Appropriateness of current regulatory requirements for ensuring the robustness of precast concrete building typologies

The phenomenon of progressive collapse can be likened to the failure of a house of cards where structural damage propagates beyond the locality of the initial damage and to an extent disproportional to the original cause. Insufficient consideration of the structure’s potential for progressive collapse has widely been seen as responsible for some of the most high profile structural collapses of the last 60 years. The need to rigorously consider and mitigate for the risk of such collapse occurring is often seen to be more imperative within the design and detailing of pre-cast concrete structures, which is mainly due to their segmental nature of and associated inherent lack of structural continuity. Aimed at highlighting the need for a more quantitative design methodology, the paper evaluates the suitability of commonly advocated measures for ensuring structural robustness in pre-cast building typologies. Using a non-linear ‘push-down’ simulation the suitability of existing tying and anchorage force provisions are evaluated, with such prescriptive detailing rules often adopted by design engineers to justify a suitable level of structural robustness. This computational assessment enabled a quantitative assessment of the performance of pre-cast framed buildings subjected to a sudden column loss event. The findings highlight a need for current design and detailing practice to take more appropriate account of the nonlinear response of components and joints incorporated within multi-storey buildings.