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Updated: Feb 24, 2026
06:27
Expression of Cementitious Pore Solution and the Analysis of Its Chemical Composition and Resistivity Using X-ray Fluorescence
Published on: September 23, 2018
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Effects of Relative Humidity on Dissolution and Carbonation Potential of Portlandite
Naohiko Saeki1, Ippei Maruyama1, Tulio Honorio2
1Department of Architecture, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan.
Langmuir : the ACS Journal of Surfaces and Colloids
|February 23, 2026
Summary
Understanding water
Area of Science:
- Materials Science
- Environmental Science
- Computational Chemistry
Background:
- Carbonation of cementitious materials offers a CO2 mitigation strategy.
- Interfacial reactions in thin water films govern cement carbonation.
- Water adsorption significantly influences carbonation kinetics.
Purpose of the Study:
- Investigate water adsorption on portlandite surfaces.
- Elucidate the mechanism of calcium dissolution and its dependence on humidity.
- Determine the role of water films in limiting carbonation.
Main Methods:
- Hybrid Grand Canonical Monte Carlo (GCMC)-Molecular Dynamics (MD) simulations.
- Well-tempered metadynamics for biased MD simulations.
- Experimental measurement of portlandite carbonation degree (DoC).
Main Results:
- Calcium dissolution threshold identified around 40% relative humidity (RH).
- Dissolved Ca adatoms exhibit limited mobility parallel to the surface.
- Water layer restricts perpendicular Ca movement, inhibiting CaCO3 nucleation and growth.
Conclusions:
- Water adsorption dictates calcium dissolution and surface reactivity.
- Humidity-dependent Ca behavior spatially limits complete cement carbonation.
- Simulation results align with experimental observations on carbonation thresholds.
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