New design curves for LT and TF buckling with consistent derivation and code-conform formulation

Whereas the European column buckling curves are generally well accepted, the buckling curves given in Eurocode 3-1-1 for lateral-torsional (LT) and torsional-flexural (TF) buckling are still under discussion. This situation stems from the fact that the latter have not been developed with the same broad consensus as the column buckling curves, but had to be provided for the publication of the Eurocode in a rather short time. In the meantime, further research has achieved, on the one hand, a much deeper understanding of the mechanical behaviour and, on the other, a better approach for an appropriate design formulation for member buckling cases in conformity with the code. This paper reports on current developments in new design LT and TF buckling curves that are fully consistent with the background and methodology of the European column buckling curves.