A woman remains critical after the collision near Cheriton Bishop on Wednesday.
Police believe a four-vehicle combination of a lorry towing a small and large trailer plus a caravan collided with the central barrier of the dual carriageway and collided with three cars and a van.
A woman in her 30s was airlifted to Derriford Hospital in Plymouth, where she remains in a critical, but stable condition.
A man from Wiltshire, who's still in hospital, is helping police with their enquiries.
Highways England have tweeted to say repairs to the barrier are complete and they'll shortly start to remove the lane closures.
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