Reference book Encyclopedia of the road builder. Volume I. Construction and reconstruction of roads. Road construction

The first stage of any construction (or reconstruction) is, of course, design. Then, geological surveys are carried out, during which the specifics of the working area become clear. Based on these data, a road construction plan is being developed. Also in the process, you can get a lot of related information - for example, to identify natural processes that are dangerous for road construction. Further construction work can be conditionally divided into stages such as:

Topographic survey and breakdown of the construction site

At this stage, an analysis of the terrain along which the road will pass is carried out. It is important to note that the device highways  always implies the need for topographic marking of the territory, including in those cases when it comes to the construction of an additional interchange or parallel road.

Analysis of the construction site is carried out by surveyors using special equipment. In this case, the features of the relief, soil, the presence of depressions, and so on are analyzed.

Site preparation

During the preparatory phase, the territory is cleared, communications are transferred, and any mechanical barriers are removed. In the case when it comes to the construction of additional interchanges, partial or complete blocking of traffic is possible.

Construction of an earthen pavement, the creation of an embankment if necessary

Actually, construction work begins with the creation of an artificial hill. For this, the sand mixture is most often used. At the same time, each subsequent layer of sand is necessarily compacted to create a reliable foundation for the future road.

Alignment of a site, elimination of a relief

A mandatory step in the construction of roads is the elimination of the microrelief of the territory. The surface on which the asphalt will be laid should be perfectly smooth.

Construction of a drainage system and auxiliary structures

The drainage system ensures safe drainage of water from the future pavement. Its installation is carried out in accordance with the features of the terrain, so that moisture flows down a sufficient distance from the road.

Laying "pillows" - depreciation layer

The so-called “pillow” serves to smooth out the mechanical impact on the road surface. It carries out cushioning, as a result of which the coating will last much longer.

Crushed stone

Crushed stone or material with similar properties is the usual basis for a roadbed. It serves as a basalt layer of the road, easily withstanding multi-ton mechanical stress.

Laying Finish

Modern technologies allow to pave the pavement quickly enough, and at the same time ensure the highest quality of the finished road. Roads built using these technologies are characterized by durability and reliability.

Marking

The last stage is preparing the road to the opening of the movement. It includes not only the marking of the canvas, but also the installation of additional structures, the installation of road signs and so on.

One of the most important elements of road construction is asphalting, when on a prepared foundation subgrade  (stone or reinforced concrete "skeleton") the asphalt mix is \u200b\u200bdistributed (in one or several layers), then it is "trampled down" - and the road is ready. The longevity of a particular road depends on how high-quality this mixture will be and how professionally the work will be carried out. After all, the top layer of the road surface is not accidentally called the “wear layer” - every day a huge mass of passing cars presses on it. So, you need to make this coating strong and durable. Asphalt laying can be made of various materials: asphalt concrete, cast asphalt, crushed stone, crushed stone with bituminous impregnation, gravel or impregnated soil, etc. Often, when building roads, bitumen or the so-called secondary building materials are used: asphalt crumb, broken brick and asphalt chip. The most common type of construction is the laying of asphalt concrete. Asphalt concrete is crushed stone, sand, stone flour and actually melted asphalt mixed together. This "filling" is laid out on an earthen base in several layers. By the way, due to layering roadbed it is often called the "road cake". The number of layers depends on various factors, but above all, on the estimated transport load. It is noteworthy that crushed stone is put into the lower layers larger, so that the road is strong, stable, durable. And in the upper layers fine gravel is poured - this gives the road surface qualities such as high wear resistance and water resistance. In addition, due to the presence of small gravel, the surface of the road turns out to be a little rough, and this is necessary so that the tires of cars do not slip.

Asphalt is laid, as a rule, using special equipment. You can do this manually, if construction volumes allow. However, most often without pavers during construction can not do. Well, the famous skating rink, compacting asphalt, makes the road surface smooth, holistic and strong. By the way, there is a kind of skating rink - vibroskating rink. Its special technology makes the roller itself constantly vibrate, which gives an additional “tamping”, and the asphalt becomes more dense and durable. Another type of asphalt laying is the technology of working with the so-called cast asphalt. This is the same mixture, but cooked at very high melting points. The viscous-fluid mixture is brought to the construction site in special containers that keep the temperature, and hot is poured into the place of the future road. The molded asphalt is plastic, it is easy to pave, and additional compaction is not required. A road made of such asphalt can withstand heavy traffic loads and is well resistant to wear and corrosion from studded tires and anti-icing agents. In addition, cast asphalt absorbs noise well. With the advent of new technologies, road construction is constantly being improved. The use of more modern equipment and high-quality materials can not only reduce the cost of construction, but also guarantee the reliability and durability of the future road. For example, the composition of the asphalt concrete pavement is improved, making the roads safer and more durable. So, components that improve the coupling properties with car wheels can be included in the mixture - on such roads, drivers are not afraid of rain or light icing. Or special modifiers are added to bitumen - and in this case, asphalt concrete will experience less cracking during sharp jumps in temperature. A modified bitumen in combination with granite fillers and special additives, it will protect the coating from the “vagaries of nature" when the roads freeze, thaw, or freeze again, which deteriorates their quality.

Types of Roads

The device of the roadway

Construction stages

Travel clothing

Road construction includes design, construction, as well as repair and maintenance of roads, access roads, streets. Road construction works are carried out using special technologies and involving equipment, road equipment.

Types of Roads

An automobile road is a long, high-quality road with high throughput. Among the roads, depending on traffic conditions, they distinguish:

1. Motorways  with divided lanes, interchanges, providing direct transport links between settlements.
2. Express roads  with controlled access and divided lanes, as well as junctions.
3. Ordinary roads  - they may not have a dividing strip.

The device of the roadway

The road is a complex engineering structure. In the organization of the roadway, the following structural elements are distinguished:

1. Carriageway  - The main element of the road along which vehicles move.
2. Dividing strip  - limits movement in each direction.
3. Roadside  - supports the web, also designed to stop cars, pedestrians.
4. Ditch  - is a fortified trench and is designed to drain water.

The strength of the roadway must correspond to the stresses it experiences. In addition, it is necessary to ensure convenient and safe movement of vehicles.

The device of the road takes into account the terrain. Earthworks, carried out at the very beginning, provide a stable position of the bulk of the road - pavement. Open and open drainage structures in the form of ditches, trenches are used to drain water.

Construction stages

Road construction can be divided into stages:

1. The preparatory phase.
2. The construction of the subgrade. At this stage, the fertile layer is removed from the ground and the road base is prepared, arranging the embankment, compacting the soil and strengthening the slopes.
3. The introduction of special layers in the subgrade. These measures are based on the features of the relief and soil, improve frost resistance, drainage properties and other parameters of the embankment.
4. The construction of pavement: pavement, base and intermediate layers.
5. Asphalting.

Travel clothing

Road clothing consists of several layers and is designed to take on the load of moving vehicles. Types of pavement are combined based on combinations of road building materials, taking into account the requirements normative documents.

Travel clothing consists of:
- lower part - base layers and
- top - coating layers.

The upper layers of the coating have the main load.  For this reason, they are prone to destruction - such as:
- cracks
- breaks and potholes,
- rut
- wave-like deformations.

At the base of the pavement, the voltage is suppressed. If necessary, build additional layers using sand, soil, binders and various additives. They can increase the frost-resistant and water-removing characteristics of the road, giving it special strength.

1. Basic concepts, terminology, classification

Highway   - a complex of structures designed for convenient, safe and year-round traffic of vehicles with estimated speeds and loads.

Structurally, an automobile road (highway) is characterized by transverse and longitudinal profiles (Fig. 17.1.).

Figure 17.1. Road profiles: A) Cross section;

B) a longitudinal profile; 1 - dividing strip, 2 - pavement, 3 - reinforcing strip, 4 - curb, 5 - base for pavement,

6 - body of the embankment, 7 - slopes (transverse and longitudinal), 8 - cuvette, 9 - zone of concentrated work, 10 - natural profile of the terrain.

Let's get acquainted with the terminology that characterizes the main structural elements of roads:

• transverse  profile - the cross section of the road, characterizing the constituent structural elements;
• longitudinal  profile - a longitudinal section of the road characterizing the constituent structural elements;
• carriageway  - the main, operational part of the road along which the movement of vehicles;
• subgrade  - volume earthworks  on the device of the bulk of the road;
• right of way  (alienation) - the area of \u200b\u200bthe construction work in the cross section of the road. This zone is allotted during the design for the entire construction complex (including the organization of construction and the prospect of expansion of the road);
• dividing strip  - A constructive zone of the road dividing opposite directions of movement. It is not intended for use and usually has a decorative look;
• pavement - The main, artificially fortified part of the carriageway, intended for operation;
• fortification strip  - part of the pavement located between the pavement and the curb. Serves to protect the edges of the coating in the area of \u200b\u200bincreased loads;
• road surface  - part of the pavement, the most durable in a structural respect, designed for traffic;
• roadside  - part of the pavement located along the borders of the transverse profile. The roadside has an important operational value (stopping and parking vehicles, movement of pedestrians, the location of construction equipment during repairs, etc .;
• ditch  - a drainage trench with a calculated longitudinal slope, reinforced bottom and slopes;
• embankment body  - the total amount of earthwork (embankment) performed during the construction of the road;
• area of \u200b\u200bconcentrated work  - the front of labor-intensive work, concentrated on a limited area of \u200b\u200bthe relief.

Roads are classified by purpose and pavement design.

By destination, roads are divided into:

• the roads   general purpose.  The classifier contains six categories of roads, characterized by the following parameters: traffic intensity; the width of the carriageway; number of lanes; the presence of curbs, dividing and reinforcing strips;
• urbanroads are classified by the minimum number and width of lanes, the estimated speed, the presence of the sidewalk. High-speed, trunk, local (district and city) and intra-quarter types of roads are distinguished;
• rural  the roads. They are divided into three categories depending on the width of the carriageway (3.5 ... 6.0 m) and the presence of curbs.
• According to the design of the pavement, the roads are divided into:
• roads with improved coating (capital and lightweight). These are asphalt concrete, cement-concrete and block-pavement coatings;
• transitional coatings: prefabricated reinforced concrete slabs, crushed stone, soil crushed stone and slag coatings;
• lower: dirt roads, fortified with gravel, gravel, rubble.

2. Organization of road construction.

The construction sequence is established on the basis of the division of all road construction works into three periods: preparatory, main and final.

In preparatory  the period, the organizational and technical preparation of the construction is carried out to ensure its deployment in the initial sections determined by the construction organization project.

IN main  period carry out all construction work.

IN finalperiod liquidate the base and other temporary structures, carry out land restoration.

All types of road construction works are divided into:

• procurement - includes the preparation and storage of materials, semi-finished products and parts manufactured by construction industry enterprises (stone preparation, preparation of asphalt concrete, construction of bridge structures, pipes, road conditions);
• transport - road materials are transported by automobile, rail or water transport. This group of works includes the delivery of materials and semi-finished products to warehouses, factories, intermediate bases and to places of direct laying;
• construction and installation works - work is underway on the erection of all the elements of the transverse profile of roads, the arrangement of road conditions, the construction of buildings and structures of road infrastructure.

By uniformity and repeatability, road construction works are divided into linear and concentrated.

Linear- work, the volumes of which are evenly distributed throughout the object. These include: excavation, the installation of bases and coatings, the device of culverts, small retaining walls, etc.

Focused- work of high labor intensity, concentrated on a small extent (bridges, large excavations and embankments, road junctions at several levels, high throughput culverts).

For the organization of linear work, two methods are used: in-line and separate organization. Flow  the method performs road construction work on all linear objects with a sufficient length. The complex flow method provides for continuous and uniform production throughout the entire construction period. If the length of the road section is insufficient and the periods of deployment and curtailment of the stream exceed the time of its effective operation, then the work is carried out by the method separateorganizations in which each construction process is carried out independently.

Similarly, concentrated site work is performed.

When organizing construction in general, it is widespread and uncomplex inline  the method when the subgrade, small and medium bridges and pipes are erected a year before the construction of pavement by the in-line method, and pavement is built separately (in-line method, not connected by a single schedule of all works).

With a new road construction, as well as during reconstruction over a sufficient length, the in-line method provides for: the implementation of all construction work by complex mechanized units (columns, detachments, brigades); providing them with the necessary resources, including those produced by mobile roadside installations; the movement of specialized units continuously one after another along the road of the road under construction with an established average flow rate, leaving behind a completely ready road.

The main spatial parameters of the flow are: grips, plots, maps, assembly sites (depending on the type of work).

The flow rate calculated as the length of the finished road ending in a shift (the main flow rate) is taken as the main time parameter. The flow rate is set during the technological design.

In the process of technological design, the most modern technologies  production of road construction works based on integrated mechanization. In each specialized stream, a leading machine is provided, with which the capacities of auxiliary machines and mechanisms are linked. The efficiency of choosing a set of machines is estimated by the cost of the unit of work (1km, 1m 3, 1t, etc.).

Features of road construction must be taken into account when drawing up calendar schedules and construction plans. They must be “attached” to the topography of the area, take into account the mobile nature of the work, the supply of a large number of building materials, structures and products. Stroygenplany should be drawn up for various periods of construction and for all areas with specific working conditions.

3. Preparatory work

Preparatory work in road construction is carried out almost constantly. As one section of the road is completed, it is necessary to prepare the front of work for the next.

The composition of the preparatory work is established in the "Project of the production work." An approximate list of technological complexes:

• creation of a geodetic base and a breakdown of the route;
• rOW clearing
• drainage and temporary water reduction;
• removal of engineering networks and demolition of buildings and structures falling into the right of way;
• the device of temporary roads and detours;
• device quarries and reserves.

Preparatory work can only begin after the approval of the ROW and the conclusion of contracts for land temporarily used for construction needs ( restitution).  After the construction is completed, the restitution is returned to the land user with mandatory reclamation.

The geodetic alignment base is created in the form of a system of polygonometric (theodolite) moves along the highway route. The base coordinates and marks of the alignment points must be obtained from at least two benchmarks of the existing geodetic network. It is necessary to take measures to ensure the safety and stability of geodetic signs.

A track is a set of lines that determine the position of the road in the plan (longitudinal axis, edges and soles of slopes). Breakdown of the route (restoration and consolidation) is carried out as follows:

• elevations along the axis of the road are restored no less than 100 m in a straight line and 20 m in curved sections. Fastening is carried out by firmly clogged poles and high milestones or pegs (gatehouses) with their removal outside the work area of \u200b\u200bearthmoving equipment and indicating the distance of the leader. Picket - by firmly driven stakes with their removal outside the work strip.
• the border of the sole of the embankment is fixed with pegs after 20 ... 50 m or a furrow;
• the turning angles of the route - firmly dug in corner pillars (with a diameter of at least 10 cm and a height of 0.5 ... 0.75 m). The columns are located on the continuation of the bisector of an angle of 0.5 m from its top. Plates with angle parameters are fixed on the posts;
• The right of way is secured by pillars on each side of the axis of the road.

Technologies for preparatory work do not fundamentally differ from those adopted in civil engineering.

4. Construction of the subgrade

The subgrade is the main structural element of the road and its construction (organization and production technology) is crucial in road construction.

When constructing the subgrade, the following technological complexes of construction work are performed:

• detailed breakdown of road elements and preparation of the foundation;
• excavation and embankment construction;
• soil compaction;
• final planning, strengthening slopes.

A detailed breakdown of the subgrade and structural elements is carried out depending on the method of production of mechanized work and set in the appropriate technological cardsoh. The main alignment marks are placed on the edges, and the correctness of the subgrade shape during the work is controlled by level, sighting glasses and additional measurements. All marks are placed on the center stakes. During the operation of road machines, it is necessary to ensure that the marks remain until the end of work on the site.

Preparation of the base for the subgrade includes: removing the fertile layer; arrangement of measures for surface drainage (creation of working slopes, drains, drainage ditches); fixing and replacing soft soils. These works are mainly carried out in the preparatory period.

The development of excavations and the construction of embankments - the main scope of work in the construction of the subgrade. Depending on the terrain, transverse profiles can have a different look (Fig. 17.4.).

The construction of the embankment

The construction of the embankment consists in the sequential laying of previously developed soil with compaction. The suitability of the soil for the construction of the subgrade is determined by their road-building properties. Coarse, sandy and sandy loamy soils are most suitable. Clay soils are unsuitable, or unsuitable due to the tendency to frost heaving and technological difficulties when filling and compaction.

Soils are poured in layers with a thickness of 0.5 ... 1.0 m, depending on the type of soil and the accepted (in the technological map) production technology. immediately after filling, the soil is leveled and compacted by soil compaction machines. The advantages of this method can be considered the ability to get rash with different characteristics of density and the construction of the embankment from various soils.

For the construction of the subgrade use bulldozers, scrapers, graders, excavators. The choice of driving machine depends on the height of the embankment, the type of soil and the range of its movement.

When organizing an object stream, the front of work is divided into paired captures. At the first grab, soil filling is carried out, and at the second - compaction. The dimensions of the grips are related to the performance of soil compaction machines and soil moisture.

When constructing the embankment, it is necessary to take into account the change in the volume of dumping as a result of artificial compaction (against the volume of soil in the reserve).

V n \u003d V p / K y

Where, K y - the coefficient of relative compaction of the soil in the embankment compared with its natural density in reserve;

V n - the volume of soil in the embankment;

V p - the volume of soil in reserve

When filling the upper layer, the width of the edge increases by 0.5 m in order to place a reserve of soil for subsequent lay-outs while maintaining the embankment (for self-compaction).

When drawing up technological maps, it is necessary to establish schemes for the development, movement and laying of soil with an indication of the elevations of the embankment for each layer, the working and idle strokes of the main machines, the design and working geometric parameters of the subgrade.

When performing work in concentrated areas (for example, filling the soil in a wetland area), the work can be organized: by the “pioneer” method - filling sand in flooded soils to squeeze water, and then layer by layer the subsequent fillings.

Excavation Design

The development of excavations in road construction is carried out according to two main schemes: half-mound-half-excavation and a full profile.

Shallow excavations are developed by an excavator using the “frontal driving” method right up to design marks.

Deep excavations are developed in a tiered way. Development is carried out in the transverse and longitudinal directions. In a cross-section, the recess is divided into tiers with a face height corresponding to the design parameters of earth-moving machinery (determined in the technological map). Each tier must have a berm for the passage of working vehicles and ensure the stability of the slope.

Full profile dredges, depending on the type of soil, are developed by single-bucket or multi-bucket excavators with soil dumping by dump trucks to the reserve or to the road embankment in other sections. For the development of sandy soils, various grapple buckets can be used.

The subgrade in a half-half-half-excavation is usually carried out with bulldozers. For large volumes of work, scrapers can be used. Alignment of the bottom of the excavation is carried out by graders, and slopes - planners, slopes.

During work half-excavation-half-mound, in order to avoid deformation of the subgrade, due to uneven sediment, a sharp (steepness) boundary between the embankment and the notch is not allowed.

When developing soil, it is always necessary to provide drainage structures on slopes and slopes on each tier of the excavation. Before starting the main work along the longitudinal axis of the excavation, a pedestrian path and a working passage are laid to ensure the passage of personnel and the passage of the machines and mechanisms involved in the work.

In the presence of strong soils, special technological documents (PPR, TK) for blasting are developed. In winter, layer-by-layer loosening of frozen soils is carried out.

Compaction of sprinkled soils.

Soil compaction in artificially sprinkled embankments has the following objectives:

• contributes to the improvement of soil structure and its uniformity;
• increases the stability of the subgrade;
• reduces uneven precipitation during moistening, freezing and thawing of soil filling;
• provides the maximum possible modulus of elasticity of the upper soil layers, which allows to reduce the required thickness of expensive clothing.

Creating a stable earthen is mandatory in all cases when pavement is arranged immediately after the construction of the embankment and in the recesses within 1.2.5 m. The value of the necessary density is set in the project (within 0.85 ... 0.98 of the density in the natural occurrence).

Numerous experiments show that in order to obtain the most dense structure, it is necessary that the soil moisture is such that the percentage of trapped air is in the range of 4-6%. In this case, the most durable hydration shells are formed, which provide the minimum filtration and the smallest swelling of the soil, and, consequently, the highest possible modulus of elasticity. If the humidity is lower, i.e. the pore volume occupied by air is higher, then a stable structure is not created and when moistened, the soil swells easily, and the more, the lower the humidity, and when the density is insufficient, on the contrary, it thickens and gives a precipitate, and the elastic modulus decreases in both cases. If humidity displaces the indicated percentage of air, then the structure also becomes unstable, especially during shock compaction, and the elastic modulus decreases.

Soil compaction is carried out in layers (layer thickness 0.3-0.5 m), followed by their filling. The work is being carried out by a link of soil compaction machines for grips. The capture size (L) is set in the PPR within 100 ... 300m.

L \u003d P t o / 2T h B

Where: P - productivity of the link of compacting machines m 3 / hour .;

t o - time to maintain optimal humidity, sec .;

T - the duration of the shift, hour .;

h, B is the size of the rolling layer.

The optimum soil moisture during rolling depends on the type of soil and is in the range: clay-23 ... 28%, loam-15 ... 25%, sand - 8 ... 14%. If the soil dries, then watering with watering machines is carried out. Water is bottled in several stages, alternating hydration with mixing by plowing or loosening. Waterlogged soils are dried (arrange technological breaks in work).

Soil compaction is carried out over the entire width of the embankment with the provision of overlapping the track of the previous penetration by 20-30 cm. The number of penetrations is calculated in technological maps - (from 3 to 12).

The choice of compaction method depends on the type of soil and its moisture.

• Rolling  - it is applied to almost all types of soil. Various types of rollers are used: pneumatic wheels and smooth self-propelled - for all soils; cam - for liaisons; trellised - incoherent clastic, lumpy, frozen. Rollers can be self-propelled and trailed weighing from 3 to 25 tons.
• Vibrating  - it is applied at disconnected and poorly connected soils (sand). Trailed and self-propelled vibration rollers with a weight of 3-12t are used, vibration damping plates weighing 125-750kg, vibro rammers.
• Ramming  - it is used for all types of soils, laid in cramped conditions, in winter, with large-thickness dumps (up to 1.5 m), rafts on slopes, etc. We use ramming plates suspended from the boom of an excavator weighing 2-12 tons; diesel rammers based on the T-130 tractor; light (0.1-1.5t) pneumatic and electric rammers. When calculating the efficiency of tamping, they are set by the height of the plate fall and the number of strokes is calculated.

After compaction, laboratory quality control of the work is performed.

Subgrade finishing and slope reinforcement.

In the process of the main excavation work, the embankments and excavations get a rough outline - their slopes are uneven, the edges are twisty, and the unfinished soil remains in the excavations. To give the transverse profile of the design form, special finishing and strengthening works are performed.

Finishing includes the layout of the surfaces of embankments, excavations and reserves. To reinforcing ones - strengthening of slopes of embankments, excavations and reserves; the bottom of reserves and ditches from erosion by water and blowing by the wind. Planning of the subgrade and cleaning of the recesses to design marks is carried out immediately after the completion of the main work by a specialized link.

Planning order: embankment  - subgrade, slopes;

notches  - slopes, bottom of the recesses.

Planning work is carried out by motor graders, excavators and bulldozers with attachments (slopes, dump expanders, scrapers, plows). To refine the excavations and reserves, earthmoving machines are used - bulldozers, scrapers and dragline excavators.

It is desirable to carry out finishing work at optimum soil moisture, which allows the use of cut soil to backfill lowerings, its good compaction and facilitates the operation of machines.

Planning is carried out, starting from the lowest sections (in a longitudinal profile), to ensure drainage during the production process. Graders can plan slopes of more than 1: 3 with direct movement along them. Steeper slopes are planned using a knife extension and by moving the grader knife to the side. Graders are planning slopes of embankments up to 3.5 m.

Planning is carried out in several penetration passes. The estimated length of the capture is 300 ... 1000m, depending on the soil and the type of planner. For large volumes of work, it is advisable to use automatic dump control systems (“Profile” -P, “Profile” -30, etc.). The operation of these systems is based on the functioning of electric drives from sensors attached to a blade and moving along a taut carbon string or receiving signals from laser sensors.

The layout is rough and final. Rough - before holding the embankment; final - before the coating device.

After planning or completion of the construction of artificial structures, earth slopes  (strengthening work). It provides stability and reliability of the entire subgrade. To be strengthened: slopes and roadsides of the subgrade, cones and approaches to small artificial structures, the upper part of the subgrade.

Mount Designs:

• vegetative grass cover - is performed by sowing long-term grasses or by laying a previously removed soil and plant layer;
• planting trees and shrubs;
• the sodding of slopes by laying and temporarily fixed with needles of plaz-squares of pre-prepared turf;
• installation of prefabricated reinforced concrete elements in the form of continuous or lattice block-plates;
• fastening slopes with a stone outline of sorted stone, arranging stone banquets at the foot of the slopes;
• monolithic fastenings of slopes made of concrete with reinforcement;
• fastening by fascines, gabions, reinforced soil.

The type of fastening depends on the steepness of the slope, the material of the slope, weather conditions, the availability of local materials, the possibilities of mechanization, etc.

The device of special layers in the subgrade.

Additional layers and layers reduce moisture at various points of the subgrade, which prevents the embankment from freezing and subsequent uneven sediment after thawing. Measures to reduce soil moisture must be applied when using heaving soils. Additional layers and layers help reduce the thickness of expensive layers of pavement.

Additional layers are divided by purpose:

• frost protection (heat insulating) - are used to increase the temperature of the embankment in the ice formation zone. They are made of concrete mixtures with lightweight aggregate; porous stone materials treated with binders; ash and slag mixtures. The laying of various synthetic materials gives a high effect. Their laying is made according to individual technological schemes.
• Draining  - increase the filtering coefficient of the embankment in hazardous areas (according to freezing conditions). They are arranged by filling and compaction of coarse-grained sand, gravel of various fractions, sorted stone.
• Waterproof  - are arranged on slopes and under pavement, serve to cut off atmospheric waters. They are made of hydroisol, a synthetic film. Impregnation of local soil with an organic binder is often used (tar, liquid bitumen, oil emulsions). After impregnation, loosening is carried out, followed by rolling.
• Capillary interrupts (anti-silica) - create a pre-degree for raising capillary water. They are used at high groundwater levels. The basis of the design is a layer of draining material on which capillary rise of water is impossible. Performed in the form of a "reverse filter" of sand and gravel of various fractions.

With a close occurrence of the aquifer, a sub-drainage and sloping drainage is arranged with a drainage drainage below the estimated freezing depth.

The device of additional layers and interlayers is carried out in the process of filling the embankment. After completing the interlayers, further rafts are carried out according to the “on their own” method using bulldozers, since it is forbidden to enter the interlayer of vehicles and earth moving vehicles until a compacted layer of soil with a thickness of at least 0.5 ... 0.6 m is created.

5. Pavement device

Modern pavements consist of several structural layers: coating - the top layer of pavement, which may consist of a wear layer and one or more bearing layers; base, which may consist of upper and lower bearing layers; additional layers for various purposes.

Natural soil base has a significant impact on the work of pavement in general and on the work of its individual layers in the process of construction of the road. Therefore, it is advisable to improve the soil base in various ways in order to increase its bearing capacity and ensure the possibility of movement of working vehicles during the construction period.

The base device under the "upper" coating layer

The range of works on the device base under the "upper" coating layer includes the following technological complexes:

• additional profiling and adding the upper layer of the body of the embankment;
• arrangement of temporary access roads, storage areas for materials, access ramps;
• improvement and compaction of the soil base;
• the device of additional layers and interlayers;
• construction of dividing strips;
• preparation of the “black” foundation.

During the construction of high category roads, a technological break is provided for self-sealing of the embankment. After filling the top layer of the soil base, the construction of the road is suspended and traffic is allowed with restrictions on speed and intensity of traffic for a period of one year. During this period, the embankment gives a settlement draft and self-compacts. In this case, the marks of the top of the embankment change in the direction of decrease. After the resumption of construction, a geodetic survey of the profile is carried out and the missing soil is poured with compaction to design marks.

At the same time, work is underway to ensure technological requirements for the construction of the main coating provided for by the construction plan.

These include temporary technological platforms, access roads and exit ramps to the place where certain processes are carried out by specialized flows. The device of temporary entrances is associated with the movement of a large amount of soil and the presence of a fleet of permanent machines for excavation.

With additional profiling, soil quality studies are carried out and, if necessary, the top layer of the soil base can be removed and replaced, or loosened and compacted, with the addition of additives that improve the quality of the foundation. In the same period, some additional layers are arranged (anti-silica, heat-shielding).

If the project provides for a dividing strip with planting of trees and shrubs, then its construction should be ahead of the construction of bases for the coating and the coating itself. In the absence of landings, the installation of the border of the dividing strip can be made after the first placer gravel base.

Crushed stone base is the main (bearing) layer of pavement on which the coating is laid. Its purpose is the perception of the load from automobile transport through the coating and its distribution on the subgrade. Crushed stone is poured in layers, in accordance with the project, and compacted. As a material, sorted gravel of various fractions is used, which has a wear grade of at least I - ΙΙΙ. For transitional coatings can be used various crushed stone  and gravel.

The work on the installation of crushed stone foundation is one of the most labor-intensive and is carried out in two stages.

Ι stage - distribution of the main fraction of the layer and its preliminary compaction (with compression and interlocking);

ΙΙ stage - distribution of proppant crushed stone with compaction of each fraction (rivetting).

The technological cycle includes the following processes:

• the first placer of large gravel of the calculated fraction with a layer of 15-25cm;
• leveling by a grader or bulldozer;
• compaction by rollers in several passes;
• scattering of a layer 10-15 cm thick of a finer fraction;
• grader leveling;
• compaction with watering rollers (water consumption 15 ... 25l / m 3);
• placer splitting  fractions, watering and compaction with a flow rate of 10 ... 12 l / m 3;

The sizes of the fractions relate to each other as 1: 0.5: 0.3. Tentatively, you can take:

1 layer - 80 ... 120mm, 2 layer - 40..60mm, 3 layer - 10 ... 20 mm.

When compaction, rollers with smooth rollers or vibro-rollers with a mass of 6 ... 18 t are used (depending on technological requirements). In the PPR, the size of the grab (card), the order of alluvial placers, the number of penetrations during compaction, the mass of rollers for each rolling layer, and watering technology are established.

During the construction of high-speed highways, an additional one or two layers of the “black base” are arranged, designed to equalize operational loads. Structurally, these layers are made of high strength mineral material treated with a binder.

The black base is arranged in one of the following ways:

• the mixture is prepared at the ABZ (asphalt concrete plant) in mixing plants and delivered to the place of laying by specialized vehicles. Hot mix  with a temperature of 100 ... 110 о С it is laid by pavers and compacted by a link of rollers with smooth rollers;
• crushed stone delivered to the place of laying is mixed at the on-site technological site with a binder and stacked in piles. As needed, the material is consumed in the embankment. Before laying, the mixtures are heated and stacked warm (80..90 о С) or cold (60..70 о С);
• the crushed stone base is laid in an embankment, impregnated with a binder (liquid bitumen, coal tar, emulsions of various compositions) and compacted in a few penetrations.

The choice of this or that method depends on the adopted technology for the construction of the road, the range of delivery of mixtures from the automatic storage plant, outdoor temperature, and other reasons. You should know that the higher the temperature of the mixture during installation, the faster it hardens. However, hot mixtures after hardening are more fragile and less durable.

Hot mixtures are used in new construction, when high-speed paving is required. Cold mixtures are preferable for repair work.

After laying the “black base”, a waterproof film made of bitumen emulsion or “ethinol” varnish is arranged on it.

Asphalt technology

Asphalt concrete pavements are most suitable for the perception of loads from automobile transport, they are relatively cheap and simple in the performance of road construction works - therefore, they are universally used for the main coating.

Asphalt mix (ABS) consists of the following components:

• crushed stone- sorted, from igneous, sedimentary or metamorphic rocks with a wear grade I-Ι ... I-ΙV and a strength grade of 1400 ... 500 kg / cm 2 are used;
• sand- natural or crushed. Usually large and medium sands are used, clean, containing no more than 3 ... 5% of dusty, clay and silty particles;
• mineral supplements  - aggregates designed to increase the strength and corrosion resistance of ABS, improve the adhesion of crushed stone with a binder and binder consumption. They are enveloped with bitumen in the contact zone, forming water-insoluble compounds that affect strength, water and heat resistance. asphalt mixes. Additives are powder, a product of fine grinding of limestone, dolomite, metallurgical slag and other industrial wastes;
• astringent  - organic macromolecular compounds. They adhere well to the surface of mineral materials, have plasticity, elasticity, resistance to weathering, and are insoluble in water. The main binders include oil bitumen  and emulsions and tar made on their basis.

Oil road bitumen  subdivided into viscous and liquid.

Viscous bitumen  classified according to the main indicators: viscosity, extensibility and softening temperature. The mark is assigned according to the penetration indicator (the depth of penetration of a standard needle into bitumen at a temperature of 25 and 0 ° C per

5 sec. under the action of cargo 100g). The range of grades is BND200 / 300 ... BND-60/90.

In the case of using high viscosity bitumen, the strength and stiffness of the coatings increase, less viscous bitumen increases the resistance of asphalt at low temperatures, but increases the hardening time.

Liquid bitumen  obtained mainly by mixing viscous bitumen (grades BND40 / 60 or BND60 / 90) with a thinner. Liquid bitumens well envelop mineral materials, creating a thin, strong and waterproof film on their surface. The main indicator of liquid bitumen is the viscosity determined by a standard viscometer. Stamps are set according to the flow rate of 50 ml of bitumen at a temperature of 60 ° C through a 5 mm hole in the bottom of the viscometer. Range of grades: SG40 / 70 ... ... MGO130 / 200.

The composition of the asphalt mixture includes by weight: 40 ... 65% of rubble; 30 ... 50% of sand; 10 ... 15% of mineral additives and 2 ... 10% of binders. In technological design, the composition of the mixture is calculated.

Asphalt mixtures are hot, warm and cold.

Hot  - are made using viscous bitumen, the working temperature is 170 ... 90 ° C. The technological (working) state, depending on the outside temperature), about 1 hour. The range of transportation from 20km (in winter) to 50km (in summer). Traffic can be opened after 3..5 hours after installation and compaction.

Warm  - are made using low-viscosity and liquid bitumen, working temperature is 140 ... 80 ° C. Stacking is carried out only at positive air temperatures. These mixtures have increased crack resistance at low temperatures. Hardening after laying lasts at least one day.

Cold- are made using liquid bitumen or emulsions. Operating temperature 30 ... 50 ° C. These mixtures can be stored for up to 8 months in consumable warehouses and used as needed. Cold mixtures are frost-resistant, can be stacked at negative temperatures (up to - 50 ° C). It takes several days to harden.

Machines used in the construction of coatings.

The following types of machines are used in the construction of asphalt pavements: bulldozers, graders, stone materials distributors (gravel and crushed stone), water-cleaning, sweeping machines, asphalt spreaders, asphalt pavers, road rollers, asphalt boilers, asphalt concrete heating machines, asphalt concrete heating machines beaten dump trucks, heat mixers and thermofilters. The range of mechanisms is very wide. In modern conditions, the rational selection of mechanization will affect the cost of the road.

The technology of laying asphalt mixes

The following technological processes are included in the composition of the main asphalt concrete paving device:

• cleaning the base from dust and dirt with sweepers, if necessary drying and fine bedding;
• checking the geometric parameters of the base (width, elevations, slopes). Measurements are made by theodolites, levels and tape measures. Particular attention is paid to the presence of irregularities when using machines with an automatic servo system to drive the working bodies (irregularities should not exceed 2 mm). If the irregularities exceed the permissible values, then in advance arrange a leveling layer on uneven places from the same material as the base, or from asphalt-concrete mixture;
• detailed breakdown of the edges of the coating, layers, working marks along the axis of the road,
• installation of a base for an asphalt paver tracking system (carbon string or laser system). When using asphalt pads without a tracking system, to comply with the required profile and marks, immediately before laying, control beacons are made of asphalt concrete mixture, the thickness of which should be equal to the thickness of the laid layer in a loose state;
• device bitumen emulsion primer. For strong adhesion of the asphalt layer to the base, the bitumen emulsion is poured with an asphalt emitter a day before laying (emulsion flow rate 0.6..0.9 l / m 2);
• asphalt mix laying. ABS is laid on a solid, clean and dry base at an outdoor temperature of at least 5 ° C (for hot and warm mixtures). At low temperatures, special styling technologies are being developed;
• aBZ seal.

Material (asphalt mix) is fed continuously by dump trucks until the work on the grapple is completed. With a small amount of work, the ABS is poured onto the base manually, smoothed and rolled. This technology is unproductive and requires a large number of workers. Modern construction involves the use of high-performance pavers.

The front of the work is divided into captures and lanes. The length of the fleece is 100 ... 300m. The width of the paving strip is assigned to a multiple of the width of the coating, taking into account the size of the extensions of the paver (3-3.75m). The mixture is stacked in separate short strips 25 ... 100m in turn, but on each half of the coating width. The ABS laying is carried out according to the scheme (Fig. 17.8.).

Having laid one strip, they pass to the next, until the edge of the previously laid layer has cooled down. With this technology, particular attention is paid to the fact that the laid strips of the coating are conjugate, and the resulting longitudinal seams are sealed. In the interface, it is necessary during the compaction process to achieve complete uniformity of the coating texture. The position of the edge of the compacting means is ensured by the correct installation of the paver before the asphalting of each strip.

Pavers can lay the mixture in a layer 3 ... 20cm thick. the thickness of the coating is changed by adjusting the height of the tamper and the screed relative to the frame of the paver. In this case, the compaction coefficient of the mixture is taken into account.

Structural layers of ABS stack integrated teams of 8 people. (including machine operators).

ABS seal is the main technological operation that predetermines the physicomechanical properties of the coating. In the process of compaction during successive passes of the roller, the mixture is deformed due to a decrease in porosity, i.e. reduce the volume of the compacted layer. In this case, the formation of the coating structure occurs.

The sealability of an ABS is influenced by the temperature of the mixture, its granulometric composition and the accepted methods and technologies of compaction. Compaction is carried out by rolling with smooth rollers, tamping or vibration. Compaction of mixtures is usually performed by a link of sealing machines for various purposes. Their selection, the number of penetrations, the temperature regime of the mixture, the geometric parameters of the grips are set by technological maps as part of the PPR.

To ensure the quality of the road surface, it is necessary to organize all types of control (input, operational and acceptance)

At the stage of input control, the compliance of the components of asphalt mixtures with the technical conditions is checked.

At the installation site (operational control), the temperature and quantity of the mixture to be placed are constantly checked, evenness, layer thickness, density, strength, uniformity of asphalt pavements.

Acceptance control is carried out according to the construction phases. All geometric parameters of the longitudinal and transverse profiles are measured, executive schemes, acceptance reports of hidden works are drawn up and submitted to the working commission for acceptance.

ROAD CONSTRUCTION
  The construction industry is involved in the design, construction, repair and maintenance of highways, access roads and city streets. This concept, as a rule, includes management, organization of work and supervision of the condition of roads, equipment and technical meansnecessary for road construction works. Highway means a high-quality road of great length and high throughput. Streets and driveways are roads of local importanceproviding access to highways.
Car roads. The road for direct transport on a continuous route is called the motorway. The ring road leads transport around the urban area. A bypass road allows vehicles to completely or partially bypass a city or industrial zone. Expressways, or freeways, have separate one-way carriageways. At major intersections, traffic interchanges at different levels are provided for them. Access to the expressway is partially or fully controlled. A park road is a highway for non-commercial vehicles (usually in a park or narrow green area) with full or partial access control. Radial highway serves the city center. On a through motorway, transit transport has a preferential right of way, even at the entry point. For the passage of vehicles on toll roads, bridges and tunnels, a set fee will be charged. In the United States, major highways are connected to the federal highway system. It consists of freeways without interchanges at the same level, with partial or full access control, and connects all the country's largest urban areas. In the early 1990s, its total length was 73,000 km (the length of the earth's equator is about 40,000 km). The same motorway systems are available in many other countries ("autobahns" in Germany, "Autostrada del Sole" in Italy).
The device of the road.  The highway has a subgrade, a base, one or more roadway coatings (road pavement), curbs, bridges, drainage devices and regulatory tools traffic.

  The base (with the underlying coating) is made of building soil and transfers the loads from passing cars in a dispersed form to the subgrade. The coverings of the roadway may consist of asphalt concrete, crushed stone, crushed stone with bitumen impregnation, concrete on Portland cement, gravel or impregnated soil.
see also DESIGN AND CONSTRUCTION MATERIALS. The shoulder provides lateral support for the pavement. Roadsides are provided on the right side of the first lane in each direction. They also serve as an emergency stop. Bridges and overpasses make it possible for motor vehicles to pass over obstacles encountered on the way - water spaces, transverse roads, railways, etc. Drainage is necessary for the removal of storm flows and spring water. Culverts are laid in suitable places under the pavement, and water is drained through ditches or pipes to the gutter. Means of regulation of movement provide safety and orderliness of movement. Such means include signs and road signs, marking lines applied to the carriageway, traffic lights, traffic intersections at the intersection of roads at different levels and crossings at the intersection with the railway at the same level.
Types of pavement.  Road clothes of different durability for different permissible load can be obtained by combining various road-building materials. The most important thing for the durability of good pavement is the drainage and compaction of its lower layers. Water in a road bed contributes to subsidence and lateral creeping, and can also cause swelling due to freezing or expansion of some types of clay. A road engineer knows which materials are easier to drain and which drainage system is more economical. Sometimes, during road construction, it is necessary to take out natural soil to a considerable depth and replace it with granular factory-made material. All loosened and added road building materials must be compacted in thin layers. To do this, heavy steel rollers with small teeth moved by tractors are used. There are also vibratory rollers. Especially careful compaction is required by coastal foundations of bridges and places of underground passages of communications.
Dirt roads.  The simplest road can be built by smoothing out the irregularities of the natural soil and giving the roadway the required profile. It is enough to cut off the hillocks, fill the hollows and dig out the drainage ditches on the sides to get a good, cheap way for not very heavy traffic. However, dirt roads become impassable due to dirt in rainy weather and due to dust to dry.
Gravel road. Gravel pavements are somewhat more durable, to which soil of a certain quality is added as a binder. To increase the waterproofness and durability of the road surface, gravel is impregnated with bitumen. This can significantly increase the durability of roads with a small load, if timely potholes close up. It is also possible to cover bitumen with dirt and gravel roads.
Stabilized soil.  A road surface that is quite resistant to seasonal changes in humidity and temperature can be obtained by adding sand to clay or clay to sand, or by applying another combination of local soil. Portland cement, carefully mixed with some types of soil, gives a coating that is quite suitable for moderately loaded roads. When preparing the material for a cement-cement coating, the soil is completely crushed, and then thoroughly mixed in place with 6-10% cement to a depth of 10 cm or more. The roadbed is given the desired shape and compacted by rolling. Bitumen is applied in a thin layer to the surface to prevent drying before cement sets. In some places, the surface of the road can be economically strengthened with bitumen by thoroughly mixing it with the existing soil to a depth of 10-25 cm. The cement-soil and bitumen-soil layers are excellent as a base and underlay for pavement. Since the surface is damaged mainly by fast-moving cars, it makes sense to protect it with a layer of wear to save money.
Macadam. Macadam, a pavement named after its inventor, English engineer J. Macadam (1756-1836), is a few layers of strong crushed stone, carefully compacted with a heavy roller and joined into a solid mass with very small crushed stone rolled on top. The result is a very strong layer. When rolling it is watered with water, which further increases the strength of the coating. In the United States, macadam is more often understood as paving with bitumen. There are hundreds of kilometers of bitumen-gravel roads, especially in New England, where strong rocks are abundant. Such pavement should consist of at least two layers on a rigid base. The thickness of each layer should be slightly larger than the maximum size of the crushed stone, so that large pieces of crushed stone wedged between smaller ones, increasing the strength of the layer. The layers can be 4-10 cm thick, and bitumen is consumed 5-15 l / m2. The crushed stone of each layer is evenly stacked by the machine and rolled. Then the bitumen distribution machine pours it with heated bitumen. Fine crushed stone is poured on top and rolled on hot material. The second layer is laid in the same way, making sure that a smooth surface is obtained.
Asphalt roads.  Modern smooth asphalt pavement (sheet asphalt) consists of sand, stone (rubble) flour and asphalt, carefully selected according to the particle size distribution. The materials are mixed by the mixing unit at a temperature of approx. 175 ° C, at which the asphalt is in a molten state, the mixture is delivered into place, applied by a special machine to the roadway and rolled in a hot state.

  Asphalt concrete coating consists of layers 5-7.5 cm thick of the mixture (prepared at a temperature of about 175 ° C) taken in the right proportion of crushed stone of different sizes, sand, stone flour and molten asphalt as a binder. Asphalt concrete and smooth sheet asphalt are laid on the base of macadam or Portland cement concrete, designed for the appropriate road loads. High quality asphalt pavement It is carried out on a reliable foundation with an underlying layer of classified material or macadam and 2-5 layers of asphalt. In the lower layers, crushed stone is larger, which increases the strength of the coating and gives savings, and in the upper layers it is finer, which ensures water resistance and wear resistance of the surface. However, the road surface should be somewhat roughened to prevent tire slippage and to facilitate the displacement of water by the tread. The full thickness of the road surface depends on the bearing capacity of the soil and the estimated transport load. Asphalt can be mixed with crushed stone poured on the roadbed directly at the construction site, and then leveled and rolled. But it is more preferable to use factory-made hot mixtures in which the proportions of the ingredients are precisely maintained. At the plant, crushed stone is dried and heated in a rotary kiln, and then separately heated asphalt is added to it, and all these elements are mixed. For the preparation of high-quality coatings, temperatures not lower than 165 ° C are desirable. The hot factory mixture is quickly delivered to the place, laid flat on the roadway, and then compacted with vibration and rolling.
Portland cement coating. The base and wear layer of such a coating are usually combined into one layer, which is stacked in one operation. When laid on a properly prepared underlay, Portland cement gives an excellent road surface. High wear resistance and coating strength is achieved when 1 part of cement is taken in 2 parts of sand and 3-4 parts of gravel or gravel. If you use Portland cement as a base for asphalt concrete, you can take more sand and coarse aggregate, but less cement, and thereby reduce the cost of pavement. The thickness of the concrete pavement of roads and streets can be 20-25 cm, while on runways of aerodromes with heavy loads it often reaches 35 cm. At the edges of the roadway, a coating at a width of 0.6-1.2 m is made at 7.5 -10 cm thicker to increase road durability at minimal total cost. Concrete is laid at full thickness in one operation. If reinforcing wire mesh is used, then a 5-cm layer of concrete is first laid, and then, laying the mesh, fill the formwork to the end. During the construction of the road, concrete is laid at a width of 6-9 m, corresponding to two lanes. In the middle of this width, a temperature-shrink seam is usually provided, since otherwise a meander crack arises here. Concrete for paving can be kneaded at the factory and delivered to the place wet; in other cases, the mixture is made at the factory, and kneaded along the way or in place by a concrete mixer. To obtain high-quality coatings, the moisture content of the filler and the proportion of each component of the mixture are carefully controlled. A soil or granular base for concrete coating is precisely profiled, and then steel formwork of the required depth is set in the form of hard edges of the carriageway to be concrete. Concrete is applied to the base and leveled by the machine. Concrete distribution machine moves along the formwork, as on rails. It is followed by a finisher with vibrators, compacting concrete, and rollers, leveling its surface. The surface is checked manually with a straightedge and adjusted if necessary. In conclusion, it ends with pulling a special tape or burlap along it to roughen it. So that for at least a week, before the concrete sets, the surface does not dry out, it is covered with a composition that prevents evaporation, or covered with burlap, which is regularly moistened.
Modern technology. Roads and bridges must be repaired or reconstructed as needed. The service life of roads is 20-30 years, bridges - from 50 to 100 years.

  Modern technology allows you to more efficiently manage roads, plan and design them, build and operate. Computer-aided design systems, as well as computer-based data processing systems used in all areas of road construction and operation, have gained importance. Advances in modern technology, such as infrared thermography and soil penetrating radar, make it possible to identify structural and physical defects in roads and bridges. An increasingly important role in the regulation of road traffic is played by electronics. Thus, the development of electronic vehicle control systems with a map on the dashboard and voice alarm systems and automated traffic control systems in central urban areas is underway.
see also    Introduction SECTION I BASES OF TECHNOLOGY AND ORGANIZATION OF CONSTRUCTION OF ROADS CHAPTER 1. Stages of development and ways to improve the network of roads and the technology of their construction 1.1. The main stages of development and improvement of the road network of Russia 1.2. The role of scientists in creating the scientific and technical base of road construction 1.3. Development and improvement of technology and methods for the construction of roads 1.4. Ensuring the strength and performance of road structures SECTION II ESTABLISHMENT OF THE EARTH CANVAS CHAPTER 2. Constructions of the subgrade and requirements for its construction 2.1. Requirements for the construction of the subgrade 2.2. Requirements for soil subgrade 2.3. Technology of works on the construction of subgrade 2.4. Basic principles of planning and organization of work 2.5. Soil compaction CHAPTER 3. Preparatory work before the construction of the subgrade 3.1. Composition and purpose of preparatory work 3.2. Removing plant soil and preparing the foundation of the subgrade CHAPTER 4. Construction engineering structures  to regulate the water-thermal regime of the subgrade 4.1. Types of structures and methods for regulating the water-thermal regime of the subgrade and road clothes 4.2. Construction of waterproof and capillary interruption layers. Preparation of the upper part of the subgrade before the installation of additional base layers. CHAPTER 5. The construction of embankments and the development of excavations in non-rocky soils 5.1. Methods of filling embankments and excavation 5.2. The construction of embankments from the soil excavations 5.3. Construction of embankments from the soil of lateral reserves Chapter 6. Construction of the subgrade on slopes. Planning and strengthening slopes 6.1. The main types of subgrade designs on slopes and landslide slopes 6.2. Features of the construction of the subgrade on slopes and landslide slopes 6.3. Layout of the subgrade of embankments and excavations, cones and slopes 6.4. Strengthening cones and slopes earthworks   CHAPTER 7. Construction of a subgrade in mountain conditions 7.1. Features of the construction of the subgrade in the highlands 7.2. Drilling and blasting. Safety precautions 7.3. Calculation of blasting 7.4. The technology of excavation in rocky soils. Quality control 7.5. Construction of landslide-fighting structures CHAPTER 8. Hydromechanization of earthworks 8.1. Conditions and effectiveness of the application of hydromechanization of earthwork 8.2. Transportation and laying of soil. General organization of work CHAPTER 9. Construction of the subgrade in difficult engineering and geological conditions 9.1. Construction of the subgrade on weak foundations 9.2. The construction of high embankments and deep excavations 9.3. Construction of the subgrade in sandy deserts 9.4. Construction of subgrade on saline soils 9.5. Construction of the subgrade in areas of permafrost distribution 9.6. The construction of a subgrade of clay soils with a moisture content of more than optimal 9.7. Construction of embankments from industrial soils CHAPTER 10. Construction of the subgrade using geosynthetics 10.1. The concept of geosynthetics. Fields of their application * 10.2. Brief classification of geosynthetics for road construction 10.3. Construction of the subgrade using geosynthetics CHAPTER 11. Construction of the subgrade in winter period 11.1. Features of the organization and production technology of works on the construction of the subgrade in the winter 11.2. Construction of the subgrade of embankments and excavations 11.3. The device of additional sandy layers of the bases 11.4. Features of the construction of small artificial structures in the winter CHAPTER 12. Reconstruction of the subgrade 12.1. The working conditions of the existing subgrade and the main ways to increase its strength and stability 12.2. Preparatory work for the reconstruction of the subgrade 12.3. Ways of broadening embankments and excavations. Requirements for the selection, placement in layers and compaction of the soil subgrade broadening 12.4. Correction of the longitudinal profile. Increase in height of embankments and depth of excavations 12.5. Reconstruction of heaving sections 12.6. Improving the stability of slopes of the reconstructed subgrade and improving the drainage system 12.7. Reconstruction and lengthening of culverts CHAPTER 13. Organization of works on the construction of subgrade 13.1. General provisions 13.2. Determination of the composition of specialized detachments and the optimal capture length during the preparatory work and the construction of culverts 13.3. Determination of the composition of specialized units and the optimal length of the grapple during the construction of the subgrade SECTION III CONSTRUCTION OF ROAD CLOTHES Chapter 14. Fundamentals of the technology of construction of road pavements 14.1. Technological classification of pavements, coatings and substrates 14.2. Ensuring the reliability of pavement 14.3. Fundamentals of technology for sealing layers of pavements CHAPTER 15. Construction road bases and coatings of untreated stone materials and stone materials and soils treated with inorganic binders 15.1. Development of methods for the use of soils and local stone materials in pavement layers 15.2. Construction of layers of crushed stone materials 15.3. Construction of layers of crushed stone and sand and other mixtures 15.4. Construction of layers from active industrial wastes 15.5. Construction of layers of materials treated with cement 15.6. Cobblestone, mosaic and clinker bridges 15.7. Fundamentals of the technology for the production of artificial granular material from clay soils using electroplasma devices 15.8. Technology and effectiveness of the use of granular ceramic materials in the construction of pavement bases CHAPTER 16. Construction of road bases and coatings from stone materials and soils treated with organic binders 16.1. Construction of crushed stone layers by impregnation 16.2. Construction of layers of black gravel 16.3. Construction of layers from mixtures of stone materials with liquid organic binders 16.4. Construction of layers from mixtures of stone materials with viscous organic binders 16.5. Construction of structural layers of pavement from emulsion-mineral mixtures 16.6. Construction of layers from soils reinforced with organic binders CHAPTER 17. Construction of cement concrete coatings and foundations 17.1. Features of the construction of coatings using mineral binders 17.2. Requirements for materials for the construction of cement concrete pavements and design of the composition of road concrete 17.3. Designs of cement concrete pavements and foundations 17.4. Technology for the construction of cement-concrete coatings 17.5. Construction of monolithic reinforced concrete and continuously reinforced coatings 17.6. Construction of prestressed monolithic cement concrete coatings 17.7. Construction of foundations and coatings of rolled concrete 17.8. Features of the construction of cement concrete coatings at low temperature  air 17.9. Construction of prefabricated and precast monolithic coatings 17.10. Quality control of the construction of cement-concrete coatings CHAPTER 18. Construction asphalt concrete pavement and grounds 18.1. General provisions of the technology for the construction of asphalt concrete pavements 18.2. Designs of road pavements with asphalt concrete pavement 18.3. Design of the composition of asphalt mixtures 18.4. Meeting the requirements for the physicomechanical properties of asphalt concrete 18.5. Construction technology of asphalt concrete pavements and foundations 18.6. Requirements for the composition of technological maps for the construction of asphalt concrete coatings CHAPTER 19. Construction of asphalt concrete coatings from cold and cast mixtures  and crushed stone mastic asphalt concrete 19.1. Construction of coatings from cold asphalt mixtures 19.2. Construction of coatings from cast asphalt concrete mixtures 19.3. Construction of coatings from crushed stone and mastic asphalt concrete 19.4. Construction of coatings from asphalt mixtures based on polymer-bitumen binders 19.5. Construction of asphalt concrete pavements at low air temperature 19.6. Labor protection during the construction of asphalt concrete pavements CHAPTER 20. Construction of wear layers, protective rough layers 20.1. Appointment of wear layers, protective and rough layers 20.2. Surface treatment pavement   20.3. Surface treatments with polymer binder 20.4. The device of a rough wear layer by the method of crushed stone embedding 20.5. Wear and protective layers using emulsion-mineral mixtures CHAPTER 21. Construction of road pavements with the simplest type coatings 21.1. Purpose of coatings of the simplest type 21.2. Local soils as a coating material of the simplest type 21.3. The technology of construction of the simplest coatings from artificially improved soils 21.4. Profiling technology dirt roads 21.5. Construction of wooden, continuous and gauge coatings (bench and log) 21.6. Cobblestone, mosaic and clinker bridges CHAPTER 22. Reconstruction of pavement 22.1. Methods of reconstruction of pavement 22.2. Methods for disassembling layers of pavement for reuse of their materials 22.3. Methods for the regeneration of pavement and pavement 22.4. Broadening of pavement 22.5. Reinforcement of existing pavement 22.6. Features of reconstruction of pavements with cement concrete pavements 22.7. Arrangement of edge strips and roadside reinforcement during road reconstruction 22.8. Reconstruction of pavement of transitional type SECTION IV MATERIAL AND TECHNICAL SUPPORT OF ROAD CONSTRUCTION Chapter 23. Enterprises for the development of rocks 23.1. Development of rocks 23.2. Features of the development of rock 23.3. Features of the development of clastic rocks 23.4. Processing of stone materials in road quarries at mobile crushing and screening plants CHAPTER 24. Stone crushing plants 24.1. The main processes of stone crushing plants 24.2. KDZ Master Plan 24.3. Processing of gravel and sand materials 24.4. Preparation of crushed sand 24.5. Production of mineral powder for asphalt concrete 24.6. Features of the organization of finished goods warehouses 24.7. Technological processes of enrichment and improvement of stone materials 24.8. Quality control, acceptance of finished products CHAPTER 25. Bitumen and emulsion bases 25.1. Appointment and placement of bases and warehouses 25.2. Technological processes for the preparation of organic binders 25.3. Emulsion bases and workshops. Technology for the production of bitumen emulsions 25.4. Plants for the production of cationic bitumen emulsions 25.5. Automation technological processes  on emulsion bases and quality control of emulsions CHAPTER 26. Factories for the preparation of asphalt mixtures 26.1. Classification of plants and features of their location 26.2. The master plan of the ABZ 26.3. Technological processes. The choice of technological equipment 26.4 Asphalt mixing plants 26.5. Processing of old asphalt concrete (regeneration) at ABZ 26.6. Process Automation asphalt plant and quality control 26.7. Bases and installations for treating soils with binders CHAPTER 27. Factories for the production of cement-concrete mixtures 27.1. Classification of plants and features of their location 27.2. The general plan of the pulp and paper mill 27.3. Technological processes of production and equipment 27.4. Features of the organization of stone materials warehouses 27.5. Warehouses of cement and mineral powder 27.6. Automation of technological processes and product quality control 27.7. Equipment for transportation of concrete mixtures 27.8. Features of the pulp and paper mill in winter and in hot climates CHAPTER 28. Factories and landfills for manufacturing reinforced concrete products   28.1. Classification of factories and landfills and product manufacturing technology 28.2. Methods for the production of reinforced concrete products 28.3. Quality control of reinforced concrete products and features of the organization of the warehouse of finished products CHAPTER 29. Labor and environmental protection at production enterprises road facilities 29.1. General provisions on labor protection and safety in the construction industry 29.2. Labor protection and safety measures at production enterprises (bases) of road construction 29.3. Environmental protection at road construction manufacturing enterprises SECTION V ORGANIZATION OF ROAD CONSTRUCTION WORKS Chapter 30. Main issues of the organization of road construction works 30.1. General provisions for the organization of the construction of the road 30.2. Features of the organization of work during the reconstruction of the road 30.3. Organizational and technical measures for environmental protection during the construction (reconstruction) of the road 30.4. Labor protection and safety during the construction of roads CHAPTER 31. Organization of the production base of road construction 31.1. Organization of material and technical support for road construction 31.2. Organization of storage facilities in road construction 31.3. Organization of maintenance and repair of machines 31.4. Providing the production base of road construction with electricity, compressed air, steam, water and technological communications CHAPTER 32. Methods of organizing road construction works 32.1. The complex mechanized in-line method and its variants 32.2. Non-stream methods of organizing road construction works CHAPTER 33. Designing the organization of construction and production of road construction works 33.1. The project of the organization of construction and the project of the production of works 33.2. Determination of the composition of specialized units in the construction of pavement 33.3. Drawing up calendar, network, hourly schedules for the construction of roads and technological maps 33.4. Determination of construction needs in material and technical resources 33.5. Supervisory control and automation of construction management SECTION VI. QUALITY ASSURANCE OF ROAD CONSTRUCTION WORKS CHAPTER 34. Quality control of road construction works 34.1. The system of control and quality management of road construction works 34.2. Organizations and technology for quality control of road construction works Chapter 35. Production quality control of road construction works 35.1. Quality control of the work performed during the construction of the subgrade and the rules for their acceptance 35.2. Operational control in progress and upon completion of related operations 35. 3. High-speed methods for monitoring the strength and evenness of pavement 35.4. Controlled parameters, means of control, tolerances and scope of measurements during operational and acceptance control CHAPTER 36. Statistical control and quality control during the construction of roads 36.1. The relevance of statistical control methods in road construction 36.2. Substantiation and development of a single accounting apparatus for statistical quality control in road construction 36.3. Methodological basis for quality assessment in road construction 36.4. Methodology for determining the volume and measurement points for statistical control 36.5. Processing the results of statistical control and quality assessment 36.6. Adjustment of technological processes at the preparation stage and during the construction process 36.7. Examples of organizing and conducting statistical control, quality assessment and tuning of technological processes 36.8. Main conclusions SECTION VII PRODUCTION AND TECHNOLOGICAL PARAMETERS OF MACHINES AND EQUIPMENT FOR CONSTRUCTION AND RECONSTRUCTION OF ROADS Chapter 37. Selection and determination of the main production and technological parameters of road-building equipment 37.1. The main trends in the development of road-building machines and their production and technological parameters 37.2. Main technological parameters for the main groups of machines and equipment and determination of productivity CHAPTER 38. Machines and equipment for the construction of subgrade 38.1. Machines for preparatory work 38.2. Machines for the development and transportation of soil 38.3. Machines for leveling the ground and planning the subgrade and base layers and slopes 38.4. Machines and equipment for compaction of soils CHAPTER 39. Machines and equipment for the construction and reconstruction of pavements 39.1. Machines for the construction of base layers from soils and mineral materials treated with binders 39.2. Machines for the construction of base layers of crushed stone and gravel 39.3. Machines for the construction of asphalt concrete pavements 39.4. Machines and equipment for the construction of cement concrete coatings 39.5. Machines and equipment for the construction of wear layers (protective layers) of the coating 39.6. Machines for sealing base layers and coatings 39.7. Cars for arrangement of roads 39.8. Machines and equipment for road reconstruction References