School of Safety Engineering, China University of Mining and Technology

双系煤层条件下的重复开采使得单层开采后已经趋于稳定的岩层再次“活化”,加剧了变形破坏的影响。因此,对煤层重复开采后引起的覆岩移动规律进行研究具有十分重要的意义。基于“力学模型+几何方法”融合的IFM-KS模型,提出了适用于多层开采条件下的岩层移动计算模型,揭示了煤层重复开采情况下岩层二次扰动后的移动变形规律。通过理论计算及UDEC数值计算方法验证了双系煤层开采情况岩层移动新模型的预测准确性。结果表明,理论计算的岩层位移结果与采用数值模拟得到的结果整体呈相同的沉降趋势,平均误差率约为15%。结合岩层移动模型计算结果,层间及上覆岩层空隙率的相关计算,与单层煤开采相比,双系煤层开采后造成的采空区空隙率变化剧烈,岩层破坏更加严重,上下采空区可通过裂隙沟通形成漏风通道。该计算模型能为类似采动件下岩层变形预计、采空区空隙率分布等提供一定的参考。

Repeated mining of dual coal seams will reactivate the stable rock layers caused by mining of a single coal seam, exacerbating the impact of deformation and damage. Therefore, it is of great significance to study the laws of overlying rock strata movement caused by repeated mining of coal seams. Based on the influence function method-key stratum (IFM-KS) model, a rock strata movement calculation model suitable for multi-layer mining conditions was proposed, revealing the movement and deformation laws of rock strata after secondary disturbance due to repeated coal seam mining. The accuracy of the new model for predicting rock movement in dual coal seam mining was verified by theoretical calculation and numerical simulation with UDEC. The results of theoreti-cal calculation of rock displacement had the same trend as those of numerical simulation, with an average error rate of about 15%. Based on the calculation results of the rock movement model and the porosity of the interlayer and overlying strata, compared with single-layer coal mining, the porosity of the goaf caused by the mining of dual coal seams changes sharply, and the rock damage tends to be more severe. The upper and lower goaf can beconnected through cracks forming air leakage channels. This calculation model can provide certain guidance for prediction of rock deformation and analysis for the distribution of porosity in goaf areas under similar mining conditions.

1 单层煤开采上覆岩层移动模型
2 双系煤开采上覆岩层移动模型
2.1 双系煤层开采岩层移动模型建立
2.2 模型沉降参数
3 案例
3.1 数值模拟研究方案
3.1.1 模型和参数设置
3.1.2 模型边界条件设置
3.1.3 模拟开挖方案
3.2 模型计算及其结果对比
3.3 双系煤层开采对覆岩空隙率的影响
3.4 物理模型结果对比
4 结论

程健维, 盛树平, 冉德志, 等. 基于IFM-KS模型的多层煤开采上覆岩层移动模型[J]. 采矿与岩层控制工程学报, 2024, 6(1): 013021.

CHENG Jianwei, SHENG Shuping, RAN Dezhi, et al. Research on overburden rock movement model based on IFM-KS model for multi-seam coal remining[J]. Journal of Mining and Strata Control Engineering, 2024, 6(1): 013021.