ABSTRACT
Compacted expansive clay is often considered as a possible engineered barrier in deep nuclear waste disposal. In order to study its hydro-mechanical behaviour, suction controlled oedometer tests are often carried out in laboratory. These tests provide most of the required mechanical parameters for numerical simulations using constitutive models such as BExM (Alonso et al., 1999). For the determination of hydraulic parameters, it is a common practice to establish the relationship between the hydraulic state of soil (degree of saturation) and soil suction through the water retention curve. From an experimental point of view, some studies on the coupling between mechanical stress, suction and degree of saturation have been performed on low-plastic soils (Tarantino & Tombolato, 2005); however, it has been rarely studied on compacted expansive clays.
