Ricerc@Sapienza

In this note a new hyperelastic model is proposed to reproduce the nonlinear
anisotropic reversible response of a wide class of geomaterials. The research
is motivated by the non-negligible role played by stress-dependent and anisotropic
elasticity, as combined with plasticity, in the modelling of the mechanical behaviour
of soils and soft rocks under both monotonic and cyclic loading conditions. In fact,
these aspects of the soil response often play a key role in the analysis of many
geotechnical boundary value problems.

Convergence of the rotational hardening variable α used in the anisotropic models of clay plasticity, with a constitutively defined attractor/bound αb(η), function of the stress ratio η, under fixed η loading, is analytically investigated. It is analytically shown that depending on various parameters of the rate equation of the evolution of α, such convergence may or may not occur despite the apparent necessity of convergence stemming from the form of the evolution equation of α.

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

This paper discusses the role of constitutive modelling in the context of modern sustainability-driven geotechnical engineering. The necessary definitions and fundamental relations among the elements characterising sustainability in civil and geotechnical engineering are first provided, based on the available scientific literature, to then introduce the key topic here discussed by some examples, characterised by increasing level of complexity in terms of constitutive modelling assumptions.

The variation of the Coriolis parameter with the latitude (beta effect) strongly affects the turbulent inverse cascade. In fact, when this effect holds, energy is preferentially transferred towards zonal modes. The consequent emergence of flow structures along the zonal direction can strongly impact transport and modify both zonal and meridional scalar diffusion. We performed a detailed analysis of Lagrangian tracers dispersion on rotating flows simulated in laboratory.

Cloaking and magnifying using radial anisotropy in non-integer dimensional space

The complex mode spectra of a grounded anisotropic dielectric slab (GADS) excited by a horizontal magnetic dipole are presented in the low THz range. A liquid crystal mixture with high birefringence, low dispersive behavior and moderate losses at THz frequencies is selected as anisotropic layer. The dispersion curves of the complex modes (in both the surface-wave and leaky-wave regime) supported by the GADS are compared to those supported by the equivalent isotropic grounded dielectric slab GDS with the ordinary and the extraordinary components of the liquid crystal permittivity tensor.