DYNAMICS OF GEOMETRICALLY EXACT SANDWICH STRUCTURES

A finite element formulation of a recent theory for geometrically exac t multilayer beams, applicable to one-dimensional plates, is presented here. The beam can take any arbitrary initial position in the two-dim ensional space. Each layer of the beam can have different material pro perties with no restriction on the stiffness, mass distribution and la yer thickness, thus allowing for the modeling of ideals sandwich struc tures. Finite rotation and shear deformation are accommodated for in e ach layer. The continuity of the displacements across the layer interf aces is exactly enforced; the deformed cross section is thus continuou s, piecewise-linear. Extensive numerical examples including harmonic r esponse of sandwich structures with three identical layers, with compa rison to single-layer beams, and the response of ideal sandwich beams to impact forces are presented to illustrate the applicability and ver satility of the proposed formulation. (C) 1997 Published by Elsevier S cience Ltd.