特厚煤层开采冲击地压机理与防治研究

发布时间：2018-06-09 21:27

本文选题：特厚煤层 + 综放工作面　；参考：《北京科技大学》2017年博士论文

【摘要】：针对近年来我国80%以上冲击地压事故均发生在特厚煤层采掘工作面的现状,急需在理论上揭示特厚煤层更容易发生冲击地压的机理,从而为特厚煤层的开采设计、冲击地压防治和预警提供理论和技术支撑。本文以新疆、山东矿区多起特厚煤层严重冲击地压事故为工程背景,采用现场实测、理论分析、案例调研、岩石力学试验、数值模拟等手段,围绕特厚煤层孕灾时间长、易发生"工作面与两道同时冲击"的整体性冲击灾害、冲击与大变形同时致灾等共性问题,系统研究了特厚煤层典型冲击地压发生机理和防治技术,取得了如下成果:(1)研究了特厚煤层两种典型冲击地压(卸荷型冲击和蠕变型冲击)的发生机理。建立了不同厚度煤层巷道围岩能量释放计算方法,提出了以煤体冲击倾向性和动静应力比值为基础的冲击危险性评价方法,揭示了特厚煤层围岩分区蠕变特征,并推导出了各分区蠕变范围的计算公式,为特厚煤层的开采设计、冲击地压防治提供了理论基础。(2)研究了孤岛工作面发生整体蠕变失稳型冲击地压的机理及全过程。建立了孤岛工作面载荷传递估算模型和煤层承载力计算模型,提出了孤岛工作面整体失稳型冲击危险评估方法,为孤岛工作面整体蠕变失稳型冲击危险性评估及防治提供了理论基础。(3)提出了深井特厚煤层冲击地压与大变形协调控制机制。揭示了深井特厚煤层综放工作面基本顶二次破断回转诱发沿空巷道大变形的力学机制,推导出了基于能量耗散指数法的防冲钻孔参数定量计算方法,提出了 "分区分级"的冲击地压防治理念,研发了新型双立柱单元式超前支架,实现了深井特厚煤层冲击地压与大变形协调控制。(4)提出了特厚煤层开采过程中典型冲击危险区的冲击机制和防冲技术。研究了深井特厚煤层综放工作面过联络巷强烈动压区的致灾机理,揭示了深井特厚煤层综放工作面断层活化规律,并将其分为应力显现阶段、蓄能阶段和结构活化阶段三个阶段,建立了深厚表土薄基岩综放采场充分采动条件下支承压力分布特征估算模型,为深井特厚煤层综放工作面防冲开采设计提供了理论基础。
[Abstract]:In view of the fact that more than 80% of the impact ground pressure accidents occur in the mining face of super thick coal seam in China in recent years, it is urgent to reveal theoretically the mechanism of the impact ground pressure in extra thick coal seam, so as to design the mining of extra thick coal seam. Shock pressure prevention and early warning to provide theoretical and technical support. In this paper, based on the engineering background of several severe shock and ground pressure accidents in thick coal seams in Xinjiang and Shandong mining areas, field measurement, theoretical analysis, case investigation, rock mechanics tests, numerical simulation, etc., are adopted, and the disaster occurrence time is long around the extra thick coal seams. The common problems such as "working face and two roads impact at the same time" are easy to occur, and the common problems such as simultaneous impact and large deformation are discussed. The occurrence mechanism and prevention technology of typical impact ground pressure in ultra-thick coal seam are systematically studied. The following results are obtained: 1) the occurrence mechanism of two typical impact ground pressure (unloading impact and creep impact) in ultra-thick coal seam is studied. The calculation method of energy release of surrounding rock of roadway with different thickness is established, and the impact risk assessment method based on the impact tendency of coal body and the ratio of dynamic and static stress is put forward, and the zone creep characteristics of the wall rock of extra thick coal seam are revealed. The calculation formula of creep range in each zone is deduced, which provides a theoretical basis for mining design of extra thick coal seam and the prevention and control of impact ground pressure. (2) the mechanism and the whole process of the whole creep-instability impact ground pressure occurring in the isolated island face are studied. The load transfer estimation model and the coal bearing capacity calculation model of the isolated island face are established, and the assessment method of the whole unsteady impact hazard of the isolated island working face is put forward. This paper provides a theoretical basis for the assessment and prevention of the whole creep-instability impact hazard in the island face) and puts forward a coordinated control mechanism between the impact ground pressure and the large deformation of the deep and extra thick coal seam. This paper reveals the mechanical mechanism of the large deformation of roadway along goaf induced by the secondary breaking and turning of the basic roof of the fully-mechanized caving face in the deep and extra thick coal seam, and deduces the quantitative calculation method of the parameters of the anti-scour borehole based on the energy dissipation index method. This paper puts forward the concept of "zonal classification" for the prevention of impact ground pressure, and develops a new type of double column unit lead support. The impact mechanism and anti-scour technology of typical impact risk area in the mining process of ultra-thick coal seam are put forward in this paper, which realizes the coordinated control of rock burst and large deformation in deep and ultra-thick coal seam. In this paper, the mechanism of disaster caused by the strong dynamic pressure in the overpass roadway of fully-mechanized caving face in deep and extra thick coal seam is studied, and the law of fault activation in fully-mechanized caving face of ultra-thick coal seam in deep well is revealed, and it is divided into the stage of stress manifestation. In the three stages of energy storage stage and structure activation stage, a model for estimating the distribution characteristics of supporting pressure under the condition of full mining of deep topsoil and thin bedrock in fully mechanized caving stope is established, which provides a theoretical basis for the design of full-mechanized top-coal caving face in deep and thick coal seam.
【学位授予单位】：北京科技大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TD324

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