A micropolar model for the analysis of dispersive wavesin chiral mass-in-mass lattices
Journal Title: Frattura ed Integrità Strutturale - Year 2014, Vol 8, Issue 29
Abstract
The possibility of obtaining band gap structures in chiral auxetic lattices is here considered andapplied to the case of inertial locally resonant structures. These periodic materials are modelled as beam-latticesmade up of a periodic array of rigid rings, each one connected to the others through elastic slender ligaments.To obtain low-frequency stop bands, elastic circular resonating inclusions made up of masses located inside therings and connected to them through an elastic surrounding interface are considered and modeled. Theequations of motion are obtained for an equivalent homogenized micropolar continuum and the overall elasticmoduli and the inertia terms are given for both the hexachiral and the tetrachiral lattice. The constitutiveequation of the beam lattice given by the Authors [15] are then applied and a system of six equations of motionis obtained. The propagation of plane waves travelling along the direction of the lines connecting the ringcentres of the lattice is analysed and the secular equation is derived, from which the dispersive functions may beobtained.
Authors and Affiliations
A. Bacigalupo, L. Gambarotta
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