Lateral buckling of thin-walled composite bisymmetric beams with prebuckling and shear deformation

The effects of the in-plane prebuckling deformations as well as the effect of shear flexibility on the lateral buckling of bisymmetric thin-walled composite beams has been investigated in this paper. The analysis is based on a geometrically non-linear theory based on large displacements and rotations. The Ritz variational method is used in order to discretize the governing equation and then the buckling loads are obtained by requiring the singularity of the tangential stiffness matrix. The numerical results show that the classical predictions of lateral buckling are inaccurate, and the considered effects should be taken into account for obtaining reliable solutions. Besides, the effects of span length and height of the load point have also been investigated for different laminate stacking sequence.