What is the Concept of a Two-Way Four-Lane Road?
2 Answers
Two-way four-lane road: There are a total of four lanes in both directions. For example, there are two lanes heading east and two lanes heading west, making it a two-way four-lane road. According to the relevant national standards, the width of each lane on urban roads is 3.75 meters, diversion lanes at intersections are 2.3-2.5 meters per lane, trunk roads (including highways) have a lane width of 3.75 meters, and shoulders (emergency stopping lanes on highways) are 1.5-3.5 meters wide. Different types of two-way four-lane roads: 1. Two-way four-lane highway: Designed for speeds of 60-80 km/h, with a road width of four lanes. A median strip and green belt can be set up in the middle, with each lane being 3.75 meters wide. When necessary, a non-motorized vehicle lane of over 3.5 meters and a sidewalk of over 4 meters must be established. 2. Two-way four-lane expressway: Designed for speeds of 80-120 km/h, with a road width of four lanes and two emergency lanes. A median strip is set up in the middle, using high-grade pavement such as asphalt concrete or cement concrete, equipped with complete signs, markings, signals, and lighting devices; pedestrians and non-motorized vehicles are prohibited from walking on the road, and intersections with other routes are designed as overpasses, pedestrian bridges, or underpasses.
As an ordinary driver, I'm quite familiar with the concept of a dual four-lane road. Simply put, it's a road divided into two directions—one for outgoing traffic and the other for incoming—with two lanes in each direction, making a total of four lanes. This design is commonly seen on daily urban roads, such as main thoroughfares or highway entrance sections. For me, it makes driving smoother because I can overtake slower vehicles in the same direction, avoiding traffic jams. There are many benefits: higher traffic flow, fewer accidents (since there's usually a median barrier or markings to prevent head-on collisions), and in rainy or snowy conditions, multiple lanes provide extra buffer space for safety. The downside? Some rural areas lack this design, making roads feel more congested. Overall, it's an efficient layout that saves space and boosts efficiency, serving as one of the pillars of modern urban transportation.
