Influence of microstructural features on water, ion diffusion and transport in clay soils

Abstract The presence, distribution, and sizes of pore spaces, together with the continuity between them, and the interactions established therein are examined in terms of: (a) mechanisms associated with wetting and water uptake, (b) the role of soil composition on the development of microstructural units (MUs), and (c) the contribution of MUs to the macrostructural behaviour of a clay soil using viscometer measurements. A key element in the production of microstructure and distribution of pore spaces is the nature of the soil fractions comprising the clay soil. The influence of microstructure on the wetting of clay soils and water uptake performance is discussed in terms of hydration processes and film boundary transport. Viscometer measurements were used to assess soil composition and formational environments on soil microstructure.