Large rotation analysis of elastic thin-walled beam-type structures using ESA approach

In this work a non-linear analysis of beam-type structures with a thin-walled cross-section is presented. Using updated Lagrangian formulation and the non-linear displacement field of asymmetric cross-section accounting for large rotation effects, the incremental equilibrium equations of a beam element are obtained. Material is assumed to be isotropic and linear elastic. Obtained geometric potential of internal moments corresponds to semitangential behaviour providing the joint equilibrium of non-collinear elements. External stiffness approach is applied in the force recovery phase by introducing the external stiffness matrix. The accuracy of presented finite element algorithm is validated through the test problems.