At first glance, the construction of a new highway seems to be a fairly simple task. To be honest, few people know who is working on the construction of roads, and what the planned amount of work needs to be done when the highway is being laid. Many people think that the main work is asphalting the road surface. This is not true.

Who builds roads?

The organization that is directly involved in the construction of the highway is called the general contractor.

The workers of the road construction team perform earthworks: leveling the soil, laying a layer of sand, a layer of gravel and crushed stone.

Without specialized equipment, road construction would be unrealistic. In road construction, various drilling machines, excavators, bulldozers, tractors, asphalt pavers and uprooting machines are used.

How are roads built?

Before a new freeway can be built, it must be designed. The duties of engineers include predicting the composition of the traffic flow (trucks, cars and buses) and the intensity of the traffic itself on this road. Thanks to the results of the forecast, it will be revealed how wide the future road will be, respectively, the number of lanes, as well as the thickness of the asphalt pavement layer and the base layer.

The surveyor must obtain information about land work. Work on the motorway will be carried out where the amount of earthwork will be minimal. The surveyor must take into account the soil composition. If loamy and clayey soils prevail at the site of the highway, then these types of soils will be very mobile in spring, since the soil is oversaturated with moisture.

After the design phase, the construction phase begins. The terrain on rough terrain is the most acceptable, because the soil that is in the hills is moved to the lowlands. The profile of such a pavement will contain a much smaller difference in elevation, and the cost of moving the soil will be minimal.

What materials are used in road construction?

After leveling the earth cover, lay out a layer consisting only of sand. Such a layer provides greater stability and immobility of the future motorway. Road builders lay a layer of sand because it has high performance in high humidity. It is the least subject to shifts when wet and when exposed to landslides. Sand is well compacted and laid with the help of equipment.

After a layer of sand lay out a mixture of gravel and sand. A layer of rubble is laid on top of this mixture. This strengthens the base. Crushed stone consists of stones that give the base the necessary hardness and strength. As well as a layer of sand, layers of gravel, sand and crushed stone are subjected to dense compaction.

Asphalt concrete pavement should have two layers. The bottom layer consists of large particles, and the thickness of this layer is 10 centimeters or more. The top layer of the asphalt pavement has a thickness of 5 cm. The top layer provides protection for the bottom layer and low noise. The upper layers of pavement are reinforced with a geogrid made of different types asphalt concrete.

According to the editors of the site, the process of building roads is very complicated, in which each stage must be carefully worked out so that there would be one less problem in Russia.
Subscribe to our channel in Yandex.Zen

Construction work is carried out almost continuously day and night. Everyone has probably seen more than once how builders put asphalt on roads, but they hardly thought about what the whole process of building a road is like.

The first stage of any construction (or reconstruction) is design. Then held geological surveys, which determine the relief of the territory, the composition and properties of the soil, the state of soils, atmospheric air, surface waters, etc. Based on these data, a road construction plan is being developed.

Further construction work can be conditionally divided into the following stages:

• preparatory work (cutting down trees, dismantling fences, etc.)
• excavation(export or import of soil, strengthening subgrade, construction of earth embankments, etc.)
• laying new or re-laying existing engineering communications falling within the construction zone
• arrangement of the bases of the "road pie" (device of the underlying layer of sand, "filling" the base of crushed stone or concrete)
• asphalt paving
• landscaping of areas adjacent to roads (marking, installation of fences, road signs, curbs, storm sewers, road lighting, etc.)
• environmental protection measures (replacement of windows in those located near the road residential buildings, installation of noise barriers along the road)

One of the most important elements of road construction is asphalting, when an asphalt mixture is distributed on a prepared subgrade base (stone or reinforced concrete “skeleton”), then it is “trampled down” - and the road is ready. The service life of the road largely depends on how high-quality this mixture will be and how professionally the work will be carried out. After all, it is not by chance that the top layer of the road surface is called the “wear layer” - every day a huge mass of passing cars presses on it.

Asphalt laying can be made from various materials: asphalt concrete, poured asphalt, crushed stone, crushed stone impregnated with bitumen, gravel or impregnated soil, etc. Often, bitumen or so-called secondary building materials are used in the construction of roads: asphalt chips, broken bricks and asphalt chips.

The most common building material is asphalt concrete. Asphalt concrete is crushed stone, sand, stone flour and actual molten asphalt mixed together. This "stuffing" is laid out on earth foundation in several layers. By the way, it is because of the multi-layered nature of the roadway that it is often called the “road pie”. The number of layers depends on various factors, but above all on the expected traffic load.

Larger gravel is placed in the lower layers of the "pie" so that the road is strong, stable, and durable. And smaller crushed stone is poured into the upper layers - this gives the road surface such qualities as high wear resistance and water resistance. In addition, due to the presence of small gravel, the road surface is somewhat rough, and this is necessary so that the tires of the cars do not slip.

Another type of asphalt is the so-called cast asphalt. It is a mixture cooked at very high temperatures. The viscous-fluid mixture is brought to the construction site in special containers that keep the temperature, and the hot mixture is poured into the place of the future road. A road made from such asphalt can withstand heavy traffic loads, resists wear and tear and the effects of studded tires and anti-icing agents. In addition, poured asphalt absorbs noise well.

Asphalt is laid with the help of special equipment - asphalt pavers. The roller compacting the asphalt makes the road surface even and strong. By the way, there is such a kind of skating rink as a vibratory skating rink. Its constant vibration gives additional "tamping", and the asphalt becomes even more dense and durable.

Road construction is constantly being improved. New technologies are improving the composition of the asphalt pavement, making roads even safer and more durable. To be included in the composition of asphalt, special components are being developed that improve the grip properties with automobile wheels - on such roads, drivers are not afraid of rain or light icing. New modifiers for bitumen allow asphalt concrete not to crack at sharp temperature fluctuations. Such a modified bitumen, combined with granite fillers and special additives, will protect the coating from the "whims of nature" when the roads either freeze or thaw, from which their quality deteriorates.

According to the standards, pavement should serve without repair from ten to eighteen years. Surprised? According to the head of Rosavtodor, Roman Starovoit, Russian road builders give a guarantee for coverage from four to eight years, but within twelve years they are obliged to eliminate emerging defects at their own expense.

They can significantly increase the service life of roads - but are they applicable here?

Tire by tire

The most interesting and useful -. For example, the composition of the so-called rubber asphalt includes crumb rubber obtained from old tires. Such asphalt is suitable for any climate, provides excellent grip, reduces braking distances by 15%, reduces noise, withstands heavy loads and is not prone to rutting. It is also extremely important that it allows you to solve one of the environmental problems by recycling old tires, of which about 300 million accumulate annually in the United States alone!

In America, this has been used for three decades. A little less - in Europe and Israel, where they are also very concerned about environmental issues. However, until now, hardly a tenth of the worn-out tires are used for road construction. The reasons are the complication of asphalt production technology and the increase in its cost. But the main obstacle is opposition from the lobby of traditional asphalt producers. And we looked closely at rubber asphalt, tested it, but the results were considered ambiguous and a wide road was not opened for this material. I would like to believe that for the time being. To begin with, we need to learn not to scatter old tires on garages and roadsides, but in a civilized way.

However, Unirem, a modifier of asphalt concrete mixtures, obtained from old tires, is already widely used. According to the developers, active (with additives) rubber powder increases the durability of the road surface by 25%, reduces rutting by half and does not require changes in the asphalt concrete production technology. However, asphalt with a modifier, which the wits have already called "nano-asphalt", requires impeccable adherence to the laying technology. Otherwise, the road becomes covered with blisters and it becomes impossible to drive along it, as happened in Ufa and Irkutsk. A reverse example is the M10 Rossiya highway (386–388 km, near the roadside complex Polputi), where the nanoasphalt has been lying since 2005, not requiring replacement. But every day thousands of cars and heavy trucks pass through this area.

The Americans also suggested laying old tires in the base of the road. Sidewalls are cut off from the tires, fastened together to form a grid of round cells, and crushed stone is poured into them. This technology provides significant strength of the base and reduces the cost of construction by half. But it is unlikely that it will find application in Russia in the near future - for the reason mentioned above.

But since 2014, Russian road builders have been using the American word superpave (in translation - super coating) - this is the name of the method of volumetric design of asphalt concrete, which allows to improve its quality, use local materials without reducing the wear resistance of the coating (for example, a stone going into asphalt concrete may be inferior in density to stone from another area). Superpave makes it possible to design the composition in such a way that the strength characteristics of the road surface will correspond to the specified ones - and complex logistics and additional costs will not be required.

If only you knew from what rubbish ...

Two years ago, a 122-kilometer expressway was built in the Chinese province of Shanxi, using 6 million tons of construction waste to build it. Thanks to this, the Chinese saved about $47 million, 3.4 million cubic meters of sand, 32 tons of coal and, very importantly, 200 hectares of land that would be required for waste disposal. We also use construction waste - a kind of "barbecue" from pieces of concrete strung on reinforcement, but such "roads" are unsuitable for passenger cars. They are constructed as temporary during construction. And if they were filled with asphalt concrete, which can also be made from recycled materials, the road would be quite suitable for mass exploitation. After all, there are road surface regeneration technologies that allow using a significant part of the old asphalt concrete mix for the production of a new one (primarily in the factory, after remelting).

Cold recycling technology is even more interesting and environmentally friendly. Old asphalt is cut off, crushed into crumbs and, mixed with a new binder, a new coating is made right on the road. In 2014, this technology was demonstrated to the head of Rosavtodor in Khabarovsk, and now Russian road builders are ordered to use old asphalt as much as possible - this way they can save up to 40% on materials. Today in Russia, some companies are repairing roads using cold recycling technology, but so far this is the exception, not the rule.

Dutch company Royal VolkerWessels

StevinN. V. A couple of years ago, she unveiled the Plastic Road () project - she proposed to make a roadbed from cast plates, connecting them end-to-end, like parts of a children's designer. The principle is not new; the so-called concrete blocks are built in the same way. Only the Dutch offer to cast slabs not from concrete, but from plastic obtained from the processing of waste caught in the oceans - bottles, bags and other rubbish.

Plastic roads can also replace ordinary asphalt roads by removing all the upper layers and leveling the base. With proper installation, an almost perfect surface with inconspicuous joints is obtained. Damaged segments are easy to replace, and since the slabs are hollow, electrical cables and communication lines, sewerage and gas mains will be placed inside. If necessary, you can even make heating.

But in Russia, according to experts, this technology is unlikely to take root. If only because they are prohibited in the Netherlands, and in our country they are widely used. In addition, according to the head of the metropolitan testing laboratory building materials Rauf Yusifov, a plastic coating, even in summer, is not able to provide a coefficient of adhesion sufficient for safe movement, not to mention winter: “Macroroughness can be created by forming longitudinal and transverse grooves that will be under the wheels, but the microroughness necessary to remove film water is artificial not create." Yury Vasiliev, professor of the Department of Road Construction Materials at MADI, speaks in the same vein. He also recalls that household waste is still not sorted and it is difficult to separate plastic waste from other waste. And to use new plastic for the production of road slabs is too expensive.

Plastic coating can only be used on sidewalks, footpaths, alleys, on the roadway with a longitudinal slope of not more than 20% and low speed (up to 40 km / h). That is, in parks, not on highways.

However, we already use plastics in road construction, and in such a volume that other foreign road builders will envy. For example, for the construction of electric lighting masts and their supports, noise barriers, bridge crossings. Composite materials are used for formwork, prestressed reinforcement, railings, shields, luminous paints based on phosphors.

Dreams Dreams

In the Netherlands, road builders dream that it reacts to temperature changes - this is already being tested on one of the routes in the south of the country. The British dream of a marking that accumulates energy during the day, and at night it glows the more, the darker the night. There is the idea of ​​smart roads that warn drivers to slow down by lighting signs on the pavement when a pedestrian or animal steps on it. Many people dream of roads with built-in solar panels: the energy accumulated by them should be enough to light the road, and even for contactless recharging of passing electric vehicles. For example, in the state of Idaho (USA), a road surface was created from solar panels that can withstand trucks weighing up to 115 tons.

To defeat the mudslide near our own dacha, we build and strengthen the road with our own hands

About two notorious Russian problems heard by many. And if it is practically useless to fight one of them, then the second, concerning the lack of roads, can be completely solved on your own. This is very important on a relatively small scale, related to their own suburban area and the territory adjacent to it.

In this article, we will consider ways that, with some effort, will strengthen the road, make access roads to the suburban area with our own hands.

Dirt road dimensions

The width of a public dirt road must be sufficient to allow two vehicles. Ideally, it should be 4 ... 5 meters. If the road leads directly to the gates of your dacha, and only you will use it, then 2 meters wide will be enough for such a dacha path.

How to build a road with your own hands: an economical option based on crushed stone and slag

To begin with, a little advice: if you don’t want the construction of the road to fall completely on your shoulders, and after that it would be used by everyone who is not too lazy, it would be right to unite with your neighbors before building a primer and share financial and related construction costs with them. expenses.

In order to get rid of dirt and slush, it is enough to cover the access roads with crushed stone, gravel, slag or asphalt chips. According to the experience of numerous builders, this option is quite practical, especially if it is correctly implemented.

Here is what one of the users of our forum writes about a similar method of arranging a dirt road.

PiZZa

My experience of building a road without the use of nanotechnology. 30-40 meters to the site really lay through the swamp, which dried up at least by July.
How was my road to the site done with my own hands:

• A ditch 1 m deep was dug along the road section - an excavator (700 rubles);
• The soil spilled onto the road;
• One and a half KamAZ large buta (I was lucky - curbs were changed in the city - almost a freebie) - 3-4 tons R;
• 3 KamAZ asphalt chips - 12 tr.

Total, approximately, 16 tr. The road turned out no worse than in the city. The observation period is 4 years. No changes were noticed. Is it just a small track from heavy equipment and bumps from the uneven distribution of asphalt.

But this special case. To create a cheap dirt road with your own hands, there has long been a reliable and time-tested technology, and in most cases it will be correct to use it.

The construction of such a road is carried out in a certain sequence. First of all, a fertile (vegetative) layer 25-30 cm thick is removed from the soil surface. This is done using a grader or other specialized road construction equipment.

The result is a kind of trough, the bottom of which should be made in the form of a gable profile. This is done to drain rainwater from the roadway into small ditches formed along the edges of the future road.

The bottom of the profiled "trough" can be compacted with a soil roller, after which a sand cushion should be created on its surface. It is designed to improve the drainage quality of the future road. The thickness of the sand layer should be 15–20 cm. The sand should be compacted and a layer of crushed stone should be laid on top of it. Gravel, slag or asphalt chips can also be used as a top coat. The thickness of the top layer should be within 20 centimeters - in the middle of the road and about 10 cm - along its edges.

Layers of sand and top cover should be made in the form of an embankment and ensure that these fractions do not fill up the side drainage ditches.

How to strengthen the road in the country

After the implementation of the above measures, the dirt road to your suburban area can be considered ready. It remains only to compact its surface with a roller or, in extreme cases, with a truck that was used to transport gravel. This type of ground cover, although relatively reliable, can be called into question (especially under intensive operating conditions) and will soon require repair. Here is what our forum member says about this.

mother FORUMHOUSE User

Crushed stone fraction 40-70 10 cm after spring went into the ground, I am watching the second season. It's the same with secondary rubble. The car does not get stuck, but the soul is no longer happy, it's dirty on foot.

At FORUMHOUSE you will learn how to do it yourself and who should pay for it in a holiday village.

Conclusion: in order for bulk coatings not to spread over time, and their layers to be clearly separated from each other, it is correct to use more advanced, but also more expensive technologies. They require the use of materials such as geogrid or volumetric geogrid.

How to build a dirt road - we use geotextiles

Geotextile (doronite) is a special synthetic fabric used in road construction to separate bulk layers. It has high strength and freely passes moisture. If the future road is based on solid and stable soil, then its construction can be dispensed with using geotextiles and bulk materials listed in the previous chapter. The geotextile is spread on clean and compacted soil, after which it is covered with a layer of sand and gravel (crushed stone, slag or asphalt chips can be used instead of gravel). This avoids mixing of the bottom soil with the bulk layers. As a result, gravel will not mix with mud, and the road is guaranteed to serve you for several years without much maintenance. It will be easy to drive on it in both dry and rainy weather.

“Riding along the Russian highway is not very amusing” Prince Peter Vyazemsky. Almost 3 centuries have passed since the construction of the first Russian road, "all-weather and horse-drawn", connecting Moscow and St. Petersburg (1746 under the emperor Elizabeth), but for many settlements in Russia, dirt roads remain "roads of life" to this day. Of the 900,000 km available in the country. roads, more than 150,000 km. are dirt roads. It is not always appropriate to recall the Russian mentality, “thunder thunder and pecking rooster”. "Primers" are available in Germany, famous for its autobahns, in the USA with their famous highways, Switzerland, Finland, Japan and other countries of the world.

Where are primers needed?

The construction of dirt roads is expedient on routes with low congestion, relatively cheap, but for all-weather operation it will require competent and constant “prevention”. They must be watered every summer with calcium chloride (for dedusting) and at least once a month they must be graded. In Finland, such "primers", subject to technology, serve for half a century.

It is technology that is still our “stumbling block”. For uniform spreading of gravel screenings (in Finland, for example), a special installation is used. Special equipment of this class is not produced in our country (let's hope that "for now"), they are brought and scattered by dump trucks, raked with a grader and rammed with a roller. To transport across the border and use Finnish or German equipment, you will have to pay such money that the dirt road will become “golden”.

According to the Russian SNiP, a dirt road will be any road built using only soil or soil with additives (gravel, slag, etc.). It is a road of the 5th (lowest) class and can be either with road “clothes” - coating (also of the lowest class), or without it. They are divided into 3 classes:

1. Improved soil, with a road surface of sand and gravel, crushed stone, etc. The maps are marked in yellow.
2. Country soil (not improved). Just a “rolled” road, which, at best, is sometimes “stroked” by a grader. On the maps they are indicated by a solid line.
3. Field and forest dirt roads. In fact - 2 parallel "paths". On the maps they are indicated by a dotted line.

Useful advice: when driving on field and forest roads, try to move in such a way that the wheels are located on the side of the road and in the middle of such a road. Perhaps the "pioneer" of this route is a car with high ground clearance. Then “grabbing” something into the wheel will be much more harmless than running into an overgrown stump in the middle with a pallet.

Unlike forest, field and country roads, which appear according to the principle: “Where I drove, there is the road”, the construction of dirt roads with “clothing” begins with geological exploration of the area. Elevation differences (places of accumulation of precipitation), and soils of the area, and the possibility of further maintenance are taken into account. Depending on all these factors and the climate of the region, the type of road surface is selected and design estimates are prepared and agreed upon.

The construction of dirt roads consists of several stages:

• work on soil compaction, water drainage, preparation of a "trough";
• work on the construction of a "cushion" of the road foundation;
• laying and compaction and processing of the upper fabric (clothes).

Sandy dirt roads are built in places with the least autoload, almost for single cars. The upper part of the soil is selected, the “trough” is prepared, the soil and walls are compacted, which are covered with sand and tamped with a roller to the required degree. The disadvantages include the fact that, as a rule, does not rise above the landscape and is subject to erosion by storm flows and destruction by heavy equipment.

Useful advice: it should be remembered that the application of road markings on a dirt road depends on the sense of humor of the “road builders” or the “high-ranking” persons passing nearby and is not subject to compliance.

The crushed stone road is being built where the traffic of cars is already much more intense than on the "sand" and the weight of the equipment is more significant. The construction of such a road should include three stages and crushed stone should be used in 2 different fractions (fraction in French - part, share). The bottom layer in the prepared "trough" is a large crushed stone 40x70 in size and the top layer with a fraction of 40x20. If these conditions are met, then the effect of “wedging” is created (the introduction of smaller particles into the medium of large ones), which contributes to the compaction of the road jacket.

From ASG (sand-gravel mixture), road construction is carried out mainly in the area of ​​\u200b\u200bcottage buildings due to the cheapness and speed of construction. The technology is similar to the above: "trough", base and shirt. Minus - instability to the effects of water and temperature, hence fragility.

Useful advice: when driving on dirt roads, you should remember that the load on the undercarriage of your car will pass "painlessly" only if you follow the golden rule: more pit - less speed. Otherwise, recklessness is fraught with wear of rubber-technical parts and failure of suspension elements.

The construction of a layered road of crushed stone and sand is most appropriate in most climatic zones of our country. The sand will create the necessary drainage for water removal, and the crushed stone layer will provide the necessary compaction that even trucks can withstand. As with any paved road, patching is necessary, adding crushed stone of various fractions in places where potholes have formed. The construction technology is similar to those previously listed, while this type of road will adequately withstand frost and show good moisture absorption during precipitation.

Soil strengthening methods

There are many methods by which it is possible to strengthen the soil:

• granulometric additives (crushed stone, sand, loam, gravel, etc.);
• organic binders in you (tar, bitumen, emulsions, resins);
• mineral binders (sodium silicate, lime and cement);
• salt solutions (sodium and calcium chloride, etc.);
• soil treatment with electrochemistry (direct current transmission with the help of electrolytes);
• heat treatment (burning of soil on local fuel);
• complex soil treatment.

Dirt roads with soil stabilization.

Modern construction technologies make it possible to turn simple crumbly soil into a monolithic canvas reinforced with a stabilizer. Roads with soil stabilization were widely built in the West in the 80s, although work in the direction of giving the soil other properties has been carried out since the 20s of the last century in our country. Back in 1926, liming of the soil was carried out in the USSR, but due to instability to frost, it was recommended only for the bases of the roadway. In the United States, country roads were built using cement-soil technologies.

The essence of the modern idea of ​​stabilization is simple: in the normal state, soil molecules are held together by the forces of electrostatic and chemical interaction. The soil is treated with a chemical substance (stabilizer, modifier) ​​that replaces anions (OH) in molecules, the forces of mutual attraction increase. Modern developments of stabilizers by Russian specialists (ANT technology - ant) ​​are limited only by the weight of equipment for road compaction. If it were physically possible to increase the ramming pressure by 5 times, then the strength of the resulting road would correspond in hardness to M200 concrete.

For construction, the soil already available on site is used, which entails significant savings, and the strength of such a dirt road is 3-5 times higher than that of an untreated one.

The top layer of soil to a depth of 20-30 cm is loosened and crushed with a cutter. The amount of sealant and additives (possibly grouting) is determined, which are required per sq.m. roads. A stabilizer is introduced into the soil by re-mixing with a cutter and the soil moisture is brought to the optimum (at which the forces of the electrochemical action of the soil molecules will be maximum) and in this state the soil is compacted with a roller. In case of insufficient moisture, the soil is irrigated with water from irrigation equipment.

Modern stabilizers allow mixing with fresh or salt water. The top layer hardens completely in 1 to 4 weeks, but traffic on it is already possible in just 2 hours after compaction.

The benefit is obvious:

• the properties of "adhesion" of the soil remain for a very long time;
• modification or stabilization suitable for any kind of soil;
• the treated (modified) soil can be stored separately at the construction site, ready for use (before compaction);
• minimal damage to the environment and landscape;
• in case of damage to the road “shirt” of stabilized soil, there will be no broken pieces (as in grouting) that can lead to accidents on the road.

Soil stabilizers chemical, organic and synthetic are constantly being improved. The scope of their application is becoming wider. From strengthening the banks of reservoirs and building stadium tracks to the production of bricks from the ground and the construction of airfield strips.

Conclusion

Whatever the dirt road, for its operation at any time of the year, it needs maintenance. Timely removal of dust and snow drifts, a competent and constantly clean drainage system, all this is necessary for safe movement and durability of any road. Whichever of them you have to travel, remember to comply with traffic rules and safety measures. Neither a rod to you, nor a nail!