Biomineralization and corrosion inhibition of steel in simulated bio-inspired self-healing concrete

The concrete possessing quasi brittle nature is always prone to the transport of aggressive ions leading to corrosion of embedded steel. The use of bacteria-based self-healing concrete has been tremendously practiced since the last decade to repair such blemishes of concrete. In this research, interaction of 2 gram positive Chryseomicrobiam species with the simulated concrete and reinforcing steel has been studied in the chloride's environment. The effect of chlorides and varying pH conditions on the microbially induced CaCO3 precipitation (MICP) capability was explored along with the forensic investigations of the precipitates. The biofilm formation potential and electrochemical measurements were done to assess the corrosion inhibition tendency of steel bars by bacteria. The MICP potential of Chryseomicrobiam amylolyticum (CA) was high at each pH compared to the Chryseomicrobiam imtechense (CI). However, both of the strains produced vaterite and maximum amount was observed at a pH of 10. The CI strain formed denser and 42.27 % thicker biofilm compared to the CA. The corrosion inhibition efficiency of the rebars by CA and CI was 6.62 % and 90.42 % more than the control sample, respectively.