The effect of various environmental conditions on stabilization/solidification (S/S) of oil-contaminated soil using alkaline activation of granulated blast furnace slag (GBFS)

Abstract

Alkali-activated materials (AAMs) have been proposed as sustainable alternatives to traditional stabilizers. This study investigated the effect of freeze-thaw and wet-dry conditions on the durability of oil-contaminated soil stabilized using alkaline activation of granulated blast furnace slag (GBFS). The effect of curing temperature on GBFS-based samples was also evaluated. The main goal was to provide a suitable platform for the use of this eco-friendly material to improve the durability of oil-contaminated soil. Based on unconfined compressive strength (UCS) results and micro and macro investigations, the formation and melting of ice lenses increased the freezing and thawing cycles of the holes and, as a result, the UCS of the GBFS-based samples decreased. As the wet-dry cycle increased to 3, the UCS rose and then decreased. Raising the amount of GBFS and reducing the amount of crude oil in the GBFS-based samples prevented a sharp decrease in UCS and improved durability by increasing the entanglement and connection of particles and creating a denser structure. Increasing the curing temperature by removing free water and accelerating the geopolymerization and hydration reactions caused a further rise in UCS. In general, this study showed the appropriate circumstances for using this stabilization method for crude oil-contaminated soils in different environmental conditions.