Abstract
A procedure to estimate the mechanical and diffusive properties of cement pastes, mortars and concretes made with a novel CEM II/C-M (S-LL) binder that has been developed within the European EnDurCrete project, is presented in this paper. The objective is to set up a strategy able to determine the materials composition at different scales and in various configurations, and to provide reliable estimates of the properties. The phase assemblages of the cement pastes upon hydration, and further exposed to carbonation, leaching with water or chloride containing solutions, are first simulated using thermodynamic modeling. Different homogenization schemes are then applied, to estimate the mechanical and diffusive properties of the hydrated and degraded materials at different scales. The interfacial transition zone (ITZ) in mortar and concrete is accounted for by means of specific hypotheses regarding its thickness and the respective volume fraction of hydrates and capillary pores. The application of the differential scheme (DIF) at the cement paste scale, and at higher scales of the generalized self-consistent scheme (GSCS) or a procedure accounting for ITZ modeled as an interface combined with the DIF scheme, show a good consistency with the measured Young's modulus. In parallel, simulations are performed on 3D specimens composed of spherical particles surrounded by an ITZ layer to provide additional data for comparison. Numerical results and analytical estimations are found to be in excellent agreement. Finally, a specific study focusing on the effects of the ITZ on both mechanical and diffusive properties shows a significant impact of its thickness and its composition.
| Original language | English |
|---|---|
| Article number | 104537 |
| Journal | Cement and Concrete Composites |
| Volume | 131 |
| DOIs | |
| Publication status | Published - Aug 2022 |
| MoE publication type | A1 Journal article-refereed |
Funding
This project has received funding from the European Union under the research and innovation program Horizon 2020 , grant agreement No 760639 . This publication reflects only the authors' view and the Commission is not responsible for any use that may be made of the information it contains. We would like to express our gratitude to Barbara Lothenbach (Empa/NTNU) for the fruitful discussion concerning thermodynamic modeling. We are also indebted to Aljoša Šajna (ZAG) and Lucija Hanžič (ZAG) for the discussions to which they participated and for their continuous support of this project.
Keywords
- 3D computational analysis
- Interfacial transition zone (ITZ)
- Mechanical and diffusive properties
- Multi-scale modeling
- Novel cementitious material
- Thermodynamic modeling