Toughness-dependent net-section resistance and ductility behaviour of high-strength structural steels S700 to S960

Structural steels with higher strengths enable slender and material saving, thus particularly sustainable construction. According to the second generation of EN 1993-1-1, which is to be applied in the future, design of steel structures is already possible up to steel grade S700. However, already now, the standardization committee CEN/TC/250/SC3 has commissioned the respective WG12 to prepare rule proposals for the Eurocode for the design of steel structures using steel grades in the range S700 to S960. Clarification of the material requirements in this context is at the very beginning of the works. The question arises as to whether the set of requirements as formulated so far for steels up to S700 can continue to exist not only in the amount of minimum or limit-values, but also whether the type of requirements would then still be appropriate. This paper reports on component-scale experimental investigations on several high-strength steels S700 to S960 (HSS) with special focus on the dependence of the load-bearing behaviour and the ductility properties on the varying material toughness at different temperatures. For the lower-shelf, the results can be compared with the current design approach to avoid brittle failure according to EN 1993-1-10, while the experimental investigations also can be evaluated with regard to a possible upper-shelf toughness criterion to ensure ductile behaviour.