Modelling of constrained thin rubber layer with emphasis on damping

An interface finite element for the rubber layer in a steel–rubber–steel sandwich plate is developed. The novel element is based on a series expansion of the displacement field in the thickness direction. This technique makes it possible to achieve a high resolution of the displacement field in the thickness direction without adding more degrees-of-freedom in this direction. A fractional order viscoelastic model is used to describe the constitutive behavior of rubber. In particular, we consider a “Nitrile” type rubber and fit the model parameters to experiments. The purpose and the predictive capability of the interface element are investigated by calculating the harmonic response of sandwich plates. The results are then compared with measured responses as well as with responses obtained by a commercial general purpose finite element code and an analytical solution for a sandwich beam equation. Finally, we conclude that the interface element is accurate and efficient in the modelling of constrained rubber layers.