Corrosion behavior of steel bars immersed in simulated pore solutions of alkali-activated slag mortar

To study the corrosion behavior of steel bars in alkali-activated slag (AAS) system, simulated pore solutions of AAS mortar were first applied in this work. The effects of the three major species in AAS pore solutions, namely sulfur-containing species, aluminate, and silicate, were investigated. Electrochemical impedance spectroscopy and potentiodynamic polarization results showed that the simulated pore solution of AAS mortar had a stronger capacity to passivate and protect steel bars than the simulated pore solution of Portland cement (PC) mortar, mainly due to the higher concentration of silicate in the former, as confirmed by surface analysis of SEM-EDXS.