Half Cell Potentiometer

It is used to determine the probability of corrosion within the rebar in reinforced concrete structures.

The method of half-cell potential measurements normally involves measuring the potential of an embedded reinforcing bar relative to a reference half-cell placed on the concrete surface. The half-cell is usually a copper/copper sulphate or silver/silver chloride cell, but other combinations are used.

Corrosion being an electrochemical phenomenon, the electrode potential of steel wire with reference to standard electrode undergoes changes depending on corrosion activity.