With viscoelastic damping materials the stiffness and damping properties are frequency and temperature dependent. Understanding of viscoelastic behaviour is essential for the efficient use and proper design of these materials for damping applications. The needed data has to be determined by the designer because it is typically not available. The determination of linear viscoelastic material parameters is typically based on dynamic mechanical thermal analysis (DMTA). The complex modulus is measured at several temperatures over a certain frequency range. Because of the limited frequency range the measured data is mathematically expanded as master curves. The complex modulus in frequency domain is converted to time domain resulting in the relaxation modulus. As a final step the results are transformed to a form applicable for finite element method (FEM) software. FE analysis was used for the validation of the generated material model of a damping epoxy. First the DMTA measurement setup was modelled using this material model implemented in Abaqus software. The complex modulus was calculated and compared to the measured values. As a more practical case a steel structure with a constrained layer damper was modelled. The calculated frequency responses were compared to the measured ones.
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