How is a sharp curve defined?

[Adelyn]

Sharp curve refers to a curve with a horizontal curve radius of less than 50 meters. Sharp curve to the left: The sharp curve to the left traffic warning sign is set at an appropriate position in front of the road with a sharp left turn. The sharp curve to the left traffic warning sign is mostly found on mountain roads. Mountain roads are a high-risk area for accidents, extremely dangerous, so it is essential to drive slowly when going up or down the mountain. Driving precautions: Develop the habit of fastening your seat belt when driving, and make sure the car door is closed tightly while driving. When passing through the intersection of the main road and the auxiliary road, pay attention to slowing down. If you are not sure whether there is a car coming out of the intersection, you must slow down and pass slowly. Always use the turn signal when changing lanes.

[IkerLee]

From a highway design perspective: sharp bends are not arbitrarily determined by feeling. I've checked the road design standards, which mainly consider the turning radius and design speed. For example, in urban roads, a turning radius of 250 meters or less is considered a sharp bend, while in mountainous areas, it's relaxed to 125 meters. The most extreme are those sharp bends with angles less than 70 degrees where you can't see oncoming traffic—road authorities install convex mirrors on the roadside. During construction, superelevation is also designed for curves, tilting the outer road surface to facilitate drainage and prevent skidding. Otherwise, driving through such bends in the rain could easily lead to drifting. When navigating sharp bends, you can distinctly feel the steering wheel being pulled, and for bends with smaller radii, you need to turn the steering wheel more than half a turn to get through.

[DiJuliet]

From the driving experience perspective: Only after driving hundreds of kilometers on mountain roads do you truly understand what a real sharp turn is. Those bends where you turn the steering wheel 90 degrees and still can't make it—those are essentially sharp turns. Driving an SUV through sharp turns is most noticeable; if the speed exceeds 40 km/h, items inside the car can be flung out. Experienced drivers know that when they see a sharp turn warning sign with a yellow background and black arrow, they should brake 20 meters in advance and only step on the accelerator after completing the turn. Especially when driving a manual transmission car, downshifting before a sharp turn is a must to use the engine to stabilize the speed. Back when I first got my license, my palms would be drenched in sweat while navigating sharp turns on mountain roads.

[Erica]

From a vehicle engineering perspective: Taking sharp turns puts the most strain on a car's suspension and steering systems. The smaller the turning radius, the greater the pressure on the outer tires. A good car's suspension will keep body roll within 5 degrees. When economy cars take sharp turns at speeds as low as 30 km/h, you can hear the tires squealing, which indicates they're approaching their grip limit. Electric vehicles actually handle sharp turns more steadily because the battery weight in the chassis lowers the center of gravity. I remember last time I took a sharp turn in a certain new model - the steering wheel had only turned one-third when the ESP intervened, automatically applying light brake pulses a few times, and the body didn't even sway.

[BellaDella]

From a traffic regulation and safety perspective: The driving test manual clearly defines a sharp turn as one with a turning angle exceeding 70 degrees. Such bends must have a speed limit of 30 km/h or below. Last year's traffic accident report revealed that 38% of mountain road accidents occurred at sharp turns, particularly at blind curves without guardrails, which are the most hazardous. Experienced drivers will honk and use high beams before entering the curve to alert oncoming traffic. Overtaking on a sharp turn is strictly prohibited, as encountering pedestrians or a broken-down vehicle suddenly around the bend can be disastrous. On highways, curves with a radius less than 650 meters are also considered sharp turns, and speed limit signs will be posted roadside.