Symmetry effect on the dynamic behaviors of sandwich beams with periodic face sheets

We investigate theoretically and demonstrate experimentally, the effect of material geometric periodicity in face sheets on overall dynamics sandwich beams. By treating two core as separate entities using classic plate theory (CPT), conjunction with Bloch theorem, solving governing equations transfer matrix method (TMM) generalized differential quadrature (GDQM), we obtain a low-frequency \textit{total} bandgap which both transverse longitudinal waves are blocked beams glide-reflected (GR) sheets. On other hand, only \textit{partial} bandgaps blocking either or present ones mirror-reflected (MR) Furthermore, combination full-scale finite element (FEM) simulations experimental characterization provide unequivocal evidence these phenomenal wave features, well accuracy our theoretical results via defining displacement fields comparison effective periodic Timoshenko beam models. Our study indicates new mechanisms to suppress elastic by tuning sheet symmetry. explanation behaviors from structural symmetry point view also provides more comprehensive understanding propagation quasi-one-dimensional structures at large.