XAVIER, F.B.1; MACORINI, L.2; IZZUDDIN, B.A.3

1) PhD candidate, Imperial College London, Department of Civil & Environmental Engineering, francisco.xavier11@imperial.ac.uk

2) Lecturer, Imperial College London, Department of Civil & Environmental Engineering, l.macorini@imperial.ac.uk

3) Professor of Computational Structural Mechanics, Imperial College London, Department of Civil & Environmental Engineering, b.izzuddin@imperial.ac.uk

The influence of non-structural unreinforced masonry infill panels on building structural performance under extreme loading conditions is not yet fully understood. In this paper, the potential contribution of masonry infill towards arresting progressive collapse in steel-concrete composite frames is investigated within the robustness assessment methodology developed at Imperial College London. An accurate panel description is achieved employing a mesoscale modelling scheme capturing any geometrical layout. The simulation strategy is further enhanced by nonlinear beam-to-column joint mechanical modelling and a detailed description of frame/infill interaction. These are included in a partitioned multi-dimensional framework suitable for parallel computing. It is observed that masonry infill panels, whether solid or perforated, provide effective load redistribution paths under sudden column loss in peripheral bays, resulting in increased progressive collapse resistance. Notwithstanding, it is also established that detrimental effects might also arise due to excessive forces at joint level, highlighting the importance of properly capturing frame/infill interaction.

Keywords: Mesoscale Model, Infilled Frame, Progressive Collapse, Design-Oriented Robustness Assessment