HALF-CELL POTENTIAL

Half Cell Potential testing is an effective and reliable method of assessing invisible corrosion of concrete reinforcing that involves a minimal amount of destructive works.

Steel corrosion usually occupies a much larger volume than un-corroded steel and result in bursting stresses that cause cracking, spalling or delamination of the concrete cover. By the time such damage becomes visible the extend of invisible damage has usually spread widely in the concrete structure. Half Cell Potectial highlights the degree of corrosion activity before rusting becomes visible.

The below map and graph shows the potential survey results carriedout on a jetty. The graph shows the measures in mV(megavolt) with different colours according to its magnitude; the minimum value obtain was -110 mV and max 35 mV (see the frequency % chart). Potentials more positive than -200mV indicate there is a greater than 90% probability that no reinforcing steel corrosion is occurring in that area.

Note: Black shown position of cracking

This half cell potential shows the minimum value obtain was -515mV and maximum -330mV. Potentials less positive than -350mV indicate there is a greater than 90% probability that reinforcing steel corrosion is occurring in that area.