综放开采断层活化突水渗流转换试验研究

Experimental study on the conversion from seepage to flow of water inrush aroused by fault activation in fully mechanized top-coal caving

为了揭示断层活化突水水量变化过程机理,在综放开采工作面断层突水实例分析的基础上进行了断层活化突水相似材料模拟,设计了在断层上盘下方开采和下盘下方开采时不同水压力作用下的断层活化突水的试验模型。根据试验所获得的数据分析了水流雷诺数、断层带充填物和断层带空隙度随时间的变化规律,并对比了空隙度和涌水量随时间的变化规律。根据分析结果得到综放开采断层活化突水经历了孔隙流—裂隙流—管道流过程,并根据试验得到的充填物涌出量随时间的变化规律判断孔隙流向裂隙流转换的时刻(7,9,13和15 s),根据空隙度随时间的变化规律判断裂隙流向管道流转换的时刻(30,35和40 s)。试验结果解释了综放开采断层活化突水渗流转换现象,与现场综放开采断层突水实例表现特征吻合。

In this paper, to reveal the water change process of water-inrush aroused by fault activation, based on the example analysis of water inrush through fault in the fully mechanized top-coal caving face, the similar material simulation models of water inrush aroused by fault activation under different water pressures were designed, including the coal mining under the hanging wall and foot wall of fault, re- spectively. Meanwhile, the variation rules of Reynolds numbers, fillings and voidage of fault zone along with time were analyzed according to the test data, and the variation rules of voidage and water inflow along with time were comparized. The results show that the water inrush aroused by fault activation in fully mechanized top-coal caving has experienced the process of pore fluid, fracture flow and pipe flow, and the time when the pore fluid converses into fracture flow （7, 9, 13 and 15 s） is identified according to the variation law of filling emission quantity along with time, while the time when the fracture flowconverses into pipe flow （30, 35 and 40 s）is obtained according to the change law of voidage along with time. The test results have explained the conversion phenomenon from seepage to flow of water inrush aroused by fault activation in fully mechanized top-coal caving, and are anastomotic with the expressive characteristics of field examples.