耿村煤矿煤层开采对逆冲断层影响特征研究

发布时间：2018-08-25 11:36

【摘要】：煤矿开采扰动了煤层和顶底板岩层,破坏了原岩体的应力平衡状态;逆冲断层破坏了煤层的连续性,当煤层开采时逆冲断层附近围岩应力升高,局部岩体出现滑移变形失稳。逆冲断层活化有可能诱发煤矿采场发生冲击矿压,严重时造成人员伤亡事故。论文以耿村煤矿逆冲断层为工程地质背景,建立了数值计算力学模型,研究了断层倾角、落差和破碎带宽度,煤层采高、采深,以及煤层开采过程等地质和开采参数,对工作面前方支承压力、顶板下沉量、断层面正应力、剪应力及滑移量等因素的影响规律,研究了活化逆断层采场发生断层冲击矿压的机理。结合逆冲断层两盘“解锁”滑移的力学理论分析,研究了逆断层上、下两盘在水平构造应力及垂直应力共同作用下的启滑条件和滑移规律,初步提出了断层滑移的临界危险区域,并分析煤层开采、断层“活化”与冲击矿压之间内在关系。最后,根据耿村煤矿12220综放工作面在探巷掘进时,揭露F_(16)逆冲断层的特征,数值模拟煤层开采对F_(16)逆冲断层活化的影响,以及活化逆冲断层对工作面推进过程的影响。通过数值模拟、理论分析和现场实际监测得出结论,随着煤层开采范围的不断扩大,工作面越接近断层,断层带应力集中和滑移运动就越明显,应力和能量也不断积累;当活化断层附近围岩达到极限强度时,就会以剧烈方式释放积累的弹性能冲击采煤工作面,诱发断层冲击矿压的发生。总之,煤层开采是断层“活化”的前提条件,采场煤岩体承载力的减小或丧失是引起断层滑移的直接原因,断层滑移引起的冲击效应是采场大范围冲击失稳的原因。论文研究结论对于预测和预防综放工作面冲击矿压具有一定的指导意义。
[Abstract]:Coal mining disturbs coal seam and roof rock, destroys stress balance of original rock mass, and thrusting fault destroys continuity of coal seam. When coal seam is mined, surrounding rock stress increases and local rock mass appears slip deformation instability. Thrusting fault activation may induce coal mine stope to impact rock pressure and cause casualties when serious. Taking the thrust fault of Gengcun Coal Mine as the engineering geological background, a numerical computational mechanics model is established, and the geological and mining parameters such as fault dip angle, drop and width of broken zone, coal seam mining height, mining depth and coal seam mining process are studied. The mechanism of rock pressure impact on active reverse fault stope is studied by influencing factors such as supporting pressure, roof subsidence, normal stress, shear stress and slip in front of working face. Based on the mechanical theory analysis of "unlocking" slip on two plates of thrust fault, the starting and sliding conditions and slip law of the next two plates on the reverse fault under the combined action of horizontal tectonic stress and vertical stress are studied. The critical danger area of fault slip is put forward preliminarily, and the internal relationship between coal seam mining, fault "activation" and rock burst is analyzed. Finally, according to the characteristics of F16 thrust fault, the influence of coal seam mining on the activation of F16 thrust fault and the influence of activated thrust fault on the working face propulsive process, the characteristics of F16 thrust fault are exposed in 12220 fully mechanized caving face of Gengcun Coal Mine. Through numerical simulation, theoretical analysis and field monitoring, it is concluded that with the continuous expansion of the mining area of coal seam, the closer the working face is to the fault, the more obvious the stress concentration and slip movement in the fault zone will be, and the stress and energy will be accumulated. When the surrounding rock near the activated fault reaches the ultimate strength, the accumulated elastic energy will be released in a violent way to impact the mining face, which will induce the occurrence of the rock pressure impact of the fault. In a word, coal seam mining is the precondition of fault activation, the reduction or loss of bearing capacity of stope coal and rock mass is the direct cause of fault slip, and the impact effect caused by fault slip is the cause of large-scale impact instability in stope. The conclusion of this paper has certain guiding significance for prediction and prevention of rock burst in fully mechanized caving face.
【学位授予单位】：河南理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD324

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