Abstract:
Chloride is not the only main cause of corrosion of reinforced concrete structures in
seawater environment. Microorganisms, such as bacteria and microalgae, in the seawater can induce
microbiologically influenced corrosion (MIC) that leads to degradation of the concrete structures by
formation of biofilm on the metallic surface. In this preliminary study, the impact of microalgae on
the corrosion of steel reinforced bars in fly ash geopolymer concrete was studied. Corrosion
potential, algae cells number, and pH measurement were carried out for fly ash geopolymer
concrete and a control mix (Ordinary Portland Cement) samples. The results indicate that the
corrosion potential of fly ash geopolymer concrete was influenced by the cathodic reaction during
photosynthesis activities. The geopolymer concrete in algae-inoculated medium was found to be
more tolerant to algal growth than the control mix (OPC concrete). There was a positive correlation
between algae cell densities and the potential reading of the geopolymer
