A study on the relationship of water/cement ratio with the corrosion of steel reinforcement in concrete

This paper deals with the investigation of the effect of variation of water/cement ratio on the ability of the concrete to protect steel reinforcement against corrosion. Forty samples were reinforced with steel, while the remaining eight samples which were used for porosity test were plain concrete blocks. The water-cement ratio used for the samples ranged from 0.35 to 0.70.The reinforced samples were exposed to 3 NaCI solution to promote corrosion.To determine the existence of corrosion in the samples, potential measurements of the steel reinforcements were done using a Cu-CuSO half-cell electrode.Assessment of the degree of corrosion was done by the use of the criteria set by ASTM D876-80.To confirm the results obtained through electrochemical potential measurements, the concrete cover of the samples were cracked upon to expose the steel reinforcements.Based on the findings of the study, it was found that the lower the water/cement ratio, the less protective the concrete cover is against corrosion and the higher the water-cement ratio, the more protective against corrosion is the concrete cover for steel reinforcements