Influence of Accelerating Admixtures on the Reactivity of Synthetic Aluminosilicate Glasses
This research aims at gaining a further understanding of the impact of accelerating admixtures on the reactivity of supplementary cementitious materials (SCMs), which are widely used as a clinker replacement in blended cements. This was done on synthetic glasses with controlled composition and struc...
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MDPI AG
2022-01-01
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| Series: | Materials |
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| Online Access: | https://www.mdpi.com/1996-1944/15/3/818 |
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| author | Laura Gonzalez-Panicello Ines Garcia-Lodeiro Francisca Puertas Marta Palacios |
| author_facet | Laura Gonzalez-Panicello Ines Garcia-Lodeiro Francisca Puertas Marta Palacios |
| author_sort | Laura Gonzalez-Panicello |
| collection | DOAJ |
| description | This research aims at gaining a further understanding of the impact of accelerating admixtures on the reactivity of supplementary cementitious materials (SCMs), which are widely used as a clinker replacement in blended cements. This was done on synthetic glasses with controlled composition and structure that mimic two types of real SCMs (slag and calcium-rich fly ash). The effects of DEIPA, TIPA, NaSCN and Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub> on the glass dissolution, hydration kinetics and reaction products were investigated. The obtained results concluded that the pH of the NaOH solution and the composition of the synthetic glass play a key role on the effect of the admixtures. In 0.1 M NaOH (pH = 13.0), all the studied admixtures inhibited the dissolution of slag-like glasses while they enhanced the dissolution of Ca-rich fly ash-like glasses, being Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub> the admixture that led to the highest increase of the dissolution rate of the Ca-rich fly ash-type glasses. In 1 M NaOH solutions (pH = 13.8), only the alkali admixtures (NaSCN and Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub>) enhanced the degree of reaction of both glasses. In slag-type glasses pastes mixed with 1 M NaOH, the addition of 2% Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub> induced the highest increase of their reactivity as inferred by the total heat release and the amount of bound water. This is related to the formation of a high amount of S(II)-AFm, in addition to C-A-S-H, that would increase the aluminium undersaturation of the pore solution and consequently the further dissolution of the glass. |
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| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-09T23:38:04Z |
| publishDate | 2022-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-873b0c96b4a944d5ab0effdf0dbba3d72023-11-23T16:57:37ZengMDPI AGMaterials1996-19442022-01-0115381810.3390/ma15030818Influence of Accelerating Admixtures on the Reactivity of Synthetic Aluminosilicate GlassesLaura Gonzalez-Panicello0Ines Garcia-Lodeiro1Francisca Puertas2Marta Palacios3Eduardo Torroja Institute for Construction Science (IETcc-CSIC), 28033 Madrid, SpainEduardo Torroja Institute for Construction Science (IETcc-CSIC), 28033 Madrid, SpainEduardo Torroja Institute for Construction Science (IETcc-CSIC), 28033 Madrid, SpainEduardo Torroja Institute for Construction Science (IETcc-CSIC), 28033 Madrid, SpainThis research aims at gaining a further understanding of the impact of accelerating admixtures on the reactivity of supplementary cementitious materials (SCMs), which are widely used as a clinker replacement in blended cements. This was done on synthetic glasses with controlled composition and structure that mimic two types of real SCMs (slag and calcium-rich fly ash). The effects of DEIPA, TIPA, NaSCN and Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub> on the glass dissolution, hydration kinetics and reaction products were investigated. The obtained results concluded that the pH of the NaOH solution and the composition of the synthetic glass play a key role on the effect of the admixtures. In 0.1 M NaOH (pH = 13.0), all the studied admixtures inhibited the dissolution of slag-like glasses while they enhanced the dissolution of Ca-rich fly ash-like glasses, being Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub> the admixture that led to the highest increase of the dissolution rate of the Ca-rich fly ash-type glasses. In 1 M NaOH solutions (pH = 13.8), only the alkali admixtures (NaSCN and Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub>) enhanced the degree of reaction of both glasses. In slag-type glasses pastes mixed with 1 M NaOH, the addition of 2% Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub> induced the highest increase of their reactivity as inferred by the total heat release and the amount of bound water. This is related to the formation of a high amount of S(II)-AFm, in addition to C-A-S-H, that would increase the aluminium undersaturation of the pore solution and consequently the further dissolution of the glass.https://www.mdpi.com/1996-1944/15/3/818synthetic glassesreaction kineticsdissolutionaccelerating admixturesreaction products |
| spellingShingle | Laura Gonzalez-Panicello Ines Garcia-Lodeiro Francisca Puertas Marta Palacios Influence of Accelerating Admixtures on the Reactivity of Synthetic Aluminosilicate Glasses Materials synthetic glasses reaction kinetics dissolution accelerating admixtures reaction products |
| title | Influence of Accelerating Admixtures on the Reactivity of Synthetic Aluminosilicate Glasses |
| title_full | Influence of Accelerating Admixtures on the Reactivity of Synthetic Aluminosilicate Glasses |
| title_fullStr | Influence of Accelerating Admixtures on the Reactivity of Synthetic Aluminosilicate Glasses |
| title_full_unstemmed | Influence of Accelerating Admixtures on the Reactivity of Synthetic Aluminosilicate Glasses |
| title_short | Influence of Accelerating Admixtures on the Reactivity of Synthetic Aluminosilicate Glasses |
| title_sort | influence of accelerating admixtures on the reactivity of synthetic aluminosilicate glasses |
| topic | synthetic glasses reaction kinetics dissolution accelerating admixtures reaction products |
| url | https://www.mdpi.com/1996-1944/15/3/818 |
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