New insights on homogenization for hexagonal-shaped composites as Cosserat continua

Abstract

In this work, particle composite materials with different kind of microstructures are analyzed. Such materials are described as made of rigid particles and elastic interfaces. Rigid particles of arbitrary hexagonal shape are considered and their geometry is described by a limited set of parameters. Three different textures are analyzed and static analyses are performed for a comparison among the solutions of discrete, micropolar (Cosserat) and classical models. In particular, the displacements of the discrete model are compared to the displacement fields of equivalent micropolar and classical continua realized through a homogenization technique, starting from the representative elementary volume detected with a numeric approach. The performed analyses show the effectiveness of adopting the micropolar continuum theory for describing such materials.

Time-History Analysis of Composite Materials with Rectangular Microstructure under Shear Actions

“…The results reported below investigate the behavior of a wall, clamped at the base and subjected to a distributed dynamic shear load applied at the top (Figure 3), in order to extend the numerical results already obtained for the static case [48] and to enrich the aspects related to the dynamic conditions [47]. Furthermore, a numerical evaluation, for the case in which blocks of different sizes are present in the masonry texture, wants to be performed, because in previous works, this aspect has been evaluated only in qualitative terms [25].…”

“…For this purpose, a timehistory analysis is used to determine the response of a structure under dynamic load. A homogenization technique, based on an energy equivalence criterion [23,24] between the discrete model, assumed as the benchmark, and the continuum model, is adopted to detect the anisotropic constitutive characteristics [48].…”

New prospects in non-conventional modelling of solids and structures

“…Non-classical continua are the subject of the third group of articles [9][10][11][12][13]. Sapora et al [9] deal with the typical borehole problem, modelled as a circular hole in an infinite elastic medium subjected to remote biaxial loading and/or internal pressure.…”

“…The study is substantiated by comparison with experimental data related to two different rock materials. Colatosti et al [10] analyze particle composite materials with different microstructures, modelled as an ensemble of rigid particles of arbitrary hexagonal shape and elastic interfaces. Considering a 2D panel with three different microstructure textures, static analyses are performed comparing the solutions of discrete, full unconstrained micropolar (Cosserat) and classical Cauchy models.…”

Mechanical characterization of composite materials with rectangular microstructure and voids

“…There are also many examples in which materials with voids [38][39][40] have been studied referring to Cosserat theory, such as foams [41][42][43][44], granular and geo-materials [45][46][47][48][49][50][51], cellular solids [52][53][54] and different kind of structures such as rods [55] and shells [56][57][58] or even multifield models with affine microstructure [5,7]. In order to extend the numerical investigations about the microstructured composite materials made of rigid particles and elastic thin interfaces [59][60][61], the goal is to test the efficiency of the homogenization technique adopted [62,63], to describe porous materials, not yet analyzed with this approach by the authors themselves [64][65][66]. The study is conducted both in static and dynamic conditions, varying the internal characteristics and then proposing a comparison between a discrete model and two continuous models, one micropolar and one classic.…”