It happened around 5:30 a.m. near Exit-170 / US-70.
Troopers said the large truck went over the metal guardrail for I-85 south before it ended up straddling the metal guardrail for I-85 north.
"It was very fortunate the truck did not end up in the northbound lanes," Trooper D. Dugan said.
The truck was empty. The driver was taken to the hospital with minor injuries.
Troopers were working to learn what caused the driver to lose control.