Towards a stability verification of two‐span members based on experimental and numerical investigations

State‐of‐the‐art stability design methods of the current and future Eurocode 3 are based on idealized, simply supported members with fork restraints. However, in real‐world structural engineering applications, continuous members or frame structures are more common. The verification of these members often requires complex geometrically nonlinear computations. This paper addresses the extension of simplified methods to structural systems. The basis is laid with experimental, numerical and analytical studies on the stability behavior of two‐span members with doubly symmetric I‐sections in bending, axial compression and torsion. Five‐point bending tests were conducted to analyze the buckling behavior of two‐span members. The experimental results validate a numerical model subsequently used to extend the data basis. A comparison of the numerical load capacities with the results of the simplified method for the buckling resistance according to Annex C.2 of EN 1993‐1‐1:2022 reveals the method's applicability. The sensitivity analysis of the method to various parameters identifies potential for improvement concerning the capture of the influence of bending moments about the weak axis and warping moments, as well as the influence of lateral‐torsional buckling for stocky members.