As you set up your simulation, changes you make to the model can require your attention. When you change components within the assembly, and switch to the Frame Analysis environment, the Update command 
in the Beams panel activates.
Also, there is a browser node decoration, lightning bolt 
, indicating to update the affected beams and nodes.
Click Update to recompute the beam model from the source assembly.
The graphics window and browser update to show the changes. Converted beam model is up-to-date and corresponds to a specified assembly state. Beam model is updated in the active simulation only.