A simplified design-oriented approach for the assessment of robustness and progressive collapse has been developed recently at Imperial College London. In the simplified assessment framework, sudden removal of a vertical member has been identified as an event-independent scenario that can be used for the assessment of structural robustness. This paper aims at establishing whether the assumption of sudden column loss is realistic, and whether it provides a meaningful assessment in relation to actual extreme events, where particular focus is placed on blast events. By comparing the resulting deformations in the upper structure to those achieved under sudden column loss, a relationship is established between the effects of actual blast events and the effect of idealised sudden column loss. In this respect, it is shown that sudden column loss is indeed a very useful design scenario for the assessment of structural robustness, benefitting from event-independence, yet offering an upper bound on the deformation demands as a result of blast events.
G. V. GudmundssonStructural Engineer, Flint & Neill Partnership, London
B. A. IzzuddinProfessor of Computational Structural Mechanics, Department of Civil and Environmental Engineering, Imperial College London