Review article

In order to reduce the volume of calculation operations, a reverse course of the study of the strength and stability of the rod elements of steel structures in the general case of loading is proposed. For a given limit state in the cross section of the elastic rod element corresponding to the ultimate strain , using the elastic solution method and the «Section» algorithm, the real ultimate state in strength is established. The results obtained in this way are more reliable, since the development of plastic deformations (and for thin-walled elements - section reductions), are determined by the combined action of efforts. The stability of rod elements is known to be characterized by a violation of the equilibrium deformed state. Therefore, following the solutions of the strength problems, at the same loads, a number of stress states are considered in the most loaded section with various values ( ),according to which the «deformation» forces and the corresponding working cross-sectional area and the rod stiffness are determined. Using the latter, the inverse analytical solution of deformation problems determines the largest general loading parameter corresponding to the buckling coefficient.