Influence of quartz powder and silica fume on the performance of Portland cement
| Autor: | Paulo Roberto Cetlin, Leonardo Martins Costa, Augusto Cesar da Silva Bezerra, Ludmila Rodrigues Costa Tavares, Joaquim Francisco Tavares Junior, Maria Teresa Paulino Aguilar |
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| Rok vydání: | 2020 |
| Předmět: |
Cement
Multidisciplinary Materials science Silica fume Science Carbonation 0211 other engineering and technologies Mechanical properties 02 engineering and technology Pozzolan 021001 nanoscience & nanotechnology Article law.invention Portland cement law 021105 building & construction Pozzolanic reaction Medicine Civil engineering Cementitious Composite material 0210 nano-technology Pozzolanic activity |
| Zdroj: | Scientific Reports Scientific Reports, Vol 10, Iss 1, Pp 1-15 (2020) |
| ISSN: | 2045-2322 |
| DOI: | 10.1038/s41598-020-78567-w |
| Popis: | Supplementary cementitious materials interact chemically and physically with cement, influencing the formation of hydrate compounds. Many authors have analyzed the filler and pozzolanic effect. 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. 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. The results indicate that SF is pozzolanic and that QP has no pozzolanic activity. 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 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. SF and QP increase the carbonation depth of the composites. SF and QP composites are efficient in the inhibition of the alkali-aggregate reaction. 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. |
| Databáze: | OpenAIRE |
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