You’ll have to create planes which are perpendicular to the arc.
If you can’t figure out how to do this, go through the Modelab Primer
Then look at this example: Sweep many rails with profiles - #2 by HS_Kim
I found it with this search: Search results for ‘beams oriented’ - McNeel Forum
In case you are still stuck, please post your Rhino and Grasshopper files.