The study of corrosion resistance of reinforcement steel embedded in concrete composed of commercial Portland cement and final tin slag against chloride environment

Abstract

Final tin slag is a by-product of slag-1 smelting process that contains oxides similar to the oxides in Portland cement (OPC), which are SiO2, CaO, Al2O3, and Fe2O3. Therefore, tin slag may be utilized as partial substitute for concrete raw material. The aim of this research is to understand the characteristics of OPC and the slag-2 cement mixture against corrosiveness of the cement and steel material as analysed using the cyclic polarization method. This study uses final tin slag from Bangka Island in Indonesia mixed with OPC of 10%, 20%, and 30% respectively. The molded concrete has a ratio of 0.5 w/c with 28 days curing process and then it is immersed in a 3.5% NaCl solution for 6days. The result shows that the steel in the 20% slag-2 concrete mixture has the most competitive and stable corrosion resistance compared to original OPC concrete, followed by 10%, and 30% slag mixture respectively.