TY - JOUR
T1 - Microscopic effects on chloride diffusivity of cement pastes : a scale-transition analysis
AU - Pivonka, Peter
AU - Hellmich, C.
AU - Smith, David
PY - 2004
Y1 - 2004
N2 - For estimation of the durability of structures, it is highly desirable to quantify and simulate the chloride diffusion process in concrete. To this end, diffusion-cell experiments delivering the chloride diffusivity of cement pastes with different water-cement ratios (related to different microporosities) are evaluated in a scale-transition analysis. For prediction of the apparent chloride diffusivity, cement paste can be modelled by means of a differential homogenization scheme involving nondiffusive spherical inclusions in a diffusive matrix. As a result, chloride diffusivity of cement paste is obtained as a function of the microporosity and the chloride diffusivity in the micropore solution. Remarkably, the latter turns out to be one order of magnitude smaller than the chloride diffusivity in a pure salt solution system. The smaller diffusivity is probably caused by structuring of water molecules along the pore surface of cement paste. (C) 2004 Elsevier Ltd. All rights reserved.
AB - For estimation of the durability of structures, it is highly desirable to quantify and simulate the chloride diffusion process in concrete. To this end, diffusion-cell experiments delivering the chloride diffusivity of cement pastes with different water-cement ratios (related to different microporosities) are evaluated in a scale-transition analysis. For prediction of the apparent chloride diffusivity, cement paste can be modelled by means of a differential homogenization scheme involving nondiffusive spherical inclusions in a diffusive matrix. As a result, chloride diffusivity of cement paste is obtained as a function of the microporosity and the chloride diffusivity in the micropore solution. Remarkably, the latter turns out to be one order of magnitude smaller than the chloride diffusivity in a pure salt solution system. The smaller diffusivity is probably caused by structuring of water molecules along the pore surface of cement paste. (C) 2004 Elsevier Ltd. All rights reserved.
U2 - 10.1016/j.cemconres.2004.04.010
DO - 10.1016/j.cemconres.2004.04.010
M3 - Article
SN - 0008-8846
VL - 34
SP - 2251
EP - 2260
JO - Cement and Concrete Research
JF - Cement and Concrete Research
IS - 12
ER -