Deep Decarbonization of UHPC Using Carbonated Steel Slag

Electric arc furnace (EAF) slag was carbonated using an aqueous solution approach with a liquid-to-solid mass ratio of 10:1, under an environment of 99.9% purity CO2 and 2 bar pressure. The carbonated EAF was used to partially replace cement to develop low-carbon ultra-high performance concrete (UHPC) binder. The compressive strength of UHPC binder was marginally reduced by less than 5% up to a substitution level of 50%, after which a significant reduction of 23.68% was observed.