Built-up steel columns of thin-walled elements

[engineer69]

Hi guys, does anybody have some information about thin-walled cold-formed sections for built-up steel columns? The use of thin-walled cold-formed sections for built-up steel columns, calculation features?

normal cross-sections.png

built-up cross-sections.png

[Таран Д. А.]

Such profiles are used in Russia.
For calculation in Russia are no rules. You can calculate on the Eurocode.