Physical and Mechanical Properties of Foamed Mixture Lightweight Soil Doped With Bauxite Tailings Slurry

Abstract

In order to make better use of the BTs slurry with high water content stored in tailings ponds by wet method, foamed mixture lightweight soil (FMLSB) at four wet density were prepared using dry BTs and BTs slurry with different water contents. Their wet density, fluidity, unconfined compressive strength and water absorption were tested through indoor test, and the experimental results were analyzed by microstructure analysis. The results show that the performance of FMLSB improves as the wet density and water content of BTs slurry increase. FMLSB prepared by BTs slurry with 60% water content is poorly fluidity. That means at lower wet density due to the connected internal pores, its strength is significantly reduced and water absorption is significantly increased compared to the dry BTs group. However, with the increase of wet density, the above adverse effects of FMLSB caused by BTs slurry with low water content will decrease; and with the increase in water content of BTs slurry, its internal pore structure is significantly improved, the same as its unconfined compressive strength. When the water content is 100%, its performance is no different from that of dry BTs group. With the increase of wet density, the C-S-H produced by hydration reaction of FMLSB increases, forming a dense skeleton structure together with BTs particles and the unconfined compressive strength increases exponentially. The research results can provide a scientific basis for the direct utilization of high water content BTs slurry in tailings pond.