不同浓度料浆流变特性与混合骨料级配相关性试验

为了探究混合骨料配比及粒径级配对料浆流变特性的影响，首先对矿山充填常用的废石和棒磨砂及其混合骨料进行粒径分析，并得到相应的特征粒径.其次采用流变仪对不同骨料配比、不同质量分数条件下的料浆进行测定，采用H-B流变模型拟合出相应的流变参数.然后对流变参数和流变特性进行分析，并基于最小二乘法研究骨料粒径级配与料浆流变特性的相关性.最后对料浆稳定性进行讨论，并通过建立力学模型确定了混合骨料不沉降离析的临界粒径范围为13.8~21.6mm.试验结果表明:料浆屈服应力和表观黏度均随料浆质量分数的增大而增大；随着剪切速率的增大，料浆流变特性表现出不同的模型特性；料浆流变特性参数与骨料粒径级配的相关性随着特征粒径值的增大而增大.随着质量分数的提高，料浆屈服应力与骨料粒径级配相关性逐渐减弱，而表观黏度与之相反，质量分数和骨料粒径级配对料浆稳定性有很大影响.

Experiment on Correlation Between Rheological Properties of Filling Slurry with Different Mass Concentration and Mixed Aggregate Gradation

In order to explore the effects of mixed aggregate ratio and particle size gradation on the rheological properties of the slurry，firstly， the particle size of the waste rock， rod mill sand and the mixture of them commonly used in filling was analyzed， and the corresponding characteristic particle size was obtained.Secondly， the slurry with different aggregate ratios and different mass concentrations was prepared by rheometer. The rheological parameters were fitted by H-B rheological model. Then，the rheological parameters and rheological properties were analyzed， and the correlation between aggregate size distribution and rheological properties of slurry was studied based on least square method.Finally， the stability of slurry is discussed， and the critical particle size range of non-settling segregation of aggregate is 13.8~21.6mm by establishing mechanical model. The test results show that the yield stress and apparent viscosity of the slurry increase with the increase of slurry mass concentration. The rheological properties of slurry show different model characteristics with the increase of shear rate. The correlation between rheological properties parameters of slurry and aggregate particle size distribution increases with the increase of characteristic particle size. With the increase of mass concentration， the correlation between slurry yield stress and aggregate size gradation gradually decreases， while apparent viscosity gradually increases. The mass concentration and aggregate size gradation have a great influence on slurry stability.