Interest of using a model combining carbonation/chloride ingress and depassivation to better anticipate the rehabilitation of concrete structures

Abstract

Mastering and optimizing the durability of concrete structures and also the rehabilitation of concrete structures is a major challenge for all actors of the concrete construction field. An experimental program is conducted to get a complete characterization of the mechanical, chemical and physical properties of four concretes and their performances towards the main aggressive environment for the reinforcement corrosion. The evaluated durability properties are chloride migration, porosity, water absorption and carbonation. Moreover, for each concrete, some reinforced specimens are manufactured to measure the electrochemical properties of the reinforcement such as potential. The project achievements are used to optimize and improve the durability model SDReaM-crete developed by Cerib and LMDC. This model can simulate the migration of chlorides, the combination of this migration with the mechanism of carbonation and the corrosion of reinforcing bars according to wetting-drying cycles. Finally, the present work aims to optimize the sizing of the cover thickness for new structures and to facilitate the lifespan prediction for existing structures. This paper describes the model SDReaM-crete and its recent improvements. Some experimental results and some interpretations as well as simulations made with SDReaM-crete are also presented.