Flexural–torsional buckling of open section composite columns with shear deformation

The paper presents the stability analysis of axially loaded, thin-walled open section, orthotropic composite columns. Vlasovʹs classical theory is modified to include both the transverse (flexural) shear and the restrained warping induced shear deformations. In addition to the bending stiffness matrix a (3×3) shear stiffness matrix is introduced. A closed form solution is derived for the flexural–torsional buckling load of composite columns. A simplified, approximate solution is also presented, in which the effect of the shear deformations is included using Föpplʹs theorem.