Coarse-Grained Monte Carlo Simulations with Octree Cells for Geopolymer Nucleation at Different pH Values
Geopolymers offer a potential alternative to ordinary Portland cement owing to their performance in mechanical and thermal properties, as well as environmental benefits stemming from a reduced carbon footprint. This paper endeavors to build upon prior atomistic computational work delving deeper into...
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MDPI AG
2023-12-01
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| Series: | Materials |
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| Online Access: | https://www.mdpi.com/1996-1944/17/1/95 |
| _version_ | 1797358524631613440 |
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| author | Nicolas Castrillon Valencia Mohammadreza Izadifar Neven Ukrainczyk Eduardus Koenders |
| author_facet | Nicolas Castrillon Valencia Mohammadreza Izadifar Neven Ukrainczyk Eduardus Koenders |
| author_sort | Nicolas Castrillon Valencia |
| collection | DOAJ |
| description | Geopolymers offer a potential alternative to ordinary Portland cement owing to their performance in mechanical and thermal properties, as well as environmental benefits stemming from a reduced carbon footprint. This paper endeavors to build upon prior atomistic computational work delving deeper into the intricate relationship between pH levels and the resulting material’s properties, including pore size distribution, geopolymer nucleate cluster dimensions, total system energy, and monomer poly-condensation behavior. Coarse-grained Monte Carlo (CGMC) simulation inputs include tetrahedral geometry and binding energy parameters derived from DFT simulations for aluminate and silicate monomers. Elevated pH values may can alter reactivity and phase stability, or, in the structural concrete application, may passivate the embedded steel reinforcement. Thus, we examine the effects of pH values set at 11, 12, and 13 (based on silicate speciation chemistry), investigating their respective contributions to the nucleation of geopolymers. To simulate a larger system to obtain representative results, we propose the numerical implementation of an Octree cell. Finally, we further digitize the resulting expanded structure to ascertain pore size distribution, facilitating a comparative analysis. The novelty of this study is underscored by its expansion in both system size, more accurate monomer representation, and pH range when compared to previous CGMC simulation approaches. The results unveil a discernible correlation between the number of clusters and pores under specific pH levels. This links geopolymerization mechanisms under varying pH conditions to the resulting chemical properties and final structural state. |
| first_indexed | 2024-03-08T15:03:14Z |
| format | Article |
| id | doaj.art-4caaaff5d39549da9710d97ebfe0856c |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-08T15:03:14Z |
| publishDate | 2023-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-4caaaff5d39549da9710d97ebfe0856c2024-01-10T15:02:34ZengMDPI AGMaterials1996-19442023-12-011719510.3390/ma17010095Coarse-Grained Monte Carlo Simulations with Octree Cells for Geopolymer Nucleation at Different pH ValuesNicolas Castrillon Valencia0Mohammadreza Izadifar1Neven Ukrainczyk2Eduardus Koenders3Institute of Construction and Building Materials, Technical University of Darmstadt, Franziska-Braun-Str. 3, 64287 Darmstadt, GermanyInstitute of Construction and Building Materials, Technical University of Darmstadt, Franziska-Braun-Str. 3, 64287 Darmstadt, GermanyInstitute of Construction and Building Materials, Technical University of Darmstadt, Franziska-Braun-Str. 3, 64287 Darmstadt, GermanyInstitute of Construction and Building Materials, Technical University of Darmstadt, Franziska-Braun-Str. 3, 64287 Darmstadt, GermanyGeopolymers offer a potential alternative to ordinary Portland cement owing to their performance in mechanical and thermal properties, as well as environmental benefits stemming from a reduced carbon footprint. This paper endeavors to build upon prior atomistic computational work delving deeper into the intricate relationship between pH levels and the resulting material’s properties, including pore size distribution, geopolymer nucleate cluster dimensions, total system energy, and monomer poly-condensation behavior. Coarse-grained Monte Carlo (CGMC) simulation inputs include tetrahedral geometry and binding energy parameters derived from DFT simulations for aluminate and silicate monomers. Elevated pH values may can alter reactivity and phase stability, or, in the structural concrete application, may passivate the embedded steel reinforcement. Thus, we examine the effects of pH values set at 11, 12, and 13 (based on silicate speciation chemistry), investigating their respective contributions to the nucleation of geopolymers. To simulate a larger system to obtain representative results, we propose the numerical implementation of an Octree cell. Finally, we further digitize the resulting expanded structure to ascertain pore size distribution, facilitating a comparative analysis. The novelty of this study is underscored by its expansion in both system size, more accurate monomer representation, and pH range when compared to previous CGMC simulation approaches. The results unveil a discernible correlation between the number of clusters and pores under specific pH levels. This links geopolymerization mechanisms under varying pH conditions to the resulting chemical properties and final structural state.https://www.mdpi.com/1996-1944/17/1/953D off-lattice coarse-grained Monte Carloaluminosilicatesmetakaolinite-based geopolymeralkali silicate solutionnucleationcluster size distribution |
| spellingShingle | Nicolas Castrillon Valencia Mohammadreza Izadifar Neven Ukrainczyk Eduardus Koenders Coarse-Grained Monte Carlo Simulations with Octree Cells for Geopolymer Nucleation at Different pH Values Materials 3D off-lattice coarse-grained Monte Carlo aluminosilicates metakaolinite-based geopolymer alkali silicate solution nucleation cluster size distribution |
| title | Coarse-Grained Monte Carlo Simulations with Octree Cells for Geopolymer Nucleation at Different pH Values |
| title_full | Coarse-Grained Monte Carlo Simulations with Octree Cells for Geopolymer Nucleation at Different pH Values |
| title_fullStr | Coarse-Grained Monte Carlo Simulations with Octree Cells for Geopolymer Nucleation at Different pH Values |
| title_full_unstemmed | Coarse-Grained Monte Carlo Simulations with Octree Cells for Geopolymer Nucleation at Different pH Values |
| title_short | Coarse-Grained Monte Carlo Simulations with Octree Cells for Geopolymer Nucleation at Different pH Values |
| title_sort | coarse grained monte carlo simulations with octree cells for geopolymer nucleation at different ph values |
| topic | 3D off-lattice coarse-grained Monte Carlo aluminosilicates metakaolinite-based geopolymer alkali silicate solution nucleation cluster size distribution |
| url | https://www.mdpi.com/1996-1944/17/1/95 |
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