Jordan Journal of Civil Engineering

Evaluating Seismic Design Factors for Reinforced Concrete Frames Braced with Viscoelastic Damper Systems


Anis S. Shatnawi; Yousef H. Al-Qaryouti;


This study attempts to highlight the effects of viscoelastic damper bracings on the design seismic factors used for the design of reinforced concrete (RC) moment frames. The aim is to evaluate and provide the seismic response modification factor of RC ordinary moment frames (OMFs) which are braced with viscoelastic damping systems. Ductility and overstrength factors are also evaluated. These design factors have been also investigated for similar, but unbraced frames. The effect of number of stories has been considered in this study through using four-, eight-, twelve- and sixteen-story models. The frame members were designed by using linear response history analysis procedure. The analysis has been performed using nine different earthquake records to include the variability in seismic parameters of ground motions. Moreover, a nonlinear pushover analysis was employed with assigning nonlinear material behavior and plastic hinges to beams and columns, according to FEMA 356 code. It was found that the response modification, ductility and overstrength factors increased with increasing the number of stories. However, adding viscoelastic dampers further increased these seismic factors significantly.