Potential measurements are commonly used in corrosion surveys of steel reinforced concrete structures. The potential difference between the steel and a reference electrode, either placed on the concrete surflce or permanently embedded in the concrete, is indicative of the state of corrosion of the steel. However, the electrolytic nature of concrete gives rise to disturbing phenomena that might introduce errors in the potential readings. The error that is most problematic originates from liquid
junction potentials in the concrete. The origin and magnitude of junction potentials have been studied both theoretically and experimentally.
Keywords: Potential measurements, reference electrodes, liquid junction potentials, corrosion. concrete.