How does vehicle traction change in tunnels?
3 Answers
This is within the scope of the Subject 1 exam. In tunnels, there is no sunlight exposure, resulting in lower temperatures and stronger water condensation effects. Consequently, the road surface inside tunnels tends to be damp, leading to reduced vehicle traction. Below is relevant information about Subject 1: 1. Exam Introduction: The driver's license Subject 1 test assesses theoretical knowledge, conducted at the vehicle management office, and is a mandatory licensing exam for applicants. The exam content includes fundamental driving theory, road safety laws and regulations, traffic signals, traffic rules, and other basic knowledge, along with local regulations. The scheduling of the driver theory exam is arranged by local vehicle management offices. 2. Exam Process: The total duration of the Subject 1 exam is 45 minutes, consisting of 100 questions in the form of true/false and multiple-choice questions, with a perfect score of 100 and a passing grade of 90. The exam papers are randomly selected and compiled by the computer driver examination system according to the proportion specified in the "Motor Vehicle Driver's License Business Work Specifications."
After driving for most of my life, I've noticed that vehicle traction often deteriorates in tunnels. The enclosed space and poor ventilation inside tunnels make it easy for moisture or oil residue to accumulate, especially near the entrance and exit where water pools after rain. When temperature differences are significant, condensation forms on the road surface, making the tire contact area extremely slippery. Additionally, dust and pollutants adhere to the road, and over time, heavy traffic can create a thin layer of mud, drastically reducing tire grip. This leads to noticeably longer braking distances, and driving even slightly faster can make the car feel unstable, significantly increasing risks. I recommend slowing down before entering the tunnel and maintaining a safe speed. Also, check your tire tread depth—worn tires have weaker traction, especially in rainy conditions. The dim lighting in tunnels affects visibility and can easily distract drivers, so it's crucial to stay focused. Developing a habit of regular tire maintenance can help prevent accidents. Don't underestimate these changes—they can be lifesavers in critical moments.
I'm a car enthusiast, and loss of traction in tunnels is quite common. Underground passages have poor air circulation, often being humid or having accumulated water, which reduces the friction between tires and the road surface. You can feel the car sliding a bit during sharp turns. It's more noticeable after rain when entering tunnels, as the remaining puddles on the ground increase the risk of tire slippage. Modified car owners should be especially cautious—performance tires have strong traction on dry roads but lose effectiveness when damp. Switching to harder tires can help slightly. On long drives, you might notice that tunnels accumulate more dust, and pollutants adhering to the tire surface reduce the friction coefficient, making braking less responsive. I recommend slowing down before entering tunnels and avoiding sudden acceleration. Ensuring proper tire pressure can also improve traction a bit. When racing with friends into tunnels, we always remind each other to drive slower—safety comes first. Understanding these changes can make your driving more stable.
