Cathodic protection is a technique by which use electrical potential of a steel increase it level at which corrosion cannot be take place it is widely used for both steel and concrete off shore structure while an land it has been used for protection of pipeline and similar structure.

Two different method employed on impression current and use of sacrificial anode. In the first the structure is connected to the negative terminal as a DC power source ideally using and anode which does not corrode. In the second reinforcement is connected to the anode with more negative corrosion potential than steel such as zinc or aluminum.

In this case electrical continuity of reinforcement is required. The principle of cathodic protection have been used to remove chloride for contaminated concrete.