Lattice Boltzmann simulation of the ionic diffusivity in unsaturated cement paste

Author(s): Mingzhong Zhang, Yongjia He, Guang Ye, D.A. Lange, K. van Breugel
Paper category: Conference
Book title: 2nd International conference on Microstructural-related Durability of Cementitious Composites
Editor(s): Guang Ye, K. Van Breugel, Wei Sun, Changwen Miao
Print ISBN: 978-2-35158-129-2
e-ISBN: 978-2-35158-123-0
Publisher: RILEM Publications SARL
Pages: 1081 - 1089
Total Pages: 8
Language: English

Abstract: 
In order to assess the durability of concrete structures, it is essential to investigate the ionic diffusivity under unsaturated conditions. Simulation of the ioinc diffusivity in unsaturated cement-based materials is big challenge due to the complicated microstructures and the difficulties in modelling of multi-phase fluid flow in cement-based materials. In this study, the 3D microstructure of cement paste is obtained from X-ray μCT with a high resolution. In the simulation, the Shan-Chen multi-phase lattice Boltzmann model is modified to simulate the equilibrium distribution of water and gas in the obtained 3D microstructure at various degree of water saturation. A lattice Boltzmann diffusion model is applied to simulate the ionic diffusion and determine the ionic diffusivity based on Fick’s law. It was found that the ionic diffusivity shows a strong dependence on the degree of water saturation. The simulated results fit very well with the experimental data obtained from literature.

Online publication: 2013
Publication Type: full_text
Public price (Euros): 0.00