Modelling of nonlinear damping characteristics of a viscoelastic structural damper

Viscoelastic dampers, as supplementary damping devices, have been used in building structures under seismic loads. One of the challenging aspects in research and implementation of viscoelastic dampers is to evaluate the damping characteristics and the effect of the dampers on structures. A classical determination of damping is the measurement of the free vibrational decay of a beam. The objective of this study is to investigate a fundamental connection between viscoelastic material damping and structural damping in viscoelastic dampers based on linear viscoelastic theory and energy type damping models. Using the Timoshenko beam theory, the proposed formulation has been extended to derive the nonlinear damping characteristics of a cantilevered beam with an end-mass. The method is then used to show the effects of this nonlinear damping behaviour caused by steel rod structural dampers in a base-isolated structure under dynamic loads.