关键词: 沟谷地形, 浅埋煤层, 上覆岩层, 采动裂缝, 岩层移动

Abstract: Abstract：In order to study the development law of overburden mining-induced fractures in shallow seam with thin bedrock under the condition of gully topography, this paper uses Shenfu mining area as the research base to analyze the development characteristics of overburden mining-induced fractures on 5-2 coal mining face of Anshan coal mine, and establishes the main roof stress model under the action of weak overburden, that is, the structure model of beam with non-uniform load. Based on the mechanical analysis of the beam structure with non-uniform load, the discriminant conditions of the stability of the bearing structure of the bedrock are derived, the calculation formulas of the parameters such as the pressure, shear force and the ultimate span of the main roof at both ends are determined, the influence law of the thickness and slope change of the weak strength overburden on the mining crack spacing is revealed. The practice shows that the distance between the mining-induced fractures determined by the non-uniformly distributed load beam model and the periodic weighting step are approximately the same; the mining-induced fractures in the overburden develop and evolve periodically with the failure and instability of the bedrock, collapse-type and step-type mining-induced fractures are more developed near the surface above the working face, and the surface fractures above the goaf gradually evolve into closed-type surface fractures with smaller displacements and openings.