Design of stiffening rings for a steel tank shell. The amendment of the standard formula

<ns3:p>The method of designing stiffening rings of a steel tank shell is specified in the rules included in Eurocode EN 1993-4-2 in force since 2007 and in its national version of 2009. A reservation regarding the correctness of one of the formulae was raised in 2015 by Prof. Aleksander Kozłowski. The amendment of the disputed formula was adopted by the CEN/TC 250/SC 3/WG 16 working group developing the second generation of Eurocode EN 1993-4-2, which will enter into force in 2027. The paper presents the scientific basis of the rules contained in the standard and the history of Prof. Kozłowski’s effective intervention</ns3:p>