Effect on Structure and Early Hydration Activity of Steel Slag Modified by Adjusting Materials and Temperature

The aim of this paper is to investigate effect on hydration activity of steel slag by modifying its mineralogical composition and structure incorporating electric arc furnace steel slag (EAFS) and fly ash (FA) into it at high temperature, and the process was simulated in laboratory that mineral admixtures were added to the melting slag during slag-discharging process. The mineralogical composition, microstructure of both basic oxygen steel slag (BOFS) and modified steel slag (MSS) were identified with XRD and optical microscopy. The results show that after modification, silicate minerals in MSS are decreased in amount with FA being increased; furthermore, silicate minerals in which are increased in amount with C/S molar ratio improvement. Three days cumulative hydration heat of GB40-1350 is greater than that of BOFS by 1.9 times.