关键词: 铝土尾矿泥浆; 掺砂改良; 降雨蒸发作用; 抗剪强度;

Abstract: In view of the poor properties of bauxite tailings mud such as high water content, low permeability, high compressibility, high liquid limit and subjecting to dual influence from rainfall and evaporation in the storage process, the research on indoor sand-mixed improvement for bauxite tailings mud was carried out.The cracks, moisture absorption and shear strength of modified bauxite tailings mud of different particle sizes sand and sand mixing ratios were analyzed after evaporation and rainfall, and the optimal sand mixing parameters were determined by analyzing the improvement of the mud properties.The results showed that the change law of slurry evaporation of bauxite tailings mud and crack promoted each other.The slurry evaporation of bauxite tailings mud was larger in the medium sand group with sand ratio of 20%,and the crack developing degree was the highest.When the sand-mixed ratios were 0%～30%,the internal friction angle increased with the increase of sand ratio.In the range of 0%～20% sand-mixed ratio, the cohesion of sand-mixed bauxite tailings mud was obviously improved, while the cohesion of mud decreased when the sand ratio exceeded this value.It was concluded that the slurry improvement effect was the best when the sand particle diameter was 2.0～5.0 mm and the sand ratio was 20%.The research results provide parameter support for the engineering application of sand-mixed bauxite tailings mud.

Key words: bauxite tailings mud; sand-mixed improvement; rainfall evaporation action; shear strength;