I think we need bridges that go to the fuel station complex, because most of the fuel station traffic is caused by trucks crossing the oncoming lane to go into the fuel station.
Something like the image below, which is very similar to the Calais-Duisburg intersection just after Calais intersection, but completed with traffic lights to control traffic, the lanes coming off the C-D
road will have longer green signals to prevent backups, or the merge lanes coming off the C-D road can be very long or be a dedicated lane with a fence.
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Below: Fuel station access paths that trucks follow to enter and exit fuel station.
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Another way to fix traffic is to separate the lanes passing the fuel station, with road barriers on the outside of both lanes, so the lane next to the fuel station can access the fuel station, but the lane across cannot, these fences should extend quite far to prevent turning around, the next fuel station should be accessible from the other side, so truck that are traveling from Calais, will have to go the the fuel station near Duisburg, and vice versa, I must mention that the lanes should be doubled on the fuel station side, to trucks going to the fuel station can go in their dedicated lane, and truck not going to the fuel station can skip the queues.