New faster and non contacting measurement methods of polarization resistance measurment in the application to reinforcement corrosion

Trabajo presentado en el RILEM Symposium on On Site Assessment of Concrete, Masonry and Timber Structures - SACoMaTiS 2008, celebrado en Varenna (Italia), los días 1 y 2 de septiembre de 2008Polarization Resistance is now a routine technique well demonstrated to be able to measure the gravimetric loss due to corrosion in the majority of the electrolyte/ metal systems. Until now the determination of Rp has been made through using direct current or from the low frequency range when determining the electrochemical impedance. In order to measure metal corrosion it is necessary to make physical contact with the metallic piece which acts as working electrode. In present paper the feasibility of using a new method, Non Contacting Corrosion Technique, NCC, for polarizing the metal without the need of physical contact with it, is presented. The polarization is obtained through the induction of a current by means of an external electrical field. The model used for the calculation of the corrosion rate assumes that the current runs in parallel through the electrolyte and the metal and the current electrostatically polarizes the metal