Influence Mechanism of the Interfacial Water Content on Adhesive Behavior in Calcium Silicate Hydrate−Silicon Dioxide Systems: Molecular Dynamics Simulations
The performance indicators of concrete are mainly determined by the interface characteristics between cement hydration slurry and aggregates. In this study, molecular dynamics technology was used to evaluate the effect of the interfacial water content on the evolution of the interface structure, int...
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MDPI AG
2023-07-01
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| author | Bin Ma Yunfan Chu Xiaolin Huang Bai Yang |
| author_facet | Bin Ma Yunfan Chu Xiaolin Huang Bai Yang |
| author_sort | Bin Ma |
| collection | DOAJ |
| description | The performance indicators of concrete are mainly determined by the interface characteristics between cement hydration slurry and aggregates. In this study, molecular dynamics technology was used to evaluate the effect of the interfacial water content on the evolution of the interface structure, interaction energy, and mechanical properties of calcium silicate hydrate (C-S-H) and silicon dioxide (SiO<sub>2</sub>) systems, and the weakening mechanism of the C-S-H/SiO<sub>2</sub> interface in a humid environment was revealed. The results showed that all stress–strain curves of C-S-H/SiO<sub>2</sub> were divided into the elastic stage and the failure stage. As the interfacial water layer thickened, the molecular weight of the water invading the C-S-H gradually increased, and the desorption of Ca<sup>2+</sup> ions in the surface region became significant, while the amount of Ca<sup>2+</sup> ions entering the water-layer region increased. The interaction energy of the C-S-H/SiO<sub>2</sub> progressively became larger, and the energy ratio (ER) significantly decreased; the tensile strength σc and residual strength σr of C-S-H/SiO<sub>2</sub> both showed a downward trend. In summary, a lower water content had a limited impact on the interfacial bonding strength, while the weakening effect enhanced with an increase in the interfacial water content. This phenomenon was also demonstrated in concrete interfacial bond strength experiments. |
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| language | English |
| last_indexed | 2024-03-11T01:46:23Z |
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| spelling | doaj.art-a81dbb362d6b4ea6ac6b76cd06b85cb32023-11-18T16:13:29ZengMDPI AGApplied Sciences2076-34172023-07-011313793010.3390/app13137930Influence Mechanism of the Interfacial Water Content on Adhesive Behavior in Calcium Silicate Hydrate−Silicon Dioxide Systems: Molecular Dynamics SimulationsBin Ma0Yunfan Chu1Xiaolin Huang2Bai Yang3School of Architecture and Transportation Engineering, Guilin University of Electronic Technology, Guilin 541004, ChinaSchool of Architecture and Transportation Engineering, Guilin University of Electronic Technology, Guilin 541004, ChinaSchool of Architecture and Transportation Engineering, Guilin University of Electronic Technology, Guilin 541004, ChinaSchool of Architecture and Transportation Engineering, Guilin University of Electronic Technology, Guilin 541004, ChinaThe performance indicators of concrete are mainly determined by the interface characteristics between cement hydration slurry and aggregates. In this study, molecular dynamics technology was used to evaluate the effect of the interfacial water content on the evolution of the interface structure, interaction energy, and mechanical properties of calcium silicate hydrate (C-S-H) and silicon dioxide (SiO<sub>2</sub>) systems, and the weakening mechanism of the C-S-H/SiO<sub>2</sub> interface in a humid environment was revealed. The results showed that all stress–strain curves of C-S-H/SiO<sub>2</sub> were divided into the elastic stage and the failure stage. As the interfacial water layer thickened, the molecular weight of the water invading the C-S-H gradually increased, and the desorption of Ca<sup>2+</sup> ions in the surface region became significant, while the amount of Ca<sup>2+</sup> ions entering the water-layer region increased. The interaction energy of the C-S-H/SiO<sub>2</sub> progressively became larger, and the energy ratio (ER) significantly decreased; the tensile strength σc and residual strength σr of C-S-H/SiO<sub>2</sub> both showed a downward trend. In summary, a lower water content had a limited impact on the interfacial bonding strength, while the weakening effect enhanced with an increase in the interfacial water content. This phenomenon was also demonstrated in concrete interfacial bond strength experiments.https://www.mdpi.com/2076-3417/13/13/7930interfacial water contentC-S-H/SiO<sub>2</sub> systeminfluence mechanismadhesive behaviormolecular dynamics |
| spellingShingle | Bin Ma Yunfan Chu Xiaolin Huang Bai Yang Influence Mechanism of the Interfacial Water Content on Adhesive Behavior in Calcium Silicate Hydrate−Silicon Dioxide Systems: Molecular Dynamics Simulations Applied Sciences interfacial water content C-S-H/SiO<sub>2</sub> system influence mechanism adhesive behavior molecular dynamics |
| title | Influence Mechanism of the Interfacial Water Content on Adhesive Behavior in Calcium Silicate Hydrate−Silicon Dioxide Systems: Molecular Dynamics Simulations |
| title_full | Influence Mechanism of the Interfacial Water Content on Adhesive Behavior in Calcium Silicate Hydrate−Silicon Dioxide Systems: Molecular Dynamics Simulations |
| title_fullStr | Influence Mechanism of the Interfacial Water Content on Adhesive Behavior in Calcium Silicate Hydrate−Silicon Dioxide Systems: Molecular Dynamics Simulations |
| title_full_unstemmed | Influence Mechanism of the Interfacial Water Content on Adhesive Behavior in Calcium Silicate Hydrate−Silicon Dioxide Systems: Molecular Dynamics Simulations |
| title_short | Influence Mechanism of the Interfacial Water Content on Adhesive Behavior in Calcium Silicate Hydrate−Silicon Dioxide Systems: Molecular Dynamics Simulations |
| title_sort | influence mechanism of the interfacial water content on adhesive behavior in calcium silicate hydrate silicon dioxide systems molecular dynamics simulations |
| topic | interfacial water content C-S-H/SiO<sub>2</sub> system influence mechanism adhesive behavior molecular dynamics |
| url | https://www.mdpi.com/2076-3417/13/13/7930 |
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