When you run the steel verification on an CHS profile, you get the error
- The relevant CHS-section is of class 4. Cross-sections of class 4 require effective properties. Diamonds cannot calculate these effective properties.
- Keep in mind that thin walled CHS-cross sections can also be seen as a shell structure. EN 1993-1-6 defines the strength and stability rules for shell structures. Diamonds does not support this part of Eurocode.