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(2) Since the deflections, forces and reactions for linear buckling analysis correspond to normalized buckled shape of the structure, you would need to run nonlinear buckling analysis to obtain the actual displacements, forces and reactions for your structure. The screenshot below illustrates output from nonlinear buckling analysis of a column with initial imperfections (that are modeled by lateral load that will cause a lateral deflection of the column this equal to 0.6% of the column height). You will notice a softening of the structure that would indicate an onset of buckling.
The model for which the above plot was obtained can be downloaded from the P-Delta effect for fixed cantilever column test problem page.