【摘要】 为研究无底柱分段崩落法中多进路出矿截止品位对矿石贫化损失的影响特征，采用物理试验与PFC^3D数值模拟相结合的方法，以四川某钒钛磁铁矿为工程背景，开展了放矿物理模型试验，并构建了多进路放矿数值计算模型，探究多进路出矿模式下不同截止品位对出矿贫损指标的影响规律。结果表明：截止品位对贫损指标具有显著的影响，截止品位每增高1%，矿石回收率降低5.38%，废石混入率降低6.88%，贫化率降低4.29%，采出品位升高1.74%。通过多目标优化分析，确定该矿山的最佳截止品位为18%，可有效提升矿山的综合效益。研究成果为矿山生产实际中的放矿管理提供了理论依据。更多还原

【Abstract】 This study examines the impact of cut-off grade characteristics on ore dilution and loss performance in multi-drift ore drawing under sublevel caving without a sill pillar, a prevalent mining technique for underground metal deposits in China. Utilizing a combination of physical model tests and PFC^3D threedimensional numerical simulations, the research is anchored in the context of a substantial vanadium-titanium magnetite mine in Sichuan Province. We conducted specific physical model tests for ore drawing, developed a robust numerical calculation model for multi-drift ore drawing, and investigated the influence mechanisms of varying cut-off grades on ore dilution and loss indices within the multi-drift ore drawing production framework. The results from both the tests and simulations indicate that the cut-off grade exerts a highly significant controlling effect on the indices of ore dilution and loss. For each 1% increment in the cut-off grade, there is a corresponding decrease of 5.38% in ore recovery rate, a 6.88% reduction in the waste rock mixing rate, and a 4.29% decrease in ore dilution rate. Conversely, the run-of-mine grade exhibits an opposite trend, increasing by 1.74%. Through multi-objective optimization analysis based on empirical testing and simulation data, an optimal cut-off grade of 18% has been identified for the mine under study. This determination is anticipated to significantly enhance the comprehensive economic benefits of the mine’s routine underground operations. The findings of this research elucidate the relationship between dilution and loss indices and variations in cut-off grade, thereby providing a robust theoretical foundation for the scientific management of ore extraction.更多还原