减水剂类型对细尾砂充填料浆流动性及强度的影响

采用聚羧酸、三聚氰胺以及萘系三种类型的减水剂,开展了减水剂在不同掺量下细尾砂充填料浆流动度、流变及强度试验,研究了减水剂类型和掺量对充填料浆流动度、屈服应力、塑性粘度、表观粘度、触变性及充填体强度的影响规律。研究表明:减水剂的掺入可以显著提高料浆流动度,降低屈服应力和表观粘度。减水剂对料浆塑性粘度的影响相对较小。此外,料浆触变性随减水剂掺量的增加呈现出先增强后减弱的变化趋势。相比三聚氰胺、萘系减水剂,聚羧酸减水剂对料浆流动性能的改善效果更优。一定充填浓度下,减水剂的掺入会降低充填体早期强度,但对充填体中后期强度影响较小,甚至略有提高。

Effect of Different Water Reducers on Fluidity and Strength of Fine Tailings Filling Slurry

Three types of water reducers, namely polycarboxylate superplasticizer, melamine superplasticizer, and naphthalene superplasticizer, were used in this study to test the fluidity, rheology, and strength of backfill at the different dosages of water reducer. The effects of water reducer type and dosage on the fluidity, yield stress, plastic viscosity, apparent viscosity, thixotropy, and strength of the backfill were studied. Research shows that adding a water reducer can significantly improve slurry"s fluidity, reducing yield stress and apparent viscosity. The effect of water reducer on the plastic viscosity of slurry is relatively small. In addition, the thixotropy of slurry increases first and then decreases with the increase of water reducer content. Compared with melamine superplasticizer and naphthalene superplasticizer, polycarboxylate superplasticizer has a more noticeable improvement effect on slurry flowability. At a certain concentration, adding a water reducer will reduce the early strength of the backfill, but it has a small impact on the strength of the backfill in the middle and later stages, even slightly increased.