Global buckling analysis model for thin-walled composite laminated beam type structures

This paper presents a beam finite element model for non-linear global buckling analysis of composite laminated beam type structures. To perform the non-linear stability analysis, the framework of updated Lagrangian incremental formulation is used. The non-linear displacement field of thin-walled cross-section is adopted in order to insure the geometric potential of semitangential type for both the internal torsion and bending moments. The cross-section mid-line contour is assumed to remain not deformed in its own plane and the shear strains of middle surface are neglected. The laminates are modeled on the basis of classical lamination theory. In order to illustrate the application of the proposed formulation, several numerical examples are presented. For validation purposes, the obtained results are compared with results reported in the literature and the ones obtained with shell finite elements by Nastran.