Hydraulic conductivity and compressibility of mixtures of Nagoya clay with sand or bentonite

In this study, a series of incremental loading oedometer tests and microscopic observations is carried out in order to investigate the influence of sand/bentonite fractions on hydraulic conductivity and compressibility. If sand particles do not form a skeletal structure, and each particle is independent in the clay matrix, an additive fraction of sand causes a decrease in the compressibility; however, it does not affect the hydraulic conductivity under the same consolidation pressure. The additive fraction of bentonite contributes to a decrease in the hydraulic conductivity, even for clayey materials. In addition, the relationship between the pore-size parameter, which represents the pore entrance size distribution, and the hydraulic conductivity is discussed using a probabilistic model known as the general capillary model.