First thing I think is: what's the posted speed limit, and how fast are they actually going?

This is a construction zone we're talking about. Limit should be dropped, maybe doubly so for trucks. On 79SB just past the Coraopolis exit, there's an S-curve with very obvious signage for trucks to limit to 45mph. If I saw a truck flipped in that stretch, my first thought would be they took a turn too fast.

If the problem is the lane and not the speed, put up one of those "no trucks X lane" signs. This shouldn't be a hard fix.