Basic experimental research on the delineation of the evolutionary process of fault water inrush
SUN Wenbin;YANG Hui;ZHAO Jinhai;XUE Yandong;ZHANG Xiaobo;LIU Qianhui
断层突水严重威胁煤矿开采,灾害呈滞后性、隐蔽性等特征,掌握断层突水灾变演化机制、过程规律,对开展煤矿防治水工作具有重要理论指导意义。通过构建突水演变分析模型,分析了承压水导升路径和断层带演化特征。釆用岩石应力−渗流耦合真三轴试验系统,结合声发射和数字散斑技术,配制含断层破碎带充填物的大尺寸类岩石试样,研究了双轴加载过程中含不同岩性和产状断层充填物的试样失稳破坏特征,获得了声发射事件和试样变形特征,最后采用改造升级的采动底板突水模拟试验系统和应力、水压、并行电法在线监测子系统,室内再现了采动断层突水演变全过程,获得了各监测参数演变特征。研究结果表明:断层带受开采扰动响应更强烈,更容易破坏失稳为承压水导升提供空间;断层充填物的性质决定了断层活化的强度和难易程度,将一定程度上影响断层突水的时空演化过程;断层尖端受流固耦合作用明显,断层带及隔水层产生的裂隙经历萌生—扩展—贯通阶段,断层与工作面的相对位置关系决定了断层演化带和底板破坏带对接的时空位置;根据承压水导升路径,将断层突水过程划分为“断层活化”“贯通导水”“‘双带’(断层演化带与底板破坏带)对接”3个灾变演化阶段,实现了断层突水演化过程的阶段划分。
Coal mining is seriously threatened by fault water inrush, showing the disaster characteristics of hysteresis and concealment. Mastering the evolution mechanism and process law of fault water inrush disaster has important theoretical guiding significance for carrying out deep water prevention and control work. By constructing water inrush evolution analysis model , the conduction path of confined water and the evolution characteristics of fault zone are analyzed. Using true triaxial rock test system of coupled stress-seepage , combined with acoustic emission and digital speckle technology, large-size rock-like specimens containing fault fracture zone fillings were designed. The instability and failure characteristics of specimens with different lithologic fillings and fault occurrences during biaxial loading were studied. The acoustic emission events and specimen deformation characteristics were obtained. Finally, the modified and upgraded mining floor water inrush simulation test system and parallel electrical on-line monitoring, stress and water pressure monitoring subsystems were used to reproduce the whole process of mining fault water inrush evolution in the laboratory, and the evolution characteristics of monitoring parameters were obtained. The results show that the response of fault zone to mining disturbance is stronger, and it is easier to destroy and destabilize to provide space for confined water conduction. To a certain extent, the nature of fault fillings determines the difficulty of fault activation, then affects the temporal and spatial evolution process of fault water inrush. The fault tip is obviously affected by fluid-solid coupling. The cracks generated by the fault zone and the aquiclude undergo the initiation-expansion-through stage, the relative position relationship between the fault and the working face determines the time and space position of the fault evolution zone and the floor failure zone. According to the conduction path of confined water, the process of fault water inrush is divided into three stages : ‘ fault activation, water conduction, ’ double zone ‘ ( fault evolution zone and floor failure zone ) docking ’, the stage delineation of fault water inrush evolution process are realized.
fault;water inrush channel;fault activation;fault fillings;similar simulation;disaster characteristics;water-inrush
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会