Plastic collapse of hardening spatial aluminium frames: A novel shakedown-based approach

In the present work a novel approach is proposed for determining the safety factor of spatial aluminium frame structures against elastoplastic collapse. For the purposes of the study, a two-surface shakedown-based technique is developed, exploiting material's hardening features, tailored to the stress resultant plasticity discipline using linearized forms of codified criteria. This way, the classical advantages of direct methods of plasticity, such as robustness, mono-parametric safety assessment and load history independence are also enabled in the field of aluminium plastic design. Results demonstrate the effectiveness of the applied technique, providing a reliable alternative path for analysing inelastic performance of aluminium structures.