstone is used as the basic roof when No. 11 coal seam is mined.