Use of Alkali-Activated Fly Ashes for Soil Treatment

Abstract

The use of alkali-activated fly ashes (AAFA) to improve engineering properties of clayey soils is a novel solution, alternative to the widely diffused improvement based on the use of traditional binders such as lime and cement. An experimental investigation on chemo-physical evolution of alkali-activated binders and their use for soil improvement has been developed. Treated samples were prepared by mixing soil and fly ash with water and alkaline solution and dynamically compacted. Mechanical behaviour has been investigated by means of triaxial tests performed on treated samples compacted at optimum water content. Addition of alkali activated binder increased stiffness and shear strength of treated samples, whose extent depends on binder content and curing time.