Synergistic effect of flexural wave broadband attenuation in beam with periodic-parallel constrained layer damping (P-PCLD)

The efficient suppression of broadband flexural waves is an important area of research. Owing to the multi-bandgap behaviors of parallel beams and the broadband wave attenuation characteristics of the constrained layer damping (CLD) treatment, their interaction mechanism might improve the flexural wave attenuation efficiency. Hence, in this study, a beam with a periodic parallel constrained layer damping (P-PCLD) was formed using Euler and sandwich beam parallel coupling. The wave propagation constant of the P-PCLD was derived based on the infinite periodic structure theory and evaluated using the finite element method. The practical benefit of the P-PCLD was first evaluated by studying the enhancement of the flexural wave suppression in sandwich beams (SBs) by adding parallel Euler beams. Further, the performance difference between the P-PCLD and constrained layer damping (CLD) treatments with a similar material weight was compared. The results showed that a reasonably designed P-PCLD could achieve better flexural wave attenuation performances than SBs or an equivalent weight CLD in both the low-frequency bandgap and passband range.