The work presented in this thesis is concerned with the theoretical and experimental investigation of free vibration of sandwich beams. An extensive literature review has been presented for sandwich beam construction, free and forced vibration of sandwich beams. The finite element method (FEM) has been employed to model the sandwich beam. Here the classical sandwich beam theory and higher order sandwich beam theory are used for Finite Element Method (FEM) modelling of sandwich beam with stiff rubber core and sandwich beam with soft foam core respectively. The free vibration analysis of the sandwich beam has been carried out. To validate the results of the free vibration of the sandwich beam, various experiments have been conducted. Here two types of sandwich beams are considered, sandwich beam with stiff core (aluminium-rubber-aluminium) and sandwich beam with soft core (aluminium-foam-aluminium). To know the material properties various tests such as tensile test and bending test have been conducted. The free vibration test of cantilever beam is done by First Fourier Transformation (FFT) analyser for pure aluminium, aluminium-rubber-aluminium and aluminium-foam-aluminium beams. By using finite element method natural frequencies are calculated. Finally comparison between analytical method and experimental method is done.
FEM, Free vibration, Sandwich beam, Viscoelastic core
