Why Should Vehicles on the Auxiliary Road Yield to Those on the Main Road?

[Elizabeth]

Main roads typically have higher traffic volume and faster-moving vehicles. The specific reasons are as follows: 1. Mainline: The main road serves as the primary route, while the auxiliary road functions as a secondary route, requiring vehicles on the auxiliary road to yield to those on the main road. 2. Road Surface: Main roads are wider and accommodate more traffic, whereas auxiliary roads are narrower and generally have slower speeds, necessitating yielding. Additional Information: Auxiliary roads in ground-level expressways should be located on one or both sides of the main road. For elevated roads, auxiliary roads should be situated at ground level beneath the elevated structure. In urban areas, auxiliary roads should preferably be continuous. In suburban expressways, auxiliary roads may be continuous or intermittent. Auxiliary roads on both sides of the main road should adopt one-way traffic, while those on a single side may allow two-way traffic.

[LeKate]

When I first started driving, I didn’t understand this either, but after driving more long-distance trips, I got it. The traffic on the main road is like a high-speed conveyor belt, and cars merging from the auxiliary road are like throwing things onto the belt. If every auxiliary road car forces its way in, main road cars have to constantly hit the brakes, and the entire traffic flow gets completely disrupted. The traffic police here often say that when the average speed on the main road is over 50 km/h, if you cut in from the auxiliary road and force main road cars to brake suddenly, the probability of a rear-end collision doubles. Once, I saw an auxiliary road car rushing in at a suburban roundabout, causing three cars to crash into each other like a string of candied haws. Now, when merging onto the main road, I always keep my foot on the brake and wait for a gap—safety is far more important than rushing those few seconds.

[MadisonAnn]

A friend who drove a taxi for ten years taught me a trick: imagine the main road as a river's main channel, and the auxiliary road as a tributary. The main channel has a fast flow, and if a tributary suddenly pours water into it, it will surely flood. The main road has fast-moving and dense traffic. Last time, I was on the auxiliary road under the southern overpass and didn't yield to a bus on the main road, causing nearly everyone on the bus to stumble. The traffic police explained that the law stipulates this because the main road has priority right-of-way, similar to how emergency vehicles have priority. Especially on rainy days when the road is slippery, heavy trucks on the main road can't stop in time, making it even more dangerous. Now, when teaching my daughter to drive, I also emphasize: when you see a diamond-shaped yield sign, step on the brake, and only merge onto the main road when you can see enough distance between vehicles—about the space of two utility poles.

[MadisonRose]

Simply put, it's a life-saving rule. The speed on the main road is generally over 60 km/h, while your speed from the auxiliary road is only around 20 km/h. This speed difference is like jumping onto a moving treadmill—it's almost certain to cause a crash. Traffic management data shows that 70% of accidents caused by auxiliary road vehicles failing to yield are side collisions, with particularly high injury rates for passengers. Just last week, near our neighborhood entrance, a ride-hailing car didn't yield to a dump truck on the main road, resulting in the car door being completely dented. During road design, main roads are made wide and straight with good visibility, which can make drivers less vigilant. A sudden merge from another vehicle leaves them with little time to react. That's why you must stop and observe at the yellow dashed line, waiting for the main road traffic to pass before proceeding.