断层影响下不同顶板岩体组合结构对底板采动效应的影响研究

Influence of Roof Rock Mass Structure on Mining Effect of Floor with Fault under Mining Condition

摘要: 为探究下伏底板岩层受正断层切割情况下，上覆顶板岩体结构对底板采动效应的影响，本文根据煤层顶底板地质构造特征和岩性结构特点，运用FLAC3D分别建立硬–软–硬、软–硬–软、均质硬岩和均质软岩四种顶板结构的数值模型，模拟分析了不同顶板结构对含断层底板变形破坏特征的影响。研究结果分析表明：在断层影响下，均质软岩顶板组合的底板采动应力、位移和破坏深度相对较大，破坏程度最大；均质硬岩顶板组合的底板采动应力、位移和破坏深度相对较小，破坏程度最小；而硬–软–硬和软–硬–软顶板组合的底板应力、位移、破坏深度以及底板的破坏程度位于前两者之间。

Abstract: In order to explore the influence of the overlying roof rock mass structure on the floor mining effect under the condition that the underlying floor strata are cut by normal faults, based on the ge-ological structure characteristics and lithologic structure characteristics of the roof and floor of the coal seam, the numerical models of four roof structures of hard-soft-hard, soft-hard-soft, ho-mogeneous hard rock and homogeneous soft rock are established by FLAC3D, and the effects of different roof structures on the deformation and failure characteristics of the fault floor are simu-lated and analyzed. The analysis shows that, under the influence of the fault, the mining stress, displacement and failure depth of the base plate of the homogeneous soft rock roof combination are relatively large, and the failure degree is the greatest. The mining stress, displacement and failure depth of the base plate of the homogeneous hard rock roof are relatively small, and the failure degree is the smallest, while hard-soft-hard and soft-hard-soft roof combination is combined. The stress, displacement, failure depth and failure degree of the floor are located between the former two.