A FINITE ELEMENT MODEL FOR HARMONICALLY EXCITED VISCOELASTIC SANDWICH BEAMS

Abstract A finite element model is presented for the harmonic response of sandwich beams with thin or moderately thick viscoelastic cores. Nonlinear variation of displacements through the thickness of the core is assumed. A simple approximation for the response of the core allows all core variables to be expressed in terms of the face plate displacements. The model uses standard beam shape functions to construct a 12 d.f. element, SANDWICH12. Driving point impedence predicted by the model agrees closely with experimental data, even at high frequencies. The model also predicts displacements at “resonant” driving frequencies that agree closely with available closed form solutions.