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Title: Surface wave propagation control with locally resonant metasurfaces using topology-optimized resonators
Locally resonant elastodynamic metasurfaces for suppressing surface waves have gained popularity in recent years, especially because of their potential in low-frequency applications such as seismic barriers. Their design strategy typically involves tailoring geometrical features of local resonators to attain a desired frequency bandgap through extensive dispersion analyses. In this paper, a systematic design methodology is presented to conceive these local resonators using topology optimization, where frequency bandgaps develop by matching multiple antiresonances with predefined target frequencies. The design approach modifies an individual resonator's response to unidirectional harmonic excitations in the in-plane and out-of-plane directions, mimicking the elliptical motion of surface waves. Once an arrangement of optimized resonators composes a locally resonant metasurface, frequency bandgaps appear around the designed antiresonance frequencies. Numerical investigations analyze three case studies, showing that longitudinal-like and flexural-like antiresonances lead to nonoverlapping bandgaps unless both antiresonance modes are combined to generate a single and wider bandgap. Experimental data demonstrate good agreement with the numerical results, validating the proposed design methodology as an effective tool to realize locally resonant metasurfaces by matching multiple antiresonances such that bandgaps generated as a result of in-plane and out-of-plane surface wave motion combine into wider bandgaps.  more » « less
Award ID(s):
1934527
PAR ID:
10560265
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
The Journal of the Acoustical Society of America
Date Published:
Journal Name:
The Journal of the Acoustical Society of America
Volume:
155
Issue:
5
ISSN:
0001-4966
Page Range / eLocation ID:
3172 to 3182
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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