The first-class highway is a highway for cars to travel in different directions and lanes, some of which control access and some of which communicate. It mainly connects important political and economic centers and leads to key industrial and mining areas. It is a national trunk highway. The first-class highway can use four or six lanes.
1, four-lane first-class highway:
It can adapt to the design of converting various vehicles into passenger cars in the long term, and the annual average day and night traffic volume 15000 ~ 30000.
2. Six-lane first-class highway:
It can adapt to the long-term design of converting various vehicles into passenger cars, with an average annual day and night traffic volume of 25,000 ~ 55,000 vehicles.
Extended data
Basic features:
(1), with long-distance central isolation belt.
(2) According to the service functions of different roads, choose to keep intersections or adopt full interchanges, and the number of intersections depends on the actual situation.
(3) In principle, motor vehicles are not allowed to mix with non-motor vehicles and pedestrians, and auxiliary roads, non-motor vehicle lanes and sidewalks can be added.
(4) The minimum number of lanes is four lanes, mostly six or eight lanes.
(5) The speed limit is 60km/h-100km/h. ..
Baidu Encyclopedia-Highway Grade
Baidu encyclopedia-first class highway