W-shaped broadband attenuation of longitudinal waves through composite elastic metamaterial

• DOI: 10.1016/j.compositesb.2025.112250
• Publication Date: 2025-02-18T18:05:00Z
• Authors: Brahim Lemkalli; Krzysztof K. Dudek; Muamer Kadic; Qingxiang Ji; Sébastien Guenneau; Abdellah Mir; Younes Achaoui
• Keywords: Acoustic attenuation

This work was published in the journal Composites Part B: Engineering<br/>We investigate a composite elastic meta-slab with exceptional transmission properties, particularly the presence of a W-shaped bandgap. A comprehensive study, utilizing experimental measurements, the finite element method, and an analytical approach, identifies this specific bandgap. The meta-slab design involves cutting an array of composite materials arranged in parallel with strategically placed incisions. This configuration ensures that the materials between the slits act as plate-like waveguides within the surrounding medium. The incorporation of steel into ABS-based Fabry-Perot cavities induces a notable coupling effect between longitudinal waves and localized modes traversing the structure, leading to the formation of two distinct Fabry-Perot resonators. These coupling effects generate a series of resonances and antiresonances, ultimately producing the W-band gap through the interaction of two symmetric Fano resonances.<br/>