Seismic Demand of Steel Structural Systems

Abstract Steel is the most useful material for construction of high rise buildings and large span structures for its immense strength, ductility and flexibility. Nonlinear static pushover analysis is recommended by FEMA to assess the actual behaviour of structures under seismic loading. Seismic codes consider a reduction in design loads by a factor called Response reduction factor (R) since the structures possesses significant reserve strength (Over strength) and capacity to dissipate energy (Ductility). The seismic demand parameters like Strength factor (Rs), Ductility factor (Rμ) are calculated using Capacity curve (Base shear Vs Roof displacement) obtained from displacement controlled pushover analysis. Steel structural systems like OMF, SMF, OMF with braces and OMF with shear wall of 10, 15 and 20 stories are designed and its performance is studied by pushover analysis using ETABS 2015. The present study focuses on the evaluation of Response reduction factor (R) for the structural system considered.