Abstract: Solid waste concrete was prepared using slag,steel slag,desulfurization gypsum cementing materials entirely replace cement clinker as binding material,influence of steel slag specific surface area and steel slag proportion on the comprehensive strength of the concrete was researched.The results showed that:increasing the specific surface area of steel slag,the compressive strength of concrete increases gradually.Steel slag powder on the early time comprehensive strength of concrete is less than that of slag powder.When the specific surface area of steel slag is 640 m2/kg,proportion of steel slag powder,slag powder,desulfurization gypsum accounted for 25%,63%,12% cementing materials respectively,the concrete compressive strength is the highest.Steel slag,slag and desulfurization gypsum interact with each other,promoting the formation and growth of ettringite and C-S-H gel; Ettringite formation is the main source of solid waste concrete early strength,in the late hydration reaction,ettringite and C-S-H gel intertwined and form a compact structure,which can increase the strength of the concrete with industrial solid wastes.

Key words: Steel slag, Blast furnace slag, Concrete, Hydration