Influence of Initial Water Content on the Mechanical Behavior of Unsaturated Sandy Clay Soil

Abstract

AbstractThe mechanical behavior of a sandy clay soil was investigated by a series of constant water content triaxial tests on unsaturated samples with suction measurements. The tests were carried out in double-cell triaxial cells on compacted samples and also on samples wetted and dried from the as-compacted conditions. A series of tests on saturated samples was also performed to provide a reference state for the unsaturated tests. Because the specimens were at high degrees of saturation (generally >80%), calculations based on effective stress showed a reasonable interpretation of the data for the critical state parameters M and λ. However, the intercept of the critical state line in the ν-axis (Γ) differed and increased with an increase in water content (at compaction). The data were also analyzed using the Bishop stress (p*) approach, and a better fitting was achieved in the stress plane, where it was possible to define a unique critical state line, where M was 0.91. However, in the ν-p* plane, differen...