Failure progression resistance of a generic steel moment-resisting frame under beam-removal scenarios

Purpose - The purpose of this paper is to determine the failure progression resistance of the steel moment-resisting frames subjected to various beam-removal scenarios after application of the design earthquake pertinent to the structure by investigating a generic eight-story building. Design/methodology/approach - The structure is first pushed to arrive at a target roof displacement corresponding to life safety level of performance. To simulate the post-earthquake beam-removal scenario, one of the beam elements is suddenly removed from the structure at a number of different positions. The structural response is then evaluated by using nonlinear static and dynamic analyses. Findings - The results show that while no failure is observed in all of the scenarios, the vulnerability of the upper stories is much greater than that of the lower stories. In the next step, the structural resistance to such scenarios is determined. The results confirm that for the case study structure, at most, the resistance to failure progression in upper stories is 58 percent more than that of lower stories. Originality/value - Failure and fracture of beam-to-column connections resulting in removal of beam elements may lead to a chain of subsequent failures in other structural members and eventually lead to progressive collapse in some cases. Deficiency in design or construction process of structures when combined by application of seismic loads may lead to such an event