Efficacy of pushover analysis methodologies: A critical evaluation

Various Pushover analysis methodologies have evolved as an easy as well as designers-friendly alternative of nonlinear dynamic analysis for estimation of the inelastic demands of structures under seismic loading for performance based design. In fact, the established nonlinear dynamic analysis to assess the same, demands considerable analytical and computational background and rigor as well as intuitive insight into inelastic behavior for judging suitability of the results and its interpretation and hence may not be used in design office for frequent practice. In this context, the simple and viable alternative of Pushover analysis methodologies can be accepted if its efficacy is thoroughly judged over all possible varieties of the problems. Though this burning issue has invited some research efforts in this direction, still a complete picture evolving very clear guidelines for use of these alternate methodologies require much more detailed studies, providing idea about how the accuracy is influenced due to various combinations of basic parameters regulating inelastic dynamic response of the structures. The limited study presented in the paper aims to achieve this end to the extent possible. The study intends to identify the range of applicability of the technique and compares the efficacy of various alternative Pushover analysis schemes to general class of problems. Thus, the paper may prove useful in judicial use of Pushover analysis methodologies for performance based design with reasonable accuracy and relative ease.