Why Should the Main Road Vehicles Go First Compared to the Service Road Vehicles?

[McBella]

Generally, the main road has more lanes and faster speed, so vehicles on the service road should yield to those on the main road. Roads with high traffic volume are designated as main roads, which serve as the trunk lines, while service roads are the branch lines. Branch line vehicles should yield to trunk line vehicles. The specifications for service roads are as follows: 1. In ground-level expressways, service roads should be set on one or both sides of the main road. For elevated roads, service roads should be set on the ground level beneath the elevated road. In urban areas, service roads should be continuously set. For expressway service roads located in suburban areas, they can be set continuously or intermittently. 2. For the cross-section layout of ground-level expressway service roads, physical barriers or marked lines should be used to separate motor vehicle lanes from non-motor vehicle lanes. When motor vehicle lanes and non-motor vehicle lanes are physically separated, the width of the motor vehicle lane should not be less than 7.5m. When motor vehicle lanes and non-motor vehicle lanes are separated by marked lines, the width of the service road should not be less than 8.5m.