Self-compacting concrete (SCC) behaviour incorporating limestone fines as cement and sand replacement.

Owing to their high intrinsic properties, limestone fines (LF) seems to be a good replacement material of cement and/or sand, elaborating thus a new concrete without affecting its performances and properties. The present work aims at using, however, this natural material as an alternative cement or sand replacement, and investigating its influence on self-compacting concrete (SCC) properties at fresh and hardened states. Achieving this, several parameters have been examined, in terms of compressive strength, water permeability, chloride-ion penetration, gas permeability, water porosity and sorptivity. A total of 11 SCC mixes samples have been produced in two series, each one with different rate substitution (0%, 5%, 10%, 15%, 20% and 25%) of sand and cement. Our experimental data revealed the incorporation of LF up to 20% in SCC as partial replacement of sand and cement at fresh state, led to appreciable properties results. Nevertheless, at hardened state, at 15% for sand replacement an increase in compressive strength and a decrease in the water and chloride-ion diffusion, while an increase in the gas diffusion has been registered. And for cement replacement at 5%, an improvement in compressive strength and chloride ions diffusion was noted, whereas the water permeability and the gas diffusion decreased at 15% of LF substitution, where these results are widely discussed and explained in this paper. [ABSTRACT FROM AUTHOR]