Buckling study of single-stepped columns subjected to both intermediate and end axial loads are introduced in this paper. The column understudy is considered as two segments where the upper and the lower parts have different cross-section moment of inertia or different material and subjected to an intermediate load at the location of the cross-section change beside the end load. All the classical end conditions of the studied column are considered in this paper as pinned ends, clamped ends, clamped-free ends and clamped-pinned ends. The analysis is developed using the finite element method to study the effect of the different parameters in the buckling loads. These parameters are i) ratio of the intermediate axial load to the end axial load, ii) the intermediate load location as a ratio to the column span and, iii) the ratio of flexural rigidity of lower segment to that of the upper one. The obtained numerical results are introduced in many interaction curves to obtain the buckling loads for each end conditions considering the other parameters.
A comparison between the obtained results and that of the available theoretical studies shows the accuracy and the simplicity of the present work to get the critical load.