Experimental Study on Wave Propagation in One-Dimensional Viscoelastic Metamaterial

A locally resonant viscoelastic mass-spring cell is experimentally realized by a unit cell design fabricated by 3D printing. The standard linear solid model is introduced for the viscoelastic metamaterial. The complex band structures of both viscoelastic unit cell and elastic cases are presented to show the effect of viscoelasticity. Both the harmonic excitation and stochastic excitation are conducted on the finite viscoelastic metamaterial in experiments. Distinct wave attenuation is found in bandgap via sweep frequency response analysis under harmonic excitation. The experiments of the metamaterial under narrow-band noise excitation demonstrate good performance of wave attenuation in bandgap. Finally, the obtained bandgaps via numerical calculation are well consistent with the frequency ranges of wave attenuation from experiments, which confirm the effectiveness of the proposed viscoelastic model.