I assume this is related to your other topic: Covering structure with fabric - Rhino - McNeel Forum
Below is a simple solution, not yet taking into account that you might want to have different inner sections for the ‘arches’. The loft component is set to rebuild the offset curves which results in a nice polysurface.
The two input curves are internalised in this file:
section_scale_loft_sweep.gh (21.6 KB)
PS: please not that in your unnamed Grasshopper definition above, you are attempting to orient the closed polysurface from Rhino more than 20000 times on your curve. That is a bad idea 