Ricerc@Sapienza

In this paper a relationship between elastic anisotropy, as typically
observed in clayey soils subjected to shear wave propagation tests, and plastic
anisotropy, detected at yielding and leading to rotated yield loci, is proposed.
Furthermore, elastic and plastic anisotropies exhibit an evolving character, as a
consequence of the evolution of the fabric of the material induced, for example,
by irreversible straining. First, the theoretical implications of the above evolving
character of fabric, which leads to a new form of anisotropic elasto-plastic

In the present study the implications of a thermodynamic-based
constitutive framework on the mechanical behaviour of soils are critically
analysed. The primary advantage of this approach as compared to the traditional
hardening plasticity is that the models are guaranteed to obey the laws of
thermodynamics. Furthermore, the use of potential functions allows to introduce
some crucial ingredients of the mechanical behaviour of soils that directly affect
the shape of the yield surface and the flow rule of the model. To illustrate the