Senior Technical Support Engineer, Bridge
MSc., Structural Analysis Specialist, Civil Engineer, RM Bridge Enterprise
Bentley Systems Inc.
I could see that there is this segment in the model, first you need to check if all this superstructure elements are actually there.It seems to me that in the other visualization the isometric view was giving the impression that something else could be missing. I don't think it is the case. In RM Bridge right click at the screen, select View Options and turn on the options Draw elements, Draw elements bodies and Transparency You should see something like the image below after you had added the Linear Spring Elements for connecting the superstructure with the substructure.
I hope this allows you to continue.