KR100669079B1 - Powder type asphalt modifier and asphalt concrete using asphalt pavement and porous pavement - Google Patents

Abstract

Provided is an asphalt modifier, which improves high-temperature characteristics, low-temperature characteristics and aging characteristics of asphalt, and is useful for manufacturing asphalt concrete via plant-mix process. The asphalt modifier comprises: 10-80 wt% of rubber powder; 89-10 wt% of asphaltite powder; and 1-10 wt% of polyethylene powder used for reinforcing a powder mixture formed from the rubber powder and the asphaltite powder. The asphalt modifier is provided in the form of powder. The rubber powder includes powder obtained by processing waste tires. Additionally, the rubber powder is pulverized into a particle size of 0.4 mm or less.

Description

Asphalt modifier and its manufacturing method and method for producing asphalt concrete using asphalt modifier {powder type asphalt modifier and asphalt concrete using asphalt pavement and porous pavement}

1 is a flow chart showing an embodiment of a process flow of a method for manufacturing a room temperature of a powdered asphalt modifier in which a waste tire rubber powder, an asphaltite powder and a polyethylene powder are mixed according to the present invention.

Figure 2 is an embodiment flow diagram illustrating a process flow of a method for producing asphalt concrete of the dry method using a powdered asphalt modifier mixed with the waste tire rubber powder, asphaltite powder and polyethylene powder according to the present invention.

* Explanation of symbols for main parts of the drawings

110: waste tire rubber powder drying step 120: waste tire rubber powder measurement step

130: waste tire rubber powder input step 140: the first sifting step

150: asphaltite / polyethylene powder input step

160: second sifting step 170: mixing step

180: mixing state check step 190: remix step

The present invention relates to a powdery asphalt modifier, a method for producing the same, and a method for producing asphalt concrete in a dry method using the asphalt modifier. More specifically, a rubber powder and a natural resin in which waste tires are crushed to a particle size of 0.4 mm or less. Asphaltite powder and polyethylene powder, a kind of chemical resin, are mixed at room temperature and used as a modifier of asphalt, thereby improving asphalt's high / low temperature and aging characteristics and The present invention relates to a method of manufacturing asphalt concrete of a dry method, which is a method of directly inputting an asphalt plant using a method of manufacturing an asphalt modifier.

In general, asphalt refers to a black or dark brown semi-solid cross-linked substance remaining after the hard part of the constituents of the petroleum is evaporated by natural or artificial methods. It has a characteristic of gradually changing to a liquid phase. The asphalt is used as a bonding material or an adhesive material because it is excellent in adhesion and excellent adhesion to the mineral material, and is also used as a waterproofing material because it is insoluble in water and is insoluble in water. In addition, since the viscosity can be changed according to the purpose of use, the workability is also excellent. Due to these advantages and characteristics, asphalt has a wide range of applications, and is used for various purposes such as road pavement, dam construction, repair, waterproofing, general industrial use, and agricultural use.

Looking at the case of applying the asphalt to the road pavement, it is rare to use the asphalt itself as a typical example, it is used as an asphalt concrete made by mixing with aggregate and filler. The aggregate acts as a framework in the asphalt concrete to provide support, load distribution and frictional resistance. The aggregates are divided into coarse aggregates mainly used for crushed stone and fine aggregates mainly used for crushed sand and steel sand. The filler used to fill the voids of the coarse aggregate and the fine aggregate is also mixed with asphalt to improve peeling resistance, and fine powder of an inorganic material such as limestone powder is mainly used.

On the other hand, the asphalt is liquefied as the temperature rises without a clear melting point is transferred to the liquid phase, the consistency (constancy) changes with temperature is very large. The degree of this change is called temperature sensitivity. If the temperature sensitivity of the asphalt is too high, the asphalt concrete structural part is cracked by brittleness under low temperature conditions, and plastic deformation due to severe ductility occurs under high temperature conditions. In addition to the thermal sensitivity of the asphalt, the durability of the asphalt concrete (also called ascon) is determined by various conditions such as tensile strength and elasticity.

Asphalt modifiers are mixed with asphalt or added during the production process of asphalt concrete for the purpose of improving the durability of the asphalt concrete and improving the performance of the asphalt pavement. Recently, there are increasing concerns about various types of road damage due to increased traffic volume of roads and abnormal high temperatures in summer, and efforts to apply asphalt modifiers and research and development of new materials are increasing. The conventional asphalt modifier described above is applied to the production site by adding only the facility for adding the asphalt modifier without having to replace the existing asphalt concrete production equipment, while the asphalt has excellent characteristics in terms of quality as a binder for pavement. This has the advantage of being possible.

However, the conventional asphalt modifier as described above is manufactured using a new raw material, so the manufacturing cost is relatively expensive, and there is a problem in that it is a waste in terms of resource recycling.

On the other hand, in recent years, due to the rapid development of the automobile industry, the number of waste tires generated annually far exceeds 20 million, and the number is increasing more than 2 million each year. Although the waste tires are recycled products with great economic value, they are not properly recycled, and nearly half of them are left unattended or processed by simple incineration, resulting in social problems causing environmental pollution and waste of resources.

Conventional methods for modifying the properties of asphalt concrete to improve the performance of asphalt pavements will be briefly described.

Modification methods according to the prior art that can be carried out for the purpose of improving the durability of asphalt concrete, that is, plastic deformation, include a flow resistant asphalt pavement method (SMA: Stone Mastic Asphalt) and a polymer modified method (PMA: Polymer Modified Asphalt). .

Flow resistance asphalt pavement method is to improve the durability of asphalt pavement by adjusting the particle size characteristics of aggregates, and it uses a large amount of coarse aggregates, and fills between aggregates and aggregates. As a binder for bonding at the same time, asphalt and fillers are used.

However, the flow-resistant asphalt pavement method reveals a limitation in improving the durability of the asphalt only by controlling the particle size of the aggregate and the additive.

Polymer reforming method is a method of modifying the physical properties of asphalt by using a polymer. When the polymer and asphalt are mixed in an appropriate ratio, it is possible to improve crack resistance at low temperature, maintain tensile strength at high temperature, and reduce plastic deformation. At present, it is the most widely used technique for ascon reforming in theoretical or economic terms.

However, the polymer reforming method not only reveals a limitation in the development and research of the polymer, but also increases the research time and cost to secure the optimum amount of addition since the effect of the polymer does not increase infinitely according to the amount of the polymer added. This takes a disadvantage.

In the polymer modification method described above, polymers mainly used to modify the physical properties of asphalt can be broadly classified into rubber polymers and thermoplastic polymers.

As the rubber polymer, natural rubber (NR), SBS (Stylene-Butadiene-Stylene), SBR (Styrene Butadiene Rubber), waste tire rubber (crumb rubber modifier), etc. are mainly used, and thermoplastic resins include polyethylene (PE), Polypropylene (PP), ethylene vinyl acetate (EVA), polyvinyl chloride (PVC), etc. are mainly used.

However, the rubber-based polymer has a problem that the modification effect is slightly insignificant due to its miscibility with asphalt, and the thermoplastic resin-based polymer has the advantage of excellent compatibility with asphalt, but is easily decomposed by the surrounding environment, Durability and rigidity are reduced, there is a problem that can not obtain a sufficient modification effect.

Therefore, the present invention has been proposed to solve the above problems, asphalt concrete by mixing asphalt concrete powder and polyethylene powder to improve the high temperature characteristics of asphalt and waste tire rubber powder to improve the low temperature and aging characteristics Asphalt modifier and its manufacturing method and asphalt which can improve the durability and flow resistance of waste tires while improving the durability and flow resistance of the existing asphalt concrete with large change of physical properties according to the temperature by direct injection in the manufacturing process of It is an object of the present invention to provide a method for producing dry asphalt concrete using a modifier.

In order to achieve the above object, the present invention is prepared by mixing 89 to 10% by weight of asphaltene powder and 1 to 10% by weight of polyethylene powder in a rubber powder having a particle size distribution of a predetermined size. An asphalt modifier is provided.

In addition, the present invention comprises the first step of measuring the dried waste rubber rubber powder in accordance with the set blending ratio and put into the mixing device, while sifting the primary sieve through a sieve having a predetermined particle size; A second step of measuring the asphaltene powder and the polyethylene powder in the mixing device according to the mixing ratio and injecting the mixture into the mixing tank, while feeding the secondary sieve through a sieve having a predetermined particle size; And operating a mixing device to mix the waste tire rubber powder, the asphaltite powder, and the polyethylene powder, and to provide the method of manufacturing the asphalt modifier including the third step of checking the mixing state.

In addition, the present invention comprises the first step of heating and drying aggregates, such as crushed sand, crushed sand, by the sifting by particle size, and storing in the hot bin by particle size; A second step of measuring the aggregate stored in the hot bin into the mixing tank; A third step of blending with the aggregate by injecting 1/2 or less of the design amount by spraying the liquid straight asphalt into the aggregate put into the mixing tank; A fourth step of adding the waste tire rubber powder, the asphalt modifier and the asphalt powder combined with the polyethylene powder at a predetermined ratio to the mixing tank after the mixing is completed; And a fifth step of injecting and mixing the remaining straight asphalt of the input design amount into the mixing tank by spraying.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings and the test results below.

Hereinafter, with reference to the test results and the accompanying drawings will be described in detail a preferred embodiment according to the present invention.

Asphalt modifier according to the present invention and a manufacturing method thereof, and a method of manufacturing asphalt concrete with the asphalt modifier, the asphalt concrete is improved durability, high temperature / low temperature characteristics and fluid resistance to the external environment such as temperature, traffic load, etc. Implemented to improve physical properties.

Asphalt modifier according to the present invention is 10 to 80% by weight of rubber powder, which is pulverized by crushing waste tires, which are materials for recycling industrial waste materials, to a particle size of 0.4 mm or less, asphaltene powder 89 to natural hydrocarbon-based asphalt. It manufactures by mixing 10 weight% and 1-10 weight% of polyethylene powder which is a kind of chemical resin.

In the asphalt modifier composition, polyethylene powder is an additive for reinforcing the mixture of rubber powder and asphaltite powder, and is used when the on-site traffic conditions are heavy traffic or high viscosity reforming is required such as porous paving method.

Here, the waste tire rubber powder is composed of natural rubber, synthetic rubber, carbon black, other additives, etc., to reduce the aging of asphalt by heat and to the cold cracking and vehicle load caused by the brittleness of asphalt pavement at low temperatures in winter It prevents the occurrence of fatigue cracks, thereby improving the durability of the asphalt pavement.

In addition, the particle size distribution of the waste tire powder is limited to 0.4 mm or less, which is a short time between about 30 seconds to 50 seconds when the asphalt modifier added when producing asphalt concrete in a dry manner is directly mixed with the aggregate and asphalt. This is to increase the ratio of the oil and rubber components in the rubber powder to asphalt as much as possible.

In the mixing ratio of the waste tire rubber powder, the rubber modification effect can not be expected when less than 10% by weight, and when more than 80% by weight, there is a problem of deterioration of stiffness characteristics at high temperatures and difficult bonding with asphalt.

Asphalt powder is a natural asphalt of black brown solid, which is a generic name of pure asphalt, which is almost free of impurities, which has been deteriorated into asphalt over time due to petroleum infiltration of rocks, etc., to plastic deformation generated from asphalt pavement. It plays a role to improve the durability of the asphalt pavement by improving the resistance to. The asphaltite includes gilsonite, gland pitch, grahamite and the like.

Among the addition ratios of the asphaltite, when it is less than 10% by weight can not be expected to improve the plastic deformation resistance of the asphalt pavement, 89% by weight or more problems that may cause fatigue cracking or low temperature cracking of the asphalt pavement have.

The polyethylene powder is produced by dividing petroleum crude oil to separate naphtha portion (about 100-200 ° C outflow portion), decomposing it, fractionating about 25% ethylene, and polymerizing the ethylene. As a result, it plays a role of suppressing plastic deformation in summer by reinforcing high temperature characteristics of asphalt pavement.

When the polyethylene powder is added in an amount of less than 1% by weight, the effect of improving the asphalt stiffness is insignificant. If it is more than 10% by weight, economic efficiency cannot be secured due to an increase in production cost. There is a risk of causing low temperature cracking.

In the asphalt modifier applied to the product through the present invention, in order to partially compensate for the high temperature performance of the asphalt mixture, some solubility polyethylene powder was included within 10% by weight.

A method of manufacturing the asphalt modifier according to the present invention, which has been formulated at the mixing ratio as described above, will be described with reference to FIG.

1 is a schematic view showing a process flow of a method for producing a room temperature of a powdered asphalt modifier in which a rubber tire powder, asphaltite powder and polyethylene powder are mixed according to the present invention, wherein the powdered components are respectively contained within the above weight ratios. It shows a method for producing a powdery asphalt modifier through a simple process of mixing at a predetermined blending ratio.

The production equipment for this purpose is a mixing tank for accommodating the material to be mixed, a mixing device such as a screw for mixing the materials inside the mixing tank by the power provided, an input device for inputting the material, and a metering for measuring the input amount of the material. It is made of an apparatus or the like, which is the same as a conventional powder material mixing equipment, so detailed description thereof will be omitted.

Referring to Figure 1 describes a method for producing an asphalt modifier according to the present invention, the hot tire rubber powder pulverized to a particle size of 0.4mm or less hot air drying (110) at a temperature of about 40 ℃ to 60 ℃, for use In accordance with a suitable blending ratio is weighed 120 and put into the mixing tank 130 while the primary sieve 140 to discharge 0.4mm or more particles to the outside.

In addition, the asphaltite powder and the polyethylene powder are weighed according to the blending ratio, and then injected into the mixing tank 150 to make a secondary sieve 160 to discharge particles 1.0 mm or more to the outside.

The screw of the mixing device is rotated to mix (170) the waste tire rubber powder, the asphaltene powder, and the polyethylene powder (180) and check the mixing state (180). At this time, the mixing process is performed while maintaining the temperature inside the mixing apparatus at 50 ° C or less.

Maintaining the temperature inside the mixing device at 50 ° C. or lower may cause some components to dissolve when the temperature is 50 ° C. or higher, thereby consolidating in the component fraction of the asphalt modifier and thus preventing maintaining a fine powder state. This may cause a problem in that the asphalt modifier is mixed with straight asphalt in the production process of the asphalt mixture.

When the waste tire rubber powder, asphaltite powder and polyethylene powder are mixed in an even distribution through the remixing process 190 according to the degree of mixing in the mixing process of the respective powders, a powdered asphalt modifier according to the present invention is obtained. Lose.

Figure 2 is a schematic diagram showing the process flow of the asphalt concrete manufacturing method using an asphalt modifier according to the present invention, in the process of manufacturing asphalt concrete in a plant-mix method (dry method), straight asphalt and aggregate The process for producing asphalt concrete by adding the above-described asphalt modifier of the present invention according to the design blending ratio is shown.

The production equipment for this is the same as the conventional asphalt concrete manufacturing equipment of the plant mixing method, a mixing tank for accommodating the material to be mixed, a mixing device for mixing the material in the mixing tank by the power provided, and It consists of an input device, a metering device for measuring the input amount of material, a temperature sensor for detecting the temperature in the process, and a heating device capable of controlling the temperature.

As shown in FIG. 2, the method for manufacturing asphalt concrete according to the present invention is divided into granules by particle size through a hot screen 320 by heating 310 aggregates such as crushed stone and crushed sand (road construction standard specification). Aggregate particle size presented in the national standard, etc.), and stores by size in the hot bin (330) (330).

The hot bean is a device that can be stored while keeping the aggregate hot and consists of a structure that can distinguish and store the heated aggregate for each particle size.

The aggregate stored in the hot bin is metered into the mixing tank (340).

It is compounded with aggregate for 20 seconds or more so that the mixture is injected into the mixing tank into the liquid straight asphalt by injection method, or less than 1/2 of the design amount by injection 350. As soon as the blending is completed, the powdered asphalt modifier according to the present invention is added to the mixing tank 360 to be blended for 20 seconds or more. The remaining straight asphalt of the input design amount is added to the mixing tank by spraying method 370 to be blended for 20 seconds or more.

Asphalt modifier and straight asphalt introduced into the mixing device are added at a ratio of 0.5 to 6% by weight and 3 to 9% by weight based on the total weight% of the asphalt concrete.

Herein, the straight asphalt refers to straight asphalt having an penetration of 60 to 80 and an penetration of 80 to 100 according to KS M 2201, and refers to asphalt of PG 64-22 or less according to the provisions of KS F 2389.

Temperature control in the mixing tank is a very important factor in the production process of asphalt concrete according to the present invention, it is possible to maintain the temperature range of 160 ℃ to 190 ℃ from the aggregate heating to the final production.

This is because polymer materials such as rubber powder are mixed with asphalt and exhibit high viscosity physical properties. Therefore, in order to optimally form the asphalt coating on the aggregate surface, the viscosity must be lowered through temperature adjustment. For this purpose, the temperature must be maintained over 160 ℃ higher than the existing production temperature. However, at temperatures above 190 ° C., there is a risk of promoting rapid aging of asphalt, and may cause problems in asphalt plant facilities.

The method manufactured by the same manufacturing process as described above can use the existing batch asphalt plant equipment without the installation of additional equipment.

In the asphalt concrete produced by the above process, when the asphalt concrete is used in the road paving of the porous having water permeability and drainage function to pass water, the aggregate is added to the aggregate in the step of injecting the aggregate into the mixing device and aggregate. Mix.

Here, the filler is used by mixing at a ratio of 30 to 70% by weight of lime powder and 70 to 30% by weight of slaked lime powder.

In addition, the straight asphalt introduced into the mixing device is pre-injected into the storage tank of the amine (amin) -based liquid peeling prevention additives 0.2 to 0.6% by weight relative to the total weight of the straight asphalt.

In addition, if necessary to prevent the flow of asphalt during the production of asphalt concrete may be used by adding vegetable fibers.

In the case of adding the filler and the amine-based liquid peeling prevention additive to the aggregate and vegetable fibers as necessary, porous isphalt concrete can be obtained.

In addition, the vegetable fiber is to determine the mixing ratio according to the characteristics of the aggregate and asphalt and asphalt modifier for each site.

In the asphalt concrete manufacturing method of the present invention, the powdered asphalt modifier is used to improve the properties of the asphalt concrete to prevent breakage due to plastic deformation of the asphalt concrete pavement at high temperature, such as summer, It is possible to suppress the occurrence of low temperature cracking due to brittleness and fatigue cracking due to vehicle load, thereby improving durability of asphalt pavement.

Test results of the modified asphalt prepared by mixing the powdered asphalt modifier prepared according to the present invention are shown in Table 1 below. As shown in Table 1, the modified asphalt produced through the present invention was reinforced with high viscosity characteristics compared to the conventional straight asphalt, and also satisfied with the high viscosity modified asphalt standard of drainage pavement prescribed in Korea. Therefore, it is determined that the asphalt modifier produced through the present invention and the modified asphalt concrete using the same are applied to all kinds of asphalt pavements set forth in the domestic specification.

[Table 1] Quality standards of modified asphalt for drainage pavement (comparative table)

Item Quality standards Straight asphalt Modified asphalt Penetration Rate (25 ℃, 100g, 5s), 0.1mm 40 or more 73 44 Softening point, ℃ 70 or more 42 74.6 Mass change rate after thin film heating,% 0.6 or more 0.7 0.4 Permeability Residual Rate after Thin Film Heating,% 65 or more 36 25 Viscosity (60 ℃), Poise 200,000 or more 16,690 257,320  [Table 2] Common grade property results (comparative table) Common grade property Straight asphalt Modified asphalt Temperature, ℃ G * / sinδ, kPa Temperature, ℃ G * / sinδ, kPa Before aging (G * / sinδ) 52 7.018 70 5.275 58 2.773 76 2.782 64 1.149 82 1.465 Short-term aging (G * / sinδ) 52 15.410 70 8.573 58 5.840 76 4.663 64 2.338 82 2.359 BBR, S (MPa) -6 113.3103 -12 146.2383 BBR, m-value -6 0.330 -12 0.404 Common grade 64-16 82-22

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and the present invention is capable of various substitutions, modifications, and changes as road pavement materials without departing from the technical spirit of the present invention. It will be apparent to those of ordinary skill in the art. That is, it can also be used as a material for porous asphalt pavement having a permeability and drainage function requiring high viscosity modified asphalt properties.

As described above, according to the present invention, waste tire rubber powder recycled industrial waste materials and powdered asphalt modifiers in which asphaltite powders and polyethylene powders used in the chemical industry are properly mixed are used in the manufacturing process of asphalt concrete. By doing so, as well as durability and flow resistance to the external environment of the asphalt concrete, it is possible to achieve resource savings and cost savings through the use of waste materials, while improving the high temperature / low temperature characteristics, it is possible to contribute to environmental protection.

Claims (19)

delete 10 wt% to 80 wt% of rubber powder, 89 wt% to 10 wt% of asphaltene powder, 1 wt% to 10 wt% of polyethylene powder is mixed to reinforce the mixture of the rubber powder and asphaltite powder. Asphalt modifier, characterized in that prepared as. The method of claim 2, Asphalt modifier, characterized in that the rubber powder is made by processing the waste tire. The method of claim 2 or 3, Asphalt modifier, characterized in that the rubber powder is ground to a particle size of less than 0.4mm. delete A first step of introducing into the mixing apparatus at a mixing ratio of 10% by weight to 80% by weight of the waste tire rubber powder in the total weight% of the mixture constituting the asphalt modifier; A second step of introducing into the mixing apparatus at a mixing ratio of 89% to 10% by weight of asphaltene powder and 1% to 10% by weight of polyethylene powder with respect to the total weight of the mixture constituting the asphalt modifier; And A third step of operating the mixing apparatus to mix the waste tire rubber powder, the asphaltene powder, and the polyethylene powder and confirm the mixing state Method of producing an asphalt modifier comprising a. The method of claim 6, The first step is A first step of selecting waste tire rubber powder having a particle size of 0.4 mm or less through a sieving and drying the hot air at a temperature of about 40 ° C. to about 60 ° C .; And Method for producing an asphalt modifier comprising a second process of discharging the particles 0.4mm or more through the sieve to the outside when added to the mixing device. The method of claim 6, The second step is Asphalt including the process of screening only the powder having a particle size of 1.0mm or less through the sieve when the asphaltite powder and the polyethylene powder is added to the mixing device, and discharging more than 1.0 mm particles filtered out of the sieve to the outside Method of Making Modifiers. The method according to any one of claims 6 to 8, Method for producing an asphalt modifier, characterized in that for performing a mixing process in a state in which the temperature inside the mixing device is maintained at 50 ℃ or less. The method according to any one of claims 6 to 8, And a fourth step of mixing the waste tire rubber powder, the asphaltene powder, and the polyethylene powder in an even distribution through a remixing process according to the mixing degree after the third step. delete A first step of heating and drying aggregates such as crushed sand and crushed sand, and then classifying the particles by particle size and storing the particles in a hot bin by particle size; A second step of measuring the aggregate stored in the hot bin into the mixing tank; A third step of blending with the aggregate by injecting 1/2 or less of the design amount by spraying the liquid straight asphalt into the aggregate put into the mixing tank; After completion of the blending, asphalt modifying additives mixed at 10% by weight to 80% by weight of waste tire rubber powder, 89% by weight to 10% by weight of asphaltite powder, and 1% by weight to 10% by weight of polyethylene powder were added to the mixing tank. A fourth step of adding and mixing; And A fifth step of mixing the remaining straight asphalt of the input design amount into a mixing tank by spraying; Method of producing asphalt concrete comprising a. The method of claim 12, The temperature in the mixing tank is a method for producing asphalt concrete, characterized in that to maintain a temperature range of 160 ℃ ~ 190 ℃. The method according to claim 12 or 13, The second step is The method of manufacturing asphalt concrete, characterized in that it has a pitcher and drainage function to drain the water on the road surface by further mixing the filling material with the aggregate. The method of claim 14, The filler is a method for producing asphalt concrete, characterized in that consisting of a mixture of 30 to 70% by weight of lime powder and 30 to 70% by weight of slaked lime powder. The method according to claim 12 or 13,  The method for producing asphalt concrete, characterized in that the addition of 0.2 to 0.6% by weight of the amine (amin) -based liquid peeling preventive additive to the total weight of the straight asphalt added to the mixing tank in the third step. The method of claim 14, Method for producing asphalt concrete, characterized in that the vegetable fiber is further added to prevent the flow of asphalt. The method of claim 12, In the third step and the fourth step, the asphalt modifier and the straight asphalt are introduced into the mixing device at a ratio of 0.5 to 6% by weight, 3 to 9% by weight relative to the total weight of asphalt concrete, respectively. Method for producing asphalt concrete. The method of claim 12, The waste tire rubber powder is selected and added only to particles having a particle size distribution of 0.4 mm or less, and the asphaltite powder and polyethylene powder are selected and added only to particles having a particle size distribution of 1.0 mm or less. Method for producing asphalt concrete, characterized in that.

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