ASSESSMENT OF MODAL PUSHOVER ANALYSIS AND CONVENTIONAL NONLINEAR STATIC PROCEDURE WITH LOAD DISTRIBUTIONS OF FEDERAL EMERGENCY MANAGEMENT AGENCY FOR HIGH-RISE BUILDINGS

摘要

The nonlinear static pushover analysis technique is mostly used in the performance-based design of structures. However, the pushover analysis with load distributions of Federal Emergency Management Agency (FEMA) loses its accuracy in estimating the seismic responses of long-period structures where higher mode effects are important. Recently, modal pushover analysis (MPA) has been proposed to consider these effects. Hence, FEMA load patterns and MPA are evaluated in the current study and compared with inelastic response history analysis. These approximate procedures are applied to medium-rise (10 and 15 stories) and high-rise (20 and 30 stories) buildings; advantages and limitations of them are elaborated. It is shown that MPA procedure presents significant advantage over FEMA load distributions in predicting story drifts. MPA is able to compute hinge plastic rotations better than FEMA load distributions at upper floor levels of high-rise buildings due to considering higher mode effects by this procedure, but both are unsuccessful in predicting hinge plastic rotations with acceptable accuracy.