CORROSION OF STEEL

The term corrosion is defined as an act or process of gradual wearing away of a metal due to chemical or electro-chemical reaction by its surroundings such that the metal is converted into an oxide, salt or some other compound. A substance known as rust results from such a process. In other words, the corrosion indicates the deterioration and loss of material due to chemical attack.

HOW TO PREVENT CORROSION OF STEEL IN CONCRETE?

The steel is the most liable to the corrosion and hence the study of steel corrosion is of paramount importance. To minimize the chances of development of corrosion of steel in concrete, the following preventive measures may be taken.

·         Avoiding heavily congested reinforcement especially at the intersection of beams and columns.

·         Avoiding the steel to come into contact with bricks, soil, wood and other porous non-alkaline materials

·         Avoiding the use of materials which accelerate the process of corrosion i.e. aggregates with high salt contents, water containing salts, etc.

·         Cleaning the reinforcement with wire-brush to remove the rust scales before placing of concrete

·         Maintaining a high degree of workmanship

·         Proper structural design with due provision of cover

·         Providing cathodic protection to the reinforcement by some suitable method

·         Providing surface coatings with paints, tars, asphalts, etc

·         Use of high quality and impermeable concrete

·         Using stone pebbles in place of badly made cover blocks

·         Using the correct water-cement ratio

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