Mechanical properties and microstructure evolution of alkali-activated GGBS-fly ash-steel slag ternary cements

Multi-component alkali-activated materials have excellent performance, solving the problem of poor performance in part of single-component alkali-activated materials. This study investigated the mechanical properties and microstructure evolution of alkali-activated GGBS-fly ash-steel slag ternary cement (ATC). Results showed that incorporating steel slag considerably increased the fluidity and prolonged the setting time of the alkaliactivated GGBS system, while the compressive strength only slightly decreased. Incorporating steel slag into the alkali-activated fly ash system effectively enhances the compressive strength of ATC. This is attributed to the C2S and C3S in steel slag participating in the formation of C-(N)-A-S-H gel products, improving the porosity and microstructure of ATC. Furthermore, ATC exhibits excellent compressive strength, pore structure, and microstructure compared to the alkali-activated GGBS-fly ash system, while also demonstrating similar properties to the alkali-activated GGBS-steel slag system.