The stability design checks according to EN 1993‑1‑1, 6.3, are not included in RSECTION 1.
According to EN 1993‑1‑1, 5.2.2 (7) a), the stability analysis may be performed as a cross-section design, provided that a spatial calculation according to the second-order analysis is performed while applying global and local imperfections. In order to model the lateral-torsional buckling, it is necessary to determine the internal forces according to the geometrically nonlinear torsional buckling analysis with regard to warping torsion. It is only necessary to perform the section design, as all stability effects are covered by the calculation.
In RSECTION 1, you can calculate the stresses due to the axial force, biaxial bending moments and shear forces, primary and secondary torsional moment, as well as warping bimoment for any cross-section shape. This way, you can use the design method described in EN 1993‑1‑1, 5.2.2 (7) a) in RSECTION 1.
Furthermore, the Effective Sections add-on (extension for RSECTION 1) allows you to perform a classification according to EN 1993-1-1 and calculate the effective cross-section according to EN 1993-1-5.