To study the influence of the alkaline activator on the performance of steel slag cement

the effects of alkaline activators (water glass、Na2CO3/NaOH、NaOH) on the macroscopic mechanical properties of steel slag cement are studied in this article. Further

the microscopic characteristic is investigated by hydration heat release

X-ray diffraction (XRD)

thermogravimetric analysis (DSC-TG)

scanning electron microscope (SEM) and mercury intrusion porosimetry test (MIP). The results show that the alkaline activators increased the basicity in the early hydration liquid phase of steel slag cement

accelerating depolymerization of steel slag vitreous to produce H3SiO-4 and H3AlO2-4

improving the reaction rate

facilitating the formation of C-S-H gel and zeolite products

which is manifested by the shortening of setting time and induction period

the increase of reaction heat

cumulative heat release and early mechanical strength; the influence of alkaline activators on the properties of steel slag cement is related to its molecular structure of activators

and the order of influence was water glass

Na2CO3/NaOH

NaOH in descending order; Water glass could increase the alkalinity of liquid phase in steel slag cement

and the SiO2-3 could react with Ca(OH)2 to produce C-S-H gel. The addition of alkaline activators can promote the hydration reaction of steel slag cement

which is helpful to the improvement of the mechanical properties and the compactness of the microstructure of steel slag cement.