About the Project
Key to the resilience of steel-framed buildings under any form of extreme load is a robust and ductile structural frame, especially at the joints. These are required to undergo considerable inelastic rotations and accommodate high tying forces at large deflections during an extreme event, thus allowing beams to develop catenary action and provide alternative load paths in the case of a sudden column loss.
This project will study experimentally and numerically the strength and available ductility of steel joints subjected to extreme loading cases and generate alternative designs with improved response by utilising highly ductile stainless steel for the critical components of the connections. Extensive material characterisation studies on both carbon and stainless steel material under static and high strain rates will be undertaken to allow material fracture to be simulated. Thereafter, lap joints, T-stubs, bolted connections and subframes under a column loss scenario will be tested under both static and high strain rate loading consistent with the strain rates occurring during progressive collapse. Higher strain rates consistent with impact loading will also be considered. Numerical models will be developed and validated against the obtained test data and parametric studies will be conducted to study the influence of key parameters such as adopted material, bolt arrangement, end plate/angle cleat thickness and level of beam axial restrain, on the structural response of joints under extreme loading. Based on the obtained results, design recommendations will be developed that will lead to the enhancement of the overall structural robustness via optimising the joint design.
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