急倾斜煤层开采地表沉陷分区模式与协调式岩层控制技术研究

With the depth of mining, the coal mining problem of steep coal seam mine under railways, buildings and water bodies is increasingly more serious. The problem causes the loss of coal resources, affects the mining life of the mine and also restricts the development and maintenance of coal production. Compared to slowly inclined coal seam, the steep coal seam occurrence condition is complicated and influence factor is numerous. The surface especially the outcrop collapse area is destroyed seriously and it is easily to form discontinuous step crack. Surface subsidence rule and strata control problem of steep coal seam are complicated. This subject used the steep thick coal seam as the research object will propose the measured data analysis, similar material model test, numerical simulation, theoretical prediction analysis and other research methods to establish the whole ground basin zone mode of the steep coal seam mining. The research will reveal the surface subsidence and deformation characteristics of each zone and the development mode of surface subsidence existing zone with the mining depth. The occurred conditions of outcrop collapse area will be determined. The mining influences function of the high-rise structures and low-rise buildings in different subsidence zones will establish based on the tilt and tensile deformation as evaluation indexes. Strata damage rule of the steep coal seam mining is revealed, and the not fully exploitation principle and the analysis of stability of coal pillar are applied to study the mining strata control technology of coordinate mining. This research can provide a reference basis and a safe and efficient new way for the steep coal seam mine under the railways, buildings and water bodies.

随着开采深部化，我国急倾斜矿井“三下”压煤问题日益严重，不仅造成了煤炭资源的损失，而且影响着矿井的开采寿命，制约着煤炭的生产维持和发展。相比缓倾斜，急倾斜煤层赋存条件复杂、影响因素多、变化大，地表特别是露头区破坏严重，易形成非连续台阶状裂缝，导致其地表沉陷规律与岩层控制问题比较复杂。本课题针对这一问题，以急倾斜中厚煤层为研究对象，采用现场实测数据分析、相似材料模型试验、数值模拟和理论预测等方法开展如下研究：建立急倾斜煤层开采地表全盆地沉陷分区模式，探讨各沉陷分区移动变形特征，以及采矿深部化地表已有沉陷格局的发展变化模式，确定露头塌陷区的出现条件；以倾斜和拉伸变形为评价指标，探讨各分区内高耸构筑物和低层建筑物的采动影响函数关系；揭示急倾斜煤层开采覆岩破坏规律，基于走向非充分开采原理和煤柱稳定性分析进行协调式岩层控制技术研究。本课题研究成果将为安全高效开采急倾斜“三下”压煤提供依据和新途径。

我国急倾斜煤层储量丰富、分布范围较广，涵盖华亭、北京、淮南、乌鲁木齐等多个矿区，已形成相当的开采规模，其节理发育、底面光滑、变质程度高，多为无烟煤，煤质优良，具有很高的开采价值。目前，水平煤层以及缓倾斜和倾斜煤层的地表沉陷预计方法和地表移动变形规律研究成果比较丰富，而急倾斜煤层赋存条件复杂，上覆岩层与地表移动变形和破坏均比较剧烈，沉陷规律具有独特性，其沉陷内部机理和地表移动变形规律的研究成果均较少。.本项目以京西大台矿、华亭东峡矿等急倾斜矿井煤层开采为研究对象，采用地表实测数据分析、理论分析、相似材料模型实验和数值模拟等方法，进行了急倾斜煤层开采地表沉陷分区模式与协调式岩层控制技术的研究。主要研究内容为急倾斜煤层开采后地表全盆地沉陷分区模式及其特征研究；各沉陷分区内建（构）筑物变形的采动影响规律研究；急倾斜煤层开采岩层破坏规律与协调式控制技术研究。通过系统的研究，得出了地表移动盆地分为地表露头非连续变形区、整体沉降区、渐变沉降区和轻微沉降区4个区域，并分析了各沉陷分区的特点。揭示了煤层倾角和煤层厚度与地表沉陷分区变化的影响关系，建立了各分区范围和分区角随煤层倾角、煤厚、阶段垂高变化的计算公式。建立地表全盆地沉陷分区模式，揭示了急倾斜煤层开采地表各沉陷分区的倾斜和水平变形的特征，分析了各沉陷分区内低层建筑物与高耸构筑物的采动影响规律，建立了相应的函数关系。全面揭示了浅部和深部开采时覆岩破坏的形态、大小、范围、传播方向和相互影响关系等规律，得出地表沉陷分区的形成机理。从采区布置方式、开采顺序、开采方法、采区间协调开采等方面研究协调式开采的岩层控制技术，应用走向非充分开采原理和煤柱稳定性，优化采区和煤柱的尺寸，改善煤柱回采过程中的地表变形分布和沉陷分区位置，控制地表动态变形值，提出了急倾斜煤层群深部跨采区协调开采技术。研究成果为急倾斜“三下”压煤开采提供了依据和新途径。