(1. 北京科技大學 土木與資源工程學院，北京 100083；
2. 金屬礦山高效開采與安全教育部重點實驗室，北京 100083)
摘 要: 為了研究混合骨料膠結(jié)充填體強度特性及與開挖礦體的合理匹配，采用單因子多水平試驗設計方法對混合骨料膠結(jié)充填體進行配比試驗研究，探討質(zhì)量濃度、廢石摻量對混合骨料充填漿料坍落度及固化強度的影響，建立固化強度增長模型，借助SEM微觀測試手段研究了廢石摻量對混合骨料膠結(jié)充填體微觀結(jié)構(gòu)性能的影響。結(jié)合能量耗散原理，引入能量匹配系數(shù)K分析充填體與開挖礦體的合理匹配并定量分析了混合骨料膠結(jié)充填體作為人工假頂在采場內(nèi)的合理固化時間。結(jié)果表明：充填漿料坍落度隨質(zhì)量濃度增加呈線性遞減規(guī)律，隨廢石摻量增加呈指數(shù)函數(shù)增長規(guī)律；在養(yǎng)護齡期56 d內(nèi)，不同質(zhì)量濃度、廢石摻量的混合骨料膠結(jié)充填體固化強度遵循指數(shù)函數(shù)增長規(guī)律。微觀結(jié)構(gòu)分析表明，廢石摻量能夠?qū)Τ涮铙w內(nèi)部微觀結(jié)構(gòu)的致密性造成顯著性影響，進而影響充填體的宏觀機械強度；引入能量匹配系數(shù)K定量表征了充填體與開挖礦體之間的能量關系，得到了不同配比參數(shù)下的混合骨料膠結(jié)充填體在采場內(nèi)的固化時間變化規(guī)律；基于充填漿料坍落度、固化強度和固化時間等指標優(yōu)選出一組最佳的配比參數(shù)，即水泥摻量為310 kg/m3，質(zhì)量濃度為76%，廢石摻量為60%。
關鍵字: 充填體；能量匹配分析；固化時間；強度增長規(guī)律；坍落度；微觀結(jié)構(gòu)
（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
