Non-linear global stability analysis of thin-walled laminated beam-type structures

• Stability analysis of laminated composite thin-walled beam structures.
• The equilibrium equations of a FE are formulated using the virtual work principle.
• Analysis is performed in load deflection manner using corotational formulation.
• The model takes into account the viscoelastic behaviour of composites.
• Implementation of developed algorithm is validated through test examples.

The paper presents an algorithm for buckling analysis of thin-walled laminated composite beam-type structures. One-dimensional finite element is employed under the assumptions of large displacements, large rotation effects but small strains. The equilibrium equations of a prismatic and straight spatial beam element are formulated using the virtual work principle. Stability analysis is performed in load deflection manner using corotational formulation. The cross-section mid-line contour is assumed to remain not deformed in its own plane, whereas the shear strains of middle surface are neglected. Laminates are modelled on the basis of classical lamination theory. Results have been validated on test examples.