Flexural wave attenuation by metamaterial beam with compliant quasi-zero-stiffness resonators

Abstract

A novel metamaterial beam with embedded quasi-zero-stiffness (QZS) resonator is proposed to realize wave attenuation in very low-frequency band gaps. The configuration of the QZS resonator is developed by using compliant mechanism with design optimization, and the feature of quasi-zero stiffness is achieved under proper pre-compression. Then, the dispersion relations of the metamaterial beam are derived by the transfer matrix method (TMM) to predicate the band gap theoretically. Additionally, the dynamic responses of the metamaterial beam are obtained by the spectral element method (SEM) to evaluate the transmittance of the flexural wave. Finally, the prototype of the metamaterial beam is fabricated by additive manufacturing, and the experimental investigation is conducted to verify the formation mechanism of the band gaps, which shows very low-frequency band gaps. Therefore, the QZS metamaterial beam should be promising in application for very low-frequency wave attenuation.