Dynamic Analysis of Steel Shear Walls Using Different Spectrums in Near and Far Fields

Recently steel shear walls have been considered as a resistant system against lateral loads. Also researchers have seen different effects of earthquakes of near and far from the fault. These researches shows that mappings of near fault have less effective time than mappings of far from the fault and have one or more special pulse, large domain and medium to large frequency which causes to increase the domain of response spectrum in large period zones. In this article four moment resisting steel frames each of which has four spans 3, 7, 15 and 25 stories that only their mid span has steel shear wall with thin plate (strip model) have been analyzed under near or far from the fault and Iranian Earthquake 2800 Code spectrums. By the assumption of well acting of strip model, results showed that base shearing and relative roof displacements of 3 and 7 stories under the near fault spectrum was 2 to 32 percent less than the cases under far from the fault and Iranian Earthquake 2800 Code spectrums and at 15 and 25 stories the consequence was vice versa and averagely 22 and 52 percent more than the amounts of far from the fault and Iranian Earthquake 2800 Code spectrums.