Sandwich beam theory and the analysis of constrained layer damping

This paper deals with the analysis of sandwich beams and constrained layer damping in beams. A three-layered beam theory has been given in which the continuity of displacements and the transverse shear stresses has been satisfied at the interfaces. Axial displacement field in each layer has been assumed to be non-linear with respect to the thickness co-ordinate. This resulted in a non-uniform shear stress variation across the thickness of each layer. Continuity conditions at the interfaces have been used in order to reduce the number of displacement parameters considerably. The final displacement parameters of the problem are only those corresponding to the base layer. The proposed sandwich beam theory has been used to predict the loss factors of a viscoelastically damped simply supported beam. Numerical results have shown that the existing models on constrained layer damping analysis are not suitable when the core is very thick (as is the case in sandwich beams) or when the core modulus is lower.