Nonlinear modeling of MDOF structures equipped with viscoelastic dampers with strain, temperature and frequency-dependent properties

The main objective of this paper is to propose a numerical algorithm for modeling the nonlinear time-history seismic response of MDOF structures with frequency-, strain- and temperature-dependent viscoelastic (VE) dampers. An extended recursive parameter model based on Nakamura's method is established in order to simulate the frequency-, strain- and temperature-dependent properties of VE dampers in the time domain. The numerical stability of the extended model combined with a time-stepping method is studied and the model is verified against the exact solution for linear response as well as the experimental measurements for nonlinear response. A full-fledged nonlinear time-history analysis of a practical engineering problem is carried out and the results are compared with those calculated by traditional Kelvin-Voigt model which is commonly used in the practice as well as fractional derivative (FD) method. The advantages and robustness of the proposed method is then fully discussed.