Line Constraint

Regarding this attached project with this mail, I like to ask about linking two different cross-sections with a line constraint in SOFiSTiK: When the manual mentions “infinite stiffness,” it means that the connection between the elements is assumed to be perfectly rigid. This implies that there is no relative movement between the connected sections, making them behave as a single crossection or not? I tried to get the combined moment of inertia (Iy, Iz) in sofistik but it wasn’t possible to get. is it possible to get combined moment of inertia after using line constraint. for example I have used it in my project to combined structural line 78 with 79 and also between other structural line, so that it could function as single I section. Dose this concept hold true or False ?

2859-37-2024-Krbw Stabbogenbrücke Kiel.dwg (535.4 KB)
2859-37-2024-Krbw Stabbogenbrücke Kiel.sofistik (141.7 KB)