Buckling Analysis for Members with Variable Rigidity by Using the Finite Element Method

The stability analysis for compressed bars with variable rigidity is studied, by using the finite element method (FEM) in Galerkin’s variant. The general shape of elastic and geometrical stiffness matrices are obtained for stepped and tapered bars. In a study case, the critical buckling load obtained by using FEM, for three columns with constant and variable sectional stiffness (in steps and continuous variation), is evaluated in comparison with others analytical and numerical methods.