I actually have no idea what they are constructing, bonus points on offer for knowing that… 
That looks like the airport at Stuttgart, heading East on the A8.
No idea what they are building, it might be a new road bridge.
Spot on…
There appears to be about 3 of those things going across the carriageway, from a distance I thought it may have been a posh new stadium for the world cup…
I came through there this week and had as good a look as I could.
Just off to the left of this pic, they have just completed what looks like two spiral driveways, which seem to line up with the two bridge like constructions over the Autobahn.
I now think those constructions are two large multi storey car parks.
thats the new “messe zentrum”(exebition center) at Stuttgart airport. The 3 bridges are the Parking decks, they pushed them things over the Motorway on tracks, took about 10 hours for each one
Ive often gone past this site and wondered what they were for 