The first asphalt pavement in the world. History of building materials

In which city did the first paved road appear?

Asphalt was the first oil product that man met. Natural asphalt - one of the types of natural bitumen - is a viscous resinous substance formed from heavy fractions of oil as a result of long-term weathering. It occurs in the form of reservoir vein deposits, as well as lakes in places where oil naturally comes out to the surface of the earth. It is a hard, fusible black mass containing 25–40% oils and 60–75% resinous asphaltene substances. The word "asphalt" (from the Greek "asfales" - strong, strong, reliable) has been known since the time of Herodotus, who described Mesopotamian and Persian asphalt deposits in his "History".
People found the use of natural asphalt at the dawn of civilization - in Ancient Egypt 5,000 years ago, the floors and walls of barns for grain storage were covered with asphalt. In Babylon, it was used as a binder when laying stone walls - the Bible says that "earth tar", as asphalt was called in ancient times, was used in the construction of the Tower of Babel. The same Babylonians, when constructing the famous Hanging Gardens of Babylon, used a layer of asphalt mixed with reeds for waterproofing. For 400-500 years BC in Media, the walls of fortresses, as the ancient Greek historian Xenophon testifies, were built of bricks held together with natural bitumen. In the same way, on bitumen, the first sections of the Great Wall of China were erected.
As for the road use of asphalt, which is more familiar to us, natural asphalt has been used in the construction of roads in America, for five thousand years. extra years before such use of asphalt was thought of in Europe and the USA. When in 1532 a detachment of Spanish conquistadors led by Francisco Pizarro entered the territory of the Inca Empire, they were amazed, among other things, by the magnificent roads covered with asphalt.
But the great civilizations of the past perished, and asphalt as a building material was forgotten for centuries and millennia. Up to early XIX centuries the streets of all cities in the world in best case paved with stones, and only then in large cities began new era the era of asphalt. In 1832 - 1835. in Paris, the first work was done on paving city streets and sidewalks with asphalt. Further, in 1835-1840, it was the turn of London, Vienna, Lyon, Philadelphia and some other cities.
IN Russian Empire The first experience of using asphalt was made in 1839, when in St. Petersburg almost 100 meters of a one and a half meter wide pavement near the Tuchkov Bridge were covered with it. On a somewhat larger scale, asphalt was used in 1865, when the terraces of the Winter Palace were asphalted. But already in next year asphalt began to be widely used on ordinary St. Petersburg streets, squares and courtyards, and by 1880 many streets in Kronstadt, Moscow, Riga, Kharkov, Kyiv and Odessa were covered with it. True, the first asphalt plant was built in Russia only in 1873, a few miles from Syzran, and before that, asphalt was purchased abroad.
Since the middle of the 19th century in France, the USA, Switzerland and other countries pavement are beginning to be made from bitumen-mineral mixtures. In the United States, cast asphalt prepared using petroleum bitumen was first used in 1876. Then, in 1892, the first road structure 3 meters wide was built using the industrial method, and 12 years later, 29 km of the road was built using a free-flowing asphalt distributor with hot bitumen.
The booming road network required new types of pavement, and asphalt proved to be the most suitable material. It can be laid almost perfectly evenly, it is a very quiet coating, but at the same time it has the necessary roughness. Modern roads are covered with asphalt, made on the basis of petroleum bitumen, obtained as a result of air oxidation of heavy oil distillation residues at a temperature of 239-340 °C. This process was developed in 1896 and put into production in 1914.

To the question Who invented asphalt? ? When did he appear in Russia? given by the author Neurosis the best answer is did he show up there?

Answer from electrostatics[guru]
Why do we need asphalt .... let there be a place on the planet free from bituminous tapes compressing the earth ....

Answer from Fitted[guru]
In the summer of 1839, sidewalks were covered in St. Petersburg for 45.5 linear fathoms 5 feet wide (97.08 × 1.52 m) and part of the bridge 8.5 long and 6.5 feet wide (2.59 × 1 .98 m) at the Tuchkov bridge dam. The first in Russia to establish the production of asphalt was engineer I.F. Buttats. The cost of 1 sq. m of coverage cost 14 rubles. For the first time, Russian asphalt began to be mined at the Syzran plant in 1873 (on the right bank of the Volga, 20 km higher than Syzran).
In 1876, the Moscow City Duma allocated 50 thousand rubles for an experiment on the installation of asphalt concrete pavement. Several sections of new material were built on Tverskaya Street

Answer from Liana Ceri[guru]
Asphalt (from the Greek asphaltos - mountain resin) - a mixture of bitumen (60-75% in natural and 13-60% in artificial asphalt) with minerals(limestone, sandstone, etc.). It is used in a mixture with sand, gravel, crushed stone for the construction of highways, as a roofing, hydro- and electrical insulating material, for the preparation of putties, adhesives, varnishes, etc. Asphalt can be of natural and artificial origin
a luchwe zaidi po ssilke,tam mnogo napisano ob istorii asfalta.udachi!
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Answer from Kitty[newbie]
no one is just an accident

Answer from Hanna[guru]
Asphalt (from Greek άσφαλτος - mountain resin) - a mixture of bitumen (60–75% in natural and 13–60% in artificial) with minerals (limestone, sandstone, etc.). It is used in mixture with sand, gravel, crushed stone for the construction of highways, as a roofing, hydro- and electrical insulating material, for the preparation of putties, adhesives, varnishes, etc. Asphalt can be of natural and artificial origin.
Natural asphalt is formed from heavy fractions of oil or their residues as a result of evaporation of its light components and oxidation under the influence of hypergenesis. It occurs in the form of reservoir vein deposits, as well as impregnated permeable layers (so-called acidification) and lakes in areas of natural oil seeps to the earth's surface (content in rocks from 2–3 to 20%). Solid black fusible mass with a shiny or dull conchoidal fracture. Density 1.1 g/cm3, melting point 20–100°C. Contains 25–40% oils and 60–75% resinous asphaltene substances. Elemental composition (%): 80–85 C, 10–12 N, 0.1–108, 2–3 O. Asphalt deposits are available on the territory former USSR , in Venezuela, Canada, France, on about. Trinidad and others. Mixing with mineral components (sand, gravel, etc.), it turns into a more or less powerful crust on the surface of large "oil lakes". Such asphalt is widely distributed in areas of shallow occurrence or outcrop of oil-bearing rocks and usually fills cracks and caverns in limestones, dolomites and other rocks. History-Natural asphalt is abundantly found in the excavations of the ruins in the vicinity of Babylon, where it was used instead of lime or cement when laying stone walls. Natural asphalt, or pitch, was also used by the ancients for pitching ships. Natural asphalt, also, according to the Bible, was pitched on the basket in which the mother put Moses, placing the basket in the reeds on the banks of the Nile River. Artificial asphalt or asphalt concrete is a building material in the form of a compacted mixture of crushed stone, sand, mineral powder and bitumen. Distinguish between hot, containing viscous bitumen, laid and compacted at a temperature not lower than 120 ° C; warm - with low-viscosity bitumen and compaction temperature of 40–80°C; cold - with liquid bitumen, compacted at ambient temperature, but not lower than 10°C. Asphalt concrete is used to cover roads, airfields, sites, etc. Initially, in the 19th century, city streets were paved with stones (cobblestone pavement). Starting from the middle of the 19th century, in France, Switzerland, the United States and a number of other countries, road surfaces are being made from bitumen-mineral mixtures. In 1876, for the first time in the United States, cast asphalt was used, prepared using petroleum bitumen. For the first time, asphalt concrete pavement was used to cover the sidewalks of the Royal Bridge in Paris in the 30s of the XX century. In the early 1930s, in France, in the department of Ain, sidewalks on the Moran bridge over the Rhone River in Lyon were covered with asphalt. The booming road network required new types of pavements that could be constructed as quickly as subgrades. So, in 1892 in the USA, the first road structure of concrete 3 m wide was built by the industrial method, and 12 years later, with the help of an asphalt distributor with a free flow of hot bitumen, 29 km of the road. Asphalt turned out to be the most suitable material for paving. Firstly, it becomes more even, and therefore less noisy and has the necessary roughness. Secondly, you can immediately open traffic on the laid asphalt concrete and not wait until it hardens, unlike cement concrete, which gains the necessary strength only on the 28th day. Thirdly, asphalt concrete pavement is easily repaired, washed, cleaned, any markings adhere well to it.

At the beginning of this summer, the State Budgetary Institution "Highway Roads", which serves a third highways capital has its own modern asphalt plant. This latest high-tech Benninghoven complex, developed in Germany, is located in the Biryulyovo Zapadnoye district - on the one hand, within the city (minimizing the path of cars to their destination), on the other, far from residential development. The new plant will allow not only saving budgetary funds, but also increasing the volume of asphalt mixes produced.

Let's study together the technology of asphalt production, the features of its laying, and what exactly the city benefits from the appearance of this particular plant.

2. The site for the enterprise was laid at the end of last year, and already in June two plants were put into operation, each of which can produce 240 tons of asphalt mix per hour (3 tons in 40 seconds). This performance is enough to roll up to 30 thousand square meters roadbed per day. Own asphalt plant is more profitable than contacting contractors, firstly it is always high quality products, secondly, the possibility of re-processing the finished mixture if the conditions did not allow it to be laid according to the technology (for example, the mixture cooled down on the way because the car got stuck in a traffic jam).

3. The composition of the asphalt mix includes 5 main components. These are crushed stone (left), screenings (essentially dust from crushed stone, in the center), sand (right), mineral powder and bitumen. The percentage of raw materials may vary depending on where the asphalt will be rolled. If this is a sidewalk (a zone with a minimum specific load), then the mixture contains the maximum amount of sand, and crushed stone is not used. If we are talking about roads (high load), then most of the asphalt mix will be crushed stone (the fraction is determined depending on the type and class of the road).

4. In addition to the usual granite rubble, a high-strength rock of volcanic origin is used - gabbro diabase. In total, there are three deposits in the world - in Australia, Ukraine and Russia. Raw materials are brought to the asphalt concrete plant from Karelia.

5. Mineral additives are needed in order to give certain properties to the finished mixture. For example, plasticity and resistance to temperature extremes. This is what distinguishes the technology modern production asphalt from how it was made before.

6. Bitumen - the main binding component. It enters the plant in thermos tanks in a heated form and is pumped into storage tanks, where it is constantly heated. Here it is worth noting the fact associated with the direct laying of asphalt on the road. Surely, many have noticed that freshly laid asphalt is not marked immediately, but after 2-3 weeks. This is not the laziness of road workers, but the observance of technology. After laying, it is necessary that the bituminous film evaporate from the top layer, otherwise the paint used for marking will firstly be painted, and secondly, freshly laid asphalt will have worse adhesion.

7. The plant works around the clock, therefore, raw materials are brought in continuously. At the entrance there are special cargo scales that weigh freight car first at the entrance and then at the exit.

8. The plant needs electricity to operate, diesel fuel and gas. The plant was built and launched in record time, but in Moscow it takes an average of one year to officially connect to city networks, so at the moment the plant operates completely offline. After the official connection diesel generators they will simply be transported to new sites under construction, so this option does not actually increase the cost of finished products.

9. Crushed stone, sand and screenings are loaded into receiving hoppers with a front loader. At the bottom of each bunker there is a damper, which determines the consumption of each of the initial components.

11. In the drum, the mixture is dried in a diesel oven.

12. And it is fed to the very top of the installation - into the screen, where the mixture is separated according to the granulometric composition.

13. This is necessary in order to accurately dose the composition of the finished product.

14. From heated thermos tanks, bitumen is added to the dry mixture.

15. And mineral supplements (stored in blue containers). One more important point. The photo shows the exhaust pipe ( of blue color) and you can even visually see that the exhaust air is clean. For comparison, you can look at the dust from the ventilation pipe of some other factory located in the background. Environmental regulations require emission measurements at a distance of 500 meters from the pipe, but this plant meets these standards even if measurements are taken directly on the territory of the plant.

16. After mixing all the ingredients, the finished asphalt enters the bunkers.

17. From where it is shipped to dump trucks. Despite the high sides, no more than 20 tons of finished asphalt are loaded into each truck. The temperature of the asphalt during shipment is 160°C, it must arrive at the site with a temperature of at least 130 degrees and be rolled at a temperature of at least 110 degrees. Depending on the outside temperature, this allows road repairs to be carried out up to 80 kilometers from the production site.

18. Control room - the control center of the entire installation. The operator clearly sees the whole process, and also manually controls the gate for the shipment of finished products. On the left screen, the work of scales and bunkers. On the right is the workflow in drying chamber, crash and mixing plant. In total, 80 people work at the plant, and for management production process 10 is enough.

19. After that, hot asphalt vehicles are also weighed on the scales and sent to the site. One more actual question Is it possible to roll asphalt in the rain? The technology does not allow asphalt to be laid in the rain, but since Since it is impossible to influence the weather, the decision is usually made locally. Before laying a new layer of asphalt, the base is spilled with a bituminous emulsion, and if the rain is not heavy, without the formation of puddles, then it is quite acceptable to roll the asphalt onto a wet base. As we remember, the asphalt laying temperature is above 110 degrees and all possible moisture from the base will instantly evaporate during laying.

20. The site now has two operating units that operate independently of each other. It is also planned to build another plant ( individual parts for her can be seen in the left upper corner). The administrative modular buildings are visible on the right side. There is also a factory laboratory that controls the quality of raw materials and finished products. So far, these are temporary structures, which will gradually be replaced by capital ones.

21. The State Budgetary Institution "Highways" also has a high-tech mobile laboratory. It includes a spatial laser range finder, six cameras and a georadar.

22. The Riegl VMX-450 rooftop installation is complemented by the Riegl VZ-1000 portable fixed station. These devices allow you to build a three-dimensional picture of the world. This allows you to measure the geometric dimensions of objects within a certain radius from the installation and automatically calculate the volume and area of materials or laid coating. It also allows you to fix defects in the pavement, curb stone And metal fences. Georadar allows you to determine the boundaries of the separation of environments and the location of communications. The most efficient travel speed for work is 40-50 km/h.

23. Factory laboratory in which they carry out quality control of raw materials and test finished products. The photo shows the DTS-06-05 machine, which is designed to test samples of asphalt concrete materials for compression and determine the tensile strength during splitting.

24. The test specimens are melted in a furnace, stretched, sieved, weighed, water saturation is determined, etc.

25. Any highway has a warranty period. For roads with increased traffic (for example, the Moscow Ring Road, the Third Ring Road, the Garden Ring and outbound highways), this is a 3-year warranty for asphalt pavement. For roads with less traffic and sidewalks, this period can be extended up to 5 years. If you see that the asphalt is changed every year, then this is exactly the case when the contractor completed the road with violations and is now redoing it at his own expense. Therefore, this is another plus to the fact that this asphalt plant belongs to the city - there is no point in producing low-quality products, because. then you have to redo it.

What is the result? The city and its inhabitants only benefit from the new asphalt concrete plant. Roads in the city are still maintained in good condition, but it will be even better.

It is a multi-component mixture based on sand, stone and bituminous binder. The “correct” name of the material is asphalt concrete, which does not prevent the use of the term “asphalt” even in specialized publications.

The composition of asphalt includes bitumen, sand, varieties of crushed stone or gravel, as well as mineral additives and fillers. Bitumen remains the only constant component, and the remaining components can be added in various proportions.

Functions of Fine Asphalt Mix Components

Sand, contained in the asphalt, plays the role of a filler and a shallow base, contributes to the distribution of pressure from the road to the ground. Without sand, the bituminous binder would flow out and crushed stone would be squeezed up.

In the case of special asphalts containing cement, sand is involved in the cementation process and gives the pavement additional hardness.

mineral filler- is a rock (sandstone, limestone or chalk) crushed to a dusty state, designed to fill residual voids. Sandstone is the most versatile, as it is inert to almost any chemical attack. Calcium carbonates (limestone and chalk) are commonly used on roads general purpose, while sandstone can be used near chemical plants.

Rubber- added to the asphalt in the form of rubber crumb (1-1.5 mm), gives the coating high water resistance and plasticity. Rubber-treated asphalts are much less likely to crack, which increases the time between repairs. The disadvantage of such roads is the high cost, so their use is limited to laying the most critical sections of highways.

Change in asphalt structure when mineral filler is added

Classification

One of the main parameters is the size of the crushed stone used, dividing asphalts into the following groups:

dense- are used for laying the top layer of the coating and contain fine gravel. In the case of a crushed stone fraction of less than 5 mm, such asphalts are used for pavements with low load (sidewalks and pedestrian crossings) and are called fine-grained. Larger fractions of crushed stone (5-15 mm) are suitable for creating the top layer of roads;
porous– are used in the lower part of the multi-layer pavement and contain less bitumen than dense asphalts;
highly porous- optimal as a basis for highly loaded highways. In their production, the largest crushed stone of a fraction of 15-40 mm is used. Such dimensions provide the necessary water permeability, creating drainage in lowlands and swampy areas. Larger size reduces the shift of the road base and indentation into upper layer soil, reducing the risk of washout and subsidence of the coating.

Manufacturing technology

The basis of any asphalt production lies in the preparation of the initial components, mixing at high temperature and storage in special heated bins.

The close location of the plant to the construction site is important, since the material must be transported for laying in a heated state. If the mixture cools, it will be very difficult to compact it, and the resulting coating will not be strong enough. Consider the stages of asphalt production.

Preparation of the components from which asphalt is made

This includes drying and sifting. Sand, crushed stone and rock usually arrive at the plant in a wet or air-dry state. The presence of residual moisture is fraught with a decrease in the strength of the coating and splashing of the hot bituminous mixture when water enters it.

To eliminate possible consequences, the material is dried at a temperature of 150-160 ° C - this temperature allows you to get rid of moisture adsorbed in the pores of the material.

Screening of crushed stone is carried out using a screen. The mineral filler is pre-crushed in a crusher, after which it is also subjected to fractionation. Depending on the production technology, drying can be single or double, repeated after crushing or screening.

Mixing components

Crushed stone and sand are fed to a belt conveyor, transporting them to a common bunker. Mixing with filler and bitumen can occur simultaneously or be carried out after reaching a homogeneous crushed stone-sand mass.

After adding bitumen, the temperature is maintained at the level of 160-170?C. After reaching the required consistency, the mixture (already asphalt) enters the storage bin, where it can remain heated for up to 4 days. During this period, it must be shipped to the consumer in order to avoid loss of strength characteristics.

Modification of asphalt with additives that give useful performance properties is carried out simultaneously with asphalt mixing. When creating a rubber-asphalt mixture, rubber crumb is added to a heated, ready-to-use product.

Delivery

Transportation of asphalt concrete to the construction site is carried out by road. Most often, ordinary dump trucks are used, which have a body that is resistant to hot asphalt. For transportation over long distances, kochers can be used - cars with special heat-saving containers. They are designed to preserve the properties of asphalt concrete for 2 days.

How asphalt is made at the factory and whether it is possible to do it yourself with your own hands will tell the video:

How to check the parameters of the roadway and raw materials for its production

To avoid purchasing low-quality asphalt concrete, you should ask the seller for a product conformity certificate. It is issued only after passing a set of tests corresponding to GOST or SNiP (depending on the scope).

In the market for quality control services, there are a number of regional laboratories that carry out sampling and testing asphalt pavement. During the study, an average sample is taken from the total mass of the material. The analysis of the roadway is carried out by examining the core, which is an asphalt rod obtained by drilling the road with a special hollow drill.

Cold asphalt do it yourself

Let's make a reservation right away that cold asphalt is only laid on its own, and its production is carried out only at the factory. The technology itself differs from the traditional coating in lower operating temperatures (70-110 °C) and the addition of a complex of protective and polymeric additives to its composition. The latter are necessary to give greater strength and the formation of a protective antioxidant film on the bitumen surface.

Despite the name, cold asphalt still has to be heated in cold weather to convert the bitumen into a plastic state. Together with this burner, you need to heat up the place where the asphalt will be laid. Depending on the manufacturer, it is possible to carry out work with cold mixtures even when negative temperatures(up to -20 ... -10 ° С).

The advantage of cold asphalt is a long shelf life. Unlike classic asphalt concrete, it does not need to be applied immediately after purchase. The disadvantages include lower strength, which is almost 2 times less than that of hot asphalt.

For tamping the coating, a vibrating plate or improvised means is used - thick wooden beam, car wheel. The final finishing of the surface occurs after repeated passage of cars. It is not recommended to make solid sections of the road from cold asphalt, as they collapse under pressure. vehicle weighing over 3.5 tons.

Modified cold asphalt:

Recycling of old asphalt

The high cost of creating a road makes it necessary to look for ways to save money. One of them is recycling - the processing of waste asphalt, in order to reuse. Processing is carried out in stationary conditions or in mobile recyclers.

The process is carried out in several stages:

removal of a layer of old asphalt - performed by a remixer that removes the roadway by milling;
crushing the milled layer to the size of crushed stone. The resulting product is called granulate and can be used for laying roads and preparing crushed stone-sand building mixtures;
heating in a furnace without direct contact with fire (to avoid ignition);
adding a fresh portion of bitumen and polymer additives, if necessary.

Recycling technology is of industrial importance and is usually used in the laying of urban and intercity highways. If there is an opportunity to buy recycling asphalt for private purposes, do not hesitate - there is no difference in performance properties, while the price will be significantly lower.

Mobile asphalt recycling plants

Installation #1 Installation #2

Modernization of asphalt concrete pavements

Despite sufficient practicality, roadbeds can be improved. One way is to use special mastics for asphalt. They include bitumen or bitumen emulsions containing rubber polymer additives.

Ordinary bituminous mastics are used in the hot state, and emulsions - in the cold. The principle of operation of mastics is to seal cracks and pores on the surface of the web. This prevents water from entering the road and its destruction - water contributes to cracking of the coating during freezing and water hammer during the passage of vehicles.

Advantages and disadvantages of the material

It is worth noting the following:

For light-duty applications, asphalts are not very expensive, unlike the multi-million dollar cost of laying highways;
With proper quality, asphalt is indispensable in any weather.
Numerous defects are rarely visible from the car window, which are clearly visible to pedestrians;
The production of heated and viscous mixtures is not an easy task, despite the automation of the process;
The difficulty of using heated mixes is partly offset by the appearance of cold asphalt;
Asphalt paths in the garden are not made precisely for a reason bad smell bitumen, although over time the mixture hardens and causes inconvenience only in the hot season.

Existing alternatives to asphalt are currently too expensive and not as practical. Unlike others building materials, the improvement of asphalt occurs not by the development of new materials, but by the modernization of old ones.

The widespread introduction of polymer modifiers makes it possible to fundamentally improve the properties of road surfaces and expand the limits of their technological application, which is confirmed by numerous tests of the material.

Asphalt is a natural or artificial multicomponent material based on surface (formed when it comes to the surface of the earth) or oil (obtained as a result of oil refining and subsequent processing of the tar remaining in the sediment) bitumen containing mineral fillers - gravel, crushed stone different breeds, sand.

In fact, the application of the term "asphalt" to road asphalt mixtures is incorrect. The content of asphalt as a mixture of bitumen in the total mass is several times less and depends on the grade of the material.

The beginning of the use of asphalt for road construction

The first mention of the use of natural asphalt for road construction refers toXVIcentury and South America. The production of artificial poured asphalt mixes appeared in the USA only at the end ofXIXcentury, bitumen-mineral compositions came to the streets of Europe a little earlier - in 1830-40. paved sidewalks and roadways in the cities of France, Austria, Great Britain and Russia began to be replaced with asphalt pavements.

The first trial and larger-scale experience of asphalting was carried out in St. Petersburg, but only by 1980. new road material has spread to other big cities. At the same time, its own plant was not built in Russia immediately - for three decades, the then progressive product was purchased abroad.

America again proved to be a pioneer in mechanized laying. It was here that an asphalt distributor was first used to build the road, from which hot bitumen poured.

The composition of natural and artificial asphalt

Natural asphalt is mined from rare deposits - Lake Peach Lake in Trinidad, the Dead Sea in Israel, Alberta in Canada, the Orinoco Belt in Venezuela, the US states, Iran, Cuba. The composition includes a mixture of bitumen with a content of up to 70%, inorganic inclusions and organic compounds.

Artificial asphalt mixes consist of two main components. Viscous, low-viscosity or liquid petroleum, modified bitumen and PBB (polymer-bitumen binders) act as a binder component. Crushed stone / gravel of different fractions from 5-10 mm to 20-40 mm, sand and mineral powder are used as fillers to improve strength, viscosity and fill voids.

Asphalt concrete is a monolithic road surface obtained by laying and compacting an asphalt concrete mixture.

Asphalt production technology

The main steps in the production of any asphalt mix are the preparation of components, mixing and storage in a bunker. Production is carried out on stationary and mobile (located near the site road construction) factories.

General technological steps:

Preparation of the mixture components. mineral fillers are crushed and subjected to separation into fractions using a screen, dried, heated, dosed and fed into the mixer.
bitumen preparation. The heated bitumen is fed to the bitumen melting plant, kept under constant stirring, adding surfactants and raising the temperature until the moisture evaporates, is sent to the working boilers and to the batching of the mixer.
Mixing components. Prepared crushed stone / gravel, sand are fed into a forced-action asphalt mixer for “dry” mixing with the addition of mineral powder and the subsequent addition of heated bitumen and mixing until a homogeneous mixture.
Overloading the ready mixture. Hot mix asphalt is sent to a storage bin or loaded into dump trucks for transportation to construction site. The cold mixture is cooled and transported to a warehouse for storage.

Heating of crushed stone and bitumen in the production of hot mixes is carried out to a temperature of 165 ... 175 0 С and 140…155 0 C, in the manufacture of cold mixes - up to 65 ... 75 0 С and 110…120 0 C respectively.

Classification of asphalt mixes is carried out according to residual porosity, type of mineral materials, their fraction and percentage, bituminous binder and laying temperature.

Separate types of asphalt concrete mixtures

In addition to traditional and widely used asphalt mixes, there are more advanced road materials, which differ from the first in composition and laying conditions.

These include:

Crushed stone-mastic mixtures of ShchMA with stabilizing additives.
Cast asphalt mixtures with increased content of bitumen and mineral powder.
Polymer-asphalt-concrete mixtures with the addition of polymers (elastomers).
Colored hot and cold mixtures with coloring pigments.
Glass-asphalt-concrete mixtures with the inclusion of glass cullet.
Rubber-asphalt-concrete and rubber drainage mixtures with crumb rubber and polymer additives.
Sulfur asphalt concrete mixtures with the presence of technical sulfur.

Each type of material has a specific area of application, due to the characteristics and performance and properties of the resulting coating.