Why to use a built-up steel cross-section?

IDEA StatiCa Connection can add fixed support only to one member. If you have a connection like the one in the figure, you need to use a composed cross-section (for the column).

You could use several predefined types from the Cross-section navigator

or define your own type in the General cross-section editor.

You can design joints defined by general cross-section with several parts to satisfy your needs.