0000000001229996
AUTHOR
V. Gulizzi
showing 7 related works from this author
A computational framework for microstructural modelling of polycrystalline materials with damage and failure
2017
In the present thesis, a computational framework for the analysis of the deformation and damage phenomena occurring at the scale of the constituent grains of polycrystalline materials is presented. The research falls within the area of Computational Micro-mechanics that has been attracting remarkable technological interest due to the capability of explaining the link between the micro-structural details of heterogenous materials and their macroscopic response, and the possibility of fine-tuning the macroscopic properties of engineered components through the manipulation of their micro-structure. However, despite the significant developments in the field of materials characterisation and the…
NONLOCAL LAYER-WISE ADVANCED THEORIES FOR LAMINATED PLATES
2019
Eringen nonlocal layer-wise models for the analysis of multilayered plates are formulated in the framework of the Carrera Unified Formulation and the Reissner Mixed Variational Theorem (RMVT). The use of the layer-wise approach and RMVT ensures the fulfilment of the transverse stress equilibrium at the layers’ interfaces and allows the analysis of plates with layers exhibiting different characteristic lengths in their nonlocal behaviour. A Navier solution has been implemented and tested for the static bending of rectangular simply-supported plates. The obtained results favourably compare against available three-dimensional analytic results and demonstrate the features of the proposed theori…
Buckling and post-buckling of variable stiffness plates with cutouts by a single-domain Ritz method
2023
Structural components with variable stiffness can provide better performances with respect to classical ones and offer an enlarged design space for their optimization. They are attractive candidates for advanced lightweight structural applications whose functionalities often impose the presence of cutouts that requires accurate and effective analysis for their design. In the present work, a single-domain Ritz formulation is proposed, implemented and validated for the analysis of buckling and post-buckling behaviour of variable stiffness plates with cutouts. The plate model is based on the first-order shear deformation theory with nonlinear von Karman strain–displacement relationships. The p…
A BOUNDARY ELEMENT FORMULATION FOR MICROMECHANICAL HOMOGENIZATION OF POLYCRYSTALLINE MATERIALS WITH PIEZOELECTRIC COUPLING
2019
A novel boundary element formulation for the evaluation of the effective properties of threedimensional polycrystalline aggregates with piezoelectric coupling is presented. The aggregates are modelled at the scale of their constituent crystals and are artificially generated through Voronoi-Laguerre tessellations. The electro-mechanical behaviour of each crystal is represented upon introducing an ad-hoc mesh of its boundary and a generalised integral representation of the governing equations of the piezoelectric problem. The behaviour of the whole aggregate is then retrieved upon introducing a suitable set of electro-mechanical interface conditions at the grain boundaries. With respect to cl…
On the effects of suitably designed space microstructures in the propagation of waves in time modulated composites
2023
In the one-dimensional case, the amplitude of a pulse that propagates in a homogeneous material whose properties are instantaneously changed in time will undergo an exponential increase due to the interference between the reflected and transmitted pulses generated at each sudden switch. Here, we resolve the issue by designing suitable reciprocal PT-symmetric space-time microstructures so that the interference between the scattered waves is such that the overall amplitude of the wave will be constant in time in each constituent material. Remarkably, for the geometries proposed here, a pulse will propagate with constant amplitude regardless of the impedance between the constituent materials,…
IMPLICIT MESH DISCONTINUOUS GALERKIN FOR VARIABLE ANGLE TOW MULTILAYERED PLATES
2018
This works presents a novel computational scheme for variable angle tow (VAT) multilayered plates [1]. The characteristic features of the proposed scheme are the combined use of a discontinuous Galerkin (dG) formulation and an implicitly defined mesh. The formulation is based on the principle of virtual displacements (PVD) and the Equivalent Single Layer (ESL) assumption for the mechanical behavior of the VAT plates [2]. The problem is first placed within the dG framework by suitably introducing an auxiliary variable and by rewriting the set of equations governing ESL VAT plates as a firstorder system of differential equations. Following Arnold et al.[3] and by introducing suitably defined …
TRANSIENT AND FREE-VIBRATION ANALYSIS OF LAMINATED SHELLS THROUGH THE DISCONTINUOUS GALERKIN METHOD
2022
This paper presents a novel formulation for linear transient and free-vibration analysis of laminated shell structures based on Interior Penalty discontinuous Galerkin (DG) methods and variable-order through-the-thickness kinematics, whose combined use allows solving the shell problem with high-order accuracy throughout both the shell thickness and the shell modelling domain. The shell geometry is described via a generic system of curvilinear coordinates using either an analytical or a NURBS-based parametrization of the shell mid surface; the formulation also allows for the presence of cut-outs, which are implicitly represented by means of a level set function. After deriving the governing …