Step 1: Pre-analysis

We must first calculate the theoretical critical buckling load of the column.   
Where:

F = maximum or critical force (vertical load on column),

E = modulus of elasticity,

I = area moment of inertia,

L = unsupported length of column,

K = column effective length factor, whose value depends on the conditions of end support of the column, as follows.

For both ends pinned (hinged, free to rotate), K = 1.0.

For both ends fixed, K = 0.50.

For one end fixed and the other end pinned, K = 0.699....

For one end fixed and the other end free to move laterally, K = 2.0.

KL is the effective length of the column.

For a circular cross section, 
Therefore, for our problem, I = .003068

Therefore, our critical buckling load is = 1.51398E+7 N

Go to Step 2: Geometry
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