Effects of technological parameters on permeability estimation of partially saturated cement paste by a DEM approach

In this study, a numerical approach developed in our group is used to assess the permeability of partially saturated cement paste based on a discrete element modelling (DEM) technique. The relationship between saturation degree and permeability is found to be in good agreement with experimental observations. Also, outcomes of a systematic study of the effects of technological parameters (i.e., hydration period, water/cement ratio and cement particle size range) on the permeability of partially saturated specimens follow expected trends. Moreover, permeability is found to be correlated to effective porosity. This is a sound basis for investigating the impact of the interfacial transition zone on water and gas permeability. Effects of partial saturation are demonstrated different for water and gas transport. Possible mechanisms underlying these permeability characteristics are discussed in this paper.