Effect of calcium-rich compounds on setting time and strength development of alkali-activated fly ash cured at ambient temperature
| Autor: | Borwonrak Injorhor, Suksun Horpibulsuk, Sakonwan Hanjitsuwan, Tanakorn Phoo-ngernkham, Anurat Poowancum, Prinya Chindaprasirt |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
Calcium hydroxide
Materials Science (miscellaneous) Sodium 0211 other engineering and technologies chemistry.chemical_element 02 engineering and technology 021001 nanoscience & nanotechnology law.invention Portland cement chemistry.chemical_compound Compressive strength chemistry law Sodium hydroxide Fly ash 021105 building & construction lcsh:TA401-492 Hydroxide lcsh:Materials of engineering and construction. Mechanics of materials 0210 nano-technology Calcium oxide Nuclear chemistry |
| Zdroj: | Case Studies in Construction Materials, Vol 9, Iss, Pp-(2018) |
| ISSN: | 2214-5095 |
| Popis: | This paper investigates the effect of calcium-rich compounds on setting time and compressive strength development of alkali-activated fly ash (FA) pastes. Three calcium-rich compounds viz., Portland cement (PC), calcium hydroxide (CH) and calcium oxide (CaO) were used as additives to replace FA at the dosages of 5, 10, and 15% by weight basis. Sodium hydroxide and sodium silicate solutions were used as alkali activator liquids in all mixtures. Alkali activator liquid/solid binder (FA and calcium-rich compound) ratio of 0.60, sodium silicate-to-sodium hydroxide ratio of 2.0 and curing at ambient temperature (25 °C) were used for all mixes. Test results showed that the setting time and compressive strength of alkali-activated FA depended on the type and content of calcium-rich compound. The incorporation of all three calcium additives resulted in the acceleration of setting time. Alkali-activated FA with CH and PC could improve the strength development; however, the use of CaO resulted in the compressive strength reduction. The 28-day compressive strengths of alkali-activated FA with 15% PC and 5%, 10% and 15% CH met the strength requirement for repair material as specified by ASTM standard. The alkali-activated FA with additives can thus be used as an alternative repair binding material. Keywords: Alkali-activated fly ash, Calcium-rich compounds, Strength development, Alternative repair material |
| Databáze: | OpenAIRE |
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