Numerical validation of the general method in EC3-1-1 for prismatic members

Part 1-1 of Eurocode 3 includes a general method for lateral and lateral–torsional buckling of structural components that uses a Merchant–Rankine type of empirical interaction expression to uncouple the in-plane effects and the out-of-plane effects. In this paper, the safety of this approach is assessed for prismatic members subjected to compression, bending and bending and axial force by comparison of both with advanced nonlinear numerical simulations (GMNIA) using beam and shell elements and the other Eurocode 3 approaches based on the European buckling curves. Analytical expressions are derived for columns, beams and beam–columns that show the variation of resistance with varying slenderness. A parametric study is carried out whereby cross-sectional shape, type of loading, slenderness and steel grade are varied. It is concluded that the method gives similar levels of safety as the methods prescribed in clauses 6.3.1 to 6.3.3 of Eurocode 3, part 1-1.