基于PFC数值模拟的无底柱采场结构参数优化研究

Study on Stope Structure Parameter Optimization of Sublevel Caving without Sill Pillar Based on Numeral Simulation with PFC

结合大冶铁矿东采车间工程条件，设计了几种无底柱采场结构参数，并运用PFC数值模拟软件，对多个采场结构方案进行模拟分析，根据各方案的矿石回收指标和现场实施的难易程度，推荐采用分段高度12m、进路间距15m、崩矿步距2．0-2．5m的最优采场结构参数组合。同时研究了放矿过程中不同阶段颗粒间接触力的变化规律，详细分析了数值模拟结果回收率偏高和贫化率偏低的原因。

Based on the geological conditions in the east mining area of in Daye Iron Mine, several stoping schemes with different stope structure parameters for sublevel caving without sill pillar were designed, the several stoping schemes were simulated and analyzed by numeral simulation software PFC. According to the ore recovery indexes and the difficulty of field construction, the optimal one among candidate schemes was recommend, i. e. 12m sublevel height, 15m access space and 2.0 - 2.5m caving step space. Moreover, the changing rule of contact forces among particles in different stages during ore drawing was studied. The reasons why the ore recovery rate obtained from the numeral simulation is higher than actual one but the ore dilution rate obtained from the numeral simulation is lower than actual one were analyzed in detail.