【摘要】 为研究正断层煤层开挖煤岩体力学的特性,通过建立正断层附近煤层开挖时煤岩体的力学模型,运用FLAC3D数值计算并理论分析了上下盘开挖时煤岩体的力学特性。结果表明:水平位移、水平应力对煤层开挖顶端岩体的影响较小,地应力引起的竖向位移和开挖顶端相当应力是造成冒顶和开挖顶端岩体塌落的主要因素,当煤层中存在正断层时,从上盘开挖引起开挖顶端的相当应力和竖向位移比从下盘开挖引起的小,开挖区与断层距离越近,开挖顶端相当应力和竖向位移越大,相同条件下从上盘开挖较从下盘开挖更安全。因此,在工程实际中应尽量避免从下盘对煤层进行开挖,从而减小安全隐患。更多还原

【Abstract】 In order to study mechanical characteristics of coal and rock mass in coal seam excavation of normal fault, through establishing the mechanical model of coal and rock mass excavation in the vicinity of the normal fault, using FLAC3 Dnumerical calculation, we theoretically analyzed the coal and rock mass mechanical properties during excavation of upper and lower plates.The results show that horizontal displacement and horizontal stress have little effect on the excavation of the top rock mass of the coal seam. The vertical displacement caused by the ground stress and the considerable stress at the excavation top are the main factors causing collapse of the roof and the top of the excavated rock mass. When there is a normal fault, the considerable stress and vertical displacement caused by excavation from the upper plate is smaller than that caused by excavation from the lower plate. The closer the excavation area is to the fault, the greater the corresponding stress and vertical displacement at the top of excavation is. Under the same conditions, it is safer to excavate from the upper plate than from the lower plate. Therefore, in the actual project, the excavation of the coal seam from the lower plate should be avoided as far as possible so as to reduce the potential safety hazards.更多还原