Latest revision as of 11:11, 22 May 2020

Abstract

This recommendation covers the description of non-destructive electrochemical test methods for the estimation in large size concrete structures of the instantaneous corrosion current densiti, ${\displaystyle i_{corr}}$, expressed in ${\displaystyle \mu A/cm^{2}}$, by means of the so called Polarization Resistance technique, ${\displaystyle R_{p}}$, in order to asses the condition of embedded steel reinforcement related to its corrosion. The values of ${\displaystyle i_{corr}}$, can be used to assess the rate of degradation of concrete structures affected by reinforcement corrosión. However, the cannot give information on the actual loss in steel cross section which, at present, only can be assessed by means of direct visual observation. Values of the free corrosión potential or half-cell potential, ${\displaystyle E_{corr}}$ [V], of the embedded reinforcing Steel and of the electrical concrete resistance, ${\displaystyle R_{e}~~\Omega }$, are obtained as preliminary steps of the ${\displaystyle R_{p}}$ measurements. Values of the concrete resistivity, ${\displaystyle \rho ~~[\Omega m]}$, can be calculated from ${\displaystyle R_{e}}$ values providing the geometrical arrangement of the electrodes enables this calculation. Both parameters, ${\displaystyle E_{corr}}$ and ${\displaystyle R_{e}}$ (or ${\displaystyle \rho }$) may be used to complement the reliability of the ${\displaystyle i_{corr}}$ measurements.

Full Document