【作者】 卜万奎；

【导师】 缪协兴；

【作者基本信息】 中国矿业大学 ， 工程力学， 2009， 博士

【摘要】 矿井突水灾害预测与防治一直是我国煤矿安全生产的重大研究课题,底板断层突水是煤矿突水事故的主要形式,采动引起底板断层活化、进而与采场底板采动裂隙形成导水通道,是引发矿井突水事故的重要原因。本文运用理论分析、实验测试、数值模拟和现场实践等手段,系统研究了采动引起底板断层活化及突水的力学机理,取得了如下具有创新性的成果:(1)利用专用的裂隙岩石和破碎岩石渗透性测试系统,测定了断层带围岩的渗透特性,结果表明:峰后破碎岩石和原位破碎岩石的渗透系数较一般裂隙岩石大1～3个量级;轴压和围压对破碎岩样的渗透性均有较大程度的抑制作用,使其渗透系数减小。研究成果对揭示断层带活化及突水机理具有重要作用。(2)针对采动引起底板断层活化及突水的力学特征,建立了采场底板活化机理分析的力学模型,得到了断层围岩的应力场分布规律,给出了底板断层活化的剪应力判据,分析得到了采深、断层倾角、断层落差、采场推进方向、工作面支承压力的集中程度等因素对底板断层活化的影响规律。(3)应用控制体积法,建立了断层带裂隙内水流的动力学控制方程,分析给出了裂隙内水压的分布规律。在此基础上,应用断裂力学理论研究了含孔隙水压作用断层带裂隙的扩展特征,给出了相应的裂隙扩展判据。研究得到了拉剪复合型裂隙、压剪复合型裂隙的有效应力强度因子随裂隙水压的变化规律。(4)应用数值模拟方法,研究了采动影响下底板断层活化及渗流场特征,得到了断层活化范围和渗流速度随断层倾角、断层落差、承压水水压的变化规律,比较了正断层与逆断层两种条件下底板断层活化与渗流特征的异同,初步给出了含断层带压开采情况下防水煤柱的确定方法。研究成果成功地用于某矿区含断层工作面突水危险性预测与防治实践,取得了显著的社会和经济效益,也为类似工程条件下矿井突水防治提供参考。该论文有图119幅,表26个,参考文献177篇。更多还原

【Abstract】 The prediction and prevention of water inrush accidents in coal mine has always been one significant subject of safe mining production in china, in which water inrush from faults in floor is one main style. In the process of mining, faults in floor are likely to be activated and link to mining-induced fissures to form water channel, which is one important reason that induces many water inrush accidents in coal mines. In this thesis, different study methods including theoretical analysis, experimental test, numerical simulation and field practice are applied to systematically research the mechanical mechanism of water-inrush with fault activated by mining in floor, and obtain the following innovational results:The permeability property of rock around fault zone is measured by using permeability measurement system for rocks with fissures and broken rocks, which indicates that: compared with common rock with fissures, the permeability of post-peak borken rock and in situ can reach up to 10 to 1000 times of that; the premeability of broken samples is greatly controlled by axial and surrounding pressures. The study results can play an important role in revealing mechanism of water-inrush induced by fault activation.According to the mechanical characteristics of water inrush form faults activated by mining, mechanical model on mechanism analysis of fault activation in mining floor is built, obtaining stress field distribution rule of rock around fault, giving out shear stress criterion for falut activation in floor, analyzing the effect of factors, such as mining deepth, fault dip, fault throw, advance direction, concentration degree of supporting force in working face, on rule of fault activation in floor.Control volume method is applied to build dynamical control equation for water flow in fissures of fault zone, analyzing and presenting the distribution rule of water pressure in fissures; based on this, the propagation characteristics of fissures under the effect of pore pressure in fault zone is studied by using fracture mechanics theory, and give the corresponding criterion for fissure propagation; getting the change rule for effective stress strength of tension-shear compound fissures, compaction-shear compound fissures along with fissure water pressure.Numerical simulation method is also applied to study fault activation in mining floor and characteristics of seepage field, obtaining scope of fault activation as well as change rule for seepage velocity along with fault dip, fault throw, confined water pressure, comparing the difference and similarity on falut activation and seepage characteristics under the two different conditions of normal fault and reverse one, and primarily finding the determination method for water-proof coal pillar under the situation of mining floor with fault above confined water.The research results have been successfully applied in the water inrush prediction and prevention practice of working face with fault in a certain mining area, and created significant social and economic value, which can provide reference for the prevention of water inrush in mining area with the similar engineering condition.There are 119 figures, 26 tables and 177 references in this thesis.更多还原