渭北保水采煤区软岩底板隔水岩层组稳定性控制机理研究

Weibei Permo-Carboniferous coal reserves of rich, easy to induce protective adverse Yellow River wetland ecological deterioration, its roots lie in the floor impermeable layer instability caused damage to break the balance of groundwater in karst water system loss, especially on the 10th coal seam floor water retention areas, reasonable to optimize key technical parameters Ordovician limestone reinforcement layer is the fundamental way. Currently, for the No. 5 Seam Floor Weibei structure theory has done more in-depth study, for the 10th floor watertight seams less soft rock stability studies, study the overall stability of the soft rock group impermeable rock bottom yet is blank, revealing impermeable rock group stability to grouting Ordovician limestone layer as a guide water impermeable layer of rock fractured group, established soft rock bottom impermeable rock group key technical parameters determination method is the "water retention mining" to carry out the scientific basis for the theory in practice Weibei mine has important significance and economic value. Task Force to Weibei on the 10th floor of soft rock seam coal mining under water as the background, strong research grouting Ordovician limestone aquifer transformed into a water-impermeable layer implementation of mining proposed impermeable rock group "mined crack" and "water guide fissure" development law, establish the overall stability of the mechanical model impermeable rock group and determine the basis for the protection of karst Oizumi Weibei normal traffic and industrial and agricultural water security and provide scientific basis.

我国渭北石炭二叠纪煤炭储量丰富，保护不利易诱发黄河湿地生态环境恶化，其根源在于底板隔水层失稳破坏打破岩溶水系平衡引起地下水流失，特别是10号煤层底板保水采煤区，合理优化奥灰加固层关键技术参数是根本途径。目前，针对渭北5号煤层底板结构理论做过较为深入的研究，对于10号煤层软岩底板隔水稳定性的研究较少，对于软岩底板隔水岩层组隔水整体稳定性的研究尚属空白，揭示隔水岩层组稳定性，以注浆加固奥陶纪灰岩层作为隔水岩层组的导水裂隙发育层，建立软岩底板隔水岩层组关键性技术参数确定方法，是“保水采煤”理论在渭北矿区开展实践的科学基础，具有重要意义和经济价值。课题组以渭北10号煤层软岩底板保水采煤为背景，研究注浆加固奥灰强含水层改造成隔水层实施保水采煤，提出隔水岩层组“采动裂隙”和“导水裂隙”发育规律，建立隔水岩层组整体稳定性力学模型及判别依据，为保护渭北地区岩溶大泉正常流量和工农业用水安全提供科学依据。

我国渭北石炭二叠纪煤炭储量丰富，保护不利易诱发黄河湿地生态环境恶化，其根源在于底板隔水层失稳破坏打破岩溶水系平衡引起地下水流失，特别是10号煤层底板保水采煤区，合理优化奥灰加固层关键技术参数是根本途径。目前，针对渭北5号煤层底板结构理论做过较为深入的研究，对于10号煤层软岩底板隔水稳定性的研究较少，对于软岩底板隔水岩层组隔水整体稳定性的研究尚属空白，揭示隔水岩层组稳定性，以注浆加固奥陶纪灰岩层作为隔水岩层组的导水裂隙发育层，建立软岩底板隔水岩层组关键性技术参数确定方法，是“保水采煤”理论在渭北矿区开展实践的科学基础，具有重要意义和经济价值。.本课题采用理论分析、数值模拟、物理模拟、实验室试验等方法对软岩底板隔水层稳定性的若干难点和热点问题展开较深入的研究。.（1）分析了渭北煤田10号煤层保水采煤区软岩底板隔水层与奥灰加固层结构组合特征，确定了隔水岩层组的特征及分类。.（2）采用电液三轴伺服仪研究了煤岩体的应力-应变全过程曲线特征和渗流规律。.（3）建立了软岩底板隔水岩层组“软岩隔水层-有效隔水层-奥灰加固层”力学模型，推导得出了采动裂隙发育深度和导水裂隙发育高度的计算表达式，并结合软岩底板隔水岩层组整体稳定性判断依据给出了最小隔水层厚度理论解析解。.（4）采用数值计算与物理模拟相结合的方法，开展针对性的实验研究。采用数值模拟解决了应力场、应变场和渗流场与裂隙发育之间的相互关系，揭示了其裂隙发育规律及形成机理；物理模拟着重解决了隔水岩层宏观裂隙发育规律及其隔水岩层位移场演化规律。.（5）在现场开采了煤体支承压力和底板采动破坏规律现场实测，并将其结果与理论和模拟计算结果相互对比分析，验证和完善了本课题的研究成果。.课题组以渭北10号煤层软岩底板保水采煤为背景，所建立的隔水岩层组整体稳定性力学模型及判别依据，可为保护渭北地区岩溶大泉正常流量和工农业用水安全提供科学依据。