Résumé
This study was performed using recycled aggregates from two concrete sources, building and civil engineering concretes, whose compositions were fully controlled.Natural aggregates are completely replaced by pre-wetted coarse concretes aggregates in the composition of high-performance concrete (HPC) in order to enhance the internal curing phenomenon governed by the self-drying of the cement paste.Comparison of the mechanical performance and microstructural analysis of these second generation concretes revealed a secondary hydration of the cement paste by a mechanism of desorption of the water absorbed in the recycled coarse aggregate, a process of “internal curing”.These water transfers were characterized both on a global and local scale around recycled aggregates incorporated in C60 and C80 concretes. The water transfer capacity is optimal in C60 concrete paste (W/C = 0.33). The decrease in permeability and water porosity of the new paste is significant for these concretes compared to the control concretes based on natural aggregates.