A new model for estimating fluid transfer properties of cementitious materials

A model capable of predicting transport properties based solely on the pore size distribution of the material and the fluid characteristics has been developed previously by the authors. This model combines a Darcy description of the fluid flow at the macroscale with a Poiseuille/Knudsen flow at the micro-scale. A stochastic approach is then used with regards to pore network generation, in a manner consistent with mercury intrusion porosimetry (MIP). The present paper extends this model to multi-phase flow in an attempt to model partially saturated porous media. Kelvin's law defines which pore sizes are invaded with liquid and rules for accounting contributions of the pore network to liquid and vapour flows are introduced. The extended model provides data that are consistent with the Van Genuchten approach to liquid and gas relative permeabilities, compares well with experimental data and provides information of the relative permeability to vapour and liquid water upon damage. © ASCE.