here in West Oz they truck them around 8 per trailer, mounted vertically in frames, 4 up one side of the trailer, 4 up the other side. They have special tyre handler forklifts which they use to unload them at the minesite. The tyre handler machines look like large forklifts with grippers rather than tines, and the grippes allow the machine to rotate the tyre, tilt the tyre, and the mast allows for lift as well. - I will try and get photos the next time I see a load on the road.