Assessing the Performance of Steel Bundled-tube Rigid Frames under Records Scaled Based on the Third and Fourth Editions of The Iranian seismic code 2800

This research studies the performance of medium to high-rise steel bundled-tube rigid frames under scaled far and near field earthquake records according to the third and fourth editions of the Iranian seismic code 2800. The results are achieved and assessed based on nonlinear time history analyses subjected to a selection of three-component records. A part of the mentioned selection includes two earthquake records in Iran in Tabas 1978 and in Bam 2003, also two powerful pulse type records of the Northridge 1994 earthquake. Yet, the second part includes one far field record of the Northridge 1994 earthquake. The studied structure models are bundled tubes designed according to the Iran Seismic code 2800 (fourth edition) in two heights of 10 and 20 stories. The results of this study show that by using the version 2800-4, the scale factors followed by the responses of the studied structures under records scaled with these factors decrease compared to their corresponding cases calculated based on the version 2800-3.

Keywords:

seismic design , near field record , velocity pulse , scale factor , bundled-tube rigid frame