Evaluation of Eccentrically Braced Steel Frames with Double Vertical Link Beam under Progressive Collapse

In this article, the performance of Eccentrically Braced Frames with Vertical Shear Links against progressive collapse has been investigated based on GSA guidelines and the alternative path method. For this purpose, three frames of 5, 10, and 15 floors have been investigated, and their performance was estimated by the method of nonlinear dynamic analysis with SAP2000 software. By removing the middle column for all three frames, it was observed that the displacements are regular and perform well in progressive collapse. However, with the removal of the corner column, the five-story frame collapsed, and for the 10-story frame, an increase of about 3 times the floor displacement was observed. But for the 15-story frame, the behavior of the frame under progressive collapse is very suitable. The removal of the corner column in the frames creates a more critical condition than the removal of the middle column. In the scenario of removing the middle column, the maximum vertical displacement on the last floor of the 5-story frame was equal to 9.21cm, in the 10-story frame it was equal to 6.37cm and in the 15-story frame, it was equal to 4.25cm. For comparison, in the scenario of removing the corner column, the maximum vertical displacement obtained on the last floor of the 5-story frame was unknown due to collapse, and in the 10-story frame it was equal to 21.88cm and in the 15-story frame, it was equal to 7.65cm. Results show that as structure height