عنوان مقاله [English]
The earthquake duration has a significant effect on the amount of destruction of structures. Some samples of The earthquake duration has a significant effect on the amount of destruction of structures. Therefore, it is important to study seismic sources that can produce earthquakes with a long duration in Iran, and the effects of long duration on structures should be considered at the design time. This problem is not just due to a long duration earthquake, but also some large aftershocks can make destruction. In this article, the performance of concrete structures affected by different durations is studied and the effects of stiffness degradation and strength loss of the structural members under cyclic movements of the earthquake are assessed. For this purpose, three concrete buildings like 3, 9 and 15 stories have been modeled by finite element software Seismostruct 2016 modeling and have been affected by energy scaled records and same soil conditions. These records are different in terms of effective duration to can study the behavior of the structure in different durations.The results of non-linear time history analysis of the structure under mentioned records indicate that the number of plastic hinges and maximum displacement caused by earthquakes with a long duration is much higher than those with low duration. Also, the study of the behavior of buildings under earthquakes with different duration shows that earthquakes should not be arranged according to their apparent durations. The number of cycles of the earthquake with high accelerations to a certain limit increases, the more effects on structures is increased.