Abstract:
This work reports a study carried out on the design and performance of galvanic
and polarization resistance sensors to be embedded in concrete systems for permanent
monitoring of the corrosion condition of reinforcing steel, aiming to establish a correlation
between the galvanic currents, Igal, and the corrosion currents, Icorr, estimated from the
polarization resistance, Rp. Sensors have been tested in saturated Ca(OH)2 aqueous
solutions, under a variety of conditions, simulating the most important parameters that can
accelerate the corrosion of concrete reinforcing steel, such as carbonation, ingress of
chloride ions, presence or absence of O2. For all the conditions, the influence of
temperature (20 to 55 ºC) has also been considered. From this study, it could be concluded
that the galvanic currents are sensitive to the various parameters following a trend similar
to that of the Rp values. A relationship between the galvanic and the corrosion current
densities was obtained and the limiting values of the Igal, indicative of the state condition of
the reinforcing steel for the designed sensor, were established
