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Modelling of reinforcement corrosion – geometrical effects on macrocell corrosion / J. Warkus in Materials and corrosion, Vol. 61 N° 6 (Juin 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 494–504 Titre : Modelling of reinforcement corrosion – geometrical effects on macrocell corrosion Type de document : texte imprimé Auteurs : J. Warkus, Auteur ; M. Raupach, Auteur Année de publication : 2010 Article en page(s) : pp. 494–504 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : concrete;  corrosion;modelling;  reinforcement;  simulation Résumé : Reinforcement corrosion is still the most frequent reason for damage of concrete structures. It can be caused by carbonation or the ingress of chlorides. In cases of localized contaminations with chlorides, macrocells with very high corrosion rates can be established. Thereby the resulting macrocell current is dependent on many different boundary conditions like driving voltage, concrete resistivity and the geometrical arrangement of anode and cathode. In order to investigate macrocell corrosion, the herein presented research work was carried out by laboratory experiments and additionally by numerical analyses. First the numerical simulations were calibrated by laboratory measurements and thereafter, a numerical parameter study was carried out to increase the available database and identify the impact of changes in single parameters. As the focus is on geometrical effects, all laboratory specimens and numerical models were designed to represent practical conditions with diverse geometrical arrangements, e.g., slabs or beams with localized depassivations. In addition, parameters like concrete resistivity, driving voltage and cathode to anode surface area ratios have been varied. Thereafter, all results were used to derive cell factors for a simple macrocell current estimation. The present status of the project will be presented and discussed. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905437/abstract [article] Modelling of reinforcement corrosion – geometrical effects on macrocell corrosion [texte imprimé] / J. Warkus, Auteur ; M. Raupach, Auteur . - 2010 . - pp. 494–504. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 6 (Juin 2010) . - pp. 494–504 Mots-clés : concrete;  corrosion;modelling;  reinforcement;  simulation Résumé : Reinforcement corrosion is still the most frequent reason for damage of concrete structures. It can be caused by carbonation or the ingress of chlorides. In cases of localized contaminations with chlorides, macrocells with very high corrosion rates can be established. Thereby the resulting macrocell current is dependent on many different boundary conditions like driving voltage, concrete resistivity and the geometrical arrangement of anode and cathode. In order to investigate macrocell corrosion, the herein presented research work was carried out by laboratory experiments and additionally by numerical analyses. First the numerical simulations were calibrated by laboratory measurements and thereafter, a numerical parameter study was carried out to increase the available database and identify the impact of changes in single parameters. As the focus is on geometrical effects, all laboratory specimens and numerical models were designed to represent practical conditions with diverse geometrical arrangements, e.g., slabs or beams with localized depassivations. In addition, parameters like concrete resistivity, driving voltage and cathode to anode surface area ratios have been varied. Thereafter, all results were used to derive cell factors for a simple macrocell current estimation. The present status of the project will be presented and discussed. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905437/abstract