层次结构底板次生断裂构造活化突水致灾机理基础研究

There has been a cognition to the fact that nearly 70% of the mine inrush disasters are related to the structure. But seldom research on water inrush caused by secondary fracture activation near the main fracture is done,even less is the research on the influence of combined fracture and hierarchical structure.The problem is water inrush caused by the activation of the secondary fracture within the layered floor was more elusive and pernicious. Starting from the strata lithology and its hierarchy combination and secondary fracture extension, the geological mechanics model with appropriate sedimentary characteristics was built. Explore the layered fracture criterion of hierarchy combination floor. Through similar material simulation and shear seepage experiment, study of the multi-level hierarchy floor lithological variation of secondary fracture and interlayer fissure under the influence of mining pressure and confined water, together with research on the influence of combined fracture and hierarchical structure to secondary fracture activation extension and relevance with water inrush due to forming inrush conduit, contribute to the space-time evolution process of secondary crack and interlayer fissure extending, linking and forming inrush conduit. Through analyzing the most likely disaster-causing rock composite structures due to secondary activation and interlayer fissure forming inrush conduit, it can reveal the water inrush destructive mechanism of secondary crack and interlayer fissure forming inrush conduit under the effect of the stress field and the seepage field, which is of great significance in the improvement of the mine water inrush control theory, ensuring mine safety.

矿井底板突水灾害约70%与构造有关，对此问题已有所认知，但对主要断裂附近次生断裂活化突水研究甚少，考虑底板层次组合协同作用的研究更少，而次生断裂构造活化突水极具隐蔽性，造成的危害更严重。课题从岩层岩性及其层次组合和次生断裂构造生成扩展入手，建立适宜沉积特征的地质力学模型，推求采场底板类似多层复合板的分层破断准则；结合相似材料模拟和剪切渗流实验深入研究多岩性组合层次底板次生裂隙和层间裂隙在矿山压力及承压水作用下渗透性的特征，研究多断裂组合、层次组合结构对次生裂隙活化扩展程度的影响及其与形成突水通道而突水致灾的关联作用，以获得次生断裂裂隙与层间裂隙扩展、贯通形成突水通道的时空演化过程，分析最易因次生断裂构造活化与层间裂隙贯通形成突水通道而致灾的岩层组合结构，揭示矿井底板在次生断裂构造在应力场渗流场作用下扩展活化形成突水通道而突水致灾的机理，这对完善突水防治理论，保障矿井安全生产具有重要意义。

针对层次结构底板次生断裂构造活化突水致灾机理基础研究这一科学命题，分析确定了层合岩性底板临界损伤破坏层的位置，建立了层次结构底板采动破坏深度的理论解析公式；通过对自制的“类断层破碎带裂隙岩体”的多场渗透特性试验和主次断层不同对应关系与次生断层多种参量的类岩石材料单轴、真三轴实验，获知了不同条件下类断层破碎带裂隙岩体的裂纹扩展与渗透性特征、多场效应及其演化过程；以独有专利技术，利用构建的可考虑多场耦合效应的相似材料模型进行了开采动态的精细模拟，得到了采动效应下次生断层变形破坏的过程及程度；分析了采动诱导次生断层活化的动力学过程，确立了次生断层活化临界突水力学判据；借助COD方法，分析了水压力对断层张开量的影响规律，构建了含主次断裂构造的突水动力学模型，利用FLAC3D-FLUID-MECHANICAL耦合模块提供的平台，对所建模型进行了二次开发模拟，获得了不同参数响应间的关系与渗流对其的蚀损弱化程度等宏细观力学特征；提出了采动场效应诱导下次生断层活化突水机制；完成了主次断层影响因素的排序；基于模糊物元理论、未确知-熵权理论及Fisher理论方法，利用GIS多源地学信息复合叠加方法，建立了不同模式下多因素致灾的断裂活化突水预测模型，提高了采动效应诱导下主次生断层活化突水的预防预控效果。本项目成果进一步完善了主次生断层活化突水致灾机理，丰富了煤矿水灾害预防预控理论。.在本项目执行期间，共发表学术论文30篇，其中SCI、EI检索15篇，核心期刊12篇，出版专著3部，申请和授权国家发明专利14项，获得省部级科研奖励7项。本项目研究成果已在地质构造复杂的恒源公司、五沟煤矿等多个煤矿等进行了推广应用。实践证明，依据本项目成果既能有效预防主次断层活化突水事故的发生，重新留设的断层防水煤柱又能提高煤炭回收率，具有很大的实际应用价值，且可为类似地质条件下煤矿安全生产提供重要的科学依据。