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Characterization of effective moisture diffusivity based on pore structure of concrete
Osamah H A Dehwah1, H'mida Hamidane2,3, Yunping Xi2
1Department of Civil, Environmental and Architectural Engineering, University of Colorado Boulder, Boulder, CO, 80309, USA. Osamah.Dehwah@colorado.edu.
Scientific Reports
|August 8, 2024
Summary
This study introduces a new model for concrete's moisture diffusivity, considering pore size and diffusion types. The model accurately predicts moisture transport, enhancing concrete durability predictions.
Area of Science:
- Materials Science
- Civil Engineering
- Chemical Engineering
Background:
- Concrete durability relies on controlling aggressive chemical ingress.
- Moisture diffusion is crucial for cementitious material performance and chemical transport.
- Pore size distribution significantly impacts moisture diffusivity in concrete.
Purpose of the Study:
- To develop a theoretical model for concrete pore size volume fractions.
- To incorporate Molecular, Knudsen, and Surface diffusion mechanisms.
- To calculate effective moisture diffusivity based on pore structure and diffusion types.
Main Methods:
- Developed a theoretical model to determine pore size volume fractions.
- Calculated effective moisture diffusivity using a weighted average of diffusion mechanisms.
- Validated the model against experimental data for moisture diffusivity.
Main Results:
- The model successfully predicts pore size volume fractions for different diffusion mechanisms.
- An effective moisture diffusivity was accurately determined using the proposed model.
- Model predictions showed good agreement with existing experimental data.
Conclusions:
- The developed model provides a comprehensive approach to understanding concrete pore structure's impact on moisture diffusivity.
- This research offers valuable insights for improving material models and predicting concrete durability.
- The findings are crucial for enhancing the long-term performance assessment of cementitious materials.
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