Quantitative Correlation between the Degree of Reaction and Compressive Strength of Metakaolin-Based Geopolymers
For geopolymers (usually composed of unreacted precursor and gel), the compressive strength is controlled by two factors. The first is the degree of reaction, or, equivalently, the amount of gel formed, including any calcium silicate hydrate gel in calcium-containing mixtures. The second factor is t...
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2020-12-01
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| Online Access: | https://www.mdpi.com/1996-1944/13/24/5784 |
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| author | Xu Chen Eric Kim Prannoy Suraneni Leslie Struble |
| author_facet | Xu Chen Eric Kim Prannoy Suraneni Leslie Struble |
| author_sort | Xu Chen |
| collection | DOAJ |
| description | For geopolymers (usually composed of unreacted precursor and gel), the compressive strength is controlled by two factors. The first is the degree of reaction, or, equivalently, the amount of gel formed, including any calcium silicate hydrate gel in calcium-containing mixtures. The second factor is the gel composition, generally given by the Si/Al ratio. These two parameters are interrelated for typical silicate-activated metakaolin geopolymers. By separating out effects of Si/Al ratio and degree of reaction, this study quantitatively correlates the degree of reaction with the compressive strength of metakaolin-based geopolymers with and without calcium. Solid-state <sup>29</sup>Si nuclear magnetic resonance (NMR) aided with chemical extractions was used to determine gel amounts and composition for several geopolymer mixtures. The compressive strength was also measured for each mixture at 7 days. Both the increase of Na/Al ratio in mixtures without calcium and addition of external calcium increased the degree of reaction, and compressive strength correlated linearly (R<sup>2</sup> > 0.88) with the degree of reaction. |
| first_indexed | 2024-03-10T13:57:55Z |
| format | Article |
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| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-10T13:57:55Z |
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| spelling | doaj.art-367f845711b74bf886177c4d874eec762023-11-21T01:25:55ZengMDPI AGMaterials1996-19442020-12-011324578410.3390/ma13245784Quantitative Correlation between the Degree of Reaction and Compressive Strength of Metakaolin-Based GeopolymersXu Chen0Eric Kim1Prannoy Suraneni2Leslie Struble3Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 1111 Engineering Drive UCB 428, Boulder, CO 80309, USAExxonMobil Research & Engineering Company, North American Growth Venture, Olefins Furnaces, 3525 Decker Drive, Baytown, TX 77520, USADepartment of Civil, Architectural and Environmental Engineering, University of Miami, Coral Gables, FL 33146, USADepartment of Civil and Environmental Engineering, University of Illinois at Urbana Champaign, 205 N. Mathews Ave, Urbana, IL 61801 (emeritus), USAFor geopolymers (usually composed of unreacted precursor and gel), the compressive strength is controlled by two factors. The first is the degree of reaction, or, equivalently, the amount of gel formed, including any calcium silicate hydrate gel in calcium-containing mixtures. The second factor is the gel composition, generally given by the Si/Al ratio. These two parameters are interrelated for typical silicate-activated metakaolin geopolymers. By separating out effects of Si/Al ratio and degree of reaction, this study quantitatively correlates the degree of reaction with the compressive strength of metakaolin-based geopolymers with and without calcium. Solid-state <sup>29</sup>Si nuclear magnetic resonance (NMR) aided with chemical extractions was used to determine gel amounts and composition for several geopolymer mixtures. The compressive strength was also measured for each mixture at 7 days. Both the increase of Na/Al ratio in mixtures without calcium and addition of external calcium increased the degree of reaction, and compressive strength correlated linearly (R<sup>2</sup> > 0.88) with the degree of reaction.https://www.mdpi.com/1996-1944/13/24/5784geopolymernuclear magnetic resonancequantificationcompressive strength |
| spellingShingle | Xu Chen Eric Kim Prannoy Suraneni Leslie Struble Quantitative Correlation between the Degree of Reaction and Compressive Strength of Metakaolin-Based Geopolymers Materials geopolymer nuclear magnetic resonance quantification compressive strength |
| title | Quantitative Correlation between the Degree of Reaction and Compressive Strength of Metakaolin-Based Geopolymers |
| title_full | Quantitative Correlation between the Degree of Reaction and Compressive Strength of Metakaolin-Based Geopolymers |
| title_fullStr | Quantitative Correlation between the Degree of Reaction and Compressive Strength of Metakaolin-Based Geopolymers |
| title_full_unstemmed | Quantitative Correlation between the Degree of Reaction and Compressive Strength of Metakaolin-Based Geopolymers |
| title_short | Quantitative Correlation between the Degree of Reaction and Compressive Strength of Metakaolin-Based Geopolymers |
| title_sort | quantitative correlation between the degree of reaction and compressive strength of metakaolin based geopolymers |
| topic | geopolymer nuclear magnetic resonance quantification compressive strength |
| url | https://www.mdpi.com/1996-1944/13/24/5784 |
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