深部底板断层滑移诱发裂隙纵横演化滞后突水机理研究

The safety mining of coal seam above deep high confined water is the realistic problem demanding prompt solution for green mining, and safe and efficient energy system in Chinese mining area. According to present mining situation above high confined water in east China, aiming at special environment of high stress, strong seepage and high water pressure, the methods of simulation test of fault cracks evolution, true triaxial test of prefabricated crack propagation in specimens with large size, theoretical research, and field measurement were carried out to study the lagging water inrush mechanism due to cracks evolution by crossbar induced by floor fault slip of deep mining. The main research contents are as follows: (1) the development characteristics of cracks due to floor fault slip under high stress was studied through developed test system to simulate fault cracks evolution based on similar simulation test system of floor water inrush with mining coal seam; applying the true triaxial rock test system with coupled stress-seepage, the law of crack penetration modes between strata with different lithology and propagation evolution within strata of cracks prefabricated in specimens with large size toward cavity were analyzed; (2) the coupling rheology-seepage mathematical model of fault crack was established under high water pressure; (3) the cracks features of deep floor fault were measured under long loading to verify the correct of theory and test research results. The research results of project contributes to perfect the lagging water inrush theory, and has widely guiding significance and application prospect for safely mining the coal seam above high confined water and water inrush prediction of deep mining.

深部高承压水上煤层安全开采是当前我国矿区实施绿色开采战略和建立安全高效能源体系急需解决的现实问题。结合我国华东地区深部高承压水上的采煤现状，针对深部高应力、强流变和高水压等特殊环境，本项目采用断层裂隙萌生演化模拟试验、大尺寸试样裂隙扩展真三轴试验、理论分析和现场实测验证相结合的方法，对深部底板断层滑移诱发裂隙纵横演化滞后突水机理进行如下研究：（1）改制断层裂隙萌生演化模拟试验系统，研究高应力作用下底板断层滑移诱发裂隙的发育特征；借助岩石应力-渗流耦合真三轴试验系统，分析大尺寸试样裂隙向空洞演化的岩层内扩展和岩层间贯穿的规律及渗流特性；（2）建立高水压下断层裂隙的流变-渗流耦合数学模型；（3）现场实测长时加载下深部底板断层裂隙的发育形态，验证理论及试验结果的正确性。项目研究结果有利于完善深部滞后突水理论，对我国深部高承压水上的煤层安全开采和突水预测具有广泛的科学意义和应用前景。

基于我国华东地区深部高承压水上的采煤现状，针对深部开采面临的高应力、强流变和高水压的特殊环境，本项目采用底板突水相似材料模拟试验、大尺寸试件裂隙演化真三轴试验、理论分析和现场注浆试验相结合的方法，对深部底板断层滑移诱发裂隙纵横演化滞后突水机理进行了如下主要研究。.采用大尺寸试件裂隙演化真三轴试验，系统分析了双轴加载速率对大尺寸岩体破裂的影响规律，获得了同一岩性大尺寸试样裂隙在高三维应力作用下的演化规律，揭示了加载过程中单裂隙和双裂隙试样的破裂和声发射行为特征；将深部底板采动岩体裂隙分为剪切裂隙、层向裂隙和竖向张裂隙，利用力学知识演算获得了三种类型岩体裂隙的起裂准则，将深部底板突水灾变模式划分为完整底板裂隙扩展型、原生通道导通型和隐伏构造滑剪型，并分析了对应的突水判据，提出了相应的可行的深部开采突水预防和控制技术；借助底板突水相似材料模拟试验，建立了深部承压水上含断层底板裂隙演化及导水通道的形成模型，获得了底板裂隙演化及破裂规律；现场提出了“梅花式”和“上下穿层式”的黄河北煤田灰岩含水层分支钻孔钻进方式和井上、下水文观测孔水压实时监控的精准注浆技术，实现了含水层裂隙及隐蔽导水通道的有效探查封堵和注浆范围的精准控制；提出了模拟深部断层形成及裂隙发育的多功能试验方法，实现了深部高应力加载下岩体裂隙发育、演化致断层活化的全过程可视化模拟；设计了一种煤层底板含水层水压动态实时监测技术，实现了底板含水层水压的实时智能监测。.项目研究结果有利于完善深部底板突水理论，对高质量精准注浆治理顶底板灰岩水害解放黄河北煤炭资源具有重要的借鉴意义和指导作用，对我国深部高承压水上煤炭的安全开采和突水灾害的科学防控具有广泛的社会意义和应用前景。