Revision of EN 1993‐1‐1 – Design Rules for Member Buckling

In the framework of the revision of Eurocode 3 Part 1‐1, several amendments have been proposed and accepted in order to improve the rules for the resistance to member buckling. For clarification, a flow‐chart connecting the global analysis (1st or 2nd order), the imperfections and the type of verification has been implemented for ease of use. Since the publication of the standard in 2005, many research projects have been carried out across Europe on this topic and their results have contributed to provide appropriate answers to problems identified in practice. Therefore, the revised code provides new design rules for stability. Important works of calibration have been performed in these different projects to derive appropriate values of the partial factor on the resistance side. For example, a new formulation for lateral torsional buckling has been introduced for the calculation of the reduction factor. The consequence is a reduction of the discrepancy between the results obtained by these new methods and those from experimental or numerical tests. In order to extend the scope of Eurocode 3 Part 1‐1, additional methods have been implemented in an annex to cover the stability of members with mono‐symmetric cross‐section under compression axial force, biaxial bending, with or without torsion. The format of the resistance criteria remains similar to the format of the current interaction formulae so that the designers can easily identify the evolution of the rules. This paper presents in a systematic way the new implementations in prEN 1993‐1‐1.