The elastic analysis can be done according to a 1st or 2nd order calculation.

- What is the difference between a 1st and 2nd order calculation?
- Do I need a 1st or 2nd order calculation for my structure?

Answer:- If the structure is sway → 2nd order calculation
- If the structure is non-sway → 1st order calculation

- How do I determine if the structure is sway or non-sway?
- How does the choice ‘1st or 2nd order calculation’ affect the buckling lengths and what is the deal with imperfections?

Global and local imperfections will increase the second order effects.

When you let Diamonds calculate the buckling lengths (regardsless the chosen method), don’t forget to define the groups for buckling.