Ultimate strength of stiffened aluminium plates

摘要

An experimental and numerical investigation is carried out to study the buckling behaviour of aluminium plates with longitudinal stiffeners subjected to axial compression. The test specimens, 2000 mm long, are built up with extruded aluminium profiles connected with welding. Two types of stiffened plates are investigated; one with open section (L shape) stiffeners and the other with closed stiffeners, both in aluminium alloy AA6082 temper T6. The experimental programme comprises tests on plates supported along all four edges, and as a special case plates supported at two edges only ("column behaviour"). All details, such as cross-sectional geometry, material properties and measured initial imperfections, are given, and the experimental results are shown by means of response curves. Numerical simulations of the tests are carried out using the finite element code ABAQUS. It is found that the finite element simulations predict quite accurately the behaviour and the resistance of the stiffened aluminium plates, both for the observed global buckling and the stiffener tripping (for the L shaped stiffeners only). The experimental results are also compared with the resistance calculated from the design rules in ENV 1999-1-1 (EC 9) for aluminium structures. In all experiments the measured maximum load exceeds the EC 9 design resistance.