Breaking continuity to prevent catastrophic building collapse

It is increasingly difficult to predict all the hazards that buildings will face over their lifetime, highlighting the need to design robust structures that can tolerate unforeseen damage. Typically, robustness is pursued by providing continuity within a structural system. While this strategy performs well in expected scenarios, it increases the risk of catastrophic collapse propagation when initial damage is large. Using high-fidelity simulations, we first identified and characterised the key mechanisms responsible for continuity-enabled collapse propagation in highly continuous building structures such as those made of cast-in-place reinforced concrete. Building on this understanding, we developed: 1) a design approach that employs bespoke force-regulating fuses to interrupt continuity when it becomes detrimental, and 2) an experimental setup that allows system-level collapse propagation to be evaluated by testing only a representative part of a building. Overall, our work shows that continuity can be selectively disengaged even in intrinsically continuous structures and provides a cost-effective way of testing the next generation of solutions against unforeseen extreme events.