Recent decade has witnessed the improvement of performance-based earthquake engineering (PBEE) methods. Therefore, procedures to estimate performance levels of structures have developed in accuracy as well as simplification in practice. Incremental dynamic analysis (IDA) and modal pushover analysis are probably the most important methods in this aspect. IDA was identified as the state-of-the-art method to assess the performance level of structures by FEMA-350 but is a computational demanding technique. On the other hand, modal pushover analysis -despite its inherent approximate nature- is broadly used as the simplified nonlinear static method to evaluate seismic demands of structures. Recently these two methods have combined and constituted a more advanced method called MPA-based IDA which possesses the advantages of the two methods. In this paper, a comparative study is carried out to evaluate the reliability of MPA-based approximate method for regular and irregular RC plane frames. Results show that MPA-based IDA procedure is satisfactory for structural demands with a huge reduction in computational effort for regular buildings.

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