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Measuring the corrosion rate of steel in concrete / P. V. Nygaard in Materials and corrosion, Vol. 63 N° 3 (Mars 2012) 

Public ISBD [article]  in Materials and corrosion > Vol. 63 N° 3 (Mars 2012) . - pp. 200–214 Titre : Measuring the corrosion rate of steel in concrete : effect of measurement technique, polarisation time and current Type de document : texte imprimé Auteurs : P. V. Nygaard, Auteur ; M. R. Geiker, Auteur Année de publication : 2012 Article en page(s) : pp. 200–214 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Corrosion  current  density;  corrosion  rate;  galvanostatic;  polarisation  resistance;  potentiodynamic,  reinforced  concrete;  reinforcement  corrosion Résumé : Both on-site investigations and laboratory studies have shown that different corrosion rates are obtained when different commercially available corrosion rate instruments are used. The different electrochemical techniques and the measurement parameters used, i.e. polarisation current and time, are in some studies considered the main reasons for the variations. This paper presents an experimental study on the quantitative effect of polarisation time and current on the measured polarisation resistance – and thus the corrosion current density – of passively and actively corroding steel. Two electrochemical techniques often used in instruments for on-site corrosion rate measurements are investigated. On passively corroding reinforcement the measured polarisation resistance was for both techniques found to be highly affected by the polarisation time and current and no plateaus at either short or long polarisation times, or low or high polarisation currents were identified. On actively corroding reinforcement a large effect of the polarisation time was also found, but only a minor effect of the polarisation current. The effect of the polarisation time was, however, practically independent of the corrosion rate for actively corroding steel. For both techniques guidelines for polarisation times and currents are given for (on-site) non-destructive corrosion rate measurements on reinforcement steel in concrete. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201005792/abstract [article] Measuring the corrosion rate of steel in concrete : effect of measurement technique, polarisation time and current [texte imprimé] / P. V. Nygaard, Auteur ; M. R. Geiker, Auteur . - 2012 . - pp. 200–214. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 63 N° 3 (Mars 2012) . - pp. 200–214 Mots-clés : Corrosion  current  density;  corrosion  rate;  galvanostatic;  polarisation  resistance;  potentiodynamic,  reinforced  concrete;  reinforcement  corrosion Résumé : Both on-site investigations and laboratory studies have shown that different corrosion rates are obtained when different commercially available corrosion rate instruments are used. The different electrochemical techniques and the measurement parameters used, i.e. polarisation current and time, are in some studies considered the main reasons for the variations. This paper presents an experimental study on the quantitative effect of polarisation time and current on the measured polarisation resistance – and thus the corrosion current density – of passively and actively corroding steel. Two electrochemical techniques often used in instruments for on-site corrosion rate measurements are investigated. On passively corroding reinforcement the measured polarisation resistance was for both techniques found to be highly affected by the polarisation time and current and no plateaus at either short or long polarisation times, or low or high polarisation currents were identified. On actively corroding reinforcement a large effect of the polarisation time was also found, but only a minor effect of the polarisation current. The effect of the polarisation time was, however, practically independent of the corrosion rate for actively corroding steel. For both techniques guidelines for polarisation times and currents are given for (on-site) non-destructive corrosion rate measurements on reinforcement steel in concrete. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201005792/abstract