Modelling of isothermal coupled moisture and ion transport in cementitious materials

Authors: V. Baroghel-Bouny, T.Q. Nguyen, M. Thiery, P. Dangla
Paper category: conference
Book title: Concrete Durability and Service Life Planning – ConcreteLife’09
Editor(s): K. Kovler
Print ISBN: 978-2-35158-074-5
e-ISBN: 978-2-35158-085-1
Publisher: RILEM Publications SARL
Publication year: 2009
Pages: 253 – 261
Total Pages: 9
Language: English

Abstract: Within the framework of the description and the prediction of moisture and chloride ion transport in concrete, a 1-D coupled numerical model has been developed in isothermal conditions on the basis of well-identified physical/chemical mechanisms. The ion transport process involves the species Cl-, OH-, Na+, K+, which are present in the pore solution, and is based on the extended Nernst-Planck equation, which accounts for advection of the liquid phase. The moisture transport process relies on the movements of both the water-vapour and dry-air mixture by diffusion/advection and of the liquid water due to capillary pressure gradients. Key material properties, such as transport coefficients and fluid-matrix interaction isotherms, are involved in the theoretical description and are therefore required as input data in the model. The governing differential equations of the model are summarized in the paper. In addition, examples of validation of the model in lab conditions are given in the case of wick action, as well as wetting (by salt solution) and drying cycles.

Online publication: 2012-05-16
Publication Type: full_text
Public price (Euros): 0.00