【摘要】 为提高煤炭资源回采率、处置大量煤基固废，以面间煤柱掘充一体化为背景，考虑龄期对充填体强度及承载能力的影响，通过室内试验研究不同水泥含量下充填体强度随龄期变化的演化规律，发现水泥含量与充填体强度呈正相关关系，充填体强度随龄期呈指数函数增长趋势；基于弹性地基梁理论，建立“掘-充”过程中充填体-顶板协同承载力学模型，给出“掘-充”过程中各个区域的顶板挠度方程；利用FLAC^3D数值模拟探究“掘-充”过程中充填体水泥含量、掘充间距、掘充速度对充填体应力及顶板下沉量的影响，分析“掘-充”过程中不同掘进距离下充填体-顶板协同承载结构稳定性。结果表明：在面间煤柱“掘-充”过程中，水泥含量越高、掘充间距越小则充填体强度形成时间越快、顶板下沉量越少；掘充速度越快则充填区内充填体龄期越短、强度越低、承载效果越差、顶板塑性区破坏越严重；随着掘进距离的推进，充填体承载能力逐渐增强，顶板下沉速度逐渐减小，充填体-顶板协同承载结构逐渐趋于稳定。更多还原

【Abstract】 In order to improve the recovery rate of coal resources and dispose of a large amount of coal-based solid waste, based on the integration of excavation and filling of inter-face coal pillars, considering the influence of age on the strength and bearing capacity of the backfill body, the evolution law of the strength of the backfill body with age under different cement contents was studied through laboratory tests. It was found that the cement content was positively correlated with the strength of the backfill body, and the strength of the backfill body increased exponentially with age. Based on the theory of elastic foundation beam, the cooperative bearing capacity model of backfill body-roof in the process of excavation-filling was established, and the roof deflection equation of each region in the process of excavation-filling was given. FLAC^3D numerical simulation was used to explore the influence of backfill body cement content, excavation-filling distance and excavation-filling speed on backfill body stress and roof subsidence in the process of excavation-filling, and the stability of backfill body-roof cooperative bearing structure under different excavation distances in the process of excavation-filling was analyzed. The results show that in the process of excavation-filling of inter-face coal pillars, the higher the cement content and the smaller the excavation-filling spacing, the faster the strength formation time of the backfill body and the less the roof subsidence. The faster the excavation and filling speed, the shorter the age of the backfill body in the filling area, the lower the strength, the worse the bearing effect, and the more serious the damage of the plastic zone of the roof. With the advancement of the excavation distance, the bearing capacity of the backfill body gradually increases, the roof subsidence rate gradually decreases, and the backfill body-roof cooperative bearing structure gradually stablizes.更多还原