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Multiscale Mechanical Modelling of Complex Materials and Engineering Applications. In INTERNATIONAL JOURNAL FOR MULTISCALE COMPUTATIONAL ENGINEERING 5(2).Journal Special Issue (ISSN 1543-1649)
No full textP. TROVALUSCI / Foreword;
M. OSTOJA-STARZEWSKI, X. DU, Z.F. KHISAEVA and W. LI / Comparisons of the Size of Representative Volume Element in Elastic, Plastic, Thermoelastic and Permeable Random Microstructures;
K. SAB, A. CECCHI and J. DALLOT / Determination of the Overall Yield Strength Domain of Out-of-Plane Loaded Brick Masonry;
V. SANSALONE and P. TROVALUSCI /A numerical investigation of structure–property relations in fibre composite materials;
M.G.D. GEERS, R.L.J.M. UBACHS, M. ERINC, M.A. MATIN, P.J.G. SCHREURS and W.P. VELLINGA / Multi-scale analysis of microstructural evolution and degradation in solder alloys;
V.G. KOUZNETSOVA and M.G.D. GEERS / Modelling the interaction between plasticity and the austenite-martensite transformation;
F. CAMPI and I. MONETTO, Progressive Interface Failure under Shear Stresses Based on a Two-Dimensional Model of Decohesion;
G. BORINO, B. FAILLA and F. PARRINELLO / A nonlocal elastic-damage interface mechanical model;
F. DE ANGELIS / A variationally consistent formulation of nonlocal plasticit
ISRN Mechanical Engineering Journal
No full texthttp://www.isrn.com/journals/me/
ISRN Series; open access peer-reviewed journal
Highly Cited Award from ISI-WOS for the publication: P. Trovalusci et al., ‘Scale-dependent homogenization of random composites as micropolar continua’, Eur J Mech A/Solids. 49, 396–407, 2015
No full textComposites with different material symmetries. Discrete-micropolar continuum description
No full textParticle composites include materials like ceramic, metal composites, poly-crystals, and masonry. Due to the presence of different heterogeneities (rigid or soft inclusions, voids, microcracks, etc.) whose size may have an important impact on their behaviour at the macroscopic scale, mechanical modelling is a challenging task. Non-local theories offer a solution to this problem while maintaining memory of the microstructure, especially the internal length. Differently to local classical models, non-local models (micropolar/Cosserat might be considered non-local continua of implicit type [1]) can account for internal lengths in the field equations, which are significant in many cases. The aim of this work is the mechanical characterization of anisotropic composites made of rigid particles and thin elastic interfaces at different level scale for investigating both statical and dynamical behaviour [2-3]. To find the anisotropic constitutive properties of those materials, a homogenization technique based on an energy equivalence criterion between a discrete model of the material and a continuum one is adopted [4]. Two continuum model descriptions, one micropolar and the other classical, are compared to the discrete system, assumed as benchmark. Different material symmetry classes, both centrosymmetric and non-centrosymmetric, are considered and the advantages of micropolar modelling are highlighted.
[1] Trovalusci, P., Molecular Approaches for Multifield Continua: Origins and Current Developments. In Multiscale Modeling of Complex Materials; T. Sadowski, P. Trovalusci, Eds.; Springer: Vienna, Austria, 2014; pp. 211–27, DOI:10.1007/978-3-7091-1812-2_7
[2] Colatosti, M., Fantuzzi, N., Trovalusci, P. and Masiani, R., New insights on homogenization for hexagonal-shaped composites as Cosserat continua. Meccanica, 2021. https://doi.org/10.1007/s11012-021-01355-x
[3] Colatosti, M., Fantuzzi, N. and Trovalusci, P., Dynamic Characterization of Microstructured Materials Made of Hexagonal-Shape Particles with Elastic Interfaces. Nanomaterials 2021, 11, 1781, DOI: doi.org/10.3390/nano11071781
[4] Trovalusci, P. and Masiani, R., Material symmetries of micropolar continua equivalent to lattices, International Journal of Solids and Structures, 36(14), 2091-2108, 1999. DOI:10.1016/S0020-7683(98)00073-
Editorial
Full text linkIn this Special Issue we collect some selected and
invited novel contributions that follows and extend are
of the studies presented, at the ‘9th International
Conference on Computational Methods’
(ICCM2018), held in Rome, Italy in August 2018,
with Professor Trovalusci as Chairman. The present
Special Issue collects articles devoted to advanced
material behavior modelled using fractional computational
and mathematical models; high-performance
Finite Element Method for materials and structural
problems; Discrete Element Method for the application
to mechanical and geomechanical problems;
innovative lattice meta-materials within a computational
linear and nonlinear dynamics framework;
computational methods for nanocomposites, soft tissues
and masonry structures
Multiscale Modeling of Complex Materials. Phenomenological, theoretical and computational aspects (DOI 10.1007/ 978-3-7091-1812-2_3)
No full textPreface, by T. Sadowski, P. Trovalusci;
Atomistic-Continuum Couplings for Dynamic Fracture, by R. de Borst;
On the Method of Virtual Power in the Mechanics of Non-Classical Continua, by G. Del Piero;
Adaptive Concurrent Multi-level Modeling of Multi-scale Ductile Failure in Heterogeneous Metallic Materials, by S. Ghosh;
Fractals and Randomness in Mechanics of Materials, by M. Ostoja–Starzewski;
Modelling of Damage and Fracture Processes of Ceramic
Matrix Composites Under Mechanical Loading, by T. Sadowski
Multiscale Modeling of Damage in Composite Materials, by T. R. Talreja
Molecular Approaches for Multifield Continua: origins and
current developments, by P. Trovalusc
Int. Symposium On the Tectonics in Architecture: between Aesthetics and Ethics, P. Trovalusci
No full textDetails in the attached brochur
Modelli matematici per la muratura a blocchi considerata come sistema dotato di struttura (PhD Thesis:http://dsg.uniroma1.it/trovalusci/#selectedpapers)
No full textModellazione numerica di murature. Modelli discreti per murature a blocchi. Murature a tessitura regolare come continui dotati di struttura.Numerical modelling of masonry structures. Discrete models for brick- block masonry. Periodic masonry as continua with microstructure
The Effect of Micro-Polar Rotation in 2D Cosserat Solids
No full textIt has widely shown that the Cosserat model is able to describe homogenized continua in which particles and heterogeneity in general are described by an inner rotation termed microrotation [1-3]. Since the beginning, this additional degree of freedom has been properly introduced in reduced-dimensional structural models [4]. Many explicit solutions for Cosserat materials have been produced over years but the case, rather frequent, of orthotropic materials calls for the need of numerical investigations [1-3]. A peculiar feature of generalized continua is the presence of a material internal length [5]. The Cosserat continuum in particular, tends to behave as a Cauchy model when the internal characteristic length is close to the structural dimensions (macro-scale) but only if the material is isotropic or at least orthotetragonal [1]. Moreover, in the orthotropic case the relative rotation, which implies non-symmetries of the angular strain components, plays an important role that cannot be represented by generalized continua of other kinds (second gradient, couple stress, etc.) [2,3]. In the present work, the mechanical behaviour of Cosserat orthotropic two-dimensional block assemblies modeled as Cosserat is investigated paying attention to the material discontinuities and the scale effects. Different numerical approaches, using strong and weak form formulations, are adopted [6]. The results provided by two numerical techniques, the so-called Strong Formulation Finite Element Method (SFEM) [7] and the Finite Element Method, are compared. Convergence, stability and reliability of both numerical techniques will be discussed and advantages and disadvantages in terms of displacement/stress fields will be shown.
References
[1] Masiani, R. and Trovalusci P., “Cosserat and Cauchy materials as continuum models of brick masonry”, Meccanica, 31, 421-432 1996.
[2] Pau, A. and Trovalusci, P., Block masonry as equivalent micropolar continua: the role of relative rotations, Acta Mech, 223 (7), 1455-1471, 2012.
[3] Trovalusci, P. and Pau, A., “Derivation of microstructured continua from lattice systems via principle of virtual works: The case of masonry-like materials as micropolar, second gradient and classical continua”, Acta Mech, 225, pp.157-177 (2014).
[4] Altenbach, J., Altenbach H. and Eremeyev, V.A., “On generalized Cosserat-type theories of plates and shells: a short review and bibliography”, Arch Appl Mech, 80, pp.73-92 (2010).
[5] Sluys, L.J., de Borst, R. and Mühlhaus, H.-B., “Wave propagation, localization and dispersion in a gradient-dependent medium”, Int J Sol Struc, 30, pp.1153-1171 (1993).
[6] Fantuzzi, N., Leonetti, L., Trovalusci, P. and Tornabene, F., “Some Novel Numerical Applications of Cosserat Continua”, Intl J Comput Meth, 15, pp.1-38 (2018).
[7] Tornabene, F., Fantuzzi, N., Ubertini, F. and Viola, E., “Strong formulation finite element method based on differential quadrature: a survey”, Appl Mech Rev, 67, pp.1-55 (2015)
Dynamics for anisotropic homogenized materials
No full textMaterials such as ceramic and metal composites, poly-crystals, masonry, porous rocks are examples of particle composites: their macroscopic behavior is strongly dependent on the internal microstructure, moreover discontinuities and heterogeneities cannot be neglected. For these reasons, a non-local description is necessary to take into account the microscopic influence on the mechanical response. In this work the goal is to highlight the advantages of a description of these materials as micropolar continua compared to the classical continua. A homogenization technique, based on an energy equivalence criterion, between the discrete model, assumed as the benchmark, and the continuum model, is adopted to detect the anisotropic constitutive characteristics [1]. A possible numerical approach is presented in order to have a right identification of the representative volume element, needful for a correct homogenization [2].
Starting from other works of the same authors where the statics of two-dimensional bodies has been analysed [3-5], this study goes to further enrich the discussion and shows the influences of the material internal length on the dynamic response and consequently the necessity of a micropolar description. Particle composites with an internal microstructure made of three different hexagonal rigid blocks and thin elastic interfaces are considered at three different scale level, the numerical tests bring out how an increasing in the level of material anisotropy affect both frequencies and mode-shapes.
[1] P. Trovalusci and R. Masiani, “Material symmetries of micropolar continua equivalent to lattices,” Int. J. Solids Struct., vol. 36, no. 14, pp. 2091–2108, 1999, doi: 10.1016/S0020-7683(98)00073-0.
[2] M. Colatosti, N. Fantuzzi, P. Trovalusci, and R. Masiani, “New insights on homogenization for hexagonal-shaped composites as Cosserat continua”. Meccanica, 2021. https://doi.org/10.1007/s11012-021-01355-x
[3] N. Fantuzzi, P. Trovalusci, and R. Luciano, “Multiscale analysis of anisotropic materials with hexagonal microstructure as micropolar continua,” Int. J. Multiscale Comput. Eng., vol. 18, no. 2, pp. 265–284, 2020, doi: 10.1615/IntJMultCompEng.2020032920.
[4] N. Fantuzzi, P. Trovalusci, and R. Luciano, “Material symmetries in homogenized hexagonal-shaped composites as cosserat continua,” Symmetry, vol. 12, no. 3, pp. 1–21, 2020, doi: 10.3390/sym12030441.
[5] L. Leonetti, N. Fantuzzi, P. Trovalusci, and F. Tornabene, “Scale effects in orthotropic composite assemblies as micropolar continua: A comparison between weak and strong-form finite element solutions,” Materials, vol. 12, no. 5, 2019, doi: 10.3390/ma12050758
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