Unconstrained Vector Positional Shell FEM formulation applied to thin-walled members instability analysis

摘要: Abstract In this study, for the first time, we present a shell finite element based on positions and generalized vectors instability analysis of thin-walled members. The presence transverse strain enhancement guarantee to proposed formulation good representation stress fields inside element, allowing use complete three-dimensional constitutive law without any locking. is total Lagrangian naturally covers large displacement modeling. past studies, limited connection portions or non-tangential panels, making it difficult model To solve problem, strategy ensure between non-coplanar elements, considering stiffness connecting material, originally developed presented in paper. numerical examples explore differences among buckling load achieved using small displacements limit points (or bifurcation points) displacements. influence sensitivity are also tested when comparing these values. Results validated against literature reference values new show applicability positional formulation.