چكيده لاتين :
The nonlinear static pushover analysis technique is mostly used in the performance-based design of
structures and it is favored over nonlinear response history analysis. However, the pushover analysis with
FEMA load distributions losses its accuracy in estimating seismic responses of long period structures when
higher mode effects are important. Some procedures have been offered to consider this effect. FEMA and
Modal pushover analysis (MPA) are addressed in the current study and compared with inelastic response
history analysis. These procedures are applied to medium high-rise (10 and 15 storey) and high-rise (20 and
30 storey) frames; efficiency and limitations of them are elaborated. MPA procedure present significant
advantage over FEMA load distributions in predicting storey drifts, but the both are thoroughly unsuccessful
to predict hinge plastic rotations with acceptable accuracy. It is demonstrated that the seismic demands
determined with MPA procedure will be unsatisfactory in nonlinear systems subjected to individual ground
motions which inelastic SDF systems related to significant modes of the buildings respond beyond the elastic
limit. Therefore, itיs inevitable to avoid evaluating seismic demands of the buildings based on individual
ground motion with MPA procedure.
