Influence of Mineral Admixtures on the Permeation Properties of Self-Compacting Concrete at Different Ages
Résumé
Due to its specific properties, the study of self-compacting concrete (SCC) represents an area of research that has strong potential for development. However, in spite of the interest of researchers in this new material, SCC has not yet gained universal acceptance as a construction material, and its application remains limited. The development of an economical SCC with interesting properties in the fresh and hardened state is important for the acceptance of such a concrete. Algerian natural source Pozzolan is rarely used in SCC due to the absence of any thorough study of its properties. This study investigates the permeation properties of SCC mixtures made with this Algerian natural Pozzolan, compared with conventional vibrated concrete and other SCC mixtures containing fly ash or limestone filler. Additionally, the correlations between chloride diffusion and sorptivity, and between apparent gas permeability and chloride diffusion, were investigated. Results indicate that, despite its economic benefits, SCC incorporating natural Pozzolan presents very low permeation properties (for example: lower migration coefficients compared to the SCC mixtures with limestone filler or ordinary vibrated concrete (difference > 50 % for results of the 30 MPa strength class). The relation between chloride diffusion and sorptivity, and between apparent gas permeability and chloride diffusion, is also confirmed.