Numerical and analytical investigation of cyclic behavior of steel ring dampers (SRDs)

In this study, the cyclic behavior of steel ring damper (SRD) was investigated through numerical and analytical methods. The present study was carried out to evaluate ductility and energy dissipation and providing an analytical equation to estimate the yielding capacity of SRDs. For this purpose, extensive parametric studies were performed using the finite element method. Parametric studies included investigating the effect of thickness, length, and diameter of steel ring on the behavior of SRD. Nonlinear static analysis was used to analyze finite element models under cyclic loading. Geometrical nonlinear behavior of materials and large deformations were considered in the modeling. Also, validation experiments were performed on experimental specimens for finite element models. Using the lower bound limit analysis and considering the effects of strain hardening, an equation was obtained to estimate the capacity of the steel ring. A good agreement was observed between results obtained from the measurement of yielding capacity using analytical equations and parametric studies. Also, yield force was found to be directly related to the length and diameter of the steel ring and yield stress. Results of parametric models and analytical relations showed that by increasing steel ring diameter, ductility and energy dissipation decreases and increases, respectively. Also, by increasing the diameter to thickness ratio (D/t), yield force, ductility, and energy dissipation decreased, respectively.