下向进路充填采矿法人工假顶强度及配筋参数研究

构筑人工假顶是下向进路充填安全高效采矿的关键和前提，人工假顶充填体强度与配筋参数相互关联，直接决定着回采作业的安全性与经济性。通过建立顶板多层充填体普氏平衡拱模型，优化下向进路充填假顶所受荷载的计算方法；应用薄板理论及弹性力学理论并结合下向进路充填采矿工艺，解析充填体假顶强度要求；将钢筋混凝土结构设计方法应用于下向进路充填假顶配筋率计算，形成下向充填采矿人工假顶强度及配筋率的整体方案。以某金银矿山大结构参数（5 m×5 m）回采进路为例，提出假顶厚2 m，充填体强度不小于5 MPa，Φ12 mm钢筋（HRB335）网度300 mm×300 mm，配筋率0.106%的技术要求，对合理构筑人工假顶和安全高效应用下向进路充填采矿法具有指导意义。

Study on the Strength and Reinforcement Ratio of the Artificial Roof of Underhand Drift Cut-and-fill Stoping

Constructing the artificial roof is the key and precondition of safe and efficient cut-and-fill mining in underhand drift stoping.Filling strength and reinforcement ratio of the artificial roof are correlative and related to the safety and economics of ore extraction directly.The method of computing the bearing load of the artificial roof is optimized by constructing a multi-layered pressure-arch model.Based on thin plate theory,elastic mechanics theory and the mining technology of underhand drift cut-and-fill stoping,the strength of the backfilling artificial roof is resolved.The design method of reinforced concrete structure is applied to compute the reinforcement ratio of the bearing layer of underhand drift cut-and-fill stoping.The whole scheme design of the artificial roof's strength and reinforcement ratio is presented,and for one gold-silver mine that applied large structural parameter (5 m×5 m),the strength and reinforcement ratio are determined.The thickness of the artificial roof is 2 m,the strength is no less than5 Mpa,bar-mat reinforcement (12mm HRB335) is 300 mm×300 mm,the ratio of reinforcement is 0.106%.The research is instructive and meaningful to constructing the artificial roof and applying underhand drift cut-and-fill mining method safely and efficiently.