上行开采过程中，若下部煤层采用柱式开采，则在采动压力的影响下，可能造成 层间岩体及下部煤层采空区遗留煤柱的失稳，进而引起上覆岩层的垮落破坏和长壁工 作面底板岩层的失稳，威胁上部煤层采煤工作面的安全生产。因此，开展柱采区域上 方煤层上行开采可行性的研究非常必要。 报告以百子煤矿为研究对象，综合运用理论分析、物理模拟和数值模拟的方法， 对柱式开采的 8 号煤层上部 5 号煤层上行长壁开采的可行性进行了研究。理论分析将 采动压力作为分析上行开采可行性的关键参数，给出了采动压力的预计公式，得出 8 号煤层与 5 号煤层之间最小厚度 20m 层间岩体的最大破坏深度为 3.2m，层间岩体抗拉 强度和抗剪强度稳定性系数分别为 5.9 和 4.1，并基于有效面积理论得出下伏 8 号煤层 所留煤柱稳定性系数为 2.2，表明层间岩体与 8 号煤层所留煤柱保持稳定。物理模拟实 验研究表明，8号煤层柱式开采过程中承受的最大支承压力为 2.965Mpa；5 号煤层长壁 推进过程中，老顶初次来压步距在 58m 左右，周期来压平均步距 16.7m，来压过程中 的采动压力仅影响层间岩体的一定深度，层间岩体保持稳定；5 号煤层采空区域下方底 板岩层中形成明显的减压区域，且顶板来压时仅在切眼处保护煤柱与煤壁前方煤体下 方的传感器上出现应力集中现象，但监测到的煤柱支承压力值均小于 4MPa，远低于 8 号煤层煤柱的承载强度，表明 5 号煤层上行开采过程中 8 号煤层所留煤柱保持稳定； 数值模拟实验揭示了 5 号煤层长壁开采过程中 8 号煤层所留煤柱与层间岩体的应力分 布与演化规律，表明百子煤矿上行开采时层间岩体和下伏 8 号煤层煤柱均具有足够的 强度，不会发生失稳现象。 报告研究成果对于百子煤矿的上行开采具有指导意义，对于其它类似开采条件煤 矿的上行开采也具有良好的借鉴意义。 关 键 词，上行开采；层间岩体；支承压力；采动压力 研究类型，应用基础研究Subject : Feasibility study of upward mining at Baizi Coal mine Specialty : Mining Engineering Name : Wu Juntao (Signature) Instructor : Shao Xiaoping (Signature) Miao Yanping (Signature) ABSTRACT In the process of upward mining, if the lower coal seam is used in pillar mining, it was under the influence of pressure, the instability of the residual coal column in the interlayer and the lower coal seam is possible, will be cause the collapse of the overlying rock formation and the instability of the floor of the long wall face plate, To threaten the safety production of upper coal seam mining. Therefore, It is necessary to study the feasibility of mining on top of the coal seam. The paper studies the Baizi Coal mine, Methods of theoretical analysis, physical simulation and numerical simulation, The feasibility of the wall mining of the top coal seam #5 of coal seam #8 is studied in this paper. The theoretical analysis will take the pressure as the key parameter to analyze the feasibility of upward mining, the prediction formula for the pressure of mining is given, conclusion maximum damage depth is 3.2m between the coal seam #8 and the coal seam #5 smallest layer of 20m, the stability factor of the tensile strength and shear strength of the interlayer was 5.9 and 4.1, based on the theory of effective area obtain stability coefficient of the coal column in the coal seam of lower #8 is 2.2, It shows that interlayer rock body and coal pillar for the coal seam #8 hold steady. The study of physical simulation experiments shows that the maximum support pressure in the coal seam #8 is 2.965Mpa; In the process of the long wall of the coal seam #5, the old roof first came in about 58m, the average period is 16.7m, the compressive pressure in the process affects only the depth of the interlayer, the interlayered rock remains stable; a significant decompression zone is formed in the bottom layer of the subsurface of the coal seam #5 bed zone, the stress concentration of the coal column and the sensor on the lower part of the coal wall in front of the coal wall is only applied when the roof is pressed, but pressure value of the coal column supported by the monitoring is less than 4MPa, far lower than the load strength of the coal seam #8 pillar, indicates that the coal column of the coal seam #8 is stable In the process of coal seam #5 upward mining; The numerical simulation is revealed the stress distribution and evolution of coal column and interlayer rock in the coal seam #8 In the process of coal seam#5 length, It shows the Baizi Coal mine in upward mining interlayer rock body and the coal pillar of the lower volt #8 has sufficient strength, there will be no instability. The results of the paper are of guiding significance for upward mining of Baizi Coal mine, there is also good reference for the upward mining of other similar mining conditions coal mine. Key words: Upward mining;Interlayer rock body;Abutment pressure;Mining stress Thesis : Application Researc目录 I 目 录 1 绪论 ............................................................................................................................................................ 1 1.1 选题的背景和意义........................................................................................................... 1 1.2 上行开采国内外研究现状............................................................................................... 2 1.2.1 上行开采国外研究现状............................................................................................ 2 1.2.2 上行开采国内研究现状............................................................................................ 4 1.3 煤柱稳定性研究现状....................................................................................................... 7 1.3.1 煤柱强度理论............................................................................................................ 7 1.3.2 煤柱荷载理论.......................................................................................................... 10 1.4 研究内容及技术路线..................................................................................................... 12 1.4.1 研究内容.................................................................................................................. 12 1.4.2 技术路线.................................................................................................................. 12 2 百子煤矿开采地质条件分析 ............................................................................................................. 13 2.1 矿井概况......................................................................................................................... 13 2.2 井田地质......................................................................................................................... 13 2.2.1 井田地层.................................................................................................................. 13 2.2.2 井田构造特征.......................................................................................................... 16 2.2.3 含煤地层特征.......................................................................................................... 16 2.3 百子煤矿煤岩强度分析................................................................................................. 17 2.4 小结................................................................................................................................. 17 3 层间岩体及下伏煤柱稳定性理论分析 .......................................................................................... 19 3.1 采动压力的确定............................................................................................................. 19 3.1.1 采动压力计算公式的确定 ...................................................................................... 19 3.1.2 采动压力值的确定 .................................................................................................. 20 3.2 层间岩体稳定性分析..................................................................................................... 20 3.2.1 底板破坏深度的确定 .............................................................................................. 20 3.2.2 底板岩层应力的确定 .............................................................................................. 24 3.2.3 层间岩体稳定性分析.............................................................................................. 26 3.3 煤柱稳定性分析............................................................................................................. 27 3.3.1 煤柱承受荷载的确定.............................................................................................. 27目录 Ⅱ 3.3.2 煤柱强度的确定...................................................................................................... 27 3.3.3 煤柱稳定性系数的确定.......................................................................................... 29 3.3.4 煤柱稳定性分析 ...................................................................................................... 29 3.4 小结................................................................................................................................. 30 4 柱采区域煤柱支承压力变化特征研究 .......................................................................................... 31 4.1 模拟实验目的与设计..................................................................................................... 31 4.1.1 实验目的 .................................................................................................................. 31 4.1.2 实验设计.................................................................................................................. 31 4.2 模拟实验过程、现象及分析......................................................................................... 33 4.2.1 模拟 8 号煤层柱式开采煤柱支承压力变化情况 .................................................. 33 4.2.2 模拟 5 号煤层上行长壁开采煤柱支承压力变化情况 .......................................... 36 4.3 小结................................................................................................................................. 41 5 数值模拟研究 ........................................................................................................................................ 42 5.1 数值模拟的目的与模型设计......................................................................................... 42 5.1.1 数值模拟的目的 ...................................................................................................... 42 5.1.2 数值模拟模型设计 .................................................................................................. 42 5.2 数值模拟过程................................................................................................................. 43 5.2.1 8 号煤层开采数值模拟结果分析 ........................................................................... 44 5.2.2 5 号煤层开采数值模拟结果分析 ........................................................................... 45 5.3 层间岩体运移规律......................................................................................................... 48 5.4 小结................................................................................................................................. 51 6 结论 .......................................................................................................................................................... 52 致谢 ............................................................................................................................................................. 53