Asphalt is used today as one of the most commonly used road-building materials, GOST of which implies the need to maintain density and composition. To date, several brands, varieties and types of this material are known. The classification is based not only on the initial components, but also on the ratio in the composition of their mass fractions. Asphalt is also subdivided into categories for the reason that the components can have a different fraction, as for crushed stone and sand, as well as the degree of purification of the mineral powder.
Composition
The composition of asphalt suggests the presence of:
- gravel
- crushed stone;
- sand;
- bitumen;
- mineral powder.
As for crushed stone, some varieties of this coating do not provide for its use. However, crushed stone or gravel is necessary if the territory is paved, taking into account strong short-term loads and high traffic to the coating. Mentioned materials in this case act as a frame-forming protective element.
Mineral powder is used as a mandatory feedstock ; it is contained in any varieties and grades of asphalt. The mass fraction of this powder is determined taking into account the requirements and tasks for viscosity. If you use mineral powder in a large volume, the material will receive the ability to damp vibrations of bridge structures without being covered by cracks.
As mentioned above, sand is used in most grades and types of asphalt. Its quality is determined by the degree of purification and the method of preparation. The material can be mined in an open way, in which case it requires careful cleaning. The cornerstone of the industry is bitumen. This is an oil refining product.
The mass fraction of bitumen in most varieties of asphalt does not exceed 5%. However, if necessary, asphalting of territories that have a difficult terrain, bitumen can be used in a volume of up to 10% or more. This raw material gives the density and elasticity of the mixture after hardening. The finished composition is easily distributed on the site, because it has a fluidity.
Density and basic characteristics of natural asphalt
Asphalt density is one of the first characteristics that interests professionals and private developers. Its natural variety is a fusible solid mass of black. At a break, the material may have a dull or shiny color.
The density of asphalt is 1.1 g / cm³. The melting temperature may vary from 20 to 100 ° C. The composition contains oil in an amount of 25 to 40%, as well as a tarry asphaltene substance, which can be contained in an amount of 60 to 75%. As for the elemental composition in percent, it looks as follows:
- C - 80-85.
- H - 10-12.
- S is 0.1-10.
- About 2-3.
The density of asphalt is already known to you, however, this characteristic is not the only one that interests consumers. Among other features, it is worth highlighting the method of formation from residues or fractions of oil as a result of evaporation of light components and oxidation under the influence of hypergenesis.
Characteristics of artificial asphalt
Artificial asphalt is also called asphalt mix. It is a compacted composition of mineral powder, crushed stone, bitumen and sand. There is hot asphalt, which is laid by compaction when exposed to a temperature of 180 ° C or more. If low-viscosity bitumen is used in the manufacturing process, then laying is carried out at a temperature in the range from 40 to 80 ° C. If liquid bitumen is used, the asphalt is cold and compacts at temperatures up to -30 ° C.
The main brands of asphalt and GOST
The density of coarse-grained asphalt was mentioned above, however, you should also be aware that the percentage of ingredients in the composition affects the grades and types of asphalt. Today, three varieties are generally accepted, which are made according to GOST 9128-2009. In these standards, you can learn about the possibility of adding additives that increase hydrophobicity, frost resistance, wear resistance and coating flexibility.
Asphalt grade 1 contains:
- screening out;
- sand;
- crushed stone;
- concrete;
- mineral powder.
This coating includes dense materials in which the gravel content can vary from 30 to 60%. This should include high-density, gravelly porous and porous asphalts. Asphalt, the GOST of which must be taken into account during production, can be manufactured under the brand 2. The composition of this material contains:
- crushed stone;
- concrete;
- screening crushing;
- sand;
- mineral powder.
This category includes highly porous sandy, porous, as well as dense asphalts, in which the gravel content can vary from 30 to 50%, while the mixture from crushing screenings and sand can comprise up to 70%.
The density of asphalt is already known to you, but you also need to know that there is an asphalt grade 3, it contains:
- screening crushing;
- mineral sand;
- bitumen powder.
In this case, we are talking about mixtures, gravel and gravel in which can be contained in the range from 30 to 50%. Screening crushing and sand are contained in a volume of from 30 to 70%.
Brand Description
The density of asphalt (t / m3) is 1.1. However, this is not all there is to know about properties. For example, grade 1 asphalt can be highly porous or dense with a high gravel content. The area of use of this coating is road improvement and construction. As for grade 2 asphalt, its density range remains approximately the same, but the percentage of gravel and sand varies widely. This asphalt is considered the most average. The mixture is used for the construction of roads, arrangement of territories, repair of coatings, as well as the formation of sites and parking lots.
Conclusion
The density of asphalt (t / m3) is 1.1. But this parameter is not the only one you should know. For example, it is also worth mentioning the asphalt deposit, which extends to the territory of the former USSR, the island of Trinidad, Venezuela, France and Canada. Mixing with mineral components, including gravel and sand, the material turns into a powerful crust on the surface of oil lakes. Such a coating is common in areas of emergence and shallow occurrence of oil-bearing rocks to the surface of the earth.