What is the name of an unpaved road? Asphalt road laying process

To understand what percentage of wear is at the road surface, you need to understand the structure of asphalt pavements, as well as the purpose for which materials are used to seal and maintain wear resistance. Asphalt is the most optimal and widespread option for high wear pavements for roads, due to its practical and reliable properties. It is used for arranging sidewalks, access roads, parking lots, runways. With proper installation, such a coating can last about 20 years.

Components of asphalt

Asphalt pavement includes rock aggregate, sand, some additives, and petroleum-based liquid asphalt. The last component is a sticky black substance that serves as a binder in the asphalt road. Basically, the material has a viscous structure, but it is also found in a semi-solid form. Asphalt is also called bitumen.

The composition of the mixture is 90% sand and aggregate, and the remainder is asphalt or bitumen. Due to its viscous properties, the mixture perfectly binds the components from which the asphalt pavement is formed.

Strengths of asphalt:

• flexibility, thanks to which the surface adapts to changes in the external environment and weather;
• water repulsion. This property is essential, since the liquid negatively affects the paved area.

asphalt production

At the initial stage of asphalting the road, a dosing procedure is carried out. In this case, the chosen formulation of the asphalt composition matters. All components included in the asphalt mixture are weighed on a belt scale. This device allows you to weigh the materials and send them to a further stage of production.

The next production step is the drying of the aggregate. The operation is carried out in a special rotating drum at high temperatures (about 300 degrees). After drying, the aggregate changes its initial mass values, so the material is re-weighed. The aggregate must be screened and sent for storage in special bins.

At the third stage of production, the aggregate is transferred to the mixer and combined with a binder or liquid asphalt. The last components are stored in a tank, which is heated to provide a liquid consistency for easy mixing of the components. Asphalt is added to the aggregate mixer at set flow rates. Their calculation is based on the formulation of the asphalt surface. In the mixer, the components are mixed until a homogeneous mass suitable for forming a pavement for the road.

The finished mixture for coating is stored in special heated bins. Large enterprises have several large chambers in which manufacturers store asphalt prepared according to various recipes. According to the technology, it should be in the bunkers in a hot form until it is taken out for laying on the working area. From the moment the asphalt mixture leaves the plant, its required temperature is maintained all the time until the road is completed. Otherwise, it is not possible to roll the surface to a dense state.

Surface preparation and paving process

Before starting asphalting, preparatory work is carried out. When laying asphalt on an existing layer, it is necessary to prepare the soil for the asphalting process. This is a decisive action in matters of practicality and long service life of the road surface.

Preparatory activities include:

• proper cleaning;
• complex earthworks;
• soil compaction;
• the device of gasket materials, they contribute to the durability of the coating.

From gasket materials, a bituminous base prepared according to an individual recipe or rammed stone is used.

Before applying the asphalt mixture to the prepared area, including the existing asphalt pavement, prepare the base. A thin layer of hot sticky bitumen is sprayed with an asphalt distributor. Thanks to this action, a strong bond is achieved between the asphalt and the base.

The asphalt paver is responsible for the distribution of the mixture over the working area, as well as its laying and rolling. To achieve the optimal degree of compaction of the asphalt mixture, special rolling techniques are used, which ensures the high quality of the future road. Good compaction of the asphalt mixture is achieved with the correct weight, which is calculated based on the thickness of the layer.

After rolling, the asphalted road is left until completely cured, this process takes at least a day. Only then can the surface be used for its intended purpose. If you do not meet the deadlines for rejection and start premature operation, the road will subsequently quickly fall into disrepair.

Upon completion of the paving, rolling and curing of asphalt, the pavement will have to pass the test of time and external factors. During operation, the road is subjected to mechanical influences, weather changes (rain, snow, heat, cold), which eventually leads to gradual deformation, cracking and other damage to the asphalt pavement.

To significantly extend the service life of the road and maintain it in good condition will help timely specialized maintenance of the paved area. The complex of measures is to eliminate the resulting cracks, pits, potholes. These road repair and maintenance practices aim to protect against damage and extend the life of asphalt surfaces, thus avoiding premature replacement of the entire surface area. The application of a wear-resistant layer is carried out on existing old asphalt surfaces, as well as at the initial stages of road construction.

Game - lotto for schoolchildren

Playing loto will help the children think together, make decisions, and make choices. The competitive spirit of the game arouses interest and stimulates creativity. The game can be played many times, and each time the hosts-organizers prepare prizes, develop new topics, distribute roles.

Decide how many teams will be in the game. For each group, copy the cards and prepare a lotto card: divide the A4 sheet into 24 cells and mark them with numbers, highlighting the numbers or individual cells of the corresponding level of complexity of the questions with color. Give each team a packet of answer cards. Remove some answers.

Structure of answers: correct (18-20); wrong (10-20); some answers are not present at all (4-6); blank cards for their answers (5-7).

Game order

1. The facilitator slowly reads the question, clearly naming its number. Thinking time is 30-60 seconds. To designate a time interval, you can use: a musical passage; metronome; hourglass, etc.

2. The team chooses an answer, if it is not in the bag, they write their own on a blank card and put it in the appropriate box on the Lotto card. (You can agree to play 24 questions, or 18, or 15 ...)

3. After reading all the questions, at the request of the players, they repeat unsolved and difficult questions.

4. Announcement of answers. The facilitator reads the question and then (each time in a different order) asks the teams (by naming the team number or pointing by hand in turn) to show their answers. Then he says the correct answer. Teams with incorrect answers turn over the card.

Summarizing

Option 1. The facilitator asks the teams to announce the number of incorrect or missing answers. The best teams are determined by the smallest number of them.

Option 2. Subject to special training on the topic, all questions, depending on the level of complexity, can be located in cells of different colors. For example, the most difficult questions are marked in red and the answer to them is defined as 4 points; less complex - in blue (3 points); the next level is green (2 points); the lightest are white (1 point). Representatives from the teams can sit at a special table and record the answers of the teams during the game (each representative follows the opposite team) when the leader announces the correct answer. At the end, the points of the correct answers are calculated.

Lotto "THE WORLD AROUND US"

1. What is the key decoration called?

2. What is the name of the front outer wall of the building?

3. What is the name of the huge space rock?

4. What is the name of the vast sandy area?

5. What is the name of the "clothes" for the pillow?

6. What is the name of a long artificial corridor in a mountain?

7. What is the name of the "clothing" for lamps?

8. What is the name of the wall image of small multi-colored pebbles?

9. What is the name of the stone ledge along the paved road?

10. What is the name of a large container for liquids?

11. Who is called a sister-in-law?

12. What is the name of a wireless one-way communication device?

13. If there was frost, then in the morning it will be ...

14. “I lead my granddaughter by the hand through all the rooms” (riddle).

15. “In the house, the room walks, surprises no one” (riddle).

16. What is customary to take with hands from a common plate?

17. What is an ex-libris?

18. What is the name of a dish of mashed or pureed vegetables or fruits?

19. What takes longer to cook - semolina or rice porridge?

20. What is the name of the astronaut's suit?

21. If you have a canvas depicting birds or animals in front of you, then what genre of painting would you attribute it to?

22. Two sausages are boiled for 6 minutes. How long will eight sausages cook?

23. What are the names of mushrooms that come in different colors?

24. What is the name of a handwritten commemorative signature?

Road communication is the most important part of the economy of any country, because it plays an important role in the level of development of industry and production of the state. And the roads of Russia in this regard are no exception. In order to determine the level of quality and trafficability, a list of specific requirements for roads has been developed. Those of them that meet the criteria as fully as possible are able to receive traffic flows of any complexity and completeness and facilitate the delivery of passengers and goods in all directions and at any distance. That is why it is worth paying close attention to the question of which categories of roads generally exist and how they are classified.

How it all works

In order to increase traffic safety and increase cross-country ability, a modern highway is being equipped as a complex technical structure and is being built on a specially allocated area of ​​land, called the right of way. There, the roadway itself is equipped, along which vehicles move. To ensure increased throughput, driving comfort and traffic safety, almost all types of roads are equipped with a hard surface: asphalt, concrete, and other building materials. The width of the carriageway for a single-lane road is at least 7 meters. At the same time, a small part of the right of way does not have a hard surface and is not included in the roadbed - it is used as an additional area. Detours, bicycle paths are laid here, and this part of the road is also reserved for the movement of tractors and horse-drawn vehicles. In addition, drainage and forest protection structures are being built in this part of the right of way, and building materials are immediately stored during the repair of the road surface.

In addition to the carriageway, the roadway also includes two shoulders - to the left and to the right of the carriageway. These additional lanes serve as an exit (both accidental and forced) from the main part of the road, and can also be used as an auxiliary lane for passing or repairing the road surface. Different types of roads have shoulders of unequal width: from 2 to 3.75 meters. To drain water from rain and snow, ditches are arranged on both sides of the road - ditches with a depth of 0.3 to 1 meter. Regardless of the class and category, all road surfaces are not made flat, but in the form of a gable roof with an inclination angle of 1.5 to 4 degrees. This allows rainwater not to linger on the canvas, but to flow freely into the cuvettes.

different categories

• E - overpasses of European importance;
• M - routes of federal significance;
• R - roads connecting administrative centers;
• A - federal and regional roads, entrances to the largest transport hubs - airports, sea and river ports;
• K - regional roads;
• H - other roads of local subordination.

There are also several more criteria by which roads for various purposes can be classified:

• by the width of the coverage and the number of lanes;
• according to the principle and method of crossing with different types of roads;
• by the presence or absence of markings and a dividing line.

It is the last dividing principle that tells whether the road is active, whether it intersects with other roads and how many times, how traffic is regulated, how many turns it has and other parameters.

Principles of classification

Basically, all roads are classified primarily on the basis of how traffic is carried out and how easy access is provided to them. If we consider the categories of roads from this position, we can distinguish 3 main classes:

• motorway;
• highway;
• ordinary road.

Each of them has its own subclasses, that is, it is divided into types depending on the geographical location:

• regional;
• regional;
• territorial;
• regional;
• national;
• international communication;

Of course, such a division is rather arbitrary, but in practice everything is somewhat more complicated. The fact is that each country accepts its own categories and signs of division - in Russia, for example, there are five categories of roads, and in Ukraine - only four.

The first category of roads in Russia includes highways, expressways and motorways. Such overpasses have a width of at least 15 meters and are equipped with a dividing strip. In each direction, there are at least two traffic lanes, with a width of at least 3.75 meters. Such roads are designed for high traffic volumes and are equipped with high-quality concrete pavement that can withstand a large influx of vehicles. The capacity of such overpasses exceeds 7,000 vehicles per day, while vehicles move at a speed of at least 120 km/h.

Second

The second category of roads includes highways equipped with asphalt coating and connecting industrial, cultural and administrative centers of the country. For such overpasses, a width of at least 7.5 meters is provided, and a throughput capacity of more than 3-3.5 thousand cars per day. At the same time, the speed of movement is also maintained at the level of 120 km / h.

Third

The third category of roads includes routes with a much less intense traffic load, no more than 3,000 cars / day. Such roads can have a width of 3.5 to 7 meters, and the road surface on them is equipped according to light requirements, it can also be cobblestone. The speed of movement on such roads usually cannot exceed 100 km / h, and vehicles with a load of more than 6 tons are not allowed to travel on them at all.

Fourth and fifth categories of roads

The fourth category of roads is distinguished by the presence of a rather poor quality pavement. Because of this, movement along them can be very difficult, especially in the autumn-spring period. Such roads can pass no more than 1,000 vehicles per day, and the speed limit on them is 80 km/h. Heavy-duty vehicles, on the other hand, are most often completely closed on such roads, this is due to the fact that the movement of heavy vehicles leads to rapid and serious destruction of the road surface.

A prominent representative of the fifth category is the "classic" country road. Roads of this category most often do not have any coverage at all, and it is unlikely that it will be possible to move along them at a speed exceeding 60 km / h.

Forest roads - classification

A separate type of classification can be called the purpose of roads. Forest roads are a separate type of roads in Russia. As the name already implies, they are settled in forest areas and serve for trouble-free transport access to these parts of Russia.

Forest roads can also be divided into several types depending on their functional purpose:

• forestry - designed to monitor the state of forests, it is through them that rangers bypass the territories entrusted to them;
• logging - provide transport links when felling forests for industrial and sanitary purposes; since heavy freight transport moves along them, they are additionally strengthened to ensure increased cross-country ability of heavy vehicles;
• fire-fighting - designed to provide access for fire brigades to the sources of probable fires;

In the old days, one more type of road could be added to this list - the plank road, but now they are practically not built, and the old ones have long fallen into disrepair. The fact is that the roadway in this case is a flooring made of solid logs. It is possible to build such a road quickly, but it is impractical - after all, wood is now not cheap, and a lot of it will go to such a path. And the service life of such a coating, compared, for example, with asphalt, is small, the wood quickly rots and deteriorates in adverse weather conditions.

How important is road repair?

As you know, not all highways in Russia can boast of a new high-quality coating, but this is one of the most important factors that should not be neglected. Quite a lot depends on the quality of the road surface, because in order to ensure a quality human life, cargo transportation (not to mention passengers) must be carried out as quickly, safely and efficiently as possible.

Often, the discrepancy between the road surface and the requirements of modern transport realities and the ever-increasing traffic flow can lead to many negative consequences: an increase in the number of accidents, accelerated wear of vehicles, excessive fuel consumption, a decrease in traffic speed, and many others. It is even scary to imagine that, for example, someone's life may depend on which particular road this or that medicine will be delivered, or how quickly a fire truck can arrive. So the road surface also plays an important role in the classification.

Classification of roads depending on the surface

Depending on the type of road surface, the following types can be distinguished:

• bridges;
• cement concrete;
• covered with gravel or rubble;
• ground;
• tar concrete;
• asphalt concrete;
• coated with materials containing organic substances having astringent properties.

Summing up the foregoing, we can once again note the importance and necessity of all work related to the arrangement and repair of expensive, as well as maintaining them in good condition. New technologies open up a lot of opportunities to ensure that both the country road and the highway remain at a decent level in terms of strength and quality of the pavement and are able to provide high vehicle traffic.

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 5000 years ago, the floor and walls in barns for storing grain 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 was used in the construction of roads in America, more than half a thousand 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. Until the beginning of the 19th century, the streets of all cities in the world were at best paved with stones, and only then did a new era begin in large cities - 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 the Russian Empire, the first experience of using asphalt was made in 1839, when in St. Petersburg they covered almost 100 meters of a 1.5-meter-wide sidewalk near the Tuchkov Bridge. On a somewhat larger scale, asphalt was used in 1865, when the terraces of the Winter Palace were asphalted. But already 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, Kiev 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, road surfaces have been 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 needed 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 residues of oil distillation at a temperature of 239-340 °C. This process was developed in 1896 and put into production in 1914.

The asphalt road has long become a familiar part of the modern landscape, which few people pay attention to. A network of roads stretched across almost the entire earth's firmament, improving the speed of communication between people. Watch how, for example, they pave the road. On the one hand, such work can hardly be called high-tech. On the other hand, knowledge of some of the nuances in the creation and operation of modern roads contributes not only to their strength and durability, but, in some cases, directly affects safety while driving.

A small digression into history

Asphalt has been known to our ancestors since ancient times. For example, the Dead Sea was called asphalt, and this name has survived almost to this day. The deposits that were there were used not only for road construction, but also in shipbuilding and even mummification.

It is especially interesting to note the Spaniards, who drew attention to the excellent properties of the bituminous lake Peach Lake, that the natural asphalt mined in this place is still popular all over the world. Scientists have estimated the needs of mankind that this lake can provide at about 400 years, but there are 15 more deposits. The cover of the Paris Royal Bridge can rightfully be considered the first paved road. In its creation, a bituminous-mineral mixture was used. "Fashion" has come to Russia. So, in St. Petersburg, several road sections were asphalted. But the Americans really turned around starting in 1876.

Where does the road begin?

In what order will the road be asphalted? Of course, it all starts with planning and design. They take into account the interaction with other roads, drainage systems, traffic lights, crossings and many more nuances.

Preparation

This is perhaps the most time-consuming and responsible operation of the process. The quality of an asphalt road directly depends on the correct decision-making and control over the execution of preparatory work. According to their specifics, preparatory measures differ depending on environmental conditions. In the city, they may not be so labor-intensive, but outside the city there are options: studying the presence of groundwater and other factors. For example, if you do not take into account the occurrence of groundwater, then an asphalt road can be washed out and a collapse will occur.

The process itself is as follows: depending on the terrain conditions, sand is added or, conversely, the excess earth is cut off with a bulldozer. The next most important point is to give strength and hardness to the foundation for the road. There may be several options. Crushed stone is poured with sand, and the fraction of crushed stone matters. Large crushed stone is used where a serious load on the road surface is expected, small - on the contrary. Sometimes reinforced slabs can be used.

Side curbs serve several purposes at once: they hold the roadway together, and they also serve as a guide in its creation. After filling the "cushion" of sand and gravel, it must be tamped. It is impossible to carry out such work carelessly, since the quality of the asphalt road depends on the strength of the base.

The moment of acceptance of the work performed

And here comes one of the most important moments - the acceptance of hot asphalt. The very base of the road is properly cleaned before this and spilled with hot bitumen, which is rubbed over the entire area. The arrived hot asphalt usually falls out into one heap and is evenly distributed by hand with shovels over the entire area of ​​​​the future coating. Following the road workers who distribute the asphalt, there are people with an interesting tool that vaguely resembles a mop, or, as the builders call it, a “mashka”. Their task is to level the laid asphalt as much as possible.

The final chord is the paver, which slowly but surely completes this production process. This is a description of the manual way of laying asphalt. There is a second, no less effective, with the participation of two special road-laying machines. The first distributes asphalt, replacing all manual labor. The second is the paver, which, following the first, brings the work to its logical conclusion.

Some Observations

Watch how the roads are paved. Sometimes you can see very interesting things. For example, when laying occurs in rain and severe frost. Because of this, the quality of asphalt deteriorates sharply, because it is impossible to do such work in bad weather.

Heavy trucks break roads mercilessly, especially in cities where the paved road is not designed for such a load.

And, as they say in medicine, prevention and prevention are better than long and exhausting treatment later. This statement is also true in relation to the rules for the operation of the road surface.