为解决超细尾砂胶结充填材料(CUTB)流动性差、强度低的问题,分析了减水剂(SP)对CUTB的浆体流变、固化强度及波速等的改善效果,并提出了基于絮凝体含水量的屈服应力预测模型.结果表明:① 当SP 掺量从 0增加到 0.04%时,屈服应力和等效塑性黏度分别降低了 51.3%和 37.5%;② 提出的考虑絮凝体含水量的动态屈服应力模型是科学有效的,最大堆积密度和有效固体浓度是影响新拌CUTB屈服应力的主要微观因素;③ SP能够显著提高CUTB的强度,当SP掺量从0 增加到0.04%时,3、7、28 d强度分别提高了17.7%,34.0%和28.0%;④ 最优的SP掺量为 0.03%.研究结果可为矿山实际利用SP改善CUTB性能提供参考.
In order to solve the problem of poor flow and low strength of cemented ultra-fine tailings backfill(CUTB),this paper investigated the improvement effect of superplasticizer(SP)on the properties of CUTB such as rheology,strength and ultrasonic pulse velocity,and proposed a prediction model of yield stress based on the water content of flocculant.The re-sults show that:① The yield stress and equivalent plastic viscosity decreased by 51.3%and 37.5%,respectively,when the SP content increased from 0 to 0.04%.② The proposed dynamic yield stress model considering the water content of floc is scien-tifically valid,and the maximum packing density and effective solids concentration are the main fine-scale factors affecting the yield stress of fresh CUTB.③ SP can significantly improve the strength of CUTB.When the SP content was increased from 0 to 0.04%,the 3,7,28 dstrengths were increased by 17.7%,34.0%and 28.0%,respectively.④ The optimal SP content was 0.03%.The results of this paper provide a reference for the actual use of SP to improve the performance of CUTB in mines.