@article { author = {Mofid, M. and Hashemi, M. J.}, title = {Evaluation of Energy-Based Modal Pushover Analysis in Reinforced Concrete Frames with Elevation Irregularity}, journal = {Scientia Iranica}, volume = {17}, number = {2}, pages = {-}, year = {2010}, publisher = {Sharif University of Technology}, issn = {1026-3098}, eissn = {2345-3605}, doi = {}, abstract = {In nonlinear static (pushover) methods of analysis as an alternative to time history analysis, the capacity curve of the structure is established with respect to the roof displacement. Disproportionate increases in the roof displacement and even outright reversals of the higher modes can distort the capacity curve of the equivalent single degree of freedom system in these kinds of method, including MPA. To overcome this problem, recently, Energy-Based" the Modal Pushover Analysis (Energy-Based MPA) method has been introduced. In this method, the absorbed energy and/or the external work in the pushover analysis is considered. Accordingly, the assessment of the Energy-Based MPA method is important in the seismic analysis of asymmetrical and tall buildings. In this paper, the seismic demands of concrete structures with irregularity in elevation are determined, using Energy-Based MPA. For assessment of the presented technique, the results are compared with those from the Non-Linear Time History Analysis (NL-THA). Seven examples including a 2-D simulation of a 12-story building are modeled, using the Opensees Code. For each case, di erent types of irregularity, such as mass, geometry and variations due to the di erence in elevation are considered. Story-drifts and oor-displacements are used as the main parameters for assessment of the results. Based on a study of the structural performance of the models, it has been made clear that di erent types of the above-mentioned irregularity in elevation do not have any signi cant e ect on the Energy-Based MPA method. Consequently, this method can be considered as an accurate alternative technique for NL-THA, to fairly estimate the seismic demands of structures.}, keywords = {Energy-Based MPA,Time history analysis,Elevation irregularity}, url = {https://scientiairanica.sharif.edu/article_3129.html}, eprint = {https://scientiairanica.sharif.edu/article_3129_f975971c8b804a644a54659966c9b92c.pdf} }