Buckling analysis of homogeneous or composite I-beams using a 1D refined beam theory built on Saint Venant's solution

Linear buckling of homogeneous or composite I-beams are investigated using a refined beam theory built on 3D Saint-Venant's solution. The kinematic model includes sectional Poisson's effects and out-of plane warpings extracted from 3D Saint-Venant's solution and distortions related to the free vibrational behaviour of the cross-section. Available for an arbitrary cross-section and free from the classical beam and shell-like assumptions, such displacement model leads to a consistent 1D beam theory which really matches the cross-section nature (shape and materials). Moreover, in order to easily apply this method, a user friendly numerical tool has been developed. To show the capabilities and the accuracy of the proposed model to deal with thin-to-thick walled beams, homogeneous and laminated I-beam configurations subjected to axial or transversal loads are performed. The numerical results are compared to literature and some of them to 3D-FEM solid model.