Influence des rapports eau/ciment et fines/ciment sur le comportement à l'état durci du béton autoplaçant à base de matériaux locaux algériens

International audiencehis paper describes the second phase of our research project on the influence of the composition parameters on the behaviour of unset and hardened self-compacting concrete (SCC). It studies the impact of the water/cement ratio and the fines/cement ratio on the behaviour of hardened SCC. Several tests were carried out, such as surface settlement, L box, sieving, bleeding, mechanical strengths, free shrinkage (drying shrinkage and autogeneous shrinkage) and a microstructure study (mineralogical characterization, pore space distribution), to better understand the roles of the various possible SCC components made with local materials and to identify the mechanisms governing shrinkage. We highlighted the role of the pore network and the microstructure of the hydrates. Results show good SCC optimization potential in Algeria. Our study helped develop several SCC formulations meeting the rheological criteria (good deformability, less bleeding, no segregation, better mechanical performance)