Steel Corrosion In Recycled Aggregate Concrete Containing Amino Acid

Recycled aggregate concrete has been focused on due to the shortage of aggregates for concrete and the effective utilization of resources. So, this study experimentally investigated the possibility of the recycled aggregate reinforced concrete containing Arginine which would improve both the living environment for fishes in the sea and the resistance performance against chloride induced corrosion of steel in concrete. In this study, immersion test of reinforced concrete specimens into salt water and chemical analysis of pore solution extracted from mortar specimens by high compression were carried out.As a result, the protection performance against steel corrosion in the recycled concrete was not much improved by the dosage of Arginine. However, the combination of the admixture of Arginine and fly ash as the substitute of the fine aggregate was most effective to improve the resistance performance against chloride penetration into concrete and consequent steel corrosion in concrete. Moreover, it was confirmed that the concentration of hydroxide ions in pore solution increased while that of chloride ions decreased with the dosage of Arginine, which would result in the enhancement of the protection performance against steel corrosion in concrete.