Density of asph alt concrete: material consumption and composition

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Asph alt concrete is widely used today for landscaping and road construction, which makes it possible to obtain a durable and high-quality coating. This material is a mixture of bitumen and natural materials.

Natural ingredients provide strength, while bitumen is needed to bind them into a single structure. Asph alt concrete is laid using the same technology in different countries, but the quality of the pavement depends on the components that are added or not added to the mixture, this sometimes determines the laying method.

Material density

The density of asph alt concrete is one of the main characteristics of this material. Asph alt concrete, as it is also called, has the form of a building artificial conglomerate, which is formed as a result of achieving the required density of the mixture laid in the structure. The composition is prepared by mixing in special installations under the influence of temperature. In this case, oil road bitumen is used, as well as mineralmaterials of different fractions, they are selected in certain ratios. Polymers, rubber, surfactants, sulfur, etc. are sometimes added.

The density of asph alt concrete depends on the variety. For example, a dense mixture has a density in the range of 2340 kg/m³, as for a porous mixture, its density is slightly lower - 2300 kg/m³. Fine-grained asph alt mix type A, B and C has the following density values: 2385, 2370 and 2343 kg/m³ respectively. There is also sandy asph alt concrete in the “mixture type D” variety, in this case the parameter of interest is 2280 kg / m ^3.

Determination of density

Determination of the density of asph alt concrete is carried out according to laboratory tests of those samples that were removed from the coatings. This parameter is calculated by the ratio of the average density of the material that was taken from the coating to the average density of the overmolded sample.

For each type of mixture, a different compaction factor is applied. For example, for mixtures A and B, the coefficient is 0.99, for a mixture of C, D and D, the main and lower layers, the coefficient is 0.98. If the ingredients contain crushed stone from artificial stones, then the coefficient should be equal to 0.97.

Consumption of asph alt concrete

Not only the density of fine-grained asph alt concrete and its other varieties is important, but also the consumption. Usually this parameter is set at 100 m², but the layer thickness may vary. For a dense and porous mixture with a layer thickness55 mm consumption per 100 m^{2 will be 12.87 and 12.65 tons, respectively. With an increase in the layer to 80 mm, the consumption of a dense and porous mixture will be 18.7 and 18.4 tons, respectively.}

Fine-grained asph alt mix type A has a lower consumption if the layer is reduced to 35 mm. At the same time, it will take 8.35 tons per 100 m². And if we are talking about a sandy asph alt concrete mix of type D, then with a layer thickness of 45 mm, the consumption will be 10.26 tons for every 100 m ^2.

Density meter

Asph alt density meter can be purchased from specialized stores. It determines the density of pavements and bases of the roadway. The purpose of the device is the operational control of density, during which you can find out the degree of heterogeneity and compaction of the bases and road surfaces.

The device can detect non-compacted areas, as well as control critical areas, this should include edges and joints. It can be used to determine the average density of asph alt concrete, which is 2.35 g/cm3. The equipment evaluates the quality of the coating, even before applying the top layer. The device can measure the temperature of the asph alt, determine the compaction coefficient, carry out temperature compensation of the density reading.

Asph alt concrete composition and state standards

The density of asph alt concrete, the GOST of which determines the quality of the material and is indicated by the following numbers:9128-2009, - was mentioned above. However, experts should also be aware of the composition. The coating has gravel or small crushed stone among the ingredients, which are crushed and are crumbs. The composition also contains sand.

As mentioned above, bitumen acts as a resinous product that holds the components together. However, for this, the material must be brought to a heated state. This also determines the technology of laying asph alt concrete. But today there is a technology that allows you to get bitumen with a viscosity of up to +5 °C. Oil is processed by modern methods, which makes it possible to obtain liquid bitumen that does not solidify to critically low temperatures. Usually this value is -30 °C.

The density of asph alt concrete (t/m3) is 2.35. But this value is not the only one that professionals should be aware of. For example, the mineral content is divided into three values:

• group A: 50 to 60% (rubble or gravel);
• group B: 40 to 50% (minerals);
• group B: 30 to 40% (rubble or gravel).

Crushed stone fractionation is regulated by technical specifications. In accordance with them, the material is made using crushed stone, the grain size of which can vary from 10 to 20 mm. This composition is used to form the top layer of the canvas. The technology is traditional and is used everywhere today, however, polymers can be added to the mixture.

Change of asph alt concrete under the actionmodern technologies

The density of asph alt concrete, according to state standards, should remain at the same level, but the quality of the material is constantly improving. This is due to the ever-increasing loads on road surfaces, which led to the search for modern materials to improve quality. As a result, it was possible to create cast asph alt concrete, which was discussed above.

It is used not only for construction, but also for road repair. This technology is regulated by state standards R 54401-2011 and involves the installation of a mixture without compaction. The temperature of the conglomerate in this case starts from 190 °C, an increase in this level increases plasticity. The composition is characterized by such features due to polymer additives.

Cast asph alt contains more bitumen, but the volume of minerals decreases. The content of crushed stone fraction up to 5 mm is from ½ of the total mass to 0%. The mixture is not as grainy, so it is viscous and does not imply compaction.

Additional ingredients

The bituminous binder improves the physical properties, so the material gives the coating high strength, wear resistance, integrity and long service life without cracking. The density of asph alt concrete remains the same, but for this it is important to follow the technology, as well as proportions. This is the vulnerability of the material, which distinguishes cast asph alt concrete. If a deviation from the norm occurs during the production stage, then the strength characteristics will suffer.

Conclusion

The advantage of asph alt concrete is also that it can be decorated. This greatly expanded the scope of its use, because with the help of the material you can decorate beautiful paths, sidewalks and alleys. Using this technology, colored asph alt concrete appeared on the roadway, which marks pedestrian crossings, markings and dividing lanes.

The technology involves the addition of colored 5 mm crushed stone, pigments and sand from granite, clinker, marble and limestone to the composition. To obtain asph alt concrete of bright colors, synthetic clarified bitumens are used. The technology increases the cost of coating, so it is rarely used.

But today I managed to find distribution in another way. It involves rubbing colored crumbs, while its addition during manufacture was abandoned. At the stage of laying the road, the addition to the top layer of the coating takes place.