Highway regulations:
According to the Technical Standard for Highway Engineering of China's Ministry of Communications, expressway refers to a highway that can adapt to the annual average day and night passenger car traffic of more than 25,000 vehicles and is designed for cars to drive at high speed in a single lane, and all access is controlled. Although different countries have different names for expressway, they all refer to expressway with more than four lanes, two-way separation, complete control of entrances and exits, and all three-way intersections.
In addition, in many countries, the direct trunk lines that partially control the entrances and exits, but not all adopt interchanges, are also called expressway. For many years, the International Road Federation has listed direct trunk lines in the category of expressway in its annual statistical report.
The construction of expressway can reflect the traffic development level and even the overall economic development level of a country or region. Expressway belongs to high-grade highway. Generally, it can adapt to the speed above 120 km/h, and the pavement has a width of more than 4 lanes.