Abstract
This paper presents a finite element method which enables to analyze a large displacement behavior of elasto-plastic thin-walled structures which fail by overall, local or interactive instability. An incremental equilibrium equation for a thin-walled beam-column is derived in a stiffness matrix form by using a moving element coordinate system and an incremental variational principle. So called multipoint constraints technique is used to connect plate elements with a beam element at the coupling nodal point in the cross section. Numerical results of the present method are compared with the exact solutions and experimental results. Validity and efficiency of the present method are confirmed.
