Progressive Collapse of Steel-Framed Structures

Progressive collapse is the phenomena in which the local failure of a primary structural member results in partial or total structural system damage, without any proportionality between the initial and final failure. In the present study, multi-story structure is considered. The modeling and analysis are carried out using SAP2000 software. The different bracing systems such as X, V, K and diagonal bracing are used to analysis the structural behavior. The structure is verified for column removal at 3 different locations such as corner, center and interior. It is observed that maximum vertical deflection is found in interior column removal case and least in corner column removal. Interior column case was observed to be most critical case in progressive collapse. There is a raise in axial load and the load distribution to the adjacent columns for column removal at location 1, 2, 3 is around 30%, 25%, and 20%, respectively. The X bracing system performs well in case of progressive collapse.