Plastic collapse of metallic conical frusta of large semi-apical angles

Experiments were conducted wherein aluminium conical frusta of different semi-apical angles varying over a wide range from 16.5° to 65° and different slenderness ratios (t/d), were subjected to axial compression. Their various modes of collapse, load-deformation and energy-compression behaviour, and initial peak and mean collapse loads are studied from the experiments. Typical results are presented. An analytical model is proposed for the prediction of load-deformation and energy-compression curves. The influence of semi-apical angle and the slenderness ratio of the conical frusta on the modes of collapse and load-deformation curves is discussed. The results predicted from the proposed analytical model are found to match well with the experiments.