eprintid: 3669 rev_number: 8 eprint_status: archive userid: 69 dir: disk0/00/00/36/69 datestamp: 2017-03-21 12:00:57 lastmod: 2017-03-21 12:00:57 status_changed: 2017-03-21 12:00:57 type: monograph metadata_visibility: show creators_name: Bacigalupo, Andrea creators_name: Gambarotta, Luigi creators_id: andrea.bacigalupo@imtlucca.it creators_id: title: Dispersive wave propagation in two-dimensional rigid periodic blocky materials with elastic interfaces ispublished: submitted subjects: T1 divisions: CSA full_text_status: public monograph_type: working_paper abstract: Dispersive waves in two-dimensional blocky materials with periodic microstructure made up of equal rigid units having polygonal centro-symmetric shape with mass and gyroscopic inertia, connected each other through homogeneous linear interfaces, have been analysed. The acoustic behavior of the resulting discrete Lagrangian model has been obtained through a Floquet-Bloch approach. From the resulting eigenproblem derived by the Euler-Lagrange equations for harmonic wave propagation, two acoustic branches and an optical branch are obtained in the frequency spectrum. A micropolar continuum model to approximate the Lagrangian model has been derived based on a second-order Taylor expansion of the generalized macro-displacement field. The constitutive equations of the equivalent micropolar continuum have been obtained, with the peculiarity that the positive definiteness of the second-order symmetric tensor associated to the curvature vector is not guaranteed and depends both on the ratio between the local tangent and normal stiffness and on the block shape. The same results has been obtained through an extended Hamiltonian derivation of the equations of motion for the equivalent continuum that is related to the Hill-Mandel macro homogeneity condition. Moreover, it is shown that the hermitian matrix governing the eigenproblem of harmonic wave propagation in the micropolar model is exact up to the second order in the norm of the wave vector with respect to the same matrix from the discrete model. To appreciate the acoustic behavior of some relevant blocky materials and to understand the reliability and the validity limits of the micropolar continuum model, some blocky patterns have been analysed: rhombic and hexagonal assemblages and running bond masonry. date: 2016 date_type: published publisher: arXiv pages: 43 id_number: arXiv:1611.01265 institution: IMT Institute for Advanced Studies Lucca official_url: https://arxiv.org/abs/1611.01265 citation: Bacigalupo, Andrea and Gambarotta, Luigi Dispersive wave propagation in two-dimensional rigid periodic blocky materials with elastic interfaces. Working Paper arXiv (Submitted) document_url: http://eprints.imtlucca.it/3669/1/1611.01265.pdf