This additional C–S–H fills the gaps in the paste by promoting pore refinement and cementitious matrix thickening 12. Pozzolanic materials, such as silica fume, react chemically with the calcium hydroxide generated in cement hydration and produce additional calcium silicate hydrate (C–S–H) and other hydrated compounds (pozzolanic reaction) 7, 10, 11. SCM with cementing properties, such as blast furnace slag, result in hydrous compounds with similar chemical composition and structure to Portland cement hydration products 9. ![]() In these composites, SCM can act as cementing, pozzolanic or filler materials 7, 8. The results indicate that, unlike the filler effect, the occurrence of pozzolanic reaction strongly influences electrical resistance, reducing the risk of corrosion of the reinforcement inserted in the concrete.Ĭementitious composites with a low environmental impact associated with high mechanical performance and good durability indicators can be produced using supplementary cementitious materials (SCM) 1, 2, 3, 4, 5, 6. SF and QP composites are efficient in the inhibition of the alkali-aggregate reaction. SF and QP increase the carbonation depth of the composites. The microstructure with fewer pores of SF compounds indicates that the pozzolanic reaction reduced pore size and binding capability, resulting in equivalent mechanical properties, reduced permeability and increased electrical resistance of the composites. The use of SF and QP reduces the released energy at early times to the control paste, indicating that these materials reduce the heat of hydration. The results indicate that SF is pozzolanic and that QP has no pozzolanic activity. ![]() This study investigates the influence of the replacement of 20% of Portland cement for silica fume (SF) or a 20-µm medium diameter quartz powder (QP) on the properties of cementitious composites from the first hours of hydration to a few months of curing. However, few studies have explored the influence of these effects on hydration, properties in the fresh and hardened states, and durability parameters of cementitious composites separately. Many authors have analyzed the filler and pozzolanic effect. Supplementary cementitious materials interact chemically and physically with cement, influencing the formation of hydrate compounds.
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