There is a need to create a new generation of rehabilitation and design processes that integrate performance-based engineering principles. These include evaluating available capacities and structural strength then comparing them to deformation demands related to acceptable performance levels. This paper concerns with structural non-linear static analysis procedure (NSP) to investigate the performance of reinforced concrete (RC) buildings under seismic hazard. Two case studies of constructed high-rise buildings were analyzed using response spectrum analysis (RSA) and pushover analysis (POA) to evaluate the post-yield behavior, relative damage of the structure, story shears, roof displacement, story drifts, story moments, time period, plastic hinges formation, structure performance level and response modification factor (R). Based on the results of performance points for the two case studies, the buildings can sustain seismic base shear ranging from 85% to 65% of their ultimate capacity from POA in X- and Y-Directions. Furthermore, the calculated response modification factor differs from that prescribed by building codes. |