Electrochemical Investigations of Steels in Seawater Sea Sand Concrete Environments

Xiang Yu; Saad Al-Saadi; Xiao-Ling Zhao; R K Singh Raman

doi:10.3390/ma14195713

Electrochemical Investigations of Steels in Seawater Sea Sand Concrete Environments

Materials (Basel). 2021 Sep 30;14(19):5713. doi: 10.3390/ma14195713.

Authors

Xiang Yu¹, Saad Al-Saadi², Xiao-Ling Zhao³, R K Singh Raman^{1

2}

Affiliations

¹ Department of Chemical Engineering, Monash University, Clayton, VIC 3800, Australia.
² Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC 3800, Australia.
³ School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW 2052, Australia.

Abstract

Seawater and sea sand concrete (SWSSC) is an environmentally friendly alternative to ordinary Portland cement concrete for civil construction. However, the detrimental effect of high chloride content of SWSSC on the corrosion resistance of steel reinforcement is a concern. This study undertook the electrochemical corrosion behaviour and surface characterizations of a mild steel and two stainless steels (AISI type 304 and 316) in various simulated concrete environments, including the alkaline + chloride environment (i.e., SWSSC). Open circuit potential (OCP), potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) were employed. Though chloride is detrimental to the corrosion resistance of mild steels, a simultaneous presence of high alkalinity in SWSSC negate the detrimental effect of chloride. In the case of stainless steels, a high level of alkalinity is found to be detrimental, whereas chloride seems to have less detrimental effect on their corrosion resistance.

Keywords: electrochemical impedance spectroscopy (EIS); open circuit potential (OCP); potentiodynamic polarization (PDP); seawater and sea sand concrete (SWSSC).

Grants and funding

DP160100739/Australian Research Council