Stone mastic asphalt, also simply called as SMA, is a special type of asphalt concrete composed of asphalt, fiber stabilizers, sand powder, and some fine aggregates. These components combine to form a robust road surface structure. It is primarily used for the construction of heavy traffic roads, airport runways, high-grade highways, and steel bridge road surface layers. Additionally, it is employed in moisture prevention for building construction. Let’s check its characteristics first.
Characteristics of SMA
1. It possesses high resistance to rutting and temperature stability.
2. The SMA exhibits excellent crack resistance.
3. It demonstrates outstanding durability, with approximately a 40% increase in service life compared to traditional asphalt concrete. The use of modified asphalt can further enhance its performance.
4. The stone mstic asphalt offers good skid resistance.
5. While the initial investment is higher, the average annual cost is lower when considering its extended service life.
In Which Areas of the world is SMA Used?
SMA has certain advantages over traditional asphalt concrete in certain performance aspects, so it is widely used in many countries and regions. Here are some of the main regions where SMA is used:
- Europe: SMA was first developed and widely used in Europe. Many European countries, such as Germany, France, Netherlands, Switzerland, Spain, etc., use SMA in their road construction projects. The European standard EN 13108-5 details the performance and specifications of SMA.
- North America: In the United States and Canada, SMA is also widely used. Some states in the United States, such as California, Texas, Illinois, etc., have adopted SMA as a road surface choice to improve the performance and life of the pavement.
- Asia: Some Asian countries have also begun to adopt SMA technology, especially in the construction of highways and important traffic arteries, like Russia, Kyrgyzstan, Tajikistan, Malaysia, etc.
It should be emphasized that the use of SMA is not universal worldwide and depends more on local engineering needs and available resources. Therefore, whether SMA is used when producing asphalt at an asphalt mixing plant will vary from region to region. In any case, the asphalt production process needs to follow relevant engineering standards and regulations to ensure road quality and safety.