巨厚煤层开采覆岩破坏规律及地表变形研究
发布时间：2018-09-08 06:18
【摘要】：我国西北部地区巨厚煤层分布较广,煤层开采后覆岩移动及地表下沉规律与一般厚度煤层的相比具有很大的差异性。论文针对鄂尔多斯地区煤层厚度大,地表多为黄土层所覆盖等特殊地质条件,结合不连沟煤矿典型工作面采后地表下沉现象,综合运用现场踏勘、理论分析、相似材料试验和数值模拟等方法,对该地区巨厚煤层开采覆岩移动及地表下沉特征进行了系统研究。论文主要取得了以下研究成果:(1)结合不连沟煤矿覆岩结构,运用关键层理论,得到了不连沟煤矿6#煤层顶板覆岩中存在的关键层数量、初次破断及周期破断规律,并结合失稳条件,给出了关键层破断岩块形成结构的失稳形式。(2)分析巨厚煤层开采特点,建立了高位短悬臂梁-台阶岩梁的力学模型,推导出了该结构不发生滑动失稳所需支撑力的表达式,带入相关参数后得出,巨厚煤层大采高采场顶板需要更大的支护强度。(3)区域内巨厚煤层采后覆岩只存在两带即垮落带和裂缝带;通过现场观测、数值模拟及相似材料模拟得出关键层对导裂带发育、地表沉陷等起控制作用,采后在工作面两侧及切眼一侧覆岩破断后沿垮落角方向的裂隙明显,裂缝宽度大,薄基岩矿区导裂带包络线呈正梯形。
[Abstract]:Thick coal seams are widely distributed in Northwest China, and the laws of overlying strata movement and surface subsidence after coal mining are quite different from those of common thick coal seams. The subsidence phenomenon is studied systematically by using the methods of field investigation, theoretical analysis, similar material test and numerical simulation. The main research results are as follows: (1) Combining with the overburden structure of Duangou Coal Mine, the key stratum theory is applied to get the Duangou Coal Mine. 6 # coal seam roof overburden in the number of key strata, the first break and periodic break law, combined with instability conditions, the formation of key strata broken rock block structure of the instability form. (2) analysis of the mining characteristics of thick coal seam, the establishment of a high-level short cantilever beam-bench rock beam mechanical model, derived the structure of the sliding instability. The expression of supporting force is introduced, and it is concluded that the roof of large mining height stope in huge thick seam needs more supporting strength. (3) There are only two zones of collapse zone and fracture zone in the overlying strata of huge thick seam after mining. Through field observation, numerical simulation and similar material simulation, it is concluded that the key strata control the development of leading fracture zone and surface subsidence. After mining, the cracks along the caving angle direction are obvious on both sides of the working face and one side of the cut hole, and the width of the cracks is large, and the envelope of the fracture conduction zone in the thin bedrock mining area is normal trapezoidal.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TD325
本文编号：2229626
[Abstract]:Thick coal seams are widely distributed in Northwest China, and the laws of overlying strata movement and surface subsidence after coal mining are quite different from those of common thick coal seams. The subsidence phenomenon is studied systematically by using the methods of field investigation, theoretical analysis, similar material test and numerical simulation. The main research results are as follows: (1) Combining with the overburden structure of Duangou Coal Mine, the key stratum theory is applied to get the Duangou Coal Mine. 6 # coal seam roof overburden in the number of key strata, the first break and periodic break law, combined with instability conditions, the formation of key strata broken rock block structure of the instability form. (2) analysis of the mining characteristics of thick coal seam, the establishment of a high-level short cantilever beam-bench rock beam mechanical model, derived the structure of the sliding instability. The expression of supporting force is introduced, and it is concluded that the roof of large mining height stope in huge thick seam needs more supporting strength. (3) There are only two zones of collapse zone and fracture zone in the overlying strata of huge thick seam after mining. Through field observation, numerical simulation and similar material simulation, it is concluded that the key strata control the development of leading fracture zone and surface subsidence. After mining, the cracks along the caving angle direction are obvious on both sides of the working face and one side of the cut hole, and the width of the cracks is large, and the envelope of the fracture conduction zone in the thin bedrock mining area is normal trapezoidal.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TD325
【参考文献】
相关期刊论文 前1条
1 钱鸣高，缪协兴;采场上覆岩层结构的形态与受力分析[J];岩石力学与工程学报;1995年02期
，本文编号：2229626
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