Behaviour of steel reinforcement under the effect of strong cathodic or anodic polarizations

Abstract

The behaviour of highly polarized steel embedded in concrete was analysed using small mortar specimens and concrete beams, as well as slabs of considerable size, in the presence and absence of chloride additions. Electrochemical impedance spectroscopy (EIS) was used for the small samples, and polarization resistance was measured in the large ones. The measurements at corrosion potential provide information about the corrosion kinetics of steel embedded in concrete. The response under high cathodic polarizations provides information about the behaviour of the electrodes subjected to cathodic protection or forming galvanic macro-cells with highly electronegative metals. The response under high anodic polarizations can provide information about the behaviour of reinforcements exposed to erratic currents, or about the effect of galvanic macro-cells with metals much nobler than steel.