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Indexed by:期刊论文

Date of Publication:2014-06-27

Journal:PHYSICS LETTERS A

Included Journals:SCIE

Volume:378

Issue:32-33

Page Number:2436-2442

ISSN No.:0375-9601

Key Words:Nacre; Phononic crystal; Band gap; Vibration isolation; Finite element method

Abstract:The band structure of a nacreous composite material is studied by two proposed models, where an ultrawide low frequency band gap is observed. The first model (tension-shear chain model) with two phases including brick and mortar is investigated to describe the wave propagation in the nacreous composite material, and the dispersion relation is calculated by transfer matrix method and Bloch theorem. The results show that the frequency ranges of the pass bands are quite narrow, because a special tension-shear chain motion in the nacreous composite material is formed by some very slow modes. Furthermore, the second model (two-dimensional finite element model) is presented to investigate its band gap by a multi-level substructure scheme. Our findings will be of great value to the design and synthesis of vibration isolation materials in a wide and low frequency range. Finally, the transmission characteristics are calculated to verify the results. (C) 2014 Elsevier B.V. All rights reserved.