Seismic evaluation of low and mid-rise steel special moment frames equipped with viscous dampers based on FEMA-P695 collapse prevention criteria

In this study, the seismic performance of steel special moment frames under the far field records with and without viscous dampers using FEMA P-695 has been evaluated. 4,8 and 12 story frames based on ASCE 7-10 ,AISC 360 have been designed considering viscous dampers features for a specific damping ratio of 15% (4,8 storey) , and 20% (model 12). Frames with dampers and without them with centralized plastic joints have been designed in opensees software with Bilin cyclic behavior. The frames have been scaled and analyzed based on non-linear incremental dynamic analysis (IDA) using 44 acceleration record of far field in a wide area as well as of seismic intensity. Seismic performance of the above mentioned frames has been offered in case of the probability of collapse, based on probabilistic analysis of seismic fragility. The results point out that in steel frames with viscous dampers at the probable level of 50% the collapsing capacity have raised up to 28%,88% and 74% relating to middle curve of non-linear incremental dynamic analysis. It has also been shown that the design of buildings with viscous dampers with 75% base cut have significantly influenced the reduction in the building weight and its costs as well as in the improvement in technical behavior and criteria.