Probabilistic assessment of the impact of straightness tolerances in en 1090-2 on the stability design of steel columns


  • Andreas Taras


buckling, imperfections, tolerances, structural reliability, eurocode 3, probabilistic assessment, steel columns


This paper addresses a current, practical topic which has interesting implications for design practices and research in the steel construction industry: the impact of new, relaxed fabrication tolerances on the strength of compression members. The current debate on this topic – held at a code committee level – was triggered by the introduction of increased tolerances for the out-of-straightness of steel members in the new European standard for the execution of steel structures for constructional steelwork, EN 1090-2 [1]. The extent to which these changes are still “covered” by the present design rules is currently unknown. To date, a consistent, logically coherent justification for the acceptance of these changes is still missing. The study presented in this paper is therefore intended as a contribution to this debate. In the broader scientific context, it is intended to serve as an example for the possibility of answering questions regarding the impact of changes to production tolerances and manufacturing habits on design rules by probabilistic approaches.


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