采场围岩变形破断发育多场响应及其全程时空演化规律研究

The failure characteristic value of the surrounding rock deformation in coal mining field is a key parameter during the coal mine safety production. At present most of the obtained characterstic value of rock deformation is the two-dimension static state data value. But to grasp the spatio-temporal evolution regularity of the whole course in rock deformation is significant for the theoretical research of the rock stratum controlling and mine water prevention. On the basis of the stratum and structural condtions of A group coal seam floor in Huainan coal mine field, the technology of the distributed optical fiber and parallel electrical method are adopted in the task. Through the different methods such as rock experiment, numerical simulation, physical simulation and data analyzing of field monitoring, the aim is to reveal the response characteristic of strain field and electric field during deformation and failure of different rocks in the loading condition. The response relation between rock stress and crack developing state and its physical property parameters should be set up, and the distinguishing threshold value of failure must be established. Then through researching and developing the integration data collecting device of the distribution optical and earth electricity information in drilling hole, the 3D geologic model of A group coal seam mining is structured, and the fracture evolution information in whole time frame of surrounding rock deformation during the front, underway, subsequent of coal mining can be monitored in real time. Combining with the strain and earth electrical information data through field measurement in the top and floor rock of the working face during coal mining, the lateral zones of surrounding rock in the process of mining, such as the ahead bearing stress, separation layer caving, repetition compaction, can be divided, and the vertical zoning characteristic, such as direct caving, separation layer crack development, bending deformation, can be analyzed subtly. The 3D spatio-temporal evolution form of deformation and fracture about surrounding rock in the mining process can be recovered, and its development characteristic and rule can be uncovered. It will provide the base for the controlling disaster technology study of safety production in coal mine.

采场围岩变形破坏特征值是煤矿安全生产中一项重要参数，目前获得的破坏参数多为二维静态数值，其时空演化规律掌握对岩层控制及矿井水防治理论研究具有重要意义。课题以淮南矿区深部A组煤层开采条件为研究对象，采用分布式光纤和并行电法为技术基础，通过岩石实验、数值模拟、物理模拟及现场监测数据分析研究，揭示加载条件下不同岩石变形破坏应变场及地电场响应特征，建立岩石受力、裂隙发育状态及其物性参数间响应关系，确立破断判别阈值；构建A组煤层开采三维地质模型，研发单孔分布光纤及地电信息一体化采集装置，实时监测煤层开采采前、采中、采后围岩全时段裂隙演化信息，结合开采面顶、底板现场实测应变及地电信息数据，对开采过程围岩横向的超前支承应力、离层垮落、重复压实等分区，垂向的破断垮落、离层裂缝发育、弯曲变形等分带特征进行精细分析，重建围岩变形破坏三维时空演化过程，揭示其发育特征和规律，为井下安全生产控灾技术研究提供基础。

针对采场围岩变形破坏与地球物理场多参数响应关系及其时空演化特征这一关键科学问题，本项目以淮南矿区A组煤为基础开展相关工作，并拓展应用于西部鄂尔多斯盆地准格尔矿区深部煤层开采围岩变形破坏探测、监测研究。揭示了岩石破坏条件下地球物理多场多参数的响应特征，建立了加载条件下岩石变形破坏与应变场、地电场参数之间的相关关系，构建了岩石变形与破坏过程中地球物理多场多参数信息数据库；提出了井上、井下钻孔全断面光纤及电法综合测试系统，实现了煤层采前、采中和采后全过程围岩内部空间应变、地电等多源数据的实时获取，对开采过程围岩横向的超前支承应力、离层垮落、重复压实等分区，垂向的破断垮落、离层裂缝发育、弯曲变形等分带特征进行精细分析，揭示了围岩空间岩层破坏多场响应特征及精细发育规律；构建了基于多参数前兆信息对采动围岩的动态感知系统与精准评价模式。结合开采面顶、底板现场实测应变及地电信息数据，重建围岩变形破坏三维时空演化过程，揭示其发育特征和规律，为采场空间条件分析与岩层控制提供理论和实践基础。