INTERSTATE STANDARD

ASPHALT CONCRETE MIXTURES
AND ASPHALT CONCRETE
STONE AND MASTIC

TECHNICAL CONDITIONS

INTERSTATE SCIENTIFIC AND TECHNICAL COMMISSION
ON STANDARDIZATION, TECHNICAL REGULATION
AND CERTIFICATIONS IN CONSTRUCTION (MNTKS)

MOSCOW

Foreword

1 DEVELOPED BY FSUE Soyuzdornii, Transstroy Corporation and the Office of Technical Regulation, Standardization and Certification in Construction and Housing and Public Utilities of Gosstroy of Russia

INTRODUCED by Gosstroy of Russia

2 ADOPTED by the Interstate Scientific and Technical Commission for Standardization, Technical Regulation and Certification in Construction (ISTCS) on October 17, 2002

3 INTRODUCED FOR THE FIRST TIME

4 This standard takes into account the main provisions of international ISO standards [, ], European standard pr EN 13108-6, Finnish Asphalt Norm 2000 and German Technical Directives ZTV Asphalt - StB 02

5 INTRODUCED since May 1, 2003 as a state standard Russian Federation Decree of the Gosstroy of Russia dated April 5, 2003 No. 33

Introduction date 2003-05-01

1 area of ​​use

This standard applies to hot crushed stone mastic asphalt mixes and crushed stone mastic asphalt concrete used for the construction of the upper layers of pavements of roads, airfields, city streets and squares.

The requirements set out in sections , , and are mandatory.

2 Normative references

The list of interstate standards, references to which are used in this standard, is given in the Appendix.

3 Definitions

For the purposes of this International Standard, the following terms apply with their respective definitions.

Crushed stone-mastic asphalt mix (ShMAS) - a rationally selected mixture of mineral materials (crushed stone, sand from crushing screenings and mineral powder), road bitumen (with or without polymeric or other additives) and a stabilizing additive, taken in certain proportions and mixed in a heated state.

Crushed-stone-mastic asphalt concrete (ShMA) - compacted crushed-stone-mastic asphalt-concrete mixture.

Stabilizing additive - a substance that has a stabilizing effect on SMAS and ensures its resistance to delamination.

4 Main parameters and types

Crushed-stone-mastic asphalt concrete mixtures (hereinafter referred to as mixtures) and crushed-stone-mastic asphalt concrete (hereinafter referred to as asphalt concrete), depending on the fineness of the crushed stone used, are divided into types:

ShMA-20 - with the largest grain size up to 20 mm;

ShMA-15 - »»»»» 15 mm;

Shchma-10 - »»»»»10 mm.

5 Technical requirements

5.1 Mixtures must be manufactured in accordance with the requirements of this standard according to the technological documentation approved in the prescribed manner by the manufacturer.

5.2 Grain compositions of the mineral part of mixtures and asphalt concretes must correspond to those indicated in the table.

Table 1

Percent by weight

/ Crushed-stone-mastic asphalt concrete

General information about crushed-stone-mastic asphalt concrete (ShMA)

Crushed-stone-mastic asphalt concrete (ShMA)- compacted crushed-stone-mastic asphalt-concrete mix.

Crushed-stone-mastic asphalt mix (ShMAS)- artificial road building material, which is a mixture of mineral materials (crushed stone, sand from crushing screenings and mineral powder), bituminous binder and stabilizing additive.

Purpose and scope of SMA

The main purpose of crushed stone mastic asphalt is the construction of top layers of the road surface with a thickness of 3 to 6 cm. In some cases, when the road surface is in good condition, but still requires some improvement in surface performance (roughness, tire grip), - mastic asphalt can be used for thin-layer surface treatment.

The main field of application of crushed stone-mastic mixtures is the asphalting of motor roads of category I–III, city streets with heavy traffic, as well as high-speed highways with a high traffic load. In addition, the popularity of crushed-stone-mastic asphalt as a material for constructing runways and taxiways at airfields is growing every year.

Typical composition and production technology of crushed-stone-mastic asphalt

Crushed-stone-mastic asphalt concrete mixture includes 3 components:

• mineral material (crushed stone, sand, mineral powder);
• bitumen binder;
• stabilizing additive;

Crushed stone (stone mineral material) forms the structural frame of the crushed stone-mastic mixture, and mastic fills the voids in the crushed stone frame (the volume of which is about 20%).

Mastic- asphalt binder, which is a mixture of sand, mineral powder, bituminous binder and stabilizing additive.

As mineral material when preparing a crushed stone-mastic mixture, crushed stone, sand, and also mineral powder are used.

• rubble- the most important structural element crushed-stone-mastic asphalt concrete. It ensures the creation of a stable frame in the paving layer. The share of crushed stone in the total mass of SMA reaches 70–80%. To prepare the crushed stone-mastic mixture, fractionated crushed stone is used (the most popular fractions are 5–10 mm, 10–15 mm and 15–20 mm) with an improved (cubic) grain shape and high roughness. The content of flaky (lamellar) and needle-shaped grains should not be more than 15% of the total mass of crushed stone. In some cases, it is allowed to use crushed stone from metallurgical slags.
• Sand used for the preparation of SMA, should be only from screenings of crushing rocks.
• mineral powder used for the production of crushed stone-mastic mixtures, is similar to that used in the production of conventional asphalt mixtures. It is obtained from limestone, dolomite and other carbonate rocks.

As a bituminous binder in the preparation of crushed stone-mastic mixtures, viscous petroleum road bitumen with or without modifying additives, as well as polymer-bitumen binders (PBV) is used.

Stabilizing additive is an obligatory component of crushed-stone-mastic asphalt. It is required in order to hold the bituminous binder on the surface of the grains of the mineral material, thus preventing delamination that can occur during intermediate storage and transportation of the hot macadam-mastic mixture to the laying site. As a stabilizing additive, cellulose fibers or pressed granules of cellulose fibers, as well as polymer or mineral fibers are used. The most widely used are stabilizing additives for SMA based on cellulose fibers (VIATOP, TOPCEL, ANTROCEL, etc.).

Production technology of crushed stone-mastic asphalt concrete mix is similar to the preparation of conventional asphalt mixtures and is carried out in standard asphalt mixing plants, additionally equipped with a system for supplying a stabilizing additive.

Types of crushed stone-mastic asphalt concrete mixtures

According to the DSTU B.V.2.7-127:2015 in force in Ukraine “Asphalt concrete mixes and crushed stone-mastic asphalt concrete. Specifications”, depending on the crushed stone fraction, the following types of SMA are distinguished:

• ShMA-20 ( largest size crushed stone grains up to 20 mm). It is used for the device of the upper layers of the road surface with a thickness of 4–6 cm.
• ShMA-15 (... up to 15 mm). It is used for the device of the upper layers of the road surface with a thickness of 3–5 cm.
• ShMA-10 (... up to 10 mm). It is used for the device of the upper layers of the road surface with a thickness of 2–4 cm.
• ShMA-5 (... up to 5 mm). They can be used for thin-layer surface treatment of the road surface.
• rShMA - crushed stone-mastic asphalt concrete mixtures based on a modified rubber-bitumen binder (in DSTU B.V.2.7-127: 2015 this species SMA is not defined).

European standards for crushed stone mastic asphalt (European standard for SMA prEN 13108-6) provide for the following types of it, depending on the fraction of crushed stone:

• SMA 0/8 (with maximum size crushed stone grains up to 8 mm)
• SMA 0/11 (… up to 11 mm)
• SMA 0/16 (… up to 16 mm)
• SMA 0/22 (... up to 22 mm)

In addition to these types, European standards allow the use of both smaller fractions (up to 4 mm) and larger fractions of crushed stone (up to 40 mm) in SMA.

Difference of ShchMAS from conventional asphalt mixes

Hot compacted macadam-mastic mixtures are an independent type of asphalt concrete mixtures. The main differences between SMA and conventional asphalt concrete include:

• Increased content of crushed stone (20–30% more compared to type “A” asphalt concrete mixes)
• Increased content of bituminous binder (from 5.5 to 8%)
• Tighter tolerance for the size and shape of crushed stone
• The presence of a stabilizing additive

The main advantages of crushed-stone-mastic asphalt concrete

Long-term practice of using crushed-stone-mastic asphalt in the road construction industry and a large number of tests carried out confirm it. high efficiency, economic feasibility and ease of use for the installation of the upper asphalt layers of the road surface. Today, in many developed countries, crushed-stone-mastic asphalt is becoming the main material used in the asphalting of high-speed roads, highways and runways of airfields. Its main advantages are:

• Waterproof and frost resistant. They are achieved due to the high content of bituminous binder, as well as the low residual porosity in the compacted state.
• High fatigue resistance. It is achieved due to the dispersed-reinforcing action of the stabilizing additive, as well as a high binder content and low residual porosity.
• Increased shear stability. It is due to a higher, in comparison with standard asphalt concrete, static shear yield strength.
• Low abrasion and resistance to the damaging effects of studded car tires. It is achieved through the use of crushed stone from durable rocks in the composition of the crushed stone-mastic mixture, as well as due to the high content of mastic (asphalt binder).
• Roughness of the pavement and high frictional properties (the level of grip of the road surface with the wheels). Helps improve traffic safety Vehicle at high speeds.
• Increased crack resistance. Although the degree of resistance of a crushed stone-mastic asphalt concrete pavement to thermal cracking depends to a greater extent on the composition of the crushed stone-mastic mixture, resistance to fatigue cracking is characteristic of all SMA.
• Low noise level. SMA coatings differ more low level noise from traffic than conventional asphalt pavements (on average by 4–5 dB).

The combination of the above advantages of crushed-stone-mastic asphalt concrete can significantly increase the turnaround time of the road surface, improve comfort, quality and traffic safety.

The history of the creation of crushed-stone-mastic asphalt

Crushed stone mastic asphalt was developed in Germany in the 60s of the XX century. The increased intensity of rutting, the destruction of the road surface due to the increase in the number of vehicles, as well as the active use of studded car tires (also invented in the 60s), laid the foundation for the development and testing of a new road construction material.

On the initial stage to combat the destruction of asphalt pavements and increased rutting, the problems were solved by filling defective areas with special mastic, followed by powdering with crushed stone and compaction. Coating areas repaired in this way showed a high degree wear resistance. But the technology had a number of significant drawbacks, namely: the high cost of work and low productivity due to the large amount of manual labor.

To eliminate these shortcomings, it was decided to transfer the mixture preparation process to a stationary asphalt concrete plant. However, when transporting the crushed stone-mastic mixture prepared at the plant to the asphalting facility, another problem arose - mixture delamination (leakage of bituminous binder from the surface of the mineral filler).

The key to solving this problem was the use of a stabilizing additive based on cellulose fibers. The original patent for the idea of ​​using natural cellulose fibers as a stabilizing additive for crushed stone-mastic mixtures (preventing binder leakage) was issued on July 30, 1968 construction company Strabag SE.

Subsequently, during numerous tests, it was repeatedly confirmed that road surfaces paved with the use of crushed stone-mastic asphalt concrete mixtures have higher operational characteristics compared to conventional asphalt concrete. The logical result of this was that in 1984 in Germany the first standard was adopted for the use of SMA in the performance of work related to the asphalting of the upper layers of the road surface.

Currently, in many countries of the world, crushed-stone-mastic asphalt is widely used as a material for the upper protective layers of the road surface. Crushed stone-mastic mixtures are gradually replacing other types of asphalt concrete mixtures intended for the installation of protective and structural layers.

State standard for SMA in Ukraine

In Ukraine, the first standard for crushed stone mastic asphalt (DSTU B V.2.7-127:2006) was adopted in 2006. From August 10, 2015 by order No. 191 of the Ministry regional development, construction and housing and communal services of Ukraine put into effect new standard at ShchMAS and Shchma DSTU B.V.2.7-127:2015 “Asphalt concrete mixes and crushed stone-mastic asphalt concrete. Specifications".

The standard applies to hot crushed stone-mastic asphalt concrete mixes and crushed stone-mastic asphalt concrete, which are used for the installation of the upper layers of the pavement of roads, airfields, bridges, streets. settlements, squares, driveways, roads and sites of industrial enterprises.

Asphalt paving technology using crushed stone-mastic mixtures

The operational characteristics and durability of the SMA pavement largely depend on compliance with the rules and requirements for the transportation of crushed stone mastic asphalt to the work site, its laying and the quality of compaction.

1. Transportation of SMA to the object. Delivery of hot crushed stone-mastic asphalt mix to the site should be carried out by dump trucks (if possible, equipped with a body heating system) with a protective waterproof awning that prevents the mixture from quickly cooling and moisture ingress.
2. Preparation of the underlying layer. Before laying crushed-stone-mastic asphalt, the surface of the underlying layer is cleaned of dust and dirt, after which it is treated with liquid bitumen or bitumen emulsion (using an asphalt distributor). If the lower layer of the asphalt pavement has significant defects, then before laying the SMA, it is milled and a leveling layer of the asphalt concrete mixture is laid using the continuous asphalt paving method. In case of minor damage, patching is carried out.
3. Schma laying. Asphalt paving works with the use of crushed stone-mastic asphalt concrete mixture must be carried out in dry weather, at an air temperature of at least 5 ° C in spring, and at least 10 ° C - in autumn. The thickness of the layer and the consumption of SMA during the construction of the upper layers of road surfaces are as follows:
   • ShMA-20 - thickness - 4–6 cm, mixture consumption - 100–150 kg / m 2
   • ShMA-15 - thickness -3–5 cm, mixture consumption - 75–125 kg / m 2
   • ShMA-10 - thickness - 2–4 cm, mixture consumption - 50–100 kg / m 2
   Asphalting is recommended using caterpillar asphalt pavers equipped with an automatic leveling and cross-slope system. Laying of crushed-stone-mastic asphalt is desirable to carry out on the entire width of the carriageway. To obtain the most even coverage, it is necessary to ensure the continuity of the laying of the SMA (using mobile loaders). The speed of laying the crushed stone-mastic mixture should be at least 2-3 meters per minute.
4. Shchma seal. At the initial stage, the crushed-stone-mastic mixture is compacted by heavy static smooth-drum rollers with a linear load of 22 to 30 kg/cm 2 . It is not recommended to use vibratory rollers due to the high sensitivity of crushed stone mastic asphalt to overconsolidation. The compaction procedure should be carried out at as much high temperature mixtures. Light and medium asphalt rollers are not used at the initial stage of compaction. Due to the high probability of sticking of the mixture, the use of pneumatic wheeled rollers is excluded.

Possible defects associated with a violation of the technology of laying SMA

Failure to comply with and violation of the rules for transporting, laying and compacting the crushed stone-mastic mixture can lead to the following defects:

• Protrusion of bituminous binder on the surface of the asphalt pavement. Occurs as a result of exceeding the norm of pouring bitumen emulsion or liquid bitumen when subpriming the underlying layer.
• The appearance of small arcuate cracks. Occurs due to the low temperature of the mixture during its compaction.
• The appearance of wide cracks. Occurs due to insufficient heating of the paver screed.
• Insufficient shear resistance of asphalt concrete. Occurs when using a geogrid with an incorrectly selected cell size.

Prices for crushed stone-mastic asphalt and the cost of laying it

The production of a crushed stone-mastic mixture costs approximately 30-40% more than a conventional type A asphalt concrete mixture. The higher cost of SMA is due to the use more bituminous binder and high-quality crushed stone, as well as the use of expensive stabilizing additives (which are mostly imported). As of June 2015, the cost of one ton of macadam-mastic mix of the ShchMAS-10 brand with the addition of Likomont was UAH 2,049, and the cost of the most expensive fine-grained asphalt concrete mix of type A was UAH 1,480 (prices of PJSC Asphalt Concrete Plant, Almaty). Kyiv on 10.06.2015). Thus, the difference in price between conventional asphalt mix and SMA is 38%.

The cost of laying 1 m 2 of crushed stone mastic asphalt is on average 10–20% higher than the cost of asphalting with conventional fine-grained asphalt. The difference in price is due to the fact that the installation of SMA is more technologically advanced, qualified and laborious process than traditional asphalt paving. Thus, the difference in the price of 1 m 2 of ordinary asphalt concrete and a high-quality road surface from SMA can be 40–60% (30–40% is the difference in the price of the material and 10–20% is the difference in the cost of work).

Nevertheless, despite the high cost of the material itself and its laying, the use of crushed stone mastic asphalt is economically viable and justified, since SMA can be laid in a thinner layer and, at the same time, has a longer service life (2–3 times more than conventional asphalt concrete), which reduces the operating costs of maintaining the road.

Asphalting in Kyiv using crushed-stone-mastic asphalt

Installation of high-quality and durable crushed-stone-mastic road surfaces. The whole range of services for asphalting roads and small areas in Kyiv and Kyiv region. Efficiency and quality work at affordable prices.

90. Installation of coatings from crushed stone mastic asphalt concrete.

Features of laying and compaction of SMA.

SMA is an independent type of asphalt concrete, which, unlike other types of mixtures, provides both water resistance, shear resistance and roughness of the top layer of the coating. The residual porosity of the compacted SMA layer can be less than 1%, but at the same time, the shear resistance and roughness of the coating remain at a fairly high level.

The original specification of the material allows it to be laid thin layers, respectively, for 1 m 2 of the surface, a smaller amount of this high-quality asphalt concrete mixture is required. SMA becomes profitable, although it contains more expensive and high-quality materials.

PERFORMANCE PROPERTIES OF COATINGS FROM SMA

The fact that crushed-stone-mastic asphalt concrete mixtures are becoming more and more popular in technically developed countries is a consequence of the combination of high performance and durability of pavements made from them.

positive properties of crushed-stone-mastic asphalt concrete:

Shear resistance at high operating temperatures;

Rough surface texture and good grip on the car wheel;

High wear resistance, including the action of studded tires;

Waterproof;

Crack resistance during coating deformations and mechanical impacts of vehicles;

Aging resistance.

SMA mixtures are prepared by mixing crushed stone, sand from crushed screenings, mineral powder and bitumen, taken in a rationally selected ratio, in asphalt mixing plants in a heated state, with the obligatory introduction of stabilizing additives such as fibers or polymers. They are added to the mineral part or to bitumen in order to prevent the binder from running off during the storage of the mixture in storage bins and during transportation, as well as to increase the uniformity and improve the physical and mechanical properties of asphalt concrete.

1.3. Depending on the size of the crushed stone used, the mixtures are subdivided into the following types: ShchMA-10, Shchma-15 and Shchma-20 with a fraction size of up to 10, 15 and 20 mm, respectively.

Crushed stone-mastic asphalt concrete mixes contain about 70 - 80% crushed stone with an improved (cubic) grain shape, which creates a stable frame when the coating is compacted. The high content of limestone mineral powder (8 - 15%) and bituminous binder (not less than 5.5%) ensures a low level of voids in the compacted coating layer. To structure and stabilize the bituminous binder, it is recommended to introduce special stabilizing additives, such as fibers.

INSTALLATION AND COMPACTION OF THE MIXTURE

SMA mixtures should be laid on a pre-prepared base surface at an ambient temperature of at least 5 °C.

If necessary, they carry out patching, cutting and sanitizing cracks in the old asphalt concrete pavement, milling the surface to the design mark or laying a leveling layer of asphalt concrete.

To ensure adhesion, the surface of the lower layer is cleaned of dust and dirt with mechanical brushes, compressed air from a mobile compressor or other means, after which it is treated with an organic binder: bitumen emulsion or liquid bitumen.

6.2. Low-viscosity bitumen emulsions or liquid bitumen, preheated to operating temperature, are applied to the surface to be treated. The primer is distributed by an asphalt distributor with a bitumen consumption of 0.2 - 0.3 l/m 2 . The milled surface requires 1.5 times more bitumen emulsion.

6.3. The hot macadam/mastic mix is ​​laid and compacted as a standard mix with conventional asphalt pavers and smooth rollers. It is recommended that paving be carried out to the full width of the carriageway, if possible, using crawler-mounted asphalt pavers equipped with automatic cross-slope leveling systems. The number of pavers working at the same time depends on the total width of the pavement and the width of the compacting working bodies. Asphalt pavers during laying should be placed in a ledge at a distance of 10 - 30 m from each other, depending on weather conditions.

6.4. When laying a layer not to the full width, the technological grips must correspond to the technique used and ensure the minimum length of the “cold” longitudinal and transverse joints when mating the stacked strips.

6.5. Before the start of laying, the asphalt pavers are set to their original position and prepared for work according to the operating instructions:

The screed is placed on wooden blocks (starting blocks) parallel to the base to the height of the design layer thickness and compaction allowance of 5–10% (design layer thickness) and then heated to a temperature of 150 °C for 10–20 minutes, depending on weather conditions;

Set the angle of attack to the screed 2 - 3 degrees;

Set up an automatic system for ensuring evenness and cross slope;

Check the conformity of the length and height position of the distribution auger of the stacker with the geometric dimensions of the laid SMA layer (the distance from the lower edge of the auger blade to the base surface should be approximately half the layer thickness);

Adjust the mixture supply sensors that maintain a certain level of material at the ends of the screw distributor;

The operating mode of the tamper bar and vibrating plate is set: the stroke of the tamper bar should be 5 - 6 mm, the frequency of impacts of the tamper bar is about 1000 min -1, the vibration frequency of the vibrating plate is within 40 Hz.

6.6. After the passage of the asphalt paver, the surface of the laid SMA layer should not have cracks, pits, discontinuities or other defects.

6.7. To receive flat surface wear layer, it is necessary to ensure the continuity of laying the crushed stone-mastic mixture. The recommended paving speed is at least 2 - 3 m/min and depends on the supply of asphalt mix to asphalt pavers.

Asphalt concrete mixture must be evenly delivered to all simultaneously working pavers.

6.11. Particular attention must be paid to the device of "cold" longitudinal and transverse joints when mating the stacked strips. The transverse mates must be perpendicular to the axis of the road. The edges of the previously laid strip are cut off vertically and smeared with bitumen or bitumen emulsion. The cold transverse joint must be warmed up, the paver should be installed in such a way that the vibrating plate is above the edge of the previously laid coating layer, then fill the auger chamber with hot mix.

6.12. During the operation of one stacker, the length of the laying strip, which makes it possible to ensure good mating of adjacent strips, is assigned in the range from 50 to 200 m, depending on the cooling rate. When laying the wear layer in conjugated strips, the work is organized so that at the end of the shift the layer is laid over the entire width of the coating. When pairing the hot mixture layer with the edge of the cooled coating, it is advisable to heat the latter with linear infrared heaters.

6.13. For compaction of SMA layers, heavy smooth-roller rollers weighing 8–10 tons are most suitable, the steel rollers of which are wetted during rolling with soapy water, water-kerosene emulsion or water. It is not recommended to use rollers on pneumatic tires, since at high temperatures sticking of bulk SMA bitumen to the tire rubber is possible. Only at the final stage of compaction with well-heated tires is it possible to use them.

6.14. The laid SMA layer should be compacted at maximum temperature with heavy static smooth drum rollers, which should move in short patches at a speed of 5 - 6 km/h as close to the paver as possible.

6.15. In the presence of transverse mates and longitudinal "cold" joints, sealing should begin with them. To connect the layer with the “cold” strip, it is necessary that the roller make its first pass along the previously laid laying strip, overlapping the freshly laid layer to a width of 20–30 cm. "cold" strip on the compacted freshly laid layer of hot mix.

6.16. In the process of compaction, the rollers should move along the rolling strip by shuttle from its edges to the axis of the road, and then from the axis to the edges, overlapping each track by 20 - 30 cm. The first pass must be started, stepping back from the edge of the coating by 10 cm. the passage of the rink along the entire length of the strip. The rolling scheme should provide uniform compaction across the entire width of the rolled sheet, which is achieved by the same number of roller passes along one track.

6.17. In the case of covering with mating strips, when compacting the first strip, it is necessary to ensure that the rollers of the roller are at a distance of at least 10 cm from the mating edge. When compacting the second strip, the first passes of the roller should be carried out along the longitudinal interface with the previously laid strip.

6.18. Compacting the SMA layer with a roller with vibration turned on is not recommended, and at a temperature of the crushed stone-mastic mixture below 100 ° C, laying the mixture on a rigid base, and also arranging thin layers of SMA is prohibited. Layers of increased thickness are allowed to be compacted with vibration only at a sufficiently high temperature of the mixture after one pass along one track of a smooth-roller roller of static action. For effective compaction, 1 - 2 passes are sufficient.

6.19. It is very important to carry out rapid densification of SMA at temperatures not lower than 80 °C, especially when laying thin layers of coatings, since their cooling occurs faster. Behind one asphalt paver, as a rule, there should be two heavy smooth-drum rollers of static action. The required degree of compaction of the SMA layer is usually achieved in 4 passes of the roller along one track.

The A&K group of companies produces and offers you to buy crushed-stone-mastic asphalt concrete Shchma-15 with delivery or for self-delivery at quite affordable price. This material is a hot mix asphalt based on a crushed stone frame. Empty spaces between large particles of crushed stone are filled with a mixture of mineral powder, bitumen and crushed sand.

Characteristics of ShMA-15

The crushed-stone-mastic ShchMA-15 differs from ordinary asphalt concrete in a fairly rigid frame structure in the coating. Such a frame transfers the load to the lower layers of the coating by means of large crushed stone particles in contact with each other. What does it give? The deformation of the pavement in all directions is significantly reduced, that is, the maximum resistance of the pavement to the effects of the traffic flow is achieved.

In addition, Shchma-15, bought from us at a low price with delivery, has the following characteristics:

• Increased moisture resistance;
• Durability finished coating, increased two to three times compared to conventional asphalt;
• High adhesion coefficient, permanently stable;
• Reduced hydroplaning effect;
• Reduced noise level when driving on the road;
• Full compliance with GOST is confirmed by official documents.

Application of crushed-stone-mastic asphalt concrete ShMA-15

Compacted crushed-stone-mastic asphalt concrete ShMA-15 is used for construction and overhaul top layers of road surfaces. It is used to create high-quality and reliable asphalting of city streets, sites and squares, airfields, etc.

Delivery of ShMA-15 to customers

Call us at A&K, and our managers will help you place an order for ShMA-15 and answer all questions about the purchase, delivery and use of the material. Delivery is carried out to all cities of the Moscow region.