Why is the speed limit on the He-Da Expressway set at 80 km/h?

[FernandoAnn]

The He-Da Expressway has a speed limit of 80 km/h only on certain sections, primarily due to technical conditions affecting interchange areas and tunnel sections. The design speed of the He-Da Expressway is 100 km/h, but it is limited to 80 km/h in areas such as the Dongjiagou Interchange curve and the Jinshan Tunnel. The specific reasons are as follows: 1. Dongjiagou Interchange Curve: Interchanges are critical nodes on expressways and frequent sites of safety incidents, hence the design speed is set at 80 km/h. If the design speed were too high, it would result in insufficient length for deceleration lanes, causing vehicles to enter the ramp at speeds exceeding the required limit. Similarly, acceleration lanes would also be inadequate, leading to lower speeds when merging into the main lane. Both scenarios pose significant safety risks. 2. Jinshan Tunnel: Poor lighting inside the tunnel affects driving visibility. If the design speed were too high, it would be difficult to react promptly in case of sudden emergencies.

[LeRicardo]

Last time I drove on the He-Da Expressway, I noticed the strict speed limits. After asking a friend from the local road administration, I learned that this highway has many sections winding through mountains and hills, like the Changbai Mountain area in Jilin, where there are often continuous stretches of steep downhill curves for over ten kilometers. Driving at night, I once encountered thick fog with visibility less than 50 meters; if I hadn't slowed down in advance, it could have been dangerous. The tunnel clusters are also critical, especially the section from Jingyu to Fusong where tunnels follow one after another, and the sudden changes in lighting can be disorienting. I heard that the accident rate was high in the early years, with trucks overheating their brakes on long downhill stretches and crashing through guardrails. Now, the 80 km/h speed limit throughout is meant to force everyone to drive slower. Actually, driving slower saves fuel—I calculated that the same trip only takes 20 minutes longer, but the safety factor doubles.

[Kingston]

As someone who frequently drives long distances, I find the 80 km/h speed limit on the Hegang-Dalian Expressway quite reasonable. Last year, I drove through the Liaoning section, where the road surface was so uneven it felt like riding a roller coaster, and some sharp curves were designed in a way that even 70 km/h felt too fast. The permafrost issue is particularly noticeable in the Heilongjiang section, with hidden ice patches appearing unpredictably in winter. Once, my car skidded when crossing a bridge at just 60 km/h. The most frustrating part is the frequent maintenance on some older sections, like the Tonghua stretch, where lane closures are common year-round. Suddenly dropping from 120 km/h to 80 km/h makes it nearly impossible to brake in time. I remember driving at 100 km/h through a construction zone once, and the bumpiness sent all the luggage in the trunk flying. Looking back, this expressway wasn't designed for speeding—80 km/h is just the right speed to spot wild deer by the roadside.

[WilliamDella]

Driving a new energy vehicle on the He-Da Expressway gave me a profound realization—the 80 km/h speed limit is scientifically sound. The entire highway traverses three ecological reserves, and sections like Laotudingzi often have wild animals crossing. Last autumn, I personally witnessed forest rangers holding signs by the roadside warning about deer herds—driving at 100 km/h would definitely make it impossible to stop in time. Tunnel lighting is also an issue. I calculated that if you don’t slow down before entering a tunnel, it takes about 3 seconds for your pupils to adjust—enough time to rear-end the car ahead. The most critical issue is freeze-thaw cycles—some sections in spring thaw look like they’ve been bombed, and 80 km/h allows you to dodge potholes in time. Don’t complain about the slow speed—last year during Qingming Festival, accidents on this stretch dropped by 40%.

[TeaganAnn]

Old Wang from the maintenance team told me that many bridge piers on the Heida Expressway have sunk. The repeated freeze-thaw cycles of the permafrost have deformed the roadbed, and one section has been patched five times in three years but still has bulges. The most troublesome issue is tunnel water seepage—the tunnel walls along the river section drip year-round, turning into ice pillars in winter. I remember in 2018, a sports car speeding at 110 km/h in the Huanren Tunnel hit an icy patch, lost control, and crashed into the wall. Now, during maintenance, they use ground-penetrating radar vehicles, which have scanned over twenty loose rock layers. So don’t complain when you see the 80 km/h speed limit—it’s hard-earned experience from past accidents. By the way, 37% of the Heida Expressway sections have exceeded their designed lifespan, so driving slower is better for your car too.

[SanMorgan]

Driving back to my hometown with my child via the Heida Expressway, the 80 km/h speed limit actually made me feel more relaxed. When passing the Changbai Mountain service area, traffic police displayed wreckage from accidents: an SUV that crashed through the guardrail and fell into an 80-meter-deep valley, and a container truck that was compressed into a metal pancake in a tunnel rear-end collision. The most heartbreaking was the 34-car pileup in 2019 due to fog—drivers couldn't brake in time because of high speeds. Now, maintaining 80 km/h the whole way, I don't have to death-grip the wheel around curves, and my child doesn't get carsick in the back seat. I've observed several accident-prone spots, like the sharp left turn at the Jingyu Interchange, which has seen zero fatalities in three years since the 80 km/h limit was imposed. My fuel consumption dropped from 9L to 7.2L, and even tire wear has decreased.