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Reinforcement corrosion initiation and activation times in concrete structures exposed to severe marine environments / R.E. Melchers in Cement and concrete research, Vol. 39 N° 11 (Novembre 2009) 

Public ISBD [article]  in Cement and concrete research > Vol. 39 N° 11 (Novembre 2009) . - pp. 1068–1076 Titre : Reinforcement corrosion initiation and activation times in concrete structures exposed to severe marine environments Type de document : texte imprimé Auteurs : R.E. Melchers, Auteur ; C. Q. Li, Auteur Année de publication : 2010 Article en page(s) : pp. 1068–1076 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Corrosion;  Long-term  performance;  Chloride;  Reinforcement Index. décimale : 691 Matériaux de construction. Pièces et parties composantes Résumé : The corrosion of steel reinforcement bars in reinforced concrete structures exposed to severe marine environments usually is attributed to the aggressive nature of chloride ions. In some cases in practice corrosion has been observed to commence already within a few years of exposure even with considerable concrete cover to the reinforcement and apparently high quality concretes. However, there are a number of other cases in practice for which corrosion initiation took much longer, even in cases with quite modest concrete cover and modest concrete quality. Many of these structures show satisfactory long-term structural performance, despite having high levels of localized chloride concentrations at the reinforcement. This disparity was noted already more than 50 years ago, but appears still not fully explained. This paper presents a systematic overview of cases reported in the engineering and corrosion literature and considers possible reasons for these differences. Consistent with observations by others, the data show that concretes made from blast furnace cements have better corrosion durability properties. The data also strongly suggest that concretes made with limestone or non-reactive dolomite aggregates or sufficiently high levels of other forms of calcium carbonates have favourable reinforcement corrosion properties. Both corrosion initiation and the onset of significant damage are delayed. Some possible reasons for this are explored briefly. DEWEY : 620.13 ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science/article/pii/S000888460900163X [article] Reinforcement corrosion initiation and activation times in concrete structures exposed to severe marine environments [texte imprimé] / R.E. Melchers, Auteur ; C. Q. Li, Auteur . - 2010 . - pp. 1068–1076. Génie Civil Langues : Anglais (eng) in Cement and concrete research > Vol. 39 N° 11 (Novembre 2009) . - pp. 1068–1076 Mots-clés : Corrosion;  Long-term  performance;  Chloride;  Reinforcement Index. décimale : 691 Matériaux de construction. Pièces et parties composantes Résumé : The corrosion of steel reinforcement bars in reinforced concrete structures exposed to severe marine environments usually is attributed to the aggressive nature of chloride ions. In some cases in practice corrosion has been observed to commence already within a few years of exposure even with considerable concrete cover to the reinforcement and apparently high quality concretes. However, there are a number of other cases in practice for which corrosion initiation took much longer, even in cases with quite modest concrete cover and modest concrete quality. Many of these structures show satisfactory long-term structural performance, despite having high levels of localized chloride concentrations at the reinforcement. This disparity was noted already more than 50 years ago, but appears still not fully explained. This paper presents a systematic overview of cases reported in the engineering and corrosion literature and considers possible reasons for these differences. Consistent with observations by others, the data show that concretes made from blast furnace cements have better corrosion durability properties. The data also strongly suggest that concretes made with limestone or non-reactive dolomite aggregates or sufficiently high levels of other forms of calcium carbonates have favourable reinforcement corrosion properties. Both corrosion initiation and the onset of significant damage are delayed. Some possible reasons for this are explored briefly. DEWEY : 620.13 ISSN : 0008-8846 En ligne : http://www.sciencedirect.com/science/article/pii/S000888460900163X