International Institute of Earthquake Engineering and Seismology Journal of Seismology and Earthquake Engineering 1735-1669 19 2 2017 04 01 Estimating the Loading Pattern Factor of Modal Pushover Analysis (MPA) for Integrated Bridges Using IDA Responses 163 169 240761 10.48303/jsee.2017.240761 EN Yaser Nasiri Islamic Azad University, Science and Research Branch, Tehran Panam Zarfam Islamic Azad University, Science and Research Branch, Tehran Journal Article 2016 05 16 In this paper, a new applied relationship is introduced for the analysis of integrated bridges where no expansion joint embedded on the deck. It can be used to investigate the seismic behavior and actual performance of integrated bridges under earthquake force and, in spite of its simplicity, its accuracy is acceptable. In fact, this relationship can be considered as a combination of incremental dynamic analysis and modal pushover analysis, benefiting from the advantages of both approaches, i.e. an appropriate loading pattern factor of Modal Pushover Analysis can be obtained by using Incremental Dynamic approach. To this end, the average acceleration - displacement and average acceleration - shear base of 120 earthquake records applied on the bridge are calculated and then the obtained incremental dynamic curve is plotted in the coordinates of displacement and shear base. For the obtained modal pushover curve, the sum of the first three SRSS modes is selected. The literature shows no record of the study conducted on the comparison of the two curves. In this paper, the aforementioned comparison was made using Incremental Dynamic Approach through examining six regular and irregular integrated bridges and applying 120 earthquake records in 10 acceleration levels. It was observed that the accuracy of the proposed relationship in predicting the bridge displacements and shear forces of columns' piers was high, and the calculation output showed negligible differences with dynamic analyze results. In this study, the soil-structure interaction is ignored. https://www.jsee.ir/article_240761_0c5caa1243365ac995cffd5a9f0ac0d5.pdf