Druck- und biegebeanspruchte Stäbe mit dünnwandigem Hohlkastenquerschnitt - Tragverhalten und Tragreserven gegenüber Eurocode 3

Beam columns with thin walled boxed sections - Load bearing behaviour and increased loading capacity compared with Eurocode 3.

Beam columns with box sections, especially if fabricated from plates made of high strength steels, often lead to slender elements with class 4 cross-sections, i. e. sections that are susceptible to local buckling. The presented comprehensive study compares the load bearing capacity, based on nonlinear FEM-models, with the predictions of Eurocode 3. The definitions of local imperfections in Eurocode EN 1993-1-5 are presented and discussed. The detected, significantly increased loading capacity of columns with fixed ends and antisymmetric moment distributions is an indication that, even for class 4 sections, a hinged-truss model may be used in the global analysis with sufficient safety. This is shown for the design of members of a single-span truss girder by means of a numerical example.