尾砂膏体充填材料优化配比试验研究

Experimental Study on Optimization Ratio of Tailings Paste Backfill Material

为研究以尾砂为骨料、胶固粉为细集料的膏体充填材料基本物理力学特性和最优配比组合方式,采用室内材料成分分析、粒径筛分、沉降试验分别对尾砂、胶固粉的物理化学性质及流动性进行研究,并设计正交试验对不同质量浓度、不同粉砂比的尾砂膏体强度进行对比分析。试验结果表明：尾砂和胶固粉的主要化学成分相似,但含量不同,尾砂粒径大部分集中在0.1～1 mm之间,满足充填要求;随着质量浓度提高,沉降量减小,沉降时间亦缩短;当加入胶结料后,质量浓度为73%的浆液沉降值减小了3.5 mm,前10 min的沉降率为下降了14.14%;砂浆浓度一定时,充填体的强度与期龄呈正比关系,且随着粉砂比的增大,强度亦增加;粉砂比一定时,充填体强度与期龄呈正比关系,且随着料浆质量浓度的增大而增大;最优配比组合为粉砂比1∶5,质量浓度70%的充填体能满足强度要求。

Physical and chemical properties and mobility of tailings and solid plastic powder were researched by interior materials composition analysis,particle size screening and sedimentation test to study the basic physical and mechanical properties or the optimal ratio combinations of paste filling material with tailing as aggregate,plastic solid powder as fine aggregate. The paste strength of tailing with different concentrations and different ratios of silt were comparative analyzed by design orthogonal experiments. The results showed that the main chemical composition of tailings and solid plastic powder were similar,but the contents were different. The tailings diameters were mostly concentrated between 0. 1 mm and 1 mm,which meets the requirements of filling. The settlement amount is reduced and the settling time is also shortened with the mass concentration increased. The slurry settlement value of the mass concentration of73% decreased 3. 5 mm and the settling rate fell 14. 14% in first 10 min after adding binder. The positive correlation is between filling body and age when the mortar concentration is certain. The strength increased with the increased of silt ratio. The positive correlation is between filling body strength and age when the silt ratio is certain. The strength increased with the increased of mortar concentration.The silt is 1： 5 and the mass concentration is 70% is the optimal ratio,which meets the strength requirements