The Special tab defines special sections (sections with a corrugated web, castellated sections, welded sections: SFB, IFBA, and IFBB). The following images shows the Special tab on the New Section dialog.
You can define the following types of special sections:
Note: Not all members with special sections are designed in the steel or aluminum design modules. Members with a corrugated web and castellated members can be designed only in accordance with the Polish steel code. Welded members SFB, IFBA, and IFBB can not be designed in Robot.