ODM 218.3.060-2015

INDUSTRY ROAD GUIDELINE

Foreword

1 DEVELOPED by the Federal State Budget educational institution higher professional education "Moscow Automobile and Highway State Technical University (MADI)"

2 INTRODUCED by the Department of Scientific and Technical Research and Information Support of the Federal Highway Agency

5 INTRODUCED FOR THE FIRST TIME

1 area of ​​use

1 area of ​​use

2 Normative references

Thermal cracks occur as a result of cooling and resistance of the coating to thermal shrinkage. Vertically, these cracks develop from top to bottom, from the surface of the coating to the base.

Fatigue cracks that occur when a monolithic layer is bent from multiple transport loads develop from bottom to top from the base to the surface of the coating.

Reflected cracks replicate seams or cracks in cement concrete pavements and are most characteristic of asphalt concrete layers laid on a cement concrete pavement. With a decrease in temperature, the deformation of the cement concrete coating occurs in the form of a shortening of the slabs. As a result, joints or cracks in the cement concrete pavement expand, which leads to stretching and rupture of the overlying layers of asphalt concrete with the formation of reflected cracks. To these tensile stresses are added their own tensile stresses from a decrease in the temperature of the asphalt concrete. This is a time cyclic process leading to the destruction of the asphalt concrete pavement.

By width, cracks are classified into narrow (up to 5 mm), medium (5-10 mm) and wide (10-30 mm). This classification is typical for thermal and fatigue cracks. For reflected cracks, this approach is incorrect, due to the presence of thermal deformations of the underlying cement concrete pavement causing the crack edges to move depending on temperature, the length of the cement concrete slab, the thickness of the asphalt concrete pavement and other factors.

Depending on the width and type of cracks, the technology of their repair and the composition of the equipment used are selected. The main task in the repair of cracks is to prevent the penetration of water through them into the underlying layers of the pavement. Waterproofing of cracks is achieved by sealing them with special mastics and repair mixtures.

6.1.3 When choosing mastics, it is necessary to focus on their main physical and mechanical properties. One of the most important indicators for choosing mastics is adhesive strength, the requirements for which must comply with GOST 32870-2014.

6.1.4 Sealing narrow temperature or fatigue cracks on the surface of asphalt concrete layers laid on a cement concrete pavement does not require complex technological operations. Cracks are cleaned by blowing with compressed air, dried, heated and filled with bituminous emulsion or mastic with high penetrating power.

6.1.5 On thin temperature or fatigue cracks (2-5 mm), heated polymer-bitumen mastic can be applied in the form of a tape that prevents the coating from chipping at the edges of the crack. It is smoothed out with a special heating iron (shoe) and sprinkled with fractionated sand. The coating in the crack zone is preliminarily dried with a heated jet of compressed air.

6.1.6 If the crack has destroyed edges, the repair technology should begin with the operation of cutting it, that is, artificial expansion of the upper part of the crack with the formation of a chamber in which the sealing material performs optimally in tension during the crack opening.

6.1.7 The width of the chamber must not be less than the destruction zone of the crack edges. To create the best working conditions for the sealant in the chamber, the ratio of the width and depth of the chamber is usually taken as 1:1. In addition, when determining the geometric dimensions of the chamber, it is necessary to take into account the maximum possible crack opening and the relative elongation of the sealing material used. Typically, the width of the chamber is in the range of 12-20 mm.

6.1.8 If the temperature or fatigue crack is not cut to the full depth (the thickness of the cracked coating exceeds 10 cm), then before sealing, a special sealing cord made of an elastic material that is thermally and chemically resistant to the sealant and the environment is placed in the crack at the bottom of the chamber. When using a sealing cord for pressing in, it must be taken into account that its diameter should be 1.2-1.3 times the width of the chamber of the split crack.

The depth of the groove after pressing the sealing cord (upper free part of the chamber) is taken depending on the properties of the sealant.

Instead of a sealing cord, a layer of bituminized sand or a layer of rubber crumb laid on the bottom of the chamber, with a thickness equal to an average of 1/3 of its depth, can also be used, after which the chamber is filled with sealant.

When bituminized sand is used, coarse and medium sand is used that meets the requirements of GOST 8736-2014 and GOST 11508-74 *.

Rubber crumb must have particle sizes in the range of 0.3-0.5 mm and meet the requirements *.
________________
* See section . - Database manufacturer's note.

Depending on the stickiness temperature and the resistance of the sealant to wear under the influence of car wheels, it should be filled with underfilling, flush or with the formation of a patch on the surface of the coating.

6.1.9 In the case when the edges of a temperature or fatigue crack have not been destroyed and it is possible to seal the crack without cutting it, this operation can be excluded from the technological process.

6.1.10 The most important condition ensuring the quality of crack sealing is the presence of good adhesion of the sealant to the walls of an uncut crack or a milled chamber. As a result, much attention is paid to preparatory work for cleaning and drying cracks. To improve adhesion, the walls of the milled chamber are primed with a primer - a low-viscosity film-forming (gluing) liquid.

6.1.11 The main technological operation in the repair of temperature or fatigue cracks is their filling with hot mastic. The mastic is preheated to a temperature of 150-180°C, after which it is fed into an arranged chamber or directly into the crack cavity. In this case, depending on the equipment used, it is possible to seal either the crack itself, or, simultaneously with filling with mastic, arrange a plaster on the surface of the coating in the crack zone. Such a patch 6-10 cm wide and 1 mm thick makes it possible to strengthen the edges of the crack and prevent their destruction.

Sealing with a plaster is advisable to use for cracks with significant destruction of the edges (10-50% of the crack length), because. in this case, the defects on the coating surface in the crack zone are healed.

The method of rehabilitation of medium and wide temperature or fatigue cracks in asphalt concrete layers laid on cement concrete is divided into five stages:

1. Cutting cracks. In this case, special crack separators are used. To avoid edge damage when cutting a crack in an asphalt concrete pavement, it is necessary to take into account the composition of asphalt concrete when choosing a cutting tool. With a grain size of crushed stone of 20 mm or more, it is recommended to use a diamond tool, and with a grain size of up to 20 mm, cutters with hard facing can be used.

2. Removal of destroyed asphalt concrete. For this, a high performance compressor is used. For thorough cleaning both from the dust that appeared as a result of cutting, and to remove deposits remaining in the depth of the crack.

3. Drying and warming up. The split cavity of the crack is dried and heated by the so-called thermal spear.

The parameter for stopping the heating is the appearance of melted bitumen cracks on the walls. In no case should the crack be overheated, bitumen burning will lead to a sharp decrease in adhesion and further destruction of the coating around the crack.

In this regard, crack heating with open flame burners is unacceptable.

4. Filling the crack cavity with sealant. Bituminous mastic is immediately fed into the cleaned, dried and heated cavity of the cut crack from the melting and pouring machine.

Modern pourers in general form are a heated tank mounted on a frame equipped with a wheel drive. Heating can be carried out by means of an oil coolant, gas or a burner with diesel fuel. The sealing material is loaded into the tank, where it is heated to the operating temperature, and then, using a pump, it is fed into the prepared crack through heat-resistant hoses.

Direct sealing of cracks is carried out through various nozzles, the size of which depends on the width of the crack being filled. If necessary, the filling nozzle can be equipped with shoes for installation on the surface of the coating in the area of ​​the crack in the mastic patch.

To reduce the dynamic load on the seam, and reduce the adhesion of the sealant to the wheel of a passing car, it is necessary to fill only the inner cavity of the crack without spilling on the edges.

5. Powder. Immediately after filling the crack with sealant, the repair site is covered with sand or a mixture of fine gravel with mineral powder from above.

6.1.12 For powdering, special equipment is used - a distributor. The equipment is a bunker mounted on three wheels. Moreover, the front, piano wheel allows you to move exactly in the direction of the crack, and a dosing roller is mounted on the axis of the rear wheels inside the hopper. The distributor is moved manually along the sealed crack, immediately behind the filler, while the wheels rotate the roller, dosing crushed sand or fine gravel onto the surface of the mastic poured into the crack.

The powder serves to restore the overall texture and roughness of the coating, prevents the mastic from sticking to the wheels of the car, and reduces the fluidity of the sealant immediately after the crack is filled.

6.1.13 When carrying out work on the rehabilitation of cracks, it is necessary to ensure the continuity of the technological process. Permissible gaps in time between individual technological operations should not exceed the following values: 1 - crack cutting - up to 3 hours; 2 - crack cleaning - up to 1 hour; 3 - heating of the side walls of the crack - up to 0.5 min; 4 - crack sealing - up to 10 min; 5 - powdering the surface of the sealant with sand or fine gravel with mineral powder.

6.1.14 Crack repair technology is implemented by a set of equipment consisting of:

Crack splitter with a diamond tool with a pavement aggregate size of more than 20 mm, with a filler size of up to 20 mm, cutters with hard-alloy surfacing are used;

A mechanical brush or a wheeled tractor with a mounted brush (in the case when it is necessary to rehabilitate sufficiently wide and heavily contaminated cracks, they can be cleaned with disc brushes with metal bristles, brushes with a disc with a diameter of 300 mm and a thickness of 6, 8, 10 or 12 mm, the thickness should be 2-4 mm less than the width of the crack to be cleaned);

compressor;

Gas generator installation or thermal lance. The principle of operation of the thermal lance is based on the fact that compressed air from a compressor with a capacity of 2.5-5.0 m/min at a pressure of 3.5-12 kg/cm is mixed with natural gas and enters the combustion chamber in the form of a gas-air mixture, where it is ignited . Air heated to a temperature of 200-1300°C is fed through a nozzle at a speed of 400-600 m/s into the treated crack zone. The gas consumption in this case is 3-6 kg/hour. A high-speed compressed air flow, in addition to heating, effectively cleans the cavity of the crack itself and, in addition, pulls out individual destroyed particles of the coating from the area adjacent to the crack;

Melting and pouring machine mounted on a car chassis;

Equipment for filling a sealed crack.

6.1.15 When repairing reflected cracks, first of all, it is necessary to establish whether the repaired crack belongs to the reflected type. Visually reflected cracks are easy to distinguish from temperature and fatigue cracks, as they pass over the joints of the underlying cement concrete pavement, as if "copying" them.

If there are cracks in the cement concrete itself, then on the surface of the asphalt concrete layer such reflected cracks can be established using GPR survey.

6.1.16 One way to repair reflected cracks is to artificially expand its upper part to form a chamber with a width that takes into account the maximum possible crack opening (as a rule, at least 1 cm) and the relative elongation of the sealing material used.

The technology for the production of repairs of this type is considered in paragraphs 6.1.6-6.1.8.

6.1.17 Another method is to repair reflected cracks using reinforcing geogrids in combination with solid non-woven geotextiles. In this case, the geogrid is included in the tensile work during bending, preventing the crack from opening, and the geotextile acts as a damping layer that perceives stresses that arise in the crack zone during temperature movements of cement concrete slabs.

The following requirements are imposed on the geogrid: it must have high thermal stability, low creep at sufficiently high temperatures for laying the asphalt concrete mixture (120-160°C) and good adhesion to bitumen. Cell sizes are taken depending on the composition of the asphalt mix and ensuring good adhesion between the layers of the coating (about 30-40 mm when using hot asphalt mixes on viscous bitumens).

The following requirements are imposed on the non-woven interlayer of geotextiles: the density of the interlayer should be no more than 150–200 g/m, the tensile strength is 8–9 kN/m, and the relative elongation at break is 50–60%.

6.1.18 Repair of reflected cracks using reinforcing geogrids in combination with non-woven geotextiles is carried out according to the following technology:

Organization traffic at the work site, installation of fences;

Cleaning the coating from dust and dirt;

Milling of the existing asphalt concrete pavement in the crack zone to a width of 30-50 cm and to the depth of the repaired layer (but not less than 5 cm);

Priming of the milled surface of asphalt concrete with cationic bitumen emulsion in an amount of at least 1 l/m in terms of bitumen;

Laying a layer of geotextile to a width of 30 cm strictly symmetrical to the axis of the crack being repaired (when laying a strip of geotextile, its pre-tension should be at least 3%. The sheet is stretched by 30 cm with a strip length of 10 m);

Laying a layer of coarse-grained asphalt concrete mixture on the geotextile layer to the width of the milled crack, followed by layer-by-layer compaction with a layer thickness of 5-6 cm. existing coverage;

Priming the surface of the laid layer of asphalt concrete with a bitumen emulsion in an amount of at least 0.6 l/m2 in terms of bitumen for a geogrid laying width of 150-170 cm;

Laying the geogrid sheet strictly symmetrically to the axis of the crack being repaired;

Repeated pouring of the binder over the entire width of the coating surface;

Laying and compaction of the top layer of the coating of dense fine-grained asphalt concrete mixture with a layer of at least 5-6 cm over the entire width of the repaired coating.

6.1.19 One of the ways to repair reflected cracks is their sanitation with crack filling with hot fine-grained asphalt concrete mixture with bitumen-rubber binder. This makes it possible to largely extinguish the stresses arising above the joints of the cement concrete pavement and absorb internal plastic deformations. Rubber crumb in the composition of the binder acts as particles of the polymer component, which carry out the dispersion-elastic reinforcement of asphalt concrete.

Asphalt concrete mixtures based on bitumen-rubber binder should be designed, depending on the type and purpose of asphalt concrete, in accordance with GOST 9128.

Technical requirements for composite bitumen-rubber binders must comply with the established requirements.

For a composite bitumen-rubber binder, viscous oil road bitumen grades BN, BND according to GOST 22245 and liquid bitumen grades MG and MGO according to GOST 11955 are used as initial ones.

Finely dispersed rubber crumb is used, which is a crumb of general-purpose rubber, including rubber obtained by crushing worn-out car tires or other rubber-technical products. The crumb must have a particle size in the range of 0.3-0.5 mm and meet the requirements.

6.1.20 The technology of repairing reflected cracks using hot fine-grained asphalt concrete mixture with a bitumen-rubber binder includes the following technological operations:

Crack cutting;

Mechanical cleaning of the crack;

Blowing out the crack with compressed air;

Heating of the side walls of the crack, priming of the bottom and walls of the crack;

Crack filling with hot fine-grained asphalt concrete mixture with bitumen-rubber binder;

Compaction of asphalt mix.

For compaction, a small-sized roller or vibrating plate is used.

The temperature of the asphalt concrete mixture on bitumen BND 40/60, BND 60/90, BND 90/130, BND 130/200, BND 200/300 with bitumen-rubber binder at the beginning of compaction should not be lower than 130-160 ° C for dense asphalt concrete types A and B and high-density asphalt concrete.

6.1.21 Technological sequence of work, when repairing potholes, consists of the following operations: cleaning the asphalt concrete pavement from moisture, dirt and dust at the work site; border marking repair work in straight lines along and across the axis of the road with a 3-5 cm grip on the undestroyed pavement (if several closely spaced potholes are being repaired, they are combined with one contour or map); cutting═ cutting or cold milling of repaired asphalt concrete along the outlined contour to the entire depth of the pothole═ but not less than the thickness of the asphalt concrete layer. In this case, the side walls must be vertical; cleaning the bottom and walls of the repair site from small pieces═ crumbs═ dust═ dirt and moisture; treatment of the bottom and walls with a thin layer of liquid (hot) or liquefied bitumen or bitumen emulsion, laying the asphalt concrete mixture; leveling and compaction of the coating layer.

6.1.22 In the event of the formation of chips in the cement concrete pavement slabs, the pothole formed as a result of this in the overlapping asphalt concrete layer can be significant in depth (more than 20-25 cm). Repair of such areas must be carried out with the removal of the destroyed layer of asphalt concrete to the full thickness, to the width of the surface of the chipped cement concrete slab. Repair of a chipped surface of a cement concrete slab must be carried out in accordance with. After that, the asphalt concrete mixture is laid and compacted.

6.1.23 For patching of an asphalt concrete layer laid on a cement concrete pavement, it is recommended to use mainly hot mix asphalt or cast asphalt concrete of types I and II in accordance with the requirements of GOST 9128-2013 and GOST R 54401-2011, respectively.

It is recommended to use asphalt concrete mixtures corresponding in terms of strength, deformability and roughness to the asphalt concrete of the existing pavement. Hot fine-grained mixtures of types B and C should be used, since they are more technologically advanced for work with shovels, rakes and trowels in auxiliary operations than multi-gravel mixtures of type A.

For the preparation of hot fine-grained asphalt concrete mixtures, viscous road bitumen BND 40/60, BND 60/90, BND 90/130, BND 130/200, BND 200/300 according to GOST 22245, as well as modified, polymer-bitumen binders according to OST 218.010- 98 .

6.1.24 To perform edge trimming, small milling machines, circular saws, and perforators are used.

Depending on the area of ​​the repaired area, trimming of the coating is performed in various ways. Small areas (up to 2-3 m) are contoured using a seam saw equipped with special thin (2-3 mm) diamond discs with a diameter of 300-400 mm. Then, with jackhammers, the coating inside the circuit is disassembled. The asphalt crumb is removed and the site is prepared for laying the asphalt concrete mixture.

6.1.25 When preparing for the repair of long narrow potholes or sections of more than 2-3 m, it is advisable to use permanently installed, trailed or mounted cutters that cut off defective coating material 200-500 mm wide to a depth of 50-150 mm.

If the area is large, then special high-performance road milling machines with a large width of cut material (500-1000 mm) and a maximum depth of up to 200-250 mm are used.

6.1.26 Priming of the bottom and walls of a contoured pothole═ cleaned of small pieces and dust═ with a thin layer of liquid (hot) or liquefied bitumen or bitumen emulsion (bitumen consumption 0═3-0═5 l/m) can be performed using: ═ asphalt distributor═ road repairer, etc.

Effective for lubricating a repaired pothole are small-sized installations (5 hp) ═ pumping bitumen emulsion into the spray nozzle of a hand-held fishing rod with a hose 3-4 m long, installations supplying emulsion from a barrel with a manual pump.

For small volumes of work and small potholes, priming with emulsion can be carried out from portable containers (10-20 l) with spraying with compressed air according to the principle of a spray gun.

6.1.27 The asphalt mix is ​​laid manually or using small-sized asphalt pavers. When laying the mixture manually, the leveling of the asphalt concrete mixture is carried out with improvised means (rakes and trowels).

The pothole is filled with asphalt concrete mixture in layers of 5-6 cm, taking into account the safety factor for compaction. Of the means of mechanization for compaction, a small-sized skating rink or a vibrating plate is used. The surface of the repaired area after compaction should be at the level of the existing pavement.

6.1.28 To increase the efficiency of repairing potholes with hot asphalt mix, special repair machines are used. A thermal container for hot asphalt mix with thermal insulation and heating is placed on the base machine; tank, pump and sprayer for bitumen emulsion; a compressor for cleaning and dedusting repair cards, a jackhammer drive for cutting the edges of repair cards, a vibrating plate for compacting the asphalt concrete mixture.

6.1.29 When carrying out work in conditions of increased moisture, the potholes are dried with compressed air (hot or cold) before priming.

6.1.30 Repair of potholes by the jet-injection method using a cationic bitumen emulsion is carried out using trailed special equipment. Cleaning the pothole for repair is carried out with a jet of compressed air or by suction, priming - with an emulsion heated to 60-75 ° C, filling - with crushed stone blackened during injection. With this repair method, edge trimming can be omitted (Fig. 6.1).

Figure 6.1 - The sequence of operations for the jet-injection method of filling the pothole: 1 - cleaning the pothole with a high-speed air jet; 2 - coating the surface of the pothole; 3 - filling and sealing; 4 - dry dressing

Figure 6.1 - The sequence of operations for the jet-injection method of filling the pothole: 1 - cleaning the pothole with a high-speed air jet; 2 - coating the surface of the pothole; 3 - filling and sealing; 4 - dry dressing

6.1.31 As a repair material, crushed stone of a fraction of 5-10 mm and an emulsion of the EBK-2 type are used. A concentrated emulsion (60-70%) based on bitumen BND 90/130 or BND 60/90 is used with an approximate consumption of 10% by weight of crushed stone. The surface of the "seal" is sprinkled with white crushed stone with a layer of one crushed stone. The traffic opens in 10-15 minutes. Works are carried out at an air temperature not lower than + 5 ° C, both on dry and wet surfaces.

6.1.32 On roads III-IV categories and in cases of "emergency" repairs for higher categories of roads, the repair of potholes in the asphalt concrete layer on the cement concrete pavement can be carried out using wet organic-mineral mixtures (WOMS). The repair method using FOMS provides for cleaning a pothole, filling it with a mixture of moistened mineral material of a selected composition and a liquid organic binder (tar or liquefied bitumen) and compacting the mixture. The thickness of the laid layer of material must be at least 3 cm.

The composition of VOMS consists of limestone or dolomite crushed stone of a fraction of 5 ... 20 mm (up to 40%) ═ sand with a particle size modulus of at least 1═0═ mineral powder (6 ... 12%)═ binder (tar ═ liquid or liquefied viscous bitumen) in the amount 6…7% and water. Instead of crushed stone, it is allowed to use screenings of crushing═ PGS═ crushed slag. The mixture can be harvested for the future with the preparation in conventional asphalt plants, retrofitted with a system for supplying and dosing water.

VOMS can be used at air temperatures down to -10°C and laid on a damp surface of a pothole.

6.1.33 Another method of "emergency repair" of potholes is the repair using cold asphalt (repair) mixes.

This type of repair is used when the area of ​​the pothole is up to 1 m.

The repair cold mix consists of a mineral filler, an organic binder with the introduction of special additives into it. The mixing of the mixture is carried out in forced action installations.

As an organic binder, bitumen grades BND 60/90 and BND 90/130 are used, which meet the requirements of GOST 33133-2014. The properties of bitumens have been improved by introducing various additives with an organic solvent (thinner).

Thinners used to give the initial bitumen grade MG 130/200 a given viscosity (GOST 11955-82) must meet the requirements of GOST R 52368-2005 and GOST 10585-99. The amount of thinner is 20-40% by weight of the bituminous binder and is specified by the laboratory.

In the process of preparing repair mixtures, surfactants are used to increase the adhesion strength of the binder to the surface of mineral materials and ensure the desired properties.

The temperature of the mixture should not be below -10°C. It is allowed to lay the repair mixture on a frozen and wet base, but in the absence of puddles, ice and snow in the repaired map.

When repairing potholes in the coating, depending on the depth of destruction, the repair mixture is laid in one or two layers with a thickness of not more than 5-6 cm with careful compaction of each layer.

When removing potholes on the coating, observe technological sequence, which includes cleaning the damaged area, leveling and compacting the repair mixture.

It is not necessary to prime the repaired surface with bitumen or bitumen emulsion.

The repair mixture is laid taking into account the reduction in the layer thickness during compaction, for which the thickness of the applied layer should be 25-30% more than the depth of the pothole.

When repairing potholes, depending on the area of ​​the repaired area, the mixture is compacted with a vibrating plate, manual vibrating roller, mechanical, and for small amounts of work - with a manual rammer. With a pothole size exceeding 0.5 m, the mixture is compacted with a vibrating plate. The movement of the sealing means is directed from the edges of the section to the middle. The seal is considered complete if there is no trace of the sealing agent.

The mixture, as a rule, is packed in plastic bags weighing 20, 25, 30 kg or in other quantities as agreed with the consumer. Unpackaged mixture is allowed to be stored under a canopy in open stacks on concrete floor within 1 year. Packed in sealed bags, the mixture retains its properties for two years.

6.1.34 One of the pothole repair methods is to fill them with a poured asphalt concrete mixture. This mixture differs from the usual asphalt concrete mixture by the increased content of mineral powder (20-24%) and bitumen (9-10%) grade BND 40/60. The content of crushed stone is 40-45%. At a laying temperature of 200-220°C, the mixture has a cast consistency, which eliminates the need for compaction. The mixture is delivered to the place of work by special machines with a heated container and a prepared card is filled with it for repairing potholes.

After the mixture cools down to 50-60°C, traffic is opened along the repaired area.

When installing new layers of asphalt concrete pavement, the use of cast asphalt concrete mixtures for repairing potholes is not allowed. When laying new asphalt concrete layers, the poured asphalt repair cards on the underlying layers should be removed.

6.1.35 Separate defects on the surface of the asphalt concrete pavement in the form of chipping and peeling are eliminated by the jet-injection method, similar to the repair of potholes.

6.2 Surface treatment device on pavement

6.2.1 The surface treatment device on the road surface improves its grip properties, as well as protection against wear and weather conditions. With the surface treatment device, the tightness of the coating increases and its service life increases. In addition, minor irregularities and defects are eliminated.

6.2.2 A single surface treatment is carried out on the surface of the asphalt concrete pavement if it has defects in the form of: peeling, chipping, cracks and small potholes.

Double surface treatment is performed if there is a significant amount of destruction on the asphalt concrete pavement (more than 15% of total area coatings). In this case, a decision can be made to mill the top layer of the asphalt concrete pavement.

6.2.3 A single surface treatment device is produced in accordance with the Guidelines for the device of a single rough surface treatment using a technique with synchronous distribution of bitumen and crushed stone.

6.2.4 Single surface treatment is carried out, as a rule, in the summer warm periods of the year, on a dry and sufficiently warm surface at an air temperature of at least +15°C.

The sequence of the single surface treatment device:

Preparatory work;

Single surface treatment device;

Care of the surface treatment layer.

6.2.5 Preparatory work includes:

Elimination of coating defects;

Selection and preparation of crushed stone and bitumen;

Selection of the initial consumption rate of crushed stone and bitumen;

Selection and adjustment of equipment and machines that are part of a specialized detachment;

Education and training of service personnel of machines and mechanisms.

6.2.6 In the areas selected for the single surface treatment device, the elimination of defects on the roadway is carried out in accordance with the requirements. Patching of potholes and cracks must be completed at least 7 days before the start of the surface treatment device.

6.2.7 The choice of the approximate consumption rate of crushed stone and bitumen for a single surface treatment device is carried out according to Table 6.1.

Table 6.1 - Selection of the approximate consumption rate of crushed stone and bitumen for a single surface treatment device

Fraction of crushed stone, mm	Consumption
	crushed stone, m/100 m	bitumen, kg/m

6.2.8 For surface treatment, it is recommended to use machines with synchronous distribution of binder and crushed stone (synchronous distribution of binder and crushed stone, Fig. 6.2).

6.2.9 The surface treatment device is carried out in the following sequence:

Cleaning the surface from dust and dirt;

Clarification of material consumption rates;

Synchronous distribution of bitumen and crushed stone on the surface of the carriageway;

Compaction of the freshly laid rough layer;

Surface care.

6.2.10 Cleaning the surface of the coating from dust and dirt is carried out by specialized machines with nylon, and in case of severe contamination of the surface - with a metal brush and watering equipment. The coating is cleaned in two to five passes along the trail.

Figure 6.2 - Synchronous distribution of binder and crushed stone with a surface treatment device

Figure 6.2 - Synchronous distribution of binder and crushed stone with a surface treatment device

6.2.11 Compaction of the freshly laid layer is carried out immediately after the passage of the machine with synchronous distribution of binder and crushed stone. 5-6 passes of a self-propelled ice rink on pneumatic wheels are carried out along the surface with a wheel load of at least 1.5 tons and a tire pressure of 0.7-0.8 MPa, or a skating rink with rubberized metal rollers. The final formation of the layer occurs under the action of the passing road transport with a speed limit of up to 40 km / h. The period of formation of a freshly laid layer should be at least 10 days.

6.2.12 Maintenance of freshly laid surface treatment includes the following operations:

Speed ​​limit up to 40 km/h;

Regulation of traffic across the entire width of the carriageway with the help of guide fences;

Cleaning of unattached crushed stone with a brush of a watering machine no later than one day after the completion of compaction;

Reconsolidation with a roller.

6.2.13 With a single surface treatment device in a synchronous way, the time interval between bitumen pouring and crushed stone distribution is less than 1 s. This provides a significant improvement in the adhesive quality of the binder, by penetrating it into the micropores of crushed stone. In this case, the crushed stone adheres well to the surface of the coating. With the synchronous distribution of binder and crushed stone, the quality of surface treatment is significantly increased, both when using hot bitumen as a binder and bitumen emulsion.

6.2.14 Work on the double surface treatment device is carried out on a clean, dust-free surface of the coating, dry when using bitumen and moistened when using bitumen emulsions. The air temperature when used as a binder bitumen should not be lower than +15°C, and when using a bitumen emulsion - not lower than +5°C. In some cases, if it is impossible to ensure the required purity of the milled coating, it is recommended to prime it by pouring liquid bitumen at a rate of 0.3-0.5 l/m.

6.2.15 The technological process of the double surface treatment device includes:

Milling of asphalt concrete pavement;

Cleaning the milled coating from dust and asphalt crumb residues;

Priming of the surface of the coating (if necessary);

The first pouring of bituminous binder - 1.0 ... 1.2 l / m and the distribution of processed crushed stone of a fraction of 20 ... 25 mm in the amount of 20 ... 25 kg / m, followed by rolling the layer with two or three passes of a light roller (5 ... 8 tons);

The second bottling of the binder at a rate of 0.8 ... 0.9 l / m;

Distribution of treated crushed stone with a fraction of 10…15 mm (13…17 kg/m) followed by compaction with four or five passes of a light roller.

6.2.16 Estimated costs of binder and crushed stone during their distribution on the coating are given in Table 6.2.

Table 6.2 - Consumption of binder and crushed stone (excluding pre-treatment)

Crushed stone size, mm	Consumption rate
	crushed stone, m/100 m	bitumen, l/m	emulsion, l/m, at bitumen concentration, %
Single surface treatment
Double surface treatment
	First placer	First bottling
	Second placer	Second bottling
Note - When using black crushed stone, the binder consumption rates are reduced by 20-25%.

6.2.17 The decision on pre-treatment of crushed stone with a binder in the installation (blackening of crushed stone) is made based on the results of laboratory studies of the adhesion of crushed stone with a binder in accordance with GOST 12801-98 *. For blackening, it is recommended to use bitumen grades BND 60/90, BND 90/130, BND 130/200, MG 130/200, MG 70/130.

6.2.18 The main filling of the binder is carried out on half of the roadway in one step without gaps and gaps. If it is possible to provide a detour, the binder is poured over the entire width of the carriageway.

6.2.19 The temperature of the bitumen during its distribution should be within the following limits: for viscous bitumen grades BND 60/90, BND 90/130 - 150160°C; for grades BND 130/200 - 100130°С; for polymer-bitumen binders - 140160°C.

6.2.20 For surface treatment using bitumen emulsions, cationic emulsions EBK-1, EBK-2 and anionic emulsions EBA-1, EBA-2 are used. When using a surface treatment device using cationic bitumen emulsions, crushed stone is used that has not been pre-treated with organic binders. When using anionic emulsions - mainly black gravel.

6.2.21 The temperature and concentration of the emulsion are set depending on weather conditions:

At air temperatures below 20°C, the emulsion should have a temperature of 4050°C (with a bitumen concentration in the emulsion of 55-60%). The emulsion is heated to this temperature directly in the asphalt distributor;

At air temperatures above 20°C, the emulsion can not be heated (at a bitumen concentration in the emulsion of 50%).

6.2.22 Immediately after the scattering of crushed stone, it is compacted with smooth-roller rollers weighing 6-8 tons (4-5 passes along one track). Then with heavy smooth-roller rollers weighing 10-12 tons (2-4 passes along one track). For a better manifestation of the rough structure, it is advisable to carry out the final stage of compaction with smooth-roller rollers with rubber-coated rollers.

6.2.23 When using bitumen emulsions, work is carried out in the following sequence:

Wetting the treated coating with water (0.5 l/m);

Pouring the emulsion over the coating in the amount of 30% of the consumption;

Distribution of 70% of crushed stone from the total consumption (gap no more than 20 m with a time interval of no more than 5 minutes from the moment of pouring the emulsion);

Pouring the remaining emulsion;

Distribution of the remaining rubble;

Compaction with rollers weighing 6-8 tons, 3-4 passes along one track (the beginning of compaction should coincide with the beginning of the breakdown of the emulsion);

Surface care.

6.2.24 When using cationic bitumen emulsions, traffic is opened immediately after compaction. Care for double surface treatment is carried out within 10 ... 15 days, by regulating traffic along the width of the carriageway and limiting the speed to 40 km / h.

In the case of using an anionic emulsion, the movement should be opened no earlier than one day after the surface treatment device.

6.3 Installation of thin friction wear-resistant protective layers on the pavement surface

6.3.1 The device of thin protective layers of cast emulsion-mineral mixtures

6.3.1.1 Thin cast mineral-emulsion mixture (LEMS) friction wear layers are used as friction and waterproofing wear layers to increase service life. pavement and improving driving conditions. Wear layers are primarily needed to restore the performance of coatings.

6.3.1.2 When repairing asphalt concrete layers laid on a cement concrete pavement, the following options for using cast emulsion-mineral mixtures are possible:

1) laying LEMS on upper layer asphalt concrete pavement;

2) laying LEMS on the milled asphalt concrete pavement.

6.3.1.3 Before laying a layer of LEMS, the coating is primed with an emulsion or bitumen grades BND 200/300 at the rate of 0.3-0.4 l/m (in terms of bitumen).

6.3.1.4 Preparation and laying of LEMS is carried out with special single-pass machines that mix materials and distribute the mixture over the surface of the coating.

It is recommended to use crushed stone of various fractions up to 15 mm from stone of igneous and metamorphic rocks with a strength of at least 1200. Sand fraction 0.1 (0.071) -5 mm consists of crushed sand or a mixture of natural and crushed sand in equal proportions. For a mineral powder (preferably activated) from carbonate rocks, it is assumed that the total amount of particles finer than 0.071 mm contained in the mixture is 5-15%. The binder is used in the form of cationic bitumen emulsions of the EBK-2 and EBK-3 class, containing 50-55% bitumen. The compositions of LEMS are given in Table 6.3.

Table 6.3 - Compositions of cast emulsion-mineral mixtures

Mix type	Number of components, % by weight
	granite crushed stone, mm				mine- ral- ny pore- shock	portland- cement	water for pre- body wetting	bitumen emulsion (in terms of bitumen)
			crushed- ny	nature- ny
rubble
Sandy
			[email protected], we'll figure it out.

Low price for asphalting roads!
from 400 rubles per sq. meter

Asphalt patching

Pothole restoration of the road allows you to carry out repairs with a minimum expenditure of resources. Pothole repair is used if the damage to the asphalt pavement is less than 15%, and the diameter of the pits does not exceed 25 square meters. The depth of filling the pit with asphalt emulsion is 5 cm and is sufficient for Moscow roads.

The cost of road repairs in Moscow from 570 rubles.

For road repair, the price is calculated during the marking process. The selection of pits and the calculation of the dimensions of rectangular cards for dismantling and patching allow you to accurately know the quadrature and announce the price.

The cost of patching the asphalt concrete pavement is 570 rubles. per m2. In this case, all consumables are included in the price, the layer thickness is 5 cm.

You can also order a free visit of a specialist to the object for advice on the repair and construction of the road. The price of patching asphalt is fixed, and depends solely on the scale of the work.

Pothole restoration saves money by partially replacing damaged areas. Experience, equipment and own production of secondary materials allow Undorstroy LLC to install one of the most favorable prices in Moscow and the region for road repairs.

our clients

We have been cooperating with Moscow urban planning and regional transport authorities for 15 years. Our company is chosen due to quality assurance and good advice from 10 Moscow districts.

Our clients have already become:

• councils of districts and prefectures of Moscow;
• municipal authorities of the Tula region;
• state organizations HOA;
• private transport companies.

The management of all the listed structures responded positively about our company, remaining completely satisfied with the work of Undorstroy LLC.

Asphalt patching schedule

One of the advantages of patching is the ability to quickly restore coverage. For repairs, it is not required to adjust large-sized equipment and block traffic. The amount of work during the restoration is minimal and consists of only three main stages - preparation, dismantling and asphalting.

In order to restore the road surface as quickly as possible, the Undorstroy company works:

• around the clock;
• no days off;
• on holidays.

Carrying out patching of roads in Moscow and the region in most cases does not require blocking the route. We level the surface alternately on different lanes. Partial overlap allows you not to create obstacles to the movement of vehicles for the duration of the work.

The only restriction is the condition that road repairs are carried out only in positive temperatures and dry weather. Otherwise, it is impossible to guarantee the durability of patches and high performance.

Why is it worth ordering road repairs in Undorstroy?

You can order the services of the Undorstroy company by contacting us by phone and arranging a meeting with a consultant, or by leaving a request on the website. At our disposal:

• professional staff;
• any road special equipment;
• necessary materials;
• significant experience.

All our employees are regularly certified for the ability to perform road repair work. Our fleet has its own equipment of any size, from plate compactors and cochers to asphalt pavers and 10-ton rollers.

Undorstroy independently produces secondary crushed stone and recycles asphalt in order to reduce the price for customers. We started work in 2001, and maintain a reputation as a reliable partner for the construction and repair of roads in Moscow.

Asphalt patching technology

After agreement with the customer, we send the necessary equipment and certified specialists to the place of pavement repair. Upon arrival at the site for patching in Moscow, our specialists block one of the traffic lanes.

After installing fences, signs and organizing detours, skilled workers immediately begin to repair the road. Elimination of holes includes several stages:

1. Marking
2. sawing out cards
3. Dismantling of the coating
4. Base cleaning
5. Asphalting
6. Territory cleaning

Marking is applied to determine the scope of work, calculate the cost and mark damaged areas. A cold asphalt cutter runs along the finished marking, cutting even rectangular patch cards around the pit.

Cutting is necessary because microcracks in the web cover a larger area than visible damage. The contour of the dismantling card is usually 20 cm wider than the excavation area. Cutting with a milling cutter does not exceed the width of the lane even with large cracks, so as not to create obstacles to movement.

After passing the contours of the rectangle for the patch, the notch is cleared of the resulting crumb, usually by hand, using a jackhammer in the center of the card. The company "Undorstroy" free of charge takes out and accepts an asphalt chip from the object. With us, you can reduce the cost of road repair during dismantling.

Cleared of chips, dust and debris, a rectangular recess is prepared by the Undorstroy company, to create a carrier layer, with secondary crushed stone own production. Additionally, it is possible to treat with a hot bitumen emulsion to strengthen the base and form an interlayer.

The prepared area is covered with asphalt by road workers of the required qualification. The filling of the patch is carried out hand shovels, from special equipment - cochers, which do not allow the finished asphalt to harden.

An asphalt roller can pass behind the workers. With small amounts of work, road builders use mobile vibrating plates for local patching of the road surface.

compacted asphalt pavement does not require waiting for curing. After completion of work, construction equipment, debris are removed, fences are removed. The traffic flow along the lane can be restored, and the workers move on to the next part or hand over the facility to the customer.

GOST R 54401-2011

Group G18

NATIONAL STANDARD OF THE RUSSIAN FEDERATION

Automobile roads common use

ASPHALT CONCRETE ROAD CAST HOT

Technical requirements

Automobile roads of general use. Hot road mastic asphalt. technical requirements

OKS 93.080.20
OKP 57 1841

Introduction date 2012-05-01

Foreword

Goals and principles of standardization in Russian Federation established by the Federal Law of December 27, 2002 N 184-FZ "On Technical Regulation", and the rules for the application of national standards of the Russian Federation - GOST R 1.0-2004 "Standardization in the Russian Federation. Basic provisions"

About the standard

1 DEVELOPED by the Autonomous Non-Commercial Organization "Research Institute of the Transport and Construction Complex" (ANO "NII TSK") and the Open Joint Stock Company "Asphalt Concrete Plant No. 1", St. Petersburg (JSC "ABZ-1", St. Petersburg)

2 INTRODUCED by the Technical Committee for Standardization TC 418 "Road Facilities"

3 APPROVED AND PUT INTO EFFECT by Order of the Federal Agency for Technical Regulation and Metrology dated September 14, 2011 N 297-st

4 This standard has been developed taking into account the main regulatory provisions of the European regional standard EN 13108-6:2006 * "Bituminous mixtures - Material specifications - Part 6: Cast asphalt" (EN 13108-6:2006 "Bituminous mixtures - Material specifications - Part 6 : Mastic Asphalt", NEQ)
________________
* Access to international and foreign documents mentioned hereinafter in the text can be obtained by clicking on the link. - Database manufacturer's note.

5 INTRODUCED FOR THE FIRST TIME


Information about changes to this standard is published in the annually published information index "National Standards", and the text of changes and amendments - in the monthly published information indexes "National Standards". In case of revision (replacement) or cancellation of this standard, a corresponding notice will be published in the monthly published information index "National Standards". Relevant information, notification and texts are also posted in the public information system - on the official website of the Federal Agency for Technical Regulation and Metrology on the Internet

1 area of ​​use

1 area of ​​use

This standard applies to hot cast asphalt concrete and hot cast asphalt road mixes (hereinafter referred to as cast mixes) used for pavement on public roads, bridge structures, tunnels, as well as for patching, and establishes technical requirements for them. .

2 Normative references

This standard uses normative references to the following standards:

GOST R 52056-2003 Polymer-bitumen road binders based on styrene-butadiene-styrene block copolymers. Specifications

GOST R 52128-2003 Bituminous road emulsions. Specifications

GOST R 52129-2003 Mineral powder for asphalt concrete and organo-mineral mixtures. Specifications

GOST R 54400-2011 Public automobile roads. Asphalt road cast hot. Test Methods

GOST 12.1.004-91 Occupational safety standards system. Fire safety. General requirements

GOST 12.1.005-88 System of labor safety standards. General sanitary and hygienic requirements for the air of the working area

GOST 12.1.007-76 Occupational safety standards system. Harmful substances. Classification and General requirements to security

GOST 12.3.002-75 Occupational safety standards system. Manufacturing processes. General safety requirements

GOST 17.2.3.02-78 Nature protection. Atmosphere. Rules for establishing allowable emissions harmful substances industrial enterprises

GOST 8267-93 Crushed stone and gravel from dense rocks for construction works. Specifications

GOST 8269.0-97 Crushed stone and gravel from dense rocks and industrial waste for construction work. Methods of physical and mechanical tests

GOST 8735-88 Sand for construction work. Test Methods

GOST 8736-93 Sand for construction work. Specifications

GOST 22245-90 Viscous oil road bitumen. Specifications

GOST 30108-94 Building materials and products. Determination of specific effective activity of natural radionuclides

GOST 31015-2002 Asphalt concrete mixes and crushed stone-mastic asphalt concrete. Specifications

Note - When using this standard, it is advisable to check the validity of reference standards in the public information system - on the official website of the Federal Agency for Technical Regulation and Metrology on the Internet or according to the annually published information index "National Standards", which was published as of January 1 of the current year , and according to the corresponding monthly published information signs published in the current year. If the reference standard is replaced (modified), then when using this standard, you should be guided by the replacing (modified) standard. If the referenced standard is canceled without replacement, the provision in which the reference to it is given applies to the extent that this reference is not affected.

3 Terms and definitions

In this standard, the following terms are used with their respective definitions.

3.1 asphalt road cast hot: Asphalt-concrete road cast hot mix frozen in the process of cooling and formed in the coating

3.2 asphalt granulate: Material resulting from milling an existing asphalt pavement (recycled asphalt)

3.3 leveling layer: A layer of variable thickness that is applied to an existing layer or surface in order to create the desired surface profile for the next structural layer of uniform thickness

3.4 astringent (astringent): Organic compound (viscous road bitumen, modified bitumen) designed to connect the grains of the mineral part of the cast mixture

3.5 dephlegmator: Special additives based on natural waxes and synthetic paraffins with a melting point from 70 °C to 140 °C, used to modify petroleum binders in order to reduce their viscosity

3.6 additive: An ingredient that can be added to a mixture in specified amounts to affect the properties or color of the mixture

3.7 road surface: Structure consisting of one or more layers, perceiving the loads from the transport and ensuring its unhindered movement

3.8 given composition of the mixture (composition of the mixture): Optimally selected composition of a certain asphalt concrete mixture, indicating the particle size distribution curve of the mineral part of the mixture and the percentage of components

3.9 acidic rocks: Igneous rocks containing more than 65% silicon oxide (SiO

3.10 kocher (mobile kocher): Special mobile thermos boiler for cast mixture transportation, equipped with heating, mixing system (with or without independent drive) and devices to ensure cast mixture temperature control

3.11 hot flush method: The technological process of creating a rough surface of the top layer of the road surface by applying a grain mineral mixture (fractionated sand or crushed stone) or blackened crushed stone to a cast mixture that has not cooled down after laying

3.12 modified bitumen: Binder made on the basis of viscous road bitumen by introducing polymers (with or without plasticizers) or other substances in order to impart certain properties to bitumen

3.13 bridge building: Road engineering structure (bridge, overpass, viaduct, flyover, aqueduct, etc.), consisting of one or more span structures and supports, laying a transport or pedestrian path over obstacles in the form of watercourses, reservoirs, canals, mountain gorges, city streets , railways and roads, pipelines and communications for various purposes

3.14 main rocks: Igneous rocks containing 44% to 52% silicon oxide (SiO

3.15 coating surface: The top layer of the road surface that comes into contact with traffic

3.16 polymer-bitumen binder (PBV): Polymer modified viscous road bitumen

3.17 full passage of mineral material: The amount of material whose grain size is smaller than the size of the holes of this sieve (the amount of material that passes when sieving through this sieve)

3.18 total balance of mineral material: The amount of material whose grain size is larger than the size of the holes of this sieve (the amount of material that did not pass when sifting through this sieve)

3.19 row (laying strip): Pavement element laid in one working shift or working day

3.20 segregation (stratification): Local change in the granulometric composition of the mineral materials of the cast mixture and the content of the binder in the initially homogeneous mixture, due to individual movements of particles of coarse and fine fractions of the mineral part, during the storage of the mixture or its transportation

3.21 layer (structural layer): A building element of a road surface, consisting of a material of one composition. The layer can be laid in one or more rows

3.22 asphalt road cast hot mix: Castable mixture, with minimum residual porosity, consisting of a grain mineral part (crushed stone, sand and mineral powder) and viscous petroleum bitumen (with or without polymeric or other additives) as a binder, which is laid by injection molding technology, without compaction , at a mixture temperature of at least 190 °C

3.23 medium rocks: Igneous rocks containing 52% to 65% silicon oxide (SiO

3.24 stationary kocher: A special stationary storage hopper for homogenization and storage of the cast mixture after the end of its production process, equipped with heating, a mixing system, a loading device and temperature control devices for the cast mixture

3.25 workability: Qualitative characteristic of a cast mixture, determined by the efforts that ensure its homogenization during mixing, its suitability for transportation and laying. Includes such properties of the cast mixture as flowability, suitability for laying by injection technology, spreading rate over the surface

3.26 blackened gravel: Graded crushed stone treated with bitumen, in an unbound state and intended to create a surface rough layer.

4 Classification

4.1 Cast mixtures and asphalt concretes based on them, depending on the largest grain size of the mineral part, the content of crushed stone in them and the purpose, are divided into three types (see table 1).


Table 1

The main classification features of cast mixtures				Purpose
	Maximum grain size of the mineral part, mm
				New construction, overhaul and patching
				New construction, overhaul and patching, sidewalks
				Sidewalks, bike paths

5 Technical requirements

5.1 Cast mixtures must be prepared in accordance with the requirements of this standard according to the technological regulations approved in the prescribed manner by the manufacturer.

5.2 Grain compositions of the mineral part of mixtures of cast and asphalt concretes based on them, when using round sieves, must correspond to the values ​​\u200b\u200bspecified in table 2.


table 2

Mix type	Grain size, mm, finer*
* Total passages of mineral material, in percent by weight.

Grain compositions of the mineral part of mixtures of cast and asphalt concretes based on them, using square sieves, are given in Appendix B.

Graphs of permitted granulometric compositions of the mineral part of the cast mixture are given in Appendix B.

5.4 Indicators of the physical and mechanical properties of mixtures of cast and asphalt concrete based on them, the temperature of production, storage and laying should correspond to those indicated in Table 3.


Table 3

Name of indicator	Norms for types of mixtures
1 Porosity of the mineral core, % by volume, not more than			Not standardized
2 Residual porosity, % by volume, no more			Not standardized
3 Water saturation, % by volume, no more
4 Mixture temperature during production, transportation, storage and laying, °С, not higher	215* 230**	215* 230**	215* 230**
5 Tensile strength at a split at a temperature of 0 °C, MPa (optional):			Not standardized
no more
* Values ​​correspond to the maximum temperature of the mixture from the condition of using polymer-bitumen binders. ** The values ​​correspond to the maximum temperature of the mixture from the condition of using road oil viscous bitumen.

The physical and mechanical properties of mixtures of cast and asphalt concrete based on them are determined in accordance with GOST R 54400.

5.5 The maximum temperature shown in Table 3 is valid for any location in the mixer and storage and transport containers.

5.6 The values ​​of the index of the depth of indentation of the stamp, depending on the purpose and place of application of mixtures of cast and asphalt concrete based on them, are shown in Table 4.


Table 4

Application area	Type of work	Die indentation range for mix types, mm
1 Public automobile roads with a traffic intensity of 3000 vehicles/day; bridge structures, tunnels.		1.0 to 3.5 Increase after 30 min Not more than 0.4 mm		Not applicable
		1.0 to 4.5 Increase after 30 min Not more than 0.6 mm
2 Public automobile roads with an intensity of 3000 vehicles / day	The device of the top layer of the coating	1.0 to 4.0 Increase after 30 min Not more than 0.5 mm		Not applicable
	The device of the bottom layer of the coating	1.0 to 5.0 Increase after 30 min Not more than 0.6 mm
3 Pedestrian and bicycle paths, crossings and sidewalks	The device of the upper and lower layers of the coating	Not applicable	from 2.0 to 8.0*	from 2.0 to 8.0*
4 All types of roads, as well as bridges and tunnels	Pothole repair of the top layer of the coating; leveling layer device	1.0 to 6.0 Increase after 30 min Not more than 0.8 mm		Not applicable
* An increase in the stamp indentation rate over the next 30 minutes is not standardized.

The index of the indentation depth of the stamp at a temperature of 40 °C during the first 30 minutes of the test and (if necessary) the increase in the index of the indentation depth of the stamp during the next 30 minutes of the test is determined in accordance with GOST R*.

_______________
* The text of the document corresponds to the original. - Database manufacturer's note.

5.7 Cast mixtures must be homogeneous. The homogeneity of cast mixtures is evaluated in accordance with GOST R 54400 by the coefficient of variation of the values ​​of the index of the indentation depth of the die at a temperature of 40 °C during the first 30 minutes of the test. The coefficient of variation for mixtures of cast types I and II shall not exceed 0.20. This indicator for a mixture of cast type III is not standardized. The index of homogeneity of the cast mixture is determined at intervals not less than monthly. The index of uniformity of the cast mixture is recommended to be determined for each manufactured composition.

5.8 Material requirements

5.8.1 For the preparation of cast mixtures, crushed stone is used, obtained by crushing dense rocks. Crushed stone from dense rocks, which is part of cast mixtures, must comply with the requirements of GOST 8267.

For the preparation of cast mixtures, crushed stone of fractions from 5 to 10 mm is used; over 10 to 15 mm; over 10 to 20 mm; over 15 to 20 mm, as well as mixtures of these fractions. There should be no foreign contaminants in the crushed stone.

The physical and mechanical properties of crushed stone must comply with the requirements specified in Table 5.


Table 5

Name of indicator	Indicator values	Test method
1 Grade by crushability, not less than
2 Abrasion grade, not less than
3 Grade for frost resistance, not lower
4 Weighted average content of lamellar (flaky) and needle-shaped grains in a mixture of crushed stone fractions, % by weight, not more than
7 Specific effective activity of natural radionuclides, Bq/kg:

5.8.2 For the preparation of cast mixtures, sand from crushing screenings, natural sand, and their mixture are used. Sand must comply with the requirements of GOST 8736. In the production of cast mixtures for the top layers of road and bridge structures, sand from crushing screenings or its mixture with natural sand containing no more than 50% natural sand should be used. The grain composition of natural sand in size should correspond to sand not lower than the fine group.

The physical and mechanical properties of the sand must comply with the requirements specified in Table 6.


Table 6

Name of indicator	Indicator values	Test method
1 Grade of strength of sand from screenings of crushing (initial rock), not lower than
4 Specific effective activity of natural radionuclides, , Bq/kg:
For road construction within settlements;
For road construction outside built-up areas

5.8.3 For the preparation of cast mixtures, non-activated and activated mineral powder is used that meets the requirements of GOST R 52129.

The permissible content of powder from sedimentary (carbonate) rocks from the total mass of mineral powder must be at least 60%.

It is allowed to use technical dust from the removal of basic and medium rocks from the dust collection system of mixing plants in an amount of up to 40% of the total mass of the mineral powder. The use of dust from the entrainment of acidic rocks is allowed provided that it is contained in the total mass of the mineral powder in an amount not exceeding 20%. The values ​​of the indicators of fly-away dust must comply with the requirements of GOST R 52129 for MP-2 grade powder.

5.8.4 For the preparation of cast mixtures, viscous oil road bitumen grades BND 40/60, BND 60/90 according to GOST 22245, as well as modified and other bituminous binders with improved properties, are used as a binder according to regulatory and technical documentation agreed and approved by the customer in in accordance with the established procedure, subject to ensuring the quality indicators of cast asphalt concrete from these mixtures at a level not lower than those established by this standard.

5.8.5 When using cast asphalt concrete on bridge structures, in the upper and lower layers of road surfaces with high traffic intensity and design axle loads, polymer-modified bitumen should be used. In these cases, preference should be given to polymer-bitumen binders based on block copolymers such as styrene-butadiene-styrene grades PBB 40 and PBB 60 according to GOST R 52056.

5.8.6 When designing compositions of cast mixtures, the type of binder should be assigned taking into account the climatic features of the construction area, the purpose and place of application of the structural layer, the required (designed) deformation properties of mixtures of cast and asphalt concrete based on them. The suitability of the binder to achieve the required functional characteristics mixtures of cast and asphalt concrete based on them are confirmed in the process of mandatory and optional tests specified in GOST R 54400.

5.8.7 In the production of cast mixtures, it is permissible to use binders modified by introducing dephlegmators into their composition, which make it possible to reduce the temperatures of production, storage and laying of cast mixtures by 10 °C to 30 °C without compromising their workability. The introduction of reflux condensers is carried out in bitumen (polymer-bitumen binder) or in a cast mixture during its production at an asphalt mixing plant.

5.8.8 The specified composition of the cast mixture must be ensured during its production at the asphalt mixing plant. It is forbidden to change the composition of the cast mixture after the completion of its production process by introducing a binder, petroleum products, plasticizers, resins, mineral materials and other substances into the mobile coher in order to change the viscosity of the cast mixture and the physical and mechanical characteristics of cast asphalt concrete.

5.8.9 It is allowed to use recycled asphalt concrete (granulated asphalt) as a filler in a cast mixture. At the same time, its content should not exceed 10% of the mass fraction of the composition of the cast mixture for the device of the lower or upper layers of the road surface and patching and 20% of the mass fraction of the composition of the mixture of cast for the device of the leveling layer. At the request of the consumer, the permissible percentage of asphalt granulate content in the cast mixture can be reduced. The maximum grain size of the crushed stone contained in the asphalt granulate should not exceed the maximum grain size of the crushed stone in the cast mixture. When designing the compositions of cast mixtures with the use of asphalt granulate, the mass fraction of the content and properties of the binder in the composition of this aggregate should be taken into account.

6 Safety and environmental requirements

6.1 When preparing and laying cast mixtures, general safety requirements in accordance with GOST 12.3.002 and fire safety requirements in accordance with GOST 12.1.004 must be observed.

6.2 Materials for the preparation of cast mixtures (crushed stone, sand, mineral powder and bitumen) must correspond to a hazard class not higher than IV in accordance with GOST 12.1.007, referring to the nature of harmfulness and the degree of impact on the human body as low-hazard substances.

6.3 The norms of maximum permissible emissions of pollutants into the atmosphere during the production of works should not exceed the values ​​established by GOST 17.2.3.02.

6.4 Air in working area when preparing and laying cast mixtures, it must meet the requirements of GOST 12.1.005.

6.5 Specific effective activity of natural radionuclides in mixtures of cast and cast asphalt concrete should not exceed the values ​​established by GOST 30108.

7 Acceptance rules

7.1 Acceptance of cast mixtures is carried out in batches.

7.2 A batch is considered to be any amount of a cast mixture of the same type and composition, produced at the enterprise at the same mixing plant during one shift, using raw materials from one delivery.

7.3 To assess the compliance of cast mixtures with the requirements of this standard, acceptance and operational quality control is carried out.

7.4 Acceptance control of the cast mixture is carried out for each batch. During acceptance tests, water saturation, the depth of indentation of the stamp and the composition of the cast mixture are determined. Indicators of the porosity of the mineral core and residual porosity and the indicator of the specific effective activity of natural radionuclides are determined when selecting the compositions of the cast mixture, as well as when changing the composition and properties of the starting materials.

7.5 During the operational quality control of cast mixtures in production, the temperature of the cast mixture in each shipped vehicle is determined, which must not be lower than 190 °C.

7.6 For each batch of shipped cast mixture, the consumer is issued a quality document containing the following product information:

- name of the manufacturer and his address;

- number and date of issue of the document;

- name and address of the consumer;

- order number (batch) and quantity (mass) of cast mixture;

- type of cast mixture (composition number according to the manufacturer's nomenclature);

- temperature of the mixture cast during shipment;

- the brand of binder used and the designation of the standard according to which it was produced;

- the designation of this standard;

- information about the introduced additives and asphalt granulate.

At the request of the consumer, the manufacturer is obliged to provide the consumer with complete information about the released batch of products, including the data of acceptance tests and tests carried out during the selection of the composition, according to the following indicators:

- water saturation;

- depth of indentation of the stamp (including an increase in the index after 30 minutes);

- porosity of the mineral part;

- residual porosity;

- homogeneity of the cast mixture (according to the results of tests of the previous period);

- specific effective activity of natural radionuclides;

- granulometric composition of the mineral part.

7.7 The consumer has the right to conduct a control check of the compliance of the supplied cast mixture with the requirements of this standard, observing the methods of sampling, sample preparation and testing specified in GOST R 54400.

8 Test methods

8.1 The porosity of the mineral core, residual porosity, water saturation, the depth of indentation of the stamp, the composition of the cast mixture, the tensile strength during splitting of cast asphalt concrete are determined according to GOST R 54400.

If square sieves are used in the selection of grain compositions, a set of sieves must be used in accordance with Appendix B to determine the grain composition of the cast mixture.

8.2 Preparation of samples from mixtures of cast and asphalt concrete based on them for testing is carried out in accordance with GOST R 54400.

8.3 The temperature of the cast mixture is determined by a thermometer with a measurement limit of 300 °C and an error of ±1 °C.

8.4 The specific effective activity of natural radionuclides is taken from its maximum value in the mineral materials used. This data is indicated in the quality document by the supplier enterprise.

In the absence of data on the content of natural radionuclides, the manufacturer of the cast mixture carries out input control of materials in accordance with GOST 30108.

9 Transport and storage

9.1 Prepared cast mixtures must be transported to the place of laying in cochers. It is not allowed to transport the cast mixture in dump trucks or other vehicles in the absence of installed and functioning systems for its mixing and maintaining the temperature.

9.2 The maximum temperature of the cast mixture during storage must comply with the values ​​specified in Table 3 or the requirements of technological regulations for this type of work.

9.3 Mandatory conditions for the transportation of cast mixtures to the place of laying:

- forced mixing;

- exclusion of segregation (stratification) of the cast mixture;

- protection from cooling, precipitation.

9.4 In the case of long-term transportation or storage of the cast mixture in stationary cochers at asphalt mixing plants, its temperature should be reduced for the period of the expected storage time. When storing a mixture of cast from 5 to 12 hours, their temperature should be lowered to 200 ° C (when using polymer-bitumen binders) or up to 215 ° C (when using viscous oil bitumen). After the end of the storage period, immediately before the production of laying work, the temperature of the cast mixture is increased to the permissible values ​​\u200b\u200bspecified in Table 3 or in the technological regulations for this type of work.

9.5 The time elapsed from the production of a cast mix at an asphalt mixing plant to its complete unloading from a mobile coher when laying in a pavement should not exceed 12 hours.

9.6 Cast mixture is subject to disposal as construction waste under the following conditions:

- exceeding the maximum allowable shelf life of the cast mixture;

- unsatisfactory workability of the mixture, loss of the ability to be a pourable mixture and the ability to spread over the base, friability (incoherence), the presence of brown smoke emanating from the cast mixture.

9.7 Instrumentation that monitors the temperature of the cast mixture at the asphalt mixing plant and in the Kocher (stationary and mobile) must be calibrated (verified) at least once every three months.

10 Instructions for use

10.1 The installation of coatings from a mixture of cast is carried out in accordance with the technological regulations approved in the prescribed manner.

10.2 The cast mixture must be placed in the coating only in a liquid or viscous-fluid state that does not require compaction.

10.3 Laying cast mixtures should be carried out at a temperature of the ambient air and the underlying structural layer of at least 5 °C. It is allowed to use cast mixtures at an ambient temperature of up to minus 10 °C for the performance of works to remove an emergency situation on the carriageway of roads with asphalt concrete pavements. In these cases, measures should be taken to ensure sufficient quality of adhesion of cast asphalt concrete with the underlying structural layer.

10.4 Cast mixtures for paving, sidewalks and patching should be unloaded directly onto the surface of the underlying structural layer or waterproofing layer. The surface of the underlying layer must be dry, clean, dust-free and must meet the requirements for asphalt concrete and monolithic cement concrete bases and coatings.

When laying the mixture cast on concrete base or asphalt concrete pavement prepared by cold milling, such surfaces should be pre-treated with a bitumen emulsion according to GOST R 52128 with a flow rate of 0.2-0.4 l / m in order to ensure proper adhesion of the layers. Accumulation of the emulsion in low areas of the base surface is not allowed. It is obligatory to require complete disintegration of the emulsion and evaporation of the resulting moisture prior to laying the cast mixture. The use of bitumen instead of bitumen emulsion for surface treatment is not allowed.

Emulsion treatment of the underlying layer of poured asphalt concrete is not carried out when the lower and upper layers of the pavement are made of poured asphalt concrete.

The emulsion treatment of the underlying layer of cast asphalt concrete is allowed not to be carried out when the upper layer is made of crushed stone-mastic asphalt concrete mixture according to GOST 31015 with a time interval between the layers of no more than 10 days, and also in the absence of traffic in this period along the underlying layer.

10.5 The value of the maximum allowable longitudinal and transverse slopes of the road structure, when using a cast mixture, is from 4% to 6%, depending on the characteristics of the specified composition of the cast mixture and its viscosity.

10.6 Cast mixes of all types may be laid both mechanically using a special device for leveling the cast mix (finisher) and manually. The required workability of cast mixtures is achieved by the manufacturer by adjusting the specified composition and selection of bituminous binder, the introduction of reflux condensers in the production process of the cast mixture, provided that the asphalt concrete remains cast strength characteristics specified in 5.4. The workability can be adjusted by changing the temperature regime of the cast mixture during its laying, taking into account the requirements for the minimum and maximum allowable temperatures of the cast mixture. A mixture intended for mechanized laying may have an increased viscosity and a slower spreading rate on the surface when unloading.

10.7 The final stage of the paving with the top layer of poured asphalt concrete is the device of a rough surface, carried out by the "hot" method of embedding in accordance with the technological regulations approved in the prescribed manner.

10.8 The physical and mechanical properties of the crushed stone used for the device of the rough surface of the top layer of the coating of asphalt concrete poured by the method of embedding "hot" must comply with the requirements given in Appendix A.

Appendix A (recommended). Physical and mechanical characteristics of crushed stone used for the device of the rough surface of the upper layers of the pavement of road cast hot asphalt concrete by the "hot" method of embedding

For the device of the rough surface of the upper layers of the pavement of hot cast asphalt concrete by the method of embedding "hot", fractionated crushed stone of igneous rocks of fractions from 5 to 10 mm, more than 10 to 15 mm and a mixture of fractions from 5 to 20 mm according to GOST 8267 with a consumption of 10 -15 kg/m.

When arranging the lower layers of coatings from cast mixtures, in order to additionally ensure adhesion to the upper layers of coatings from all types of compacted asphalt concrete, crushed stone of igneous rocks of fractions from 5 to 10 mm is distributed "hot" with a flow rate of 2-4 kg / m. It is allowed not to sprinkle the lower layer with crushed stone when installing two-layer pavements of cast asphalt concrete, provided that there is no movement along the lower pavement layer.

To ensure proper adhesion of surface-treated crushed stone with cast asphalt concrete, it is recommended to use crushed stone treated with bitumen (blackened crushed stone). The content of bitumen should be selected so as to exclude its runoff, sticking of crushed stone or uneven coating of the surface of crushed stone with bitumen.

The physical and mechanical properties of the crushed stone used for the device of the rough surface of the upper layers of the poured asphalt concrete pavement by the embedding method must comply with the requirements presented in Table A.1.


Table A.1

Index nameAbrasion mark rock, not less
Frost resistance grade, not lower
Weighted average content of lamellar (flaky) and needle-shaped grains in a mixture of crushed stone fractions, % by weight, not more than
For road construction within settlements;	No more than 740
For road construction outside built-up areas	No more than 1350

The recommended temperature range of the cast mixture at the beginning of the process of distribution of grain mineral materials over its surface is from 140 °C to 180 °C and must be specified in the process of work.

For rough surface walking paths, sidewalks and bicycle paths, natural fractionated sand is used at a rate of 2-3 kg/m.

The recommended grain composition of natural sand is determined by the total residues on the control sieves shown in Table A.2.


Table A.2

	Size of control sieves, mm
Total residues, % by weight

It is acceptable to use crushed graded sand with a grain size of 2.5 to 5.0 mm and a consumption of 4-8 kg/m.

Appendix B (recommended). Complete passages of mineral material using square sieves

B.1 Total passages of mineral material when using square sieves as a percentage by weight are shown in Table B.1.


Table B.1

Types of mixtures	Grain size, mm, finer
											0,063 (0,075)

Mix type

Annex B (recommended). Requirements for the granulometric composition of the mineral part of all types of mixtures

The permitted values ​​of the composition of the mineral part for all types of mixture are in the zone between the two broken lines shown in the graphs of Figures B.1-B.6.

Figure B.1 - Grain composition of mixture type I (round sieves)

Figure B.2 - Grain composition of mixture type I (square sieves)

Figure B.3 - Grain composition of type II mixture (round sieves)

Figure B.4 - Grain composition of type II mixture (square sieves)

Figure B.5 - Grain composition of type III mixture (round sieves)

Figure B.6 - Grain composition of type III mix (square sieves)

Bibliography

Electronic text of the document
prepared by CJSC "Kodeks" and checked against:
official publication
M.: Standartinform, 2012

gravel and gravel coverings. During their repair, periodic repair profiling is carried out, potholes, ruts and subsidence are eliminated, and dust removal measures are also taken. Repair profiling of the coating with the addition of new material is carried out by motor graders or graders at optimal moisture content (from 10 to 15%, depending on the composition of sandy-clay fractions), corresponding to such a state of gravel or crushed stone material, when it is well cut, moved and compacted (Table 12.4 .one).

Table 12.4.1

Repair profiling of gravel (crushed stone) pavements with the addition of new material (per 1000 m of pavement)

Type of work	Coverage width, m	Number of circular passes	The composition of the link	Labor intensity, man-hour
Scarifying the pavement with a scarifier mounted on a motor grader			Machinist of the 5th category - 1	0,59 0,63
		Road worker of the 2nd category - 1
Motor grader moving additional gravel material from the shoulder, leveling across the entire width of the pavement			Machinist of the 5th category - 1	0,77
			0,66
Motor grader mixing of boiled and newly added material with collection in a measuring shaft			Machinist of the 5th category - 1	0,51
			0,44
Leveling and leveling of the material over the entire width of the coating			Machinist of the 5th category - 1	0,77
			0,66
Watering the planned gravel material with water (norm up to 0.9 m 3 per 100 m 2)	6-7	-	Machinist of the 4th category - 1	0,75
Compaction of the material with a self-propelled roller (8-10 tons) in 4 passes on one track	6-7	-	Machinist of the 5th category - 1	2,2
Regulation of movement along the width of the pavement and maintenance of that pavement within 3 days with rearrangement of fences	6-7	-	Road worker of the 2nd category -1	1,38

To be repaired boil up. After removing the boiled material, the pothole is covered with gravel material, in composition close to the material of the upper layer of the coating with grains no larger than 20 mm, 1 ... 2 cm above the coating level. Scoured material can be used to seal potholes, but only after it has been screened.

With a large amount of work, gravel material is compacted with self-propelled rollers on pneumatic tires or rollers weighing 5 ... 10 tons, and with a small amount of pneumatic, electric or manual rammers weighing 25 ... 30 kg. Seal from the edges to the middle of the potholes. For better compaction, the material is watered with water at the rate of 1.5 ... 2 l / m 2 for each centimeter of the depth of the pothole. Instead of water, it is advisable to use a 30% aqueous solution of calcium chloride CaCl 2 or a 30-40% aqueous solution of technical lignosulfonate.

Repair of potholes or subsidence of crushed stone pavement built by the wedge method is carried out by the same method, and pavements from a mixture of optimal composition - as well as gravel pavements (Tables 12.4.2 and 12.4.3).

Table 12.4.2

Cost of materials for repairs

Table 12.4.3

The composition of the link and labor costs

Ruts and small ridges formed under the influence of traffic are leveled with heavy rollers, after moistening the coating. This method is used to eliminate small irregularities on a fairly durable coating. In other cases, ruts are eliminated by patching.

Crushed stone and gravel coatings treated with organic binders. In the process of repair, potholes, damage and uneven edges, bumps and sagging, small breaks and subsidence of the coating are eliminated.

Patching is carried out mainly with cold crushed stone (gravel) mixtures treated with organic binders.

In some cases, it is allowed to use cold or hot asphalt concrete mixtures or the direct or reverse impregnation method. In cold mixes, liquid (or viscous) bitumen, coal tar, bitumen emulsions are used as a binder.

Repair is carried out: in a cold way, if the air temperature is not lower than 5 ° C and in a hot way, if the air temperature is not lower than 10 ° C.

The cold method is appropriate for potholes up to 3 cm deep, and the hot method for potholes deeper than 3 cm.

With any of the above methods, the repaired site is prepared, including trimming (scribing) the edges, cleaning from dust and dirt, treating the cleaned surface with an organic solvent (solar oil, kerosene) at a rate of 0.1 ... 0.15 l / m using spray guns or sprayers and applying liquid bitumen, residual bitumen (tar) with a viscosity of 20-70 or tar in the amount of 0.3 ... 0.5 l / m 3 heated to 60 ° C on it.

Immediately after priming, the pothole is filled with repair material, the layer thickness of which is determined taking into account the compaction coefficient.

When using hot mixes, the material is laid in one layer when the depth of the potholes does not exceed 5 cm, and in two layers if the depth is more than 5 cm, and carefully compacted in layers. If the impregnation method is used, crushed stone no larger than 0.8 of the depth of the pothole, but not smaller than 16 mm, is placed in the prepared pothole, and compacted. Then viscous bitumen or tar is poured at the rate of 0.8-1.0 l/m 2 for each centimeter of the depth of the pothole. The temperature of the binder during filling should be: bitumen grades BND 200/300, BND 130/200 - 120...160°C. Spilling binder, crushed stone of fraction 5...15 mm is distributed and compacted. Small repaired areas are compacted with rammers.

Plots of pavement damaged by numerous potholes are repaired with cards. Damaged sections of the edges of the pavement at the junction with the curb are corrected by the above patching methods, ensuring proper support from the side of the curb.

Asphalt concrete pavement. The main works for the repair of asphalt concrete pavements include the restoration of worn top layers, the elimination of damage in the form of potholes, cracks, individual waves, bumps and sagging, breaks and uneven edges, surface treatment, protective layers and wear layers. These works are started in the spring with the onset of warm and stable weather. Repair work begins with patching potholes using patching methods using cold milling of the coating. Milling is carried out using cold milling machines. Specifications a number of cutters firm "Wirtgen" are given in table. 12.4.4.

Table 12.4.4

Technical characteristics of milling cutters "Wirtgen"

Options	Mill brand
W 350	W 500	W 600 D C	W 1000 F	W 1200 F
Milling width	350 mm	500 mm	600, 500, 400 mm	1000 mm
Milling depth	0...100 mm	0...160 mm	0...300 mm	0...315 mm	0...315 mm
Engine power	35 kW (48 hp)	19 kW (107 hp)	123 kW (167 hp)	185 kW (252 hp)	185 kW (252 hp)
Operating weight	4400 daN (kg)	7400 daN (kg)	12030 daN (kg)	17300 daN (kg)	17300 daN (kg)
Milling drum drive	mechanical	hydraulic	mechanical	mechanical	mechanical
Number of wheels			3 (optional equipment 4)
ground drive	guide / front wheels	guide / front wheels	guide / front wheels	guide / front wheels	guide / front wheels

When repairing, the general technological sequence is observed, which includes preparing the damaged area, preparing, laying and leveling the mixture, and compacting.

Hot and cold asphalt mixtures, poured asphalt, crushed stone and gravel materials treated with an organic binder serve as repair materials. Hot asphalt mixes and cast asphalt are mainly used on non-roads of categories I and II.

Repair of coatings using hot asphalt mixes is carried out in dry and warm seasons at an air temperature of at least 10°C. Molded asphalt can be laid even when low temperatures air - up to -5°С.

The preparation of the repaired site is carried out in the following order: the boundaries of the potholes are outlined in straight lines, capturing the undamaged part of the coating by 3-5 cm, several small potholes, closely spaced from each other, are combined into one common card; old asphalt concrete is removed along the outlined contour, the pothole is cleaned and (if necessary) dried; the bottom and its walls are primed with a bitumen emulsion with liquid or viscous bitumen heated to 60 ° C, at a rate of 0.3-0.5 l / m 2.

After the preparatory work, the pothole is filled with repair material, taking into account the safety factor for sealing. If the depth of potholes is up to 5 cm, the mixture is laid in one layer, more than 5 cm - in two layers.

Small potholes isolated from one another are compacted with electric or pneumatic rammers, manual vibratory rollers, and large areas are compacted with smooth-roller rollers weighing 4-10 tons. The best results are achieved when using rollers with rubber-coated rollers.

Compaction is carried out from the edges to the middle, while the surface of the repaired places after compaction should be at the level of the coating. Approximate indicators of work are given in table. 12.4.5.

Table 12.4.5

Labor costs and output during pavement repair

When filling potholes deeper than 5 cm, when not only the upper, but also the lower layer of asphalt concrete is removed, the work procedure does not change: a coarse-grained mixture is placed in the lower layer and compacted, then a fine-grained mixture is placed in the upper layer and compacted. If the pothole is up to 8 cm deep and there is no coarse-grained mixture, a medium-grained mixture is laid in two layers. Fine-grained or sandy mixture is used only for the top layer.

When using burners infrared radiation the pothole, cleaned of dust and dirt, is heated to 140-170 ° C, the heated edges are scraped to a depth of 1-2 cm, the bottom of the pothole is loosened, and the boiled material is distributed along the bottom and the required amount of a new mixture is added, compacted (if it is not cast mixture) to the desired density. The amount of the added mixture is set according to the size and depth of the pothole, taking into account the settlement during compaction (Table 12.4.6).

Table 12.4.6

The need for a mixture

Hollow depth, mm	The amount of the added mixture, kg with the area of ​​the pothole, m 2
0,1	0,2	0,3	0,4	0,5	0,6	0,7	0,8	0,9

When sealing potholes that are dangerous for traffic, in early spring or autumn, when the coating is wet and the air temperature is above 0 ° C, it is recommended to use crushed stone materials treated with bitumen with surfactants. For the same purpose, the mineral material is treated with activators - lime or cement - 1.5 ... 2% by weight of the mineral material.

Influxes, waves and shifts on the coating are eliminated by patching or cut off with a motor grader knife (after they have been preheated) with subsequent surface treatment. For heating, self-propelled asphalt heaters with infrared burners ( working speed movement 0.5...3.0 m/min). Cracks in the coating are closed when they are open - in dry and warm weather, the temperature is not less than 5 ° C. Cracks with a width of 5 mm or more are sealed with mastic, and small ones are filled with bitumen and sprinkled with stone fines. Separate cracks with a width of more than 5 mm are sealed as follows: they are cleaned of dust and dirt with compressed air, a brush or metal hooks; moistened with an organic solvent (solar oil, kerosene) at a rate of 0.1 ... 0.15 l / m 2 using spray guns or spray guns with a small spray angle; poured bituminous mastic(Table 12.4.7). Cracks are filled with excess. After removing the excess mastic, the crack is sprinkled with hot stone cuttings or sand. Cracks with destroyed edges are cut by cutting or milling asphalt concrete with a strip of 10 ... 15 cm on each side for the entire thickness of the deformed layer. Cutting down the material can be replaced by heating with infrared burners.

Road-climatic zone	Mixture number	Composition of the mixture, % by mass
bitumen grade BND 90/130 or BND 60/90	mineral powder	rubber crumb	asbestos crumb
II
II and III					-
			-
III and IV					-
			-
IV and V

On coatings containing organic binders, including asphalt concrete, during repairs, a single or double surface treatment is arranged or thin layer from asphalt concrete and similar mixtures (Table 12.4.8). Prior to performing these works, the coating must be cleaned of dust and dirt, potholes eliminated and cracks repaired.

Table 12.4.8

Single surface treatment device on asphalt concrete and other black surfaces (per 1000 m 2 of coating)

Type of work	The composition of the link	Labor intensity, man-hour
Cleaning the coating from dust and dirt in six passes of a mechanical brush	Machinist of the 4th category - 1	0,25
Having solved bitumen with an asphalt distributor (norm 0.5 ... 1.1 l / m 2)	Machinist of the 5th category - 1	0,43-0,45
Distribution of measured crushed stone by the T-224 distributor (norm 15 ... 30 kg / m 2)	Driver of the 5th category - 1, road workers of the 3rd category - 2	0,39
Compaction (rolling) of black crushed stone with a light roller (5 ... 6 tons) in 5 ... 6 passes along one track	Machinist of the 5th category - 1	2,1
Compaction of black crushed stone with a heavy pneumatic roller (10 ... 16 tons) in 5 ... 6 passes along one track	Machinist of the 5th category - 1	1,5

The repair of asphalt concrete pavements also includes work to restore the continuity and evenness of the upper layer using thermal profiling technology based on the principle of regeneration (restoration of lost properties).

Improving the adhesion properties of asphalt concrete and cement concrete pavements is carried out mainly by means of a double surface treatment device. The technology for performing work is described in Section 4.

For surface treatment on cement concrete pavements, it is advisable to use a rubber-bitumen binder: bitumen BND 60/90 or BND 90/130 from 85 to 91%; coal oil - 6...10%; crumb rubber - 3...5%.

Bituminous binder is prepared in boilers with a paddle mixer. First, dehydrated and heated to 150-160 ° C bitumen is loaded into the mixer in the amount of 10% of the required volume, then the calculated amount of dehydrated and heated to 40 ... 70 ° C coal oil and the mixture is thoroughly mixed for 10 ... 15 minutes . In the bitumen liquefied in this way, a predetermined amount of dried rubber crumb, sifted through a mesh with 3 mm holes, is added in small portions. The mixture is stirred for 1.0...1.5 h at a temperature of 150-160 °C. Then, without stopping mixing, the rest of the dehydrated and heated to 160 ° C bitumen is loaded. All components are finally mixed for 30 minutes at a temperature of 160 °C. Surface treatment device technology is described in section 4.

The scope of work on the arrangement of wear layers, as well as indicative indicators of work are given in table. 12.4.9

Table 12.4.9

The device of a wear layer 1.5-3 cm thick from asphalt concrete and similar mixtures on black coatings (per 1000 m 2 of coating)

Type of work	The composition of the link	Labor intensity, man-hours
Cleaning the coating from aching and dirt with a mechanical brush	Machinist of the 4th category - 1	0,25
Priming of the coating with liquid bitumen distributed by an asphalt distributor (norm 0.5 l / m 2)	Machinist of the 5th category - 1	0,24
Asphalt paver DS-181	Machinist of the 6th category 1, asphalt concrete workers: 5th category - 1, 4th category - 1, 3rd category - 3, 2nd category - 1, 1st category - 1	21,6 (2,7)
Pre-compaction of the layer with light rollers in 5-8 passes on one track	Machinist of the 5th category - 1	5,2
Compaction of the layer with heavy rollers on pneumatic tires in 10-12 passes along one track	Machinist of the 5th category - 1	7,6

Thermal profiling of asphalt concrete pavements. To restore the top layer of asphalt concrete pavements, technology based on the regeneration of pavements with the help of special machines is increasingly being used.

Regeneration is performed by various methods of thermal profiling, the main operations of which are: heating the coating; loosening (milling) it to a depth of 2-5 cm; loose mix planning; seal. Thermal profiling methods have varieties: thermal planning; thermohomogenization; thermal styling; thermal mixing; thermoplasticization.

Thermal planning method- the most simple, involves the implementation of only the basic operations indicated above. Average depth loosening of the repaired pavement depends on a number of factors, including the type of asphalt concrete and air temperature (Table 12.4.10).

Table 12.4.10

Average loosening depth

In the thermal planning mode, sandy asphalt concrete pavements are repaired with water saturation not exceeding 3% by volume (1.5% for areas with excessive moisture).

When repairing a pavement made of fine-grained asphalt concrete with a water saturation not exceeding 4% (3% for areas with excessive moisture), or sandy with a water saturation of more than 3% (up to 4% inclusive), thermal planning is combined with surface treatment or a wear mat. In this case, correction of the transverse slope is achieved. coverage up to 4%.

In other cases, after thermal planning, lay on the coating protective layer from new asphalt mix. It is most efficient to carry out this operation in one thread with thermal planning. The paver moves 15-20m or thermal profiler. Due to the fact that the final compaction of the old and new mixtures is carried out in one layer, its density increases. In addition, the thickness of the protective layer of the new mixture can be reduced to 1-2 cm versus 3 cm in the traditional way. This mode is a variation of the heat styling method.

Thermohomogenization method differs from thermal planning in that, in addition to the main operations, it also provides for the regeneration of asphalt concrete by mixing the old asphalt concrete mixture. This increases the homogeneity of asphalt concrete and improves the compaction of the layer, which makes it possible to somewhat expand the scope of this method compared to the previous one.

Coatings with water saturation not exceeding 4% are repaired by the thermohomogenization method. Thermohomogenization is carried out using thermal profilers equipped with a stirrer in the form of one machine or a set of machines.

heat laying method, in addition to the basic operations, it provides for the addition of a new mixture in the form of an independent layer over the loosened old mixture.

This method, unlike the previous ones, has a wider scope, since it allows repairing pavements with large amplitudes of irregularities, deeper ruts, significant pitting, unsatisfactory transverse slopes and higher water saturation. In addition, this method is effective when, for some reason, the coating cannot be loosened to a depth equal to or greater than the minimum allowable.

Heat laying can be used to repair coatings with water saturation up to 6%. The amount of added new mixture depends on the evenness of the repaired coating, the degree of its wear and is usually assigned within 25...50 kg/m 2 . If it is necessary to correct the transverse slope of the pavement by more than 4%, the consumption of the added asphalt concrete mixture is increased (Table 12.4.11).

Table 12.4.11

Increasing the consumption of the added mixture

The advantage of the heat laying method is the possibility of simultaneous compaction of the old and new mixture in one layer, which increases its density. Thermal laying is carried out using a thermal profiler equipped with equipment for receiving and distributing a new mixture in the form of a single machine or a set of machines. You can also use an equipment kit that includes a paver to add new mix.

thermal mixing method unlike thermal laying, it involves mixing the new added mixture with the old one and laying the resulting mixture in one layer.

Its advantage is the possibility of correcting to a certain extent the composition of the old mixture and its regeneration. When performing work in this way, no requirements are imposed on the old coating that limit its water saturation. The flow rate of the added mixture is set depending on the evenness of the repaired pavement, the degree of its wear and the desired change in the properties of the old asphalt concrete. Thermal mixing is carried out using a thermal profiler, equipped, in addition to the equipment for thermal laying, also with a stirrer.

Thermoplasticization method differs from the previous ones by adding a plasticizer to the old mixture in an amount of 0.1-0.6% by weight of the latter. This operation must be accompanied by mixing. The method has all the advantages of thermoplanning and thermohomogenization, since it does not require the addition of a new mixture. In addition, it allows you to regenerate old asphalt concrete, expands the scope of this method, extending it to pavements with water saturation exceeding 3%. (The only limitation on the applicability of the thermoplasticization method is the presence of large irregularities on the coating and heavy wear, requiring the addition of a mixture. Thermoplasticization is carried out by the same machines as thermohomogenization, provided that they are equipped with a plasticizer injection unit. It is advisable to use oils of petroleum origin containing aromatic hydrocarbons as a plasticizer not less than 25% by weight.The most accessible renobit is a plasticizer proposed by GiprodorNII.It is also possible to use extracts of selective purification of oil fractions of oil, motor oil. physical properties plasticizers must meet the requirements:

Kinematic viscosity at 50°С, m2/s........(25...70) 10 6

Flash point in an open crucible, °С, not less....100

Mechanical impurities, % mass fraction, not more than... 2.0

Water, % mass fraction, no more...................4,0

Fuel, % mass fraction, no more.............6,0

The plasticizer consumption depending on the depth of loosening of the coating and the speed of the thermal mixer is given in Table. 12.4.12.

Table 12.4.12

Plasticizer consumption rates, l/min

Loosening depth, cm	Dosage of plasticizer, % by weight of asphalt concrete mix
0,3	0,5	0,7
Machine speed, m/min
1,5	2,0	2,5	3,0	1,5	2,0	2,5	3,0	1,5	2,0	2,5	3,0
	0,8	1,1	1,3	1,5	1,3	1,8	2,2	2,5	2,3	2,6	3,0	3,5
	1,2	1,5	2,0	2,3	2,0	2,5	3,3	3,8	2,8	3,5	4,7	5,4
	1,6	2,0	2,6	3,1	2,7	3,3	4,3	5,2	3,7	4,7	6,1	7,2
	2,0	2,6	3,3	3,8	3,3	4,3	5,5	6,3	4,6	6,1	7,7	8,9

Thermal profiling without the use of an additional asphalt heater for all methods (except for the third one with a consumption of a new mixture of more than 25 kg/m3) is carried out at an air temperature of at least 15 °C; in the third method, at a flow rate of a new mixture of 25 ... 50 kg / m 2, work is carried out at an air temperature of 10 ° C and above, and at a flow rate of more than 50 kg / m 2 - 5 ° C and above.

With the use of an additional asphalt heater, work by all means can be performed when the air temperature is not lower than 5 °C.

Thermal profiling works are carried out at a wind speed of not more than 7 m/s. The temperature on the surface of the heated asphalt concrete pavement should not exceed - 180°C during the first and third methods of thermal profiling (the consumption of a new mixture is less than 25 kg/m2).

The temperature of the mixture in front of the tamper bar in all thermal profiling methods (except for the fifth one) should not be lower than 100°С, in the fifth method - not lower than 85 °С.

The specialists of the Ministry of Construction of Ukraine have established the following duration of heating of the layer of asphalt and tar concrete coating to an average temperature of 110 and 80°C, respectively (Table 12.4.13).

Table 12.4.13

Coating heating time

Note.In the numerator- heating time of asphalt concrete to an acceptable temperature of 200°C, and the denominator - tar concrete to an acceptable temperature of 125°C.

Estimated resource requirements for various ways of repairing asphalt concrete pavements (per 1000 m) are given in Table. 12.4.14.

Table 12.4.14

Resource requirement

Repairwithusing cast asphalt and cold organo-mineral mixtures. AT In accordance with the provisions of the current regulatory documents, repairs using poured asphalt type V can be carried out almost throughout the year (at temperatures down to -10 °C) [54].

Preparatory work is carried out in accordance with established requirements. In winter, the preparatory work includes cleaning the repaired maps from sand and salt deposits, snow, ice, and removing water.

Transportation of the mixture to the place of work is carried out in special self-propelled units with a thermos boiler or bunker, equipped with heating and a mixer. During transportation, continuous mixing and a temperature of the mixture of 180-240 ° C should be ensured, and, if necessary, batch unloading with varying the speed of the mixture.

Before loading, the thermos boiler (bunker) is heated for 10 minutes by two heaters or a nozzle to 180-190°C. The lid of the feed opening must be opened no earlier than 5 minutes before loading the boiler with the mixture.

It is forbidden to turn on the agitator drive clutch before starting the engine, as well as the agitator drive until the hopper is warmed up and if there are residues of a hardened (non-heated) mixture in it that prevents the movement of the agitator blades. During transportation, the total mixing time of the mixture in a mobile unit should be at least 20 minutes.

Arriving at the place of laying, the self-propelled unit is installed in front of the prepared pit in such a way that the outlet tray, when the boiler (bunker) is tilted, is directed directly into the pit. The mixture is unloaded when the outlet chute is tilted with simultaneous operation of the paddle mixer in the boiler. Works on the distribution of the mixture with distribution to the edges of the map and removal of excess, as well as smoothing and grouting of the junctions, are performed manually.

A separate operation is the distribution of black (or untreated) crushed stone over the surface of a freshly laid cast mixture to ensure the required adhesion properties in the repaired areas.

Crushed stone with a size of 3-5 (8) or 5-8 (10) mm is delivered to the place of repair work by dump trucks in the amount necessary for uninterrupted operation. The scattering of crushed stone is carried out in a uniform layer into one crushed stone immediately after the distribution of the mixture. The approximate consumption of crushed stone for a mixture of type I is 5 ... 8 kg / m 2. After the coating has cooled down to a temperature of 80-100 ° C, it is allowed to roll the distributed crushed stone with a hand roller weighing 30-50 kg. After the laid layer has cooled to the outside temperature, the unburned gravel should be swept away.

The movement of road transport on the finished coating opens when the coating reaches the outside temperature, but not earlier than 3 hours after the completion of the work.

With small volumes of repair with cards up to 3 m 2 (most often emergency), it is advisable to use cold organo-mineral mixtures. In the construction season, at an air temperature above 5 ° C, a mixture of grade I is used for repairs, in winter - grade II. Unlike the previously described repair methods with small cards, in this case it is allowed to lay the mixture even in rainy weather [54]. As with repairs using poured asphalt, there is no need to treat the prepared maps with bituminous materials. The need for special compaction of the laid organic-mineral mixture is also excluded.

The mixture is distributed into the prepared card manually with a compaction safety factor of 1.25-1.30. After distribution, it is enough to roll the mixture with the wheel of any car, including cars, in one pass along one track. It is possible to use vibrating plates for this purpose.

Traffic on the repaired area can be opened immediately after rolling. The final formation of the organo-mineral mixture layer occurs during the operation of the road surface under the influence of a traffic load.

Repair of coatings using organo-mineral mixtures in the areas of acceleration and deceleration of vehicles (crossroads, public transport stops) due to the peculiarities of the formation of the layer can only be a temporary measure, for example, emergency repairs in rainy or winter periods. A longer service life of such cards (directly proportional to the intensity of vehicle traffic) is noted in the haul sections.

Abroad, during current repairs using such materials, it is allowed to lay them directly into potholes (without preparing maps) with a minimum depth equal to the size of coarse aggregate.

Based on the results of a survey of repaired sections at federal road network facilities, it was found that the optimal layer thickness in a dense body should be considered to be at least two diameters of coarse aggregate.

The main condition for the correct assignment of the repair method is to determine the cause of the crack formation, the degree of destruction of the base and coating materials, the reasonable timing of the repair work and the economic feasibility of the cost of repair work.

Planned work on sealing temperature cracks should be carried out during periods of their maximum opening. The most optimal periods are spring with the onset of dry and warm weather or late autumn when night frosts cause compression of the asphalt concrete of the road surface, but during the day it is relatively warm (not lower than 5...10 °C).

When sealing cracks, in addition to their sealing, a “soft hinge” should be created from the repair material between the layers of asphalt concrete separated in the horizontal plane. Therefore, in the warm season, when the cracks are opened to a smaller width, it is recommended to additionally cut them with the formation of a deformation chamber (reservoir).

Table 12.4.15

Parameters of deformation chambers

Calculation of the chamber width can be performed using a simplified formula

AT= 100 b · To one · T/l , (12.4.1)

where b- distance between cracks, established during visual examination of the coating, mm;

To 1 - coefficient of linear thermal expansion of asphalt concrete, is taken depending on the brand and type of asphalt concrete, the type of used stone materials and binders, degree (approximately 2.1 ´10 ° for asphalt concrete of type "A" and "B"; 3.3 ´10 ° - asphalt concrete of type "C" and "D");

T- the difference between the air temperature during the period of work and the minimum possible temperature in the winter, ° С;

l- limiting relative elongation of the repair material at the minimum air temperature, % (according to the relevant regulatory documents, less than 50%).

In case of destruction of the edges of thermal cracks, the width of the chamber is taken not less than the width of the destruction.

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Full repair of the road should begin in cases where the number of general defects and damage reaches 12-15%. If there are fewer various deformations, cracks, chips, peeling, chipping and potholes, the so-called patching is carried out, the purpose of which is to ensure road safety. To do this, use different methods, tools, materials.

The main causes of roadway violations are the low quality of the materials used and the violation of technological processes, the most common of which is insufficient compaction. As a rule, road repairs are carried out in the warm season in dry weather, but sometimes there is a need for urgent restoration of the roadbed, and then work is carried out in almost any weather conditions.

Construction technology is constantly being improved, which makes it possible to make roads of the highest quality and increase their service life. The additives used in the composition of the asphalt concrete mixture allow the formation of a minimum number of cracks. As for the latter, they tend to increase in size by spring. And this is explained by the properties of water, which, getting into even the smallest crack in winter, freezes and expands.

Hot and cold mixes

The main percentage of pavement is asphalt concrete pavement, therefore, most often, when repairing them, they resort to using a hot mix of asphalt and concrete. The starting materials for the preparation of the mixture are sand, crushed stone, bitumen and mineral powder. Such material is characterized by high embedding properties.

Hot mix asphalt and poured asphalt are used in the repair of roads of the first and second categories. The temperature of the hot mix is ​​approximately +150°C. They deliver it to the place of repair in special bunkers that maintain heat. According to the standards, the mixture, the temperature of which is below +110 ° C, is considered a marriage. Thermos hoppers with a capacity of up to 4 m3 are able to provide a mixture of approximately 100 holes with a size of 100x100 cm and a depth of 5 cm.

Depending on weather conditions, cold bituminous mixtures, materials based on bitumen emulsions and thinned bitumen can be used. Cold technologies are relevant for roads of the third and fourth categories, since the strength and water resistance of such mixtures are approximately three times lower than those of hot ones.

As for bitumen emulsions, they are actively used in road repair in many countries, primarily because they are highly economical, not demanding on weather conditions, and their service life is quite long. For emergency repairs, minor repair of defects, less common and non-traditional mixtures based on polymer, cement, polymer-bitumen and other binders can be used.

Recycling technology and jet-injection methods

This technology provides for the recycling of asphalt concrete material and its use for repairing the road surface directly on site. Pieces of asphalt, scrap and milling products are heated and thoroughly mixed in a special machine - a recycler. Gravitational mixing takes place in a cylindrical drum with blades and a burner. The most efficient way to recycle asphalt crumb, to which bitumen is subsequently added. The resulting mixture is immediately applied to the prepared place. Thus, it is possible to reduce repair costs by up to 60%.

The jet-injection technology, in which the necessary operations are performed by one machine, is also becoming more widespread. The essence of the technology is high-speed air blowing, instant flushing and application of bitumen emulsion. In this case, breaking and milling of asphalt concrete may not be carried out. The pothole is filled with crushed stone of a fine fraction, mixed with a bituminous emulsion (rapidly decomposing cationic or anionic 60% concentration). High air velocity provides good compaction and no need to use vibratory plates and vibratory rollers.

Stages of proper preparation before patching

With proper patching and proper preparation, the pavement lasts up to 5 years. To do this, the basic requirements must be observed and the results of practical experience and new developments should be taken into account. Preparation consists of several stages.

• Markup. Potholes are indicated by straight lines along the axis of the road and across. In this case, the margin of the undestroyed layer should be approximately 3-5 cm. If several potholes are located side by side, they are combined with one contour.
• Removing small potholes. The process takes place with the help of a jackhammer (possibly pneumatic) with an appropriate nozzle.
• Removal of long and narrow potholes with an area of ​​more than 3 m2, large cracks. In this case, a cold cutter works (it can be self-propelled, trailed, mounted), which removes the coating over its entire thickness of the layer along the outlined contour, resulting in the formation of pits correct form with vertical walls. Some models of cold milling machines feed the cut material into a special loader bucket or body, reducing the amount of manual work.
• Cleaning new pits from crumbs, small pieces, dust, treating the walls and bottom with liquid bitumen or a bitumen-containing emulsion. The amount of lubricant should not be excessive, otherwise the quality of adhesion of the new layer of the road surface to the old one is reduced. For lubrication, small-sized installations are most often used, which spray the mixture with a small pressure from a hose.

The choice of one or another method of patching must always meet certain criteria and requirements. As a result, the repaired site will serve for a long time.