Limitations of Current Robustness Standards in Steel‐Composite Buildings

Abstract Current design standards emphasize structural continuity to achieve resilient, safe, efficient and durable building structures. Incidents such as the collapse of the Plasco Building (2017, Iran) and the partial collapse of the Ministry of Foreign Affairs Building (2024, New Zealand) highlight how extraordinary events can cause failure of a steel‐composite building, making it unsafe. Various methods aim to enhance the robustness of steel structures against extreme events or local‐initial failures. Prescriptive tying rules improve continuity by introducing a minimum number of continuous ties. The alternative load path method explicitly verifies load redistribution after an initial component failure. These methods rely on structural continuity to manage load redistribution and maintain stability after small initial failures. However, in larger failure scenarios, they can contribute to complete collapse. This study examines a steel‐composite building (7x3‐bays, 10‐meter spans, three storeys) designed by Eurocodes for common loads, wind, seismic and accidental actions. The goal is to assess the limitations of continuity‐based methods and the risk of propagating an initial failure. Results aim to inform future standards to improve designs and mitigate major structural failures.