Permeability and microstructure of concrete: a review of modelling

The durability of a concrete stucture is largely dependent on the possibilities of ingress of water, gases and ions into the porous material. Consequently, the microstructural characteristics of the material affect its transport properties. The most important parameters controlling penetration of external agents are : the size of the pores, of the microcracks and their connectivity ; the nature of the phases and their reactivity with various chemical species. Different models have been suggested to predict transfer coefficients in porous media. These models help engineers analyse the effect of the microstructural parameters and improve concrete durability. A modelling approach is presented in which porous characteristics are related to concrete permeability.