深部开采底板突水孕育过程多场非线性耦合效应基础研究

Floor water inrush of high confined water induced by deep mining of coal resources is major hidden trouble and technical problem of coal mine safety production in China. The research focuses on the floor aquifer and deformation features affected by mining of water-bearing floor with high pressure. Fracture network extensions of floor rock seam, the dynamics evolution of conductor and floor water inrush process under multi-field coupling effects of high confined water, high stress and high temperature caused by deep mining are systematically studied by using the method of investigation and analysis, field test, laboratory test, physical simulation and numerical simulation. The research contents are as follows: (1) the mechanical mechanism of floor water inrush in deep mining is revealed by establishing a multi-field coupling nonlinear dynamic model of the seepage field of deep rock mass mining stress field, temperature field and high confined water; (2) The fracture development law of the floor and formation process of water inrush channel affected by mining, and damage mechanism of mesh fracture and multi field nonlinear coupling effect are studied; (3) The theory of water inrush process is preliminarily established by studying the process of floor confined water inrush in deep mining; (4) The dynamic evolution process of deformation and failure form, movement process and destabilization induced water inrush disaster is revealed by computer simulation technology. The hydrodynamic mechanism of deep mining floor water inrush is revealed by solving the above basic scientific problems, which provides a theoretical foundation for deep mine safety exploitation.

深部煤炭资源开采诱导的底板高承压水突出是我国煤矿生产的重大隐患和技术难题。课题围绕煤层底板阻（隔）水岩层及高承压含水层受采动影响变形特点，采用调研分析、现场实测、室内试验、物理模拟、数值仿真等手段，对深井高水压、高地应力、高地温多场耦合效应下的底板岩层裂纹网化扩展、导水通道动力学演化及底板突水动力学过程进行系统研究，主要内容包括：（1）建立深部岩体采动应力场、温度场、高承压水渗流场多场耦合非线性动力学模型，揭示深部开采底板突水灾变力学机理；（2）研究受采动影响底板裂隙发育规律与突水通道形成过程、网化裂隙损伤机理及多场非线性耦合效应；（3）研究深部开采底板高承压水突出过程，初步建立过程化突水理论；（4）运用计算机模拟仿真技术揭示底板岩层变形破坏形式、运动过程和破坏失稳诱发突水灾害发生的动态演化过程。通过解决上述基础科学问题，揭示深部开采底板水突出动力学机理，为深部矿井安全开采提供理论基础。

矿井突水灾害是威胁我国煤矿安全生产的重大隐患和技术难题。随着浅部煤炭资源的日益枯竭，煤炭的开采深度逐渐增大，深部煤炭资源开采过程中的热（thermal）、水（hydrological）、力（mechanical）是影响底板阻（隔）水岩层力学性能的三个主要因素，三者之间相互作用，形成了岩体温度场、渗流场和应力场（简称 THM）的多场耦合效应。应力–渗流耦合作用是突水形成过程中的驱动因素，由线性渗流向非线性渗流的转变是突水发生时地下水流态变化的标志，而渗流导致的地温变化可以用来表征突水形成过程中的地下水流态的变化，多孔介质是上述各因素在破裂岩体内相互作用的媒介。研究团队综合采用现场调研、理论分析、实验研究、数值模拟等方法，研究了THM多场耦合作用下煤层底板水非线性突出动力学机理，取得的研究成果和得出的主要结论如下：（1）开展了基于核磁共振技术的水岩作用下岩石损伤特征实验研究，得到了不同时间段岩石的孔隙结构演化规律，动态的展示了岩石损伤演化过程；（2）开展了应力–渗流耦合作用下破裂岩体非线性渗流实验，并得出了非线性渗流演化规律，建立了地下岩体应力场-温度场-高承压水渗流场（THM）多场耦合数值模型；（3）建立了基于非线性突水孕育过程的临界压力梯度突水危险性判据，并应用于实际的矿井底板突水预测评价；（4）建立了考虑非线性渗流作用的破裂岩体THM耦合突水动力学模型；（5）通过数值模拟研究了多场耦合作用下底板突水动态演化过程以及非线性突水过程中的温度场响应特征。通过上述研究，揭示了多场耦合作用下深部开采底板水非线性突出动力学机理，对预测评价突水危险性具有重要的理论和现实意义。