Redistribution of corrosion products on steel bar/concrete interfaces in repaired concrete under influenced of aggressive ions

Abstract

Abstract The important cases contribute to deterioration of reinforced concrete structure were due to corrosion attack to the reinforcing steel bar. Instead of penetration of aggressive ions for example chlorides, sulphates, acids and others; the selection of materials used for repair should be concern as well. Due to this factor, the understanding on the electrochemical behavior of reinforcing steel bar using different materials for repairing for deteriorated concrete structures will be considered. To understand this phenomenon, the ready-cast specimens mixed with chloride as prepared earlier will be demolished at 301 days of concrete age. Surprisingly, potential measurement of reinforcing steel bars was reoriented to a lower corrosion risk at 301 days of concrete age. The chemical and microstructural factors related to corrosion products were quantitatively identified and correlated it using electrochemical measurements results. For corroding reinforcing steel bar by fully and partially influenced of chloride ions, the corrosion products were mainly contained wuestite, magnetite and lepidocrocite confirmed by XRD patterns. Depending on morphology and multi-elemental content, it shows that chloride ion is approaching the reinforcing steel bar that lead to greater corrosion rate in Reference specimen compared to repaired ones. However, the existence of Ca(OH) in the vicinity between concrete/reinforcing steel bar helps to prevent further corrosion attacks