Effect of alkaline salts on calcium sulfoaluminate cement hydration
This work analyzes the effect of the presence of 5 wt.% of solid sodium salts (NaSO, NaCO, and NaSiO) on calcium sulfoaluminate cement (CSA) hydration, addresses hydration kinetics; 2-, 28-, and 90-d mechanical strength, and reaction product microstructure (with X-ray diffraction (XRD), and Fourier...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2021 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/257721 |
| Acceso en línea: | http://hdl.handle.net/10261/257721 |
| Access Level: | acceso abierto |
| Palabra clave: | calcium sulfoaluminate cement alkaline salts microstructure ettringite |
| Sumario: | This work analyzes the effect of the presence of 5 wt.% of solid sodium salts (NaSO, NaCO, and NaSiO) on calcium sulfoaluminate cement (CSA) hydration, addresses hydration kinetics; 2-, 28-, and 90-d mechanical strength, and reaction product microstructure (with X-ray diffraction (XRD), and Fourier transform infrared spectroscopy, (FTIR). The findings show that the anions affect primarily the reactions involved. Ettringite and AH, are the majority hydration products, while monosulfates are absent in all of the samples. All three salts hasten CSA hydration and raise the amount of ettringite formed. NaSO induces cracking in the ≥28-d pastes due to posthardening gypsum and ettringite formation from the excess SO present. Anhydrite dissolves more rapidly in the presence of NaCO, prompting carbonation. NaSiO raises compressive strength and exhibits strätlingite as one of its reaction products. |
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