不同粒径尾砂料浆塌落度和屈服应力关系

Relation between slump and yield stress of tailing slurry with different particle sizes

尾砂料浆的流变特性既是水砂充填管道输送设计的重要指标,也可为尾砂胶结料浆的流动特性评价提供参考。基于标准塌落筒试验和流变试验,获得了不同质量浓度下4种尾砂料浆的塌落度和剪切屈服应力。结果表明:在料浆塌落度变化较大的质量浓度区间内,粗、细粒径尾砂料浆的塌落度均随料浆质量浓度的增加而减小,但细粒径尾砂料浆塌落度减小速度更快;随着质量浓度的增加,细粒径尾砂料浆的剪切屈服应力呈指数形式增大,而粗粒径尾砂料浆的屈服应力的变化相对不显著。通过分析粗、细尾砂料浆的塌落度和流变试验结果,发现料浆塌落度与屈服应力之间呈指数关系。

The rheological properties of the tailings slurry are not only an important indicator for the design of hydraulic backfill pipeline transportation,but provide a reference for the evaluation of the flow characteristics of the tailings cementitious slurry.Based on the standard slump test and rheological test,this study obtains the slump and shear yield stress of four type of slurries at different mass concentration.In the mass fraction range where the slump changes greatly,both the slump of coarse-grained tailings slurry and fine-grained tailings slurry decrease with the increase of mass fraction,but the slump of the fine particle tailings slurry decreases faster.With the increase of mass fraction,the shear yield stress of fine-grained tailings slurry increases exponentially,whereas the change in yield stress of coarse-grained tailings slurry is relatively insignificant.The analysis of the slump and rheological test results of coarse and fine sand slurry show that there is an exponential relation between the slump and the yield stress.