Etude du transport des chlorures dans les matériaux cimentaires non saturés (validation expérimentale sur bétons en situation de marnage)

Reinforced concrete structures degradation as a result of steel corrosion is one of the most important causes for the construction service life reduction. Corrosion is due to chlorides penetration which can reach the reinforcement thought cracks or porosity. The ionic transport in the pore solution of the cement based materials depends on the saturation level of those materials. The case of unsaturated materials reflects better the reality of the marine concrete strucures even if this approach is less treated in the literature. The present study has the main objective to propose a transfer model which take into account the coupling between the transport of moisture and ions in cementitious materials. This study is divided in to three principal parts: in first part, we present the theoretical approach in order to establish the transfer equations in unsaturated materials. The second part is a numerical one, and it consists in solving the transport equations within the materials submitted to the marine environment through wetting and drying cycles. The last parts is experimental, it has a goal to validate to define the inputs of the model. The validation was done in laboratory simulator where concretes were submitted to the tidal zones cycles. We have shown a good agreement between the model and the experimental results. The model is also validated by using results of literature carried out mortars submitted to imbibitions drying cycles.LA ROCHELLE-BU (173002101) / SudocSudocFranceF