(1. 北京科技大学 土木与资源工程学院，北京 100083；
2. 金属矿山高效开采与安全教育部重点实验室，北京 100083)
摘 要: 为了研究混合骨料胶结充填体强度特性及与开挖矿体的合理匹配，采用单因子多水平试验设计方法对混合骨料胶结充填体进行配比试验研究，探讨质量浓度、废石掺量对混合骨料充填浆料坍落度及固化强度的影响，建立固化强度增长模型，借助SEM微观测试手段研究了废石掺量对混合骨料胶结充填体微观结构性能的影响。结合能量耗散原理，引入能量匹配系数K分析充填体与开挖矿体的合理匹配并定量分析了混合骨料胶结充填体作为人工假顶在采场内的合理固化时间。结果表明：充填浆料坍落度随质量浓度增加呈线性递减规律，随废石掺量增加呈指数函数增长规律；在养护龄期56 d内，不同质量浓度、废石掺量的混合骨料胶结充填体固化强度遵循指数函数增长规律。微观结构分析表明，废石掺量能够对充填体内部微观结构的致密性造成显著性影响，进而影响充填体的宏观机械强度；引入能量匹配系数K定量表征了充填体与开挖矿体之间的能量关系，得到了不同配比参数下的混合骨料胶结充填体在采场内的固化时间变化规律；基于充填浆料坍落度、固化强度和固化时间等指标优选出一组最佳的配比参数，即水泥掺量为310 kg/m3，质量浓度为76%，废石掺量为60%。
关键字: 充填体；能量匹配分析；固化时间；强度增长规律；坍落度；微观结构
（1. School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. Key Laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education, Beijing 100083, China）
Abstract:In order to study the strength characteristics of mixed aggregate cemented backfill and the reasonable matching with excavated ore bodies, a single factor multi-level experimental design method was used to study the mixing ratio of mixed aggregate cemented backfill. The effects of mass concentration and waste rock content on the slump and solidification strength of mixed aggregate filler were discussed, the solidification strength growth model was established and the effect of waste rock content on the microstructure and properties of mixed aggregate cemented backfill was studied by SEM. Combined with the energy dissipation principle, the energy matching coefficient K was introduced to analyze the reasonable matching between the filling body and the excavated ore body, and the reasonable curing time of the mixed aggregate cemented backfill as the artificial false roof in the stope was quantitatively analyzed. The results show that the slump of filling slurry decreases linearly with the increase of mass concentration, and increases exponentially with the increase of waste rock content. Within 56 d of curing age, the compressive strength of the composite aggregate cemented backfill under different mass concentrations and waste rock contents follows the exponential function growth law. The microscopic test results show that the range of waste rock content can significantly affect the compactness of the microstructure inside the backfilling, which in turn affects the macroscopic mechanical strength of the backfilling. The energy matching coefficient K was introduced to quantitatively characterize the energy relationship between the filling body and the excavated ore body. The variation of the curing time of the mixed aggregate cemented backfill in the stope was obtained under different ratio parameters. Based on the parameters such as filling slump, curing strength and curing time, a set of optimal ratio parameters is selected: the cement content is 310 kg/m3, the mass concentration is 76%, and the waste rock content is 60%.
Key words: filling body; energy matching analysis; curing time; strength growth law; slump; microstructure
