关键词: 近距离煤层, 上行开采, 覆岩裂隙, 裂隙发育范围

Abstract: To study the safety and feasibility of up-mining near coal seam, taking the 7 and 8 coal seams of Baizhuang Coal Mine as the research object, by means of theoretical analysis, FLAC 3D numerical simulation, and engineering measurement, The development range of water-conducting fractures in overburden after mining in the lower 8 coal seam and the failure law of underburden rocks in different layers in the fracture zone are studied. The results show that the theoretical analysis and numerical simulation verify that the maximum height of mining caving zone and the average height of overburden fracture zone are less than the spacing of coal seam. According to the field measurement, the caving zone is within 7.3m from the vertical height of 8 coal. The vertical height is 7.3~14.4m and the water permeability is greater than 20 L/min. The vertical height is 14.4~21.2m, and the water permeability is 10~20L/min. The vertical height is 21.2~29.6m, and the water permeability is 5~10 L/min. The vertical height is 29.6m, which is a curved subsidence zone. The two coal seams are 31.6m apart, and the 7 coal seam is outside the 8 coal mining fracture zone, which is less than 5 L/min water leakage in the micro-crack zone, and the 7 coal seam integrity is less damaged. Therefore, it is safe and feasible to adopt upward mining in 7 and 8 coal seams. The research conclusion can provide reference for related up-mining of close coal seam.