Hybrid Genetic Algorithm to Parameter Identification of Structural Systems with Added-Damping-and-Stiffness Device

The structural parameters may be deviated from the design values due to the yielding or the fatigue of the material strength. In this regard, the dynamic characteristics may also be changed due to the damage of the structure. In order to realize the dynamic behavior of structural systems, we can determine the dynamic models and parameters by system identification techniques. The method proposed for the parameter identification of nonlinear systems in this paper is the hybrid genetic algorithm combining Wen’s model as the restoring force model for each story shear. The process of exploring this algorithm is demonstrated by the simulated single-degree-of-freedom system. Finally, the method was applied to the three-story structural models with added-damping-and-stiffness devices mounted on the shaking table. The ground motion records used for these models are time histories of El Centro earthquake adjusted to different intensities. The results showed that the D20H100 model of added-damping-and-stiffness devices experienced slight damage when subjected to the excitation of the El Centro earthquake with PGA values equal to 500 gal and received more damage when the excitation increased to 600 gal.