Pipes

Ah, this is the sequel => from here. :-)

Indeed it is. To me, those look like HVAC ducts, rather than electric wiring. Can't imagine why they'd be needed for a parking garage, though. The white PVC pipe might be for draining water from the open 2nd floor.

I came to the conclusion that they were electric cables, because of
a) the large radius and
b) because they are metallic coated. That's usual for such kind of wires.
The white PVC pipe looks like it's heat-insulated. So it could be a heating pipe.

I will bow to your expertise, Mr. Poly!

Well, to be completely sure, I'd suggest you drill some holes with a pointed screwdriver or something similar ;-)