http://design.transportation.org/Documents/TurnRadii,GreenBook2004.pdf
Turning Radius Guidelines for Trucks
My past (20 years ago) experience says "yes", but the trailers have grown by five feet, and the tractors themselves are now most likely "longnose" units instead of cabovers.
There are plenty of guidelines and diagrams on the 'net.
On a tight, but doable turn, with no obstacles on the right side of the road being departed, the driver would:
Before the turn, slide the trailer tandems to the extreme forward position, making the trailer's wheelbase as short as possible (but increasing the "alligator tail" of the trailer), and get the truck/trailer as far to the outside lane as possible.
When making the turn, the driver would start the turn a bit late, which would place the tractor's nose being centered on the opposite curb. At that point, the driver would reverse the steering wheel, and back up the tractor, increasing the tractor/trailer's angle.
[Or is that "reducing" the tractor/trailer's angle
]
With the increased "jack-knifing" of the tractor/trailer, and the tandems slid forward, if the turn can be made, it will be made, as long as the "alligator tail" doesn't take out a telephone pole, other vehicles, etc.
It seems your question can be re-phrased as "If both roadways are 28 foot wide, and given the use of both lanes of both roadways, can a modern tractor/trailer make a 90 degree turn?" I say yes, but the above technique may be required.
I started my truck-driving career in Seagrove, NC, where the two lane roads were barely 16 foot wide. I recall seeing the outside tires of my 102 inch wide trailer hanging over the pavement, while going down the road. The front (steer) axle was 8 foot wide, so no problem
keeping the front wheels on the pavement.