SIMPLE PREDICTOR OF MAXIMUM DISPLACEMENT OF SMRF BUILDINGS : Backbone curve of equivalent SDOF system and lateral load pattern for pushover analysis

Abstract

Predictors or estimates of seismic structural demands, such as inter-story drift angles, that are less time-consuming than nonlinear dynamic analysis can be useful for structural performance assessment and for design. The authors have proposed a predictor using the SRSS rule of modal composition, and taking into account a first-mode inelastic spectral displacement and a post-elastic first-mode shape approximated by the distribution of the story drifts obtained through a nonlinear static pushover analysis. This paper statistically investigates the dependence of the accuracy of the predictor on the lateral force distribution in the static pushover analysis and the backbone curve of an equivalent SDOF system using frame models with various stiffness distributions.