Reinforced Concretes of Tomorrow: Corrosion Behaviour according to Exposure Classes

Reinforced concrete is the most widely used building material but its durability in terms of concrete cover performance and corrosion of steel rebar is still a key point to be studied. To address this topic, within the frame of the national project PERFDUB, two series of eleven reinforced concrete specimens (with metric dimensions) were cast with innovative concrete mixes representative of the French experience, two shapes of rebar and two concrete covers. Then, these specimens were exposed in two natural exposure sites, one in Epernon for carbonation (XC4) and a second one in La Rochelle in the Atlantic Ocean in a tidal zone for chloride ions (XS3m). Their corrosion was carried out using non-destructive testing. In addition, in order to follow the corrosion evolution more accurately in a continuous way, two series of three specimens were casted with embedded sensors and were exposed in two other outdoor sites in Marne-la-Vallée (XC4) and in Eqiom facility (XS3e). The first results of this 20-year project in terms of corrosion of these reinforced concrete specimens obtained with laboratory and field equipment and with monitoring are presented in this paper

Méthode des élements finis espace-temps (adaptation du maillage en cours d'évolution avec contact)

MONTPELLIER-BU Sciences (341722106) / SudocSudocFranceF

Formulation thermodynamique d'une loi de comportement d'un matériau quasi-fragile couplant élasticité, endommagement et frottement : Application au béton

De nos jours, le bon fonctionnement des ouvrages en béton nécessite la prise en compte d’un des phénomènes majeurs de dégradation, la fissuration. Dans ce travail, une formulation d'un modèle prenant en compte l'endommagement, les déformations résiduelles et, partiellement les effets unilatéraux propres au béton est présentée. Afin de montrer les capacités de cette formulation, elle est appliquée à une étude à la rupture d'une poutre en béton armé

Modélisation du comportement mécanique de l'interface acier béton en présence de corrosion

Une modélisation de l'interface acier-béton en présence de corrosion est proposée en introduisant deux échelles permettant : - d’élaborer une loi de comportement de l’interface acier-béton prenant en compte les traits majeurs du phénomène de corrosion - de proposer une implantation numérique dans un cadre de calcul simplifié en vue de rendre possible le calcul de structure à grande échelle. Des exemples d’estimation de capacité portante résiduelle de structures corrodées seront présentés

Concrete of tomorrow: corrosion performances in marine environment

Concrete is the most used construction material worldwide, but if often faces durability issues due to rebar corrosion, and cement production can be energy consuming. Attempts to improve its resilience versus corrosion while reducing its carbon footprint are ongoing at an international level. In this objective, in France within the framework of the national project PERFDUB, a series of reinforced concrete walls were cast with innovative concrete designs, two shapes of rebars and two concrete covers. The standard performances of the different concrete mix designs were evaluated at a laboratory scale. Then the walls were exposed in the French La Rochelle harbor, in the tidal zone in order to monitor the evolution of the corrosion of the bars for a period of twenty years. The first results of the electrochemical follow-up of these reinforced walls are presented in this paper