Microprocessor controlled multiple half-cell measurements.

The well defined technique of half-cell potential measurements is one method of assessing the risk of corrosion in concrete. It is unique because it is the only direct non-destructive test available, but it is slow in practice, particularly when working on a small grid to obtain fine resolution. The introduction of a multiple cell array controlled by a microprocessor has improved both the rate at which the data are collected and presented. The system produces a map highlighting structural areas where corrosion is suspected by directly relating the half-cell values to the empirically derived Van Deveer criteria.