Evaluating the nonlinear behavior of steel moment frames under pushover analysis

The used seismographs in design earthquakes must be representative for the real movement of land in construction location at the most. In order to compare the results of time history dynamic analysis and response spectrum analysis or static analysis, it is necessary to scale the required seismographs. In this paper various methods are applied to scale the seismographs and the results are investigated. Based on the results, for the 15-story building, the Iran 2800 code method has the most displacement in stories. Also, the least values are obtained for Kircher method. The Iran‘s 2800 code makes an appropriate safety area for all low, middle and high rise buildings. The maximum drift for 15 story structures has negligible difference in logarithmic and Kircher method which is about 6%. Therefore, in high rise buildings the same as middle structures, these methods present the same results. The difference for the maximum displacement between Iran‘s 2800 code with Kircher and logarithmic methods has 39% and 36% difference. The Iran‘s 2800 code shows the maximum displacement for all the models, since it is an specification and needs to be more conservative. Therefore, this method is not recommended for tall buildings.

کلیدواژه ها:

steel frame ، non linear analysis ، pushover analysis ، scaling