Analyse non lineaire en grandes rotations et grands deplacements des structures minces metalliques (French text)

An engineering aided-tool for structural computations has been developed and proposed. This tool allows the complete (total) numerical simulation of the nonlinear behavior (geometrical and material nonlinearities) of metallic structures, taking into account their imperfections (residual stresses and deformations). This report presents the strategy and the models associated with the proposed tool. Herein are presented promising algorithms and techniques for nonlinear computations of structures subjected to large displacements and large rotations. The kinematic of finite and differential rotations are (re)developed with the concern of easier understanding by structural engineers. The formulation and then the validation of 3D beam and shell models, based on the so-called “exact” kinematics, are also presented. In order to illustrate the practical features of the proposed tool, two industrial applications are considered. The first one consists of studying the post-critic resistance of an ondulated panel. The second one concerns the simulation of ROPS (Roll-Over Protective Structure) test of a ranger truck taking into account residual stresses and deformations. The results are very satisfying and shows the robustness of the developed software.