Comparative Analysis of Code-Based Dynamic Column Removal and Impact-Induced Progressive Collapse in Steel Moment-Resisting Frames

Civil structures are subjected to accidental or intentional impacts, which can lead to an initial failure, and subsequently to a tragic progressive collapse. While progressive collapse studies have seen significant growth, most of the current research focuses on threat-independent approaches, neglecting the explicit consideration of impact effects on the building's behavior. In this study, we investigate impact-induced progressive collapse, exploring various scenarios with different mass and velocity parameters. By doing so, this study aims to highlight the importance of explicitly accounting for impacts in progressive collapse analyses and provide possible solutions for safer structural design. For comparison, code-based dynamic column removal analyses are also performed and the results are compared and contrasted. Based on the obtained results, location of the damage and height of the building have important influence on the progressive collapse response in both threat-independent and threat-dependent approaches. Velocity plays a significant and critical role compared to mass in increasing the kinetic energy applied to the building, and the vertical vibration in the node on top of the impacted column. With the lower impactor velocities, the threat-independent method can be used safely, however, for the higher velocities the progressive collapse potential is much higher in threat-dependent approach compared with code-based dynamic column removal.