Instability load evaluation of shallow imperfection-sensitive structures by form and interaction parameters

In terms of the interaction between buckling and snap-through for shallow structures affected by geometrical imperfections results have shown that, after the nonlinear bifurcation, load reductions occurs accompanied with a predictable tendency. In order to do it, the tracing of interaction domains and interaction curves presented in recent papers by the same Authors, has been proposed. In this study, every simple structural arrangement has been analyzed with regards to different shallowness ratios, slenderness, restraining conditions and imperfection patterns. It has been observed how the driving parameters could be led back to two original interaction (Delta) and form (Omega) factors. This procedure could shed new light on the application of the more burdensome imperfection pattern for the instability of geometrically nonlinear structures. Possible implications of these results have been presented, with a special attention to sensors and structural identification. The study accomplished numerous numerical simulations and showed good agreement with the theoretical expected results. (C) 2017 Elsevier Masson SAS. All rights reserved.