Consider a universal column 203mm x 203mm x 46.1 kg/m with a flange thickness of 11mm and web thickness of 7.2mm. The height of the column is 10m and has load applied on to a pinned joint on top and is fixed in concrete at its base. Calculate the load necessary to induce the column to buckle.
The calculated buckling load is 636 kN
Now we can compare this to the FEA model. The beam was constructed with brick elements and fixed at the base with a constraint and load at the top.
The eigenvalue for mode 1 is 631.66. To find the load that will cause the column to buckle you just multiply the applied load by the eigenvalue.
Since 1000 N or 1 KN was applied to the model this means that the buckling load is 631.66 KN.
The hand calculated buckling load was 636 KN and the FEA buckling load was 632 KN.