Enhanced mechanical behavior of compacted clayey silts stabilized by reusing steel slag

Abstract

Finding new uses and applications of byproducts has significant importance due to the present need of minimizing the consumption of natural resources, reducing the amount of the disposal of waste materials and finding novel sustainable applications for these materials. This paper evaluates the behavior of compacted clayey loessical soils stabilized by the addition of steel slag (SS). Used soil is a loessical material made by quarts, feldspar and volcanic glass in different proportions. Different physical, microscopical and mechanical tests were performed in compacted specimens of clayey soil-SS mixtures. The influence of SS content, compaction moisture content and curing time on strength, deformation modulus, particle size, and pore structure were evaluated. The results showed increases in soil resistance and stiffness with the curing time, which can be attributed to the natural cementation that takes place due to interaction between the vitreous fraction of clayey silty particles and SS through pozzolanic reactions. This type of reaction is also confirmed by means of a direct measurement of a pozzolanicity index, evolution of pore sizes with a formation of more homogeneous microstructures and associated reduction in water content.