An accident in Roane County Tuesday morning caused some traffic problems for several hours. A tractor-trailer rig overturned on I-40 eastbound in the area of mile marker 343 partially blocking the right-hand lane. Traffic was bottle-necked from around 8:30 AM until well into the afternoon. The rig had to be off-loaded onto another truck before it could be straightened and hauled down the mountain. The driver was not seriously injured and an investigation into the wreck is underway.