A two-scale method to include essential screw connection behaviour in two-way coupled fire-structure simulations

Purpose Simulations exist for the prediction of behaviour building structural systems under fire, including two-way coupled fire-structure interaction. However, these simulations do not include detailed models connections, whereas connections may impact overall structure. Therefore, this paper proposes a two-scale method to screw connections. Design/methodology/approach The consists (a) global-scale model that system and (b) small-scale describe connection. Components in are connected by spring element instead modelled screw, stiffness is predicted model, updated at each load step. For computational efficiency, uses proprietary technique threads, verified complete thread geometry, validated existing pull-out experiments. four failure modes, load-deformation predictions model. Additionally, combined case experiments, demonstrated different temperatures. Finally, illustrated as part simulation. Findings It was shown ”threaded connection interaction” can predict relevant i.e. failure, shank tension pull-out. bearing, shear, tension, correspond with Eurocode predictions. Related cases, variety experiments good correlation has been found between experimental simulation results, however, were be inconsistent. Research limitations/implications More research needed before used all conditions. This relates criteria pull-out, temperature loads. Originality/value bridges very present models, best only use springs. shows insightful, it contains functional separation scales, revealing their relationships, computationally efficient allows distributed computing. Furthermore, local non-convergence (e.g. failing) handled without convergence problems