Title:
Analytical Method for Prediction of Water Permeability of Cement Paste
Author(s):
Jian-jun Zheng and Xin-zhu Zhou
Publication:
Materials Journal
Volume:
105
Issue:
2
Appears on pages(s):
200-206
Keywords:
cement paste; degree of hydration; water-cement ratio; water permeability.
DOI:
10.14359/19765
Date:
3/1/2008
Abstract:
In view of the importance of water transport in cement paste to durability assessment and design of cement-based materials, it is of great practical significance to determine its water permeability. This paper presents an analytical method for predicting water permeability of cement paste. Because capillary pores have a considerably larger scale and contribution to water permeability of cement paste than gel pores, cement paste is modeled as an isotropic two-phase composite material, with capillary and gel pores included in two separate phases. By introducing a hypothetical homogeneous medium of nonzero water permeability and applying the general effective medium theory, an analytical solution is derived for the water permeability of cement paste. The key parameter involved in the solution is then determined by experimental calibration. The primary advantage of the proposed method is that the morphological characteristics and physical properties of each phase constituent, the interaction of the two phases, and the Hashin-Shtrikman bounds are all taken into account. Finally, the validation of the analytical solution is verified with experimental results obtained from the literature. The paper concludes that the analytical solution presented in the paper can predict water permeability of cement paste with reasonable accuracy.