word War Defined as the action or process of gradually removing a metal due to chemical or electrochemical Reacts with its surroundings in such a way that the metal is converted into oxide, salt or some other compound. a substance that is referred to as War result of such a process. In other words, corrosion indicates deterioration and loss of material due to chemical attack.

Concrete provides an ideal protective environment to protect steel from corrosion. Due to the high initial alkalinity, an extremely thin inert film of ferric-oxide (Fe2hey3) is formed automatically on the surface of the steel. This layer, although extremely thin, effectively protects the steel from corrosion. But unfortunately this layer remains effective as long as the surrounding environment remains alkaline. Therefore, if we can manage to keep the environment alkaline, the corrosion of steel can be effectively prevented and the durability of the structure can be ensured. The alkaline medium can be maintained for a longer period of time by making the concrete impermeable.

steel corrosion in concrete
steel corrosion in concrete

rust is a electrochemical process In which one part of the steel becomes the anode and the other becomes the cathode. Fortunately, the anode reaction cannot begin until the inactive ferric-oxide film is destroyed by the acidic medium or is made permeable by the action of chloride ions. Similarly the cathode reaction cannot begin unless sufficient oxygen and water are available on the surface of the steel. Therefore, it can be concluded that corrosion of steel can be prevented if the concrete is sufficiently impermeable so as to keep air, water and other such agents out of its reach.

Steel is most susceptible to corrosion and therefore the study of steel corrosion is of paramount importance. To reduce the chances of steel corrosion in concrete, the following preventive measures can be taken.

  1. Avoiding heavily congested reinforcement, especially at the intersection of beams and columns.
  2. Protecting steel from contact with bricks, clay, wood and other porous non-alkaline materials
  3. Avoiding the use of materials that accelerate the process of corrosion i.e. aggregates with high salt content, water containing salts etc.
  4. cleaning the reinforcement with a wire-brush to remove rust scales before placing the concrete
  5. maintaining a high standard of workmanship
  6. Proper structural design with proper provision of cover
  7. To provide cathodic protection to the reinforcement by some suitable method
  8. Providing surface coating with paint, tar, asphalt, etc.
  9. Use of high quality and impervious concrete
  10. Using stone pebbles in place of badly made cover blocks
  11. Using the right water-cement ratio

Er. Mukesh Kumar

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Er. Mukesh Kumar is Editor in Chief and Co-Funder at Civil Engineering Website. Mukesh Kumar is a Bachelor in Civil Engineering From MIT. He has work experience in Highway Construction, Bridge Construction, Railway Steel Girder work, Under box culvert construction, Retaining wall construction. He was a lecturer in a Engineering college for more than 6 years.