Non-linear idealisation error analysis of a metallic stiffened panel loaded in compression

The SAFESA procedure is an idealisation error control process developed for linear static finite element (FE) analysis. This paper investigates the application of this process to non-linear FE in order to provide an equivalent methodology valid for non-linear problems. The post-bucked collapse of a stiffened panel in compression is used as the case study for this investigation. The main part of the paper presents the critical analysis of important modelling assumptions, including the material model, the panel to stiffener contact, boundary conditions and geometrical imperfections. Several potential idealisation error sources are identified using the process and then investigated using the non-linear FE code ABAQUS. The outcome of the analysis is an improved FE model and a quantification of the idealisation error, showing that the idealisation error control process can be applied to non-linear analysis