Asphalt pavements are asphalt and concrete paving, compaction and formation of various types of pavement. Asphalt concrete is made with a certain viscosity and an appropriate amount of asphalt materials with a certain grade of mineral aggregate, after adequate mixing to form a mixture. Asphalt concrete as asphalt pavement material in use to vehicle load repeatedly, as well as the long-term effects of environmental factors. Asphalt concrete in some capacity at the same time, must also have good durability to resist natural factors. In other words, to be able to show sufficient under the environment of high temperature stability, low temperature crack resistance of situations, good water stability and lasting anti-aging and facilitate safe skid-resistant characteristics, asphalt pavement to ensure good service.
Asphalt concrete for the construction of bituminous materials for road asphalt and coal tar pitch and, in addition, there are natural asphalt. In some countries or regions are also making use of or mixed with natural asphalt mix. According to the variety of different aggregates can be divided into crushed stone, gravel, sand, slag type, gravel is the most common. Nature and marking requirements of asphalt, asphalt pavement type, the climate and traffic situation varies; hot mix or thermal perfuse and in hot areas and heavy traffic on the road should use thicker asphalt; cold or cooling method, perfuse and in cold areas and should use a thin, light traffic road asphalt.    mixture maximum particle size are different, can be divided into coarse grains (35-40 mm), medium (20-25 mm), fine (10-15 mm), sand (5-7 mm) and several classes. According to the mixture of varying degrees of density, can be divided into dense, semi open grade and grading, such as class, open-graded mixtures, also known as bituminous macadam.