As a rapidly developing economic power, China has maintained a high-speed development in infrastructure construction. As one of the main ways to connect urban and rural areas and connect internal and external regions, road transportation has also made great progress in recent decades.
As of September 2022, China's total road mileage has reached about 5.28 million kilometers, of which the mileage of expressways exceeds 170,000 kilometers, making it one of the countries with the longest total mileage of expressways in the world.
In addition, China's road development also has many highlights, such as the world's highest highway altitude and the world's largest cross-sea bridge. It can be said that China's road transportation has developed into an extremely important part of national infrastructure construction, playing an important role in promoting economic development and facilitating people's travel.
But have you found a problem? There are two materials for road construction, so it is cement or asphalt. Why can't all asphalt roads be used?
Today we will discuss whether it is better to use cement or asphalt for road construction.

Cement VS Asphalt
Cement road and asphalt road are two different road construction materials. Cement road is mainly composed of cement, sand, gravel and other materials, while asphalt road is mainly composed of asphalt, mineral powder, gravel and other materials. Let's talk about the advantages of cement road and asphalt road respectively.

Lifespan
Cement roads are harder than asphalt roads. The thickness of cement roads is generally more than 20 cm. Because of its good structural stability and ability to withstand the pressure of heavy vehicles, it is usually used in places such as highways and airport runways that require durability and stability.
Relatively speaking, the thickness of asphalt pavement is only about 5 cm, so it is usually only suitable for light traffic occasions such as urban roads.
In terms of lifespan, cement roads are also slightly better. Generally speaking, the service life of cement pavement can reach more than 30 years, while the service life of asphalt pavement is only about 10-15 years.
This is because the chemical properties of cement are more stable than asphalt, and its antioxidant properties are stronger. It can maintain its hardness and stability for a longer time and is not easily affected by environmental factors such as sun and rain.

Environmental damage
From the production process point of view, the production process of cement roads requires a lot of energy consumption and also produces certain carbon dioxide emissions. The production of asphalt pavement can relatively save some energy and emit relatively less carbon dioxide. Therefore, in terms of the production process, cement roads may be slightly more destructive to the environment.
But from the use stage, both cement roads and asphalt roads will cause certain damage to the environment. Asphalt pavement tends to soften in hot weather and releases volatile organic substances, which have a certain negative impact on air quality. Concrete pavement is relatively stable and does not produce similar volatile substances. However, the surface of cement pavement is relatively hard, and when vehicles drive on it, it will produce certain noise pollution. At the same time, cement pavement will also increase the risk of traffic accidents.

Cost
In terms of construction cost, cement roads are generally more expensive than asphalt roads. Cement roads require more materials and a more complicated construction process, so their construction cost is relatively higher than asphalt roads. At the same time, cement roads take longer to build, which will also increase their construction costs.
In terms of post-maintenance, cement roads require relatively higher maintenance costs due to their better hardness and stability. For example, if there are cracks or potholes on the cement road, the cost of repair will be relatively high. Asphalt roads are relatively low in maintenance costs because they can be remedied by laying a new layer of asphalt.
However, it should be noted that although asphalt roads are relatively more economical in terms of construction costs and post-maintenance costs, their service life is relatively short and they require more frequent maintenance and replacement, and these costs also need to be taken into consideration.

Safety
Let's start with the friction coefficient of the road surface. Both cement roads and asphalt roads have good friction and can effectively provide traction and braking force when vehicles are driving.
However, asphalt pavement has good elasticity and viscosity, so when driving on rainy or slippery roads, the friction coefficient of asphalt pavement is relatively higher, and it is easier to provide stable road friction, thereby reducing the risk of vehicle skidding or loss of control.
Secondly, from the perspective of road surface flatness, cement pavement is relatively harder and smoother, which can better withstand the impact and vibration generated by vehicle driving and provide a more stable driving environment.
Asphalt pavement is relatively softer, with a certain degree of deformation and ups and downs, which may cause bumps when the vehicle is driving, increase the difficulty and fatigue of the driver, and reduce driving safety.
Third, in terms of pavement durability, cement pavement is relatively stronger, more stable, has a long service life, and is not easily affected by external factors such as climate and temperature.
Fourth, asphalt pavement is relatively fragile and easily affected by environmental factors such as sun exposure and rain, resulting in problems such as pavement aging, cracking, and deformation, which in turn affects driving safety.
By comparison, it is not difficult to find that cement roads have their advantages and asphalt roads have their advantages. Why are highways basically asphalt roads, but the toll station is cement road?

Highway paving
What advantages are needed to pave roads on highways?
Safety, safety, and safety.
As we just said, asphalt has good adhesion and elasticity, and can adhere well to the base road surface to form a tight connection structure, thereby improving the durability and bearing capacity of the road.
In addition, asphalt also has good waterproof performance, which can effectively prevent rainwater from penetrating into the lower part of the road surface, avoiding problems such as foundation softening and settlement.
In addition, the surface flatness and friction coefficient of asphalt-paved roads are high, which can provide better driving stability and comfort, and improve driving safety.
When driving on highways, the most important thing is to be able to brake. How many traffic cases have accidents because of the inability to brake. Of course, in addition to safety, there is another advantage that is very important, that is, cheapness.
Road construction costs money, and long roads cost more money. For a country like my country with a huge land area, road construction costs even more money. So when we choose road materials, we should not only choose cheap materials for repair, but also cheap materials for maintenance. Compared with other paving materials, asphalt has lower construction and maintenance costs, which can bring economic benefits to highway construction and operation. Therefore, asphalt is also the best choice for highways. Why toll stations use cement? Highway toll stations are one of the important facilities on highways. They play a role in managing traffic flow and collecting tolls. However, you may be curious why the roads at these toll stations are paved with cement instead of asphalt like highways. In contrast, cement is more suitable for paving roads at toll stations. The first reason is that compared with asphalt, cement is stronger and can withstand the pressure of a large number of vehicles passing by. This is especially important in the areas around toll stations, because these areas often need to bear heavy loads from trucks and other heavy vehicles. Secondly, due to the greater durability of cement, the roads at toll stations do not need to be repaired and repaved as frequently as asphalt roads. This means that the life of the road is longer and a lot of maintenance and repair costs can be saved. Finally, cement roads are more environmentally friendly than asphalt roads. During the asphalt production process, a large amount of harmful gases and waste are generated. Making cement releases less carbon dioxide, and when cement roads are demolished, cement materials can be recycled and reused, reducing waste and environmental impact.
Now you know the advantages of cement roads over asphalt roads.

Conclusion
In summary, China's highway construction uses a variety of materials, each of which has its own unique advantages and scope of application. Whether it is asphalt, cement or other materials, the best construction plan can be selected according to different road sections and traffic conditions to ensure the safety and reliability of the highway system.
With the development of China's economy and social progress, highway construction will face more challenges and opportunities. We must continue to innovate, improve highway quality, and promote the rapid development of transportation. We believe that with the joint efforts of all parties, my country's highway industry will surely usher in a better tomorrow.