Use of Corrosion Inhibitors for Steel Protection in Cementitious Composites-A Review

Abstract

Steel reinforced cementitious composite is one of the most commonly used materials in construction industries. This is mainly because of its excellent mechanical properties that can withstand various types of loading conditions and low cost. But, the corrosion of embedded steel reinforcement is a main problem associated with steel reinforced cementitious composite because it shortens the life of structure. The most important causes of corrosion initiation of steel reinforcement are the ingress of carbon dioxide and chloride ions to the surface of steel. Though, the corrosion initiation of embedded steel can be delayed using corrosion inhibitors. However, after starting of corrosion, the effectiveness of corrosion inhibitor was reported to be reduced significantly and propagation of corrosion becomes more rapidly. Generally, the negative effects of the corrosion inhibitors on properties of cementitious composite were reported to be negligible. Also, the information regarding the long-term performance of the corrosion inhibitors in actual practice are very limited. Various investigations reported several types of corrosion inhibitors in order to control the corrosion of steel that were also used in construction industries commercially. However, some of the corrosion inhibitors were found to be poisonous and harmful to the environment. Therefore, there is need for more research on the corrosion inhibitors in order to find out the suitable inhibitor with low cost and without side effects to the environment