Evaluation of seismic response modification factors for steel frames by non-linear analysis

Bakır, Serhan
In this study steel framing systems are investigated with regards to their lateral load carrying capacity and in this context seismic response modification factors of individual systems are analyzed. Numerous load resisting layouts, such as different bracing systems and un-braced moment resisting frames with various bay and story configurations are designed and evaluated in a parametric fashion. Three types of beam to column connection conditions are incorporated in evaluation process. Frames, designed according to Turkish seismic code, are investigated by nonlinear static analysis with the guidance of previous studies and recent provisions of FEMA. Method of analysis, design and evaluation data are presented in detail. Previous studies in literature, history and the theory of response modification phenomenon is presented. Results are summarized, main weaknesses and ambiguities introduced to design by the use of “R” factors are stated depending on the observed behavior.