Buckling of stiffened panels: an improved linearized approach compared to nonlinear collapse analysis

This paper deals with the buckling assessment of stiffened panels, typical of ship and offshore structures. In particular, rather slender structures, involving very thin plates and stiffeners with limited cross section, are considered. In order to limit the computational burden of a fully nonlinear progressive collapse analysis but, at the same time, to retain some benefits of a numerical finite element model assessment, an improved linearized buckling procedure is proposed in this work. The idea is to linearize the computation in a suitable point based on the design load of the structure, so that the results of a linearized buckling analysis are more informative in practice. Results are assessed with nonlinear collapse analyses, comprehensively considering various loading cases. Eventually, a hands-on buckling assessment procedure is suggested, which can be implemented in rules and design process if adequately validated by a suitable number of test cases and, possibly, experimental data.