All lanes were reopened just after 11 a.m.
Several cars were smashed under the rig and the CHP said one person was briefly trapped in the wreck.
Only minor injuries have been reported.
- Photos: Semi jackknifes, catches fire
Fiery big-rig crash jammed 5 Freeway
BURBANK, Calif. The accident, reported shortly before 6 a.m., affected northbound and southbound traffic at Alameda.
