Effects of Gypsum and Vermicompost on Aggregate Stability of Bauxite against Liquefaction

Abstract

Abstract Improving stability and strengthening aggregate formation of bauxite in bulk cargoes to reduce the danger of liquefaction remains a challenge. The influence of gypsum and vermicompost on the alkali-aggregate reaction of bauxite against liquefaction in solid bulk cargoes are investigated using wet sieving, the modified Le Bissonnais' (LB), flow table, particle size distribution, specific gravity, scanning emission microscopy, and energy dispersive x-ray. Its effect on the aggregate stability of bauxite was investigated by including 2% and 4% gypsum and 4% and 10% vermicompost by weight of dry bauxite, respectively. The study of the soil samples suggested that the ideal condition for boosting aggregate stability and lowering the danger of bauxite liquefaction is at a level of 6% gypsum and 4% vermicompost, respectively. The addition of gypsum and vermicompost improves PSD at 2.5mm (20.38% increment), specific gravity (20.67% reduction), erosion resistance (40.00% increment), Mean Weight Diameter (75.51% increment), Transportable Moisture Limit (26.97% increment), and changes the microstructure of the bauxite from a sheet like structure to granular macro aggregated structure. The results shown that the addition of gypsum and vermicompost to bauxite had a direct effect on micromorphology and aggregate size distribution, resulting in an increase in aggregate stability and structure and a reduction in the risk of liquefaction.