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arXiv · 1804.02188

Accordion-like metamaterials with tunable ultra-wide low-frequency band gaps

Anastasiia O. Krushynska·Ada Amendola·Federico Bosia·Chiara Daraio·Nicola M. Pugno·Fernando Fraternali
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Abstract

We study lightweight, elastic metamaterials consisting of tensegrity-inspired prisms, which present wide, low-frequency band gaps. For their realization, we alternate tensegrity elements with solid discs in periodic arrangements that we call "accordion-like" meta-structures. We show through analytical calculations and numerical simulations that these structures are characterized by low-frequency band gaps with strong uniform wave attenuation due to the coupling of Bragg scattering and local resonance mechanisms. This coupling helps to overcome the inherent limit of a narrow band-gap width for conventional locally-resonant metamaterials and to extend the wave attenuation to wider frequency ranges. Moreover, the band gaps can be further increased, provided a minimum structural damping is present, and tuned to desired frequencies by changing the applied prestress levels in the tensegrity structure. Results are corroborated by parametric studies showing that the band-gap frequencies are preserved for wide variations of geometric and material structural properties.

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Anastasiia O. Krushynska, Ada Amendola, Federico Bosia, Chiara Daraio, Nicola M. Pugno, Fernando Fraternali. 2018-04-06. Accordion-like metamaterials with tunable ultra-wide low-frequency band gaps. https://doi.org/10.1088/1367-2630%2Faad354

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