A simplified approach for modelling failure propagation of steel structures

Abstract

[EN] Assessing the likelihood of progressive collapse in buildings resulting from the local failure of individual structural elements is challenging, especially in steel buildings. Engineers invest significant effort in modelling various connections between structural members, requiring detailed 3D solid elements. The complexity and computation time increase exponentially when analysing an entire building instead of local subassemblies. This study presents a practical methodology for modelling steel structures to predict progressive collapse rapidly. It adopts the distributed plastic hinges approach and is able to accurately simulate large deformations expected in collapse scenarios. Suitable experimental tests were selected to validate the proposed methodology, revealing the sensitivity of predictions to modelling assumptions such as the positioning of the hinges, the plastic length of each hinge, the cross-section discretisation, and the material definition. Finally, a set of recommendations for the simplified modelling of steel structures is provided for practising engineers working in the progressive collapse domain.