近距离煤层开采导水裂隙带发育高度数值模拟研究

为解决邵寨煤矿2号、5号煤层重复采动面临的覆岩破断及两带发育高度问题，以及研究此情形下导水裂隙带演化规律，运用数值模拟计算方法，采用3DEC数值模拟软件，通过对近距离煤层条件下工作面的回采进行模拟实验，获得导水裂隙带的演化趋势，以及工作面回采结束后的两带最终发育高度。模拟结果表明，导水裂隙带高度沿工作面倾向是从零开始逐渐增加的，最终当工作面回采360 m时，导水裂隙带高度增加至100 m,而走向导水裂隙带初始为煤2层采动造成的高度为78 m,随着煤5层的回采导水裂隙带高度保持不变，当工作面回采至220～260 m时向上延伸至100 m,随后继续保持稳定，导水裂隙带最终发育高度为100 m,贯穿了延安组岩层达到安定组岩层但并未到达洛河组含水层，可以保障井下的安全生产。

Numerical simulation study on development height of water fracture zone in close coal seam mining

In order to solve the problems of overlying rock fracture and the development height of the two zones faced by repeated mining in the 2nd and 5th coal seams of Shaozhai Coal Mine，as well as to study the evolution law of the water conducting fracture zone under this situation.This paper uses numerical simulation method，the use of 3DEC numerical simulation software，based on the condition of close distance coal seam mining working face in simulated experiment，obtains the evolution trend of the water transmitting fissure zone，and the final development height of the two zones after the mining of the working face.According to the simulation results，the height of the water conducting fracture zone gradually increases from zero along the dip of the working face.Finally，when the working face recovers 360 m，the water conducting fracture zone increases to 100 m，and the initial height of the water conducting fracture zone towards the strike is 78 m caused by the mining of coal layer 2.As the mining of coal layer 5 continues，the height of the water conducting fracture zone remains unchanged.When the working face recovers between 220 m and 260 m，it extends upwards to 100 m，and then continues to remain stable.Under the conditions of close coal seam mining in Shaozhai Coal Mine，the final development height of the water conducting fracture zone is 100 m，which runs through the Yan’an Formation rock layer and reaches the Anding Formation rock layer，but does not reach the Luohe Formation aquifer，which can ensure safe production underground.