CZ20022334A3 - Bituminous coated material for hot laying and containing rubber, process for producing such coated material and making roads from this coated material - Google Patents

Abstract

The inventive hot-setting bitumen-coated material is used for forming the top layer of a road and comprises a granular mixture with varying granulometry and a bonding agent in the form of a conventional bitumen or a modified bitumen. Said granular mixture contains chips, a sandy fraction and powdered rubber, said sandy fraction having a lower volume than the interstitial volume of the chips. According to the invention, the particles of powdered rubber are less than 1.5 mm in size and the percentage of rubber in the granular mixture is less than 1.5 %.

Description

A thermally deposited bituminous encapsulated material containing rubber, a process for the manufacture of said encapsulated material, and a method of making pavements from said encapsulated material

Technical field

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermally deposited rubber coating material for road construction. The invention also relates to a process for the production of this bituminous coated material and to a method of making pavements from the coated material.

BACKGROUND OF THE INVENTION

For many years, road coatings have been made of coated materials containing reclaimed rubber. An example is known from EP-A 0 672 791.

• Adding rubber to the resins allows improved properties of the coated materials, provides increased flexibility to the coatings formed, improves their resistance to fats and low temperatures, and reduces noise and reflection of light sources. The use of reclaimed rubber also contributes to the disposal of used tires of different origin.

Therefore, processes have been developed in which the rubber is mixed with the resin to form aggregates.

Granules having a size range of 1 to 3 or 2 to 4 mm, i. rubber granules comparable to that of gravel (see, for example, U.S. Patent 5,548,962).

The formed road coat then exhibits, at least in some places, a thickness of rubber several millimeters between traditional granules or gravel. Because the rubber has an extremely low modulus, such, the thickness of the rubber between traditional granules made of hard materials leads to significant coating deformation when subjected to high local stresses caused by truck traffic, and these significant coating deformation leads to rapid degradation of the rubber.

To overcome this problem, the part of the sand fraction that usually accompanies gravel is replaced by powdered rubber, the particles of which have an average diameter of 0 to 1.5 mm. The granules thus formed! The bituminous binder, which may be a pure bitumen or a bitumen modified with additives, often polymers, is then added to the scaffold.

The latter technique is in principle satisfactory. However, further improvement of road resistance is sought, for example, for applications in parking areas where maneuvering is frequent, with very small turning radii. In addition, the rubber is sensitive to moisture, which sometimes causes numerous disadvantages.

SUMMARY OF THE INVENTION

SUMMARY OF THE INVENTION It is an object of the invention to provide a thermally deposited bituminous coating material containing rubber which does not have the above-mentioned disadvantages.

The bituminous coating material should also allow to obtain a road surface with good water drainage capacity and good sound properties.

This object is achieved by a hot-rolled bituminous coating material intended for the production of pavements comprising a granular mixture with a discontinuous particle size distribution and, as a binder, bitumen. The granular mixture comprises gravel, sand fraction and powdered rubber, the sand fraction and powdered

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The rubber together has a smaller volume than the volume of the gravel gaps.

According to the invention, the particle size of the rubber powder is less than 1.5 mm and the rubber content in the granular mixture is less than 1.5% by weight.

To achieve good roughness, the total sand content (mineral sand and powdered rubber) should not exceed the volume of the gravel gaps, i.e. approximately 30 to 40% of the total volume. Thus, the powdered rubber is used at the expense of the sand fraction, not in addition to the usual sand fraction.

The invention also relates to the following features, considered individually or in any technically possible combination:

The binder of the anchor layer may be a pure resin, also called a conventional resin, or a modified resin, and in particular a pure resin emulsion or a polymer modified resin emulsion. Elastomer emulsions may also be used, but not necessarily, for their chemical affinity to rubber.

The particle size distribution of the rubber is chosen, similarly to the finest sand, 0/1 mm (90% of the particles have a size less than 1.0 mm, i.e. the rest of the rubber particles on nets with a mesh size of 1 mm is less than 10% ). This option permits the replacement of a portion of the sand constituting the granular resin bitumen by rubber while providing the desired characteristics of the coated material.

The rubber content of the granular composition is in the range of 0.5 to 1%.

The granular composition contains, in addition to the sand fraction, gravel and rubber, a proportion of the rock dust (preferably limestone) of at least 1.5% of the total weight of the granulate.

This rock dust, also called a filler, is characterized by 90% of its weight passing through a sieve

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with a mesh size of 80 μπι.

The particle size distribution of the granular mixture is determined by calculating the volume fractions of the granular mixture.

In practice, the considerable difference in density of the various components of the granular mixture, i.e. gravel, sand fraction and rubber, has to be taken into account.

The volume fraction Vi of each component and of the granular mixture is calculated according to the following equation:

νί = 100Ρί / ρίΣί (Pi / pi) where P1 is the mass fraction of component i,

Pi is the actual density of component i.

The particle size distribution of the granular mixture is calculated according to the following equation:

Bj = (Σι (Aij. Ví)) / 100 where Bj is the subnetwork of the mixture in percent by volume passed through the sieve j,

Aij is the undersized fraction of the component i in weight percent passed through the sieve j.

The L content of the bituminous component, i.e. the weight fraction of the bituminous component and the total weight of the coated material, is calculated from the modulus K of the binder content, the conventional specific surface area Σ and the coefficient.

L = Ka ⁵ ^ t- 4 · 4 · 4 ··· 4 · where K is a value between 3.5 and 4 , 5 and is 2.65 / pi

Σ is defined by 100Σ = 0,25G + 2,3S + 12s + 135f + 450KU with weight ratios

G particles larger than 6.3 mm

S particle size from 6.3 to 0.315 mm with particle size from 0.315 to 0.08 mm f particles smaller than 0.08 mm

KU rubber particles.

The KU weight ratio reflects the specific absorbency of the rubber relative to the limestone filler: while the absorbency of the limestone filler is 50 g (net weight for 15 g of resin), the same absorbency of 15 g of rubber has the same. Thus, rubber absorbs 50/15 = 3.33 times more resin than filler.

The binder content module is preferably 3.8 to 4.2.

The resin content is preferably 4 to 14 wt.

Tables I and II show two calculation results, i.e. two reconstructions of the bituminous coating compositions of the invention with gravel having a particle size distribution of 0/10 and containing 1% and 1% respectively. 1.5% rubber.

Rubber is a porous material and moisture adheres deep into its structure as soon as its content becomes significant. The natural moisture content of the rubber after manufacture is low, generally less than 0.5%. This amount is acceptable for the production of the sound-absorbing coated material, it should not exceed 1% by weight.

In particular, the rubber becomes wet during storage, on-site material during packaging, transport, and especially during the storage of its coated production, it is difficult to protect the rubber bags. The result is then an increase in its humidity in the case

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The addition of a certain amount of bitumen to the rubber, approximately 1 to 15% of its weight, has been found to greatly limit the ability of the rubber to absorb water in depth. The presence of bitumen around the rubber particles makes them water resistant.

Improvement of the properties of the powdered rubber can be easily achieved by pretreating the powdered rubber, i.e. by spraying the resin onto the powdered rubber at the end of the production line. It is sufficient to pass the freshly made powdered rubber through a chamber where the resin is sprayed (micronized) at a temperature of about 150 ° C.

The moisture content is measured by an oven drying method according to NF P 94 050.

The rubber powder thus treated is then used in a conventional manner. The amount of bitumen already integrated into the powdered rubber should be considered and corrected for the amount of bitumen in the coating material composition.

The behavior of coated material on the road in the presence of water must be verified. A methodology for verifying the mechanical behavior of the mixture in the presence of water is in place. This methodology consists of two subtests:

(a) A classical Duriez test requiring a dip / compression value greater than 0.85, preferably greater than 0.90, a value greater than 0.75 or 0.80 being considered sufficient for conventional coated materials.

b) Wear test (Cantabro method introduced in Spain materials), modified in that Angeles, were increased from 300 maintained to 18 ° C.

loss of test (Spanish standard NLT 352/86, for drained coated drum speed, called "Los 500," and the temperature was the weight of the material at

Under these conditions, the sample to be coated must be 7 j · *

Less than 10% of the original weight of the coated material.

The coated material is applied as a thin carpet to the pavement, the layer thickness being 1.5 to 4 cm, preferably 2.0 to 3.0 cm for a 0/6 particle size distribution, and 2.5 to 3.5 cm for a distribution particle size 0/10.

The invention also relates to a process for the production of hot-laid bituminous coating material for the production of pavements comprising a granular composition with a discontinuous particle size distribution and, as a binder, a conventional resin or modified resin, the granular composition comprising gravel, sand fraction and powdered rubber. the method comprising the step of bringing the gravel and sand fraction to the coating temperature and mixing them with a binder to form a bituminous coating material.

According to the invention, the powdered rubber is added in an amount of less than 1.5% by volume of the granular mixture, the particle size of the powdered rubber being less than 1.5 mm.

Since the rubber is sensitive to very high temperatures, especially in the presence of a flame, it is introduced at the site of the production line where the granulate has already reached the desired coating temperature.

In addition, in any process for the production of bituminous coating material, the small particle size and the resulting low weight must be considered when adding the rubber. For both of these properties, the rubber is a material that can be entrained by the air stream during the drying process. To compensate for these disadvantages, the rubber is introduced immediately before the end of the gravel and sand fraction drying zone.

The invention also relates to the following features, considered individually or in any technically possible combination:

In the case of the production of coated material by means of a discontinuous device, the regenerated rubber is introduced into «· • • • •φφφφφφφφφφφφφφ φφφφφφφφφφφφφφφφφφφφφφφφ>>>>>> · mixers in heat-melt bags continuously at the bottom of the hot conveyor.

In the case of the production of coated material by means of a continuous device connected to a dosing hopper, which allows the granulate to be fed to the bottom of the hot conveyor, this hopper is used.

In the case of the production of coated material by means of a continuous device with a separate mixer, the regenerated rubber is fed into the mixer at the bottom of the hot conveyor at the end of the drying process.

- In the case of the production of the coated material by means of a continuous device with a mixing device integrated with the drying drum, a dosing hopper is necessary to allow the introduction of rubber at the end of the mineral particles drying process in the recycling circuit. If this is not possible, a screw or pneumatic conveyor is used.

Two alternatives are possible to ensure that the moisture content of the powdered rubber does not exceed 1% by weight. According to a first alternative, the moisture content of the rubber is measured before it is added to the mixer to the mixture of gravel and sand fraction, and if necessary, the moisture content is measured. adjusts. According to a second alternative, the above-described micronized rubber is used.

The invention further relates to a method of making a pavement from the bituminous coated material described above.

According to the invention, the method comprises the following steps: laying an anchoring layer on the road to be covered with a carpet, laying one layer of said bituminous coating material and compacting the bituminous coating layer.

According to a preferred embodiment of the invention, the laid bituminous wrapped material is compacted by a device other than a wheeled material.

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99Λ 9999 · 9 9999 tt 99 compactor. The wrapped material must not adhere to the working surfaces of the compactor.

Further features and advantages of the invention are illustrated by the description of two embodiments of the coated material according to the invention and by one embodiment of the method for producing the bituminous coated material according to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The process according to the invention is described with the aid of a single drawing showing a tumble dryer-mixer and elements necessary for introducing the rubber.

DETAILED DESCRIPTION OF THE INVENTION

As is already apparent from Tables I and II mentioned above, the bituminous coating material according to the invention comprises predominantly gravel of various sizes, supplemented with sand fraction, powdered rubber and bitumen. Tables III and IV represent two additional examples of compositions. The first example is a bituminous coated material containing 1% rubber, referred to as coated material A, while the second example is a bituminous coated material containing 2% rubber, referred to as coated material B.

The coated material A comprises a granular composition consisting of 95.5% mineral granular material of which 78.5% has a 6/10 particle size distribution, while 17% has a 0/2 particle size distribution, and 1% a rubber with a 0 particle size distribution / 1. The rest (3.5%) is the filler.

A modified bitumen is added to this mixture of granular material and rubber. Its content is 6, 6% by weight of dry granular material.

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The bituminous coated material B differs from the coated material A in the content of various components. The mixture of granular material and rubber comprises 83% mineral granulate with a 6/10 particle size distribution and 12% mineral granulate with a 0/2 particle size distribution. The rubber content with a particle size distribution of 0/1 is 2% and the filler content is 3%. The resin content is 6.6%.

Coated material A resp. B is produced at 165 ° C resp. 150 [deg.] C.

To illustrate the discontinuity of the particle size distribution of the mixture of granular materials used to produce the bituminous coated materials of the invention for manufacture, Table IV contains the particle size distribution according to standard P 18-560 of mineral granules 6/10 and 0/2. Table IV further contains the numerical values of the above coefficients, i.e. the specific surface area Σ, the modulus of binder content K, the theoretical density of the granular material and the actual density Vi of the granular material.

The advantages of the bituminous coating materials of the invention are verified by carrying out conventional tests.

The results of these tests are shown in Table IV. These results show the compaction and compressive strength and air and water behavior of the coated materials A and B.

Particular tests, such as the CANTABRO test, allowing determination of the weight loss of the stressed test specimen, and creep / relaxation tests were performed on coated A material.

The CANTABRO test practically consists of shaping cylindrical specimens weighing approximately 1300 g, and then using them at a selected temperature of 18 ° C in a Los Angeles rotary drum. After the wear test, the weight loss of each specimen is measured. Results • · · * 4 4 «·« ·.

The table IV shows better properties of the bituminous coating material of the invention than other bituminous coating materials used previously.

Furthermore, noise measurements were carried out on various test sections corresponding to city streets and intercity roads.

The method used is to compare two coatings with one another. For example, the original road coating and the new coating according to the invention, or different coatings on the same road, are compared. These measurements were carried out by a near-field measurement method consisting of measuring the noise generated by a moving light vehicle using a built-in microphone located near the wheel, away from the noise produced by the engine and the exhaust.

Thus, other noise sources below are ignored when measuring driving noise (produced noise reduced by sound absorbed). This procedure makes it possible to characterize the coating, even in urban areas, independently of its surroundings.

This test was developed in the Laboratoire Régional de l'Est Parisien, where measurements were also taken, the results of which are given below.

The city has a reference speed of 50 km / h. Three sections were measured. The results are as follows:

Noise level 1 m from the wheel at 50 km / h Construction site Original cover Roadway according to the invention Improvement 1 90.20 dBA 83.5 dBA 6.7 2 88.56 dBA 83.58 dBA 4.98 3 90.14 dBA 83.52 dBA 6, 62

The improvement is considerably greater than 4 dBA, which corresponds to a noise reduction of more than 70%.

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On the section of road II. A grade 0/10 of conventional bituminous concrete was applied. However, the section passing through the village was treated with the coated material of the invention.

Measurements on this type of test road were performed at a speed of 90 km / h.

Cover Noise level 1 m from the wheel at 90 km / h Improvement breaded material Coated material according to the invention 93.6 dBA New bituminous concrete 96.5 dBA 2.9 dBA Older bituminous concrete 98.1 dBA 4.5 dBA

The coated material according to the invention allows an improvement of more than 4 dBA over the older coating and 3 dBA over the new 0/10 bituminous concrete.

The production of the bituminous coated material according to the invention can be carried out in a discontinuous plant or alternatively in a continuous plant using a drum dryer-mixer, according to the example shown in the drawing.

In the apparatus associated with the tumble dryer-mixer, the bituminous coated material according to the invention is obtained in the following steps: dosing granular materials, adjusting by adding binder, drying these materials, dosing bitumen and adding bitumen to granulates, adding rubber powder, mixing all these materials and dedusting the obtained bituminous coated material.

In the drum dryer-mixer 1, the gravel / filler mixture is dried and then mixed with the binder resin and the hopper rubber 2. The rubber and resin are preferably added to the mixture by means of two lancets 3,4 whose outlet nozzles are arranged prior to recycling ring 5, all the components of the bitumen coated and mixed with the material.

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TABLE I

Recomposition according to identification Example: Coated materials 0/10, with 1% rubber Formulation Composition 6/10 NOUBLEAU 79% Specific surface area: 13.763 cm / g Module content binders: 3,894 0/2 NOU BLEAU 17% Theoretical density: 2.554 g / cm Filler PIKETTY 3% M.V.R. aggregates 2.812 cm ³ / g Rubber 0/1 1% Binder COLFLEX N 6.20% Coating temperature 170 [deg.] C Weight distribution veli particle size (NF P 18-560) Sifter # Podsítné 6/10 0/2 Filler Rubber 0 (%) NOUBLEAU NOUBLEAU PIKETTY 20 May 100.0 100.0 100.0 100.0 100.0 14 100.0 100.0 100.0 100.0 100.0 12.5 100.0 100.0 100.0 100.0 100.0 10 90.0 87.4 100.0 100.0 100.0 8 56.5 44.9 100.0 100.0 100.0 6.3 29.7 11.0 100.0 100.0 100.0 4 21.9 1,2 100.0 100.0 100.0 2 20.3 0.8 92.4 100.0 100.0 1 16.1 0.7 67.8 100.0 99.9 0.5 11.5 0.7 43.3 100.0 61.1 0.315 9.7 0.6 34.8 100.0 26.6 0.2 8.1 0.6 26.4 100.0 9.6 0.08 6.1 0.6 17.0 90.0 0.7 M.V.R. G 2,812 2,856 1,000 2,820 2,700 1,000 1,000 Volume dis particle size tribution NF 18-560 Volume share 77.26 16.84 3.10 2.79 G (%) Sifter# Podsítné 6/10 0/2 Filler Rubber 0 (%) NOUBLEAU NOUBLEAU PIKETTY 20 May 100.0 100.0 100.0 100.0 100.0 14 100.0 100.0 100.0 100.0 100.0 12.5 100.0 100.0 100.0 100.0 100.0 10 90.3 87.4 100.0 100.0 100.0 8 57.4 44.9 100.0 100.0 100.0 6.3 31.2 11.0 100.0 100.0 100.0 4 23.4 1,2 100.0 100.0 100.0 2 22.1 0.8 92.4 100.0 100.0 1 17.9 0.7 67.8 100.0 99.9 0.5 12.6 0.7 43.3 100.0 61.1 0.315 10.2 0.6 34.8 100.0 26.6 0.2 8.3 0.6 26.4 100.0 9.6 0.08 6.1 0.6 17.0 90.0 0.7 M.V.R. G 2,812 2,856 1,000 2,820 2,700 1,000 1,313 Resin fraction by volume = 16,81%

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TABLE II

Recomposition according to identification Example: Coated materials 0/10, with 1.5% rubber Formulation Composition 6/10 NOUBLEAU 79% Specific surface area: 15.428 cm / g Module content binders: 3,969 0/2 NOUBLEAU 17% Theoretical density: 2.532 g / cm Filler PIKETTY 2.5% M.V.R. aggregates 2.797 cm ³ / g Rubber 0/1 1.5% Binder COLFLEX N 6,50% Coating temperature 170 [deg.] C Mass distribution command particle bones (NF P 18-560) Sifter # Podsítné 6/10 0/2 Filler Rubber 0 (%) NOUBLEAU NOUBLEAU PIKETTY 20 May 100.0 100.0 100.0 100.0 100.0 14 100.0 100.0 100.0 100.0 100.0 12.5 100.0 100.0 100.0 100.0 100.0 10 90.0 87.4 100.0 100.0 100.0 8 56.5 44.9 100.0 100.0 100.0 6.3 29.7 11.0 100.0 100.0 100.0 4 21.9 1,2 100.0 100.0 100.0 2 20.3 0.8 92.4 100.0 100.0 1 16.1 0.7 67.8 100.0 99.9 0.5 11.3 0.7 43.3 100.0 61.1 0.315 9.3 0.6 34.8 100.0 26.6 0.2 7.6 0.6 26.4 100.0 9.6 0.08 5.6 0.6 17.0. 90.0 0.7 M.V.R. G 2,797 2,856 1,000 2,820 2,700 1,000 1,000 Volume dis particle size tribution (NF P 18-560) Volume share 76.59 16.69 2.56 4.15 G (%) Sifter # Podsítné 6/10 0/2 Filler Rubber 0 (%) NOUBLEAU NOUBLEAU PIKETTY 20 May 100.0 100.0 100.0 100.0 100.0 14 100.0 100.0 100.0 100.0 100, Q 12.5 100.0 ^; 100.0 100.0 100.0 100.0 10 90.3 87.4 100.0 100.0 100.0 8 57.8 44.9 100.0 100.0 100.0 6.3 31.8 11.0 100.0 100.0 100.0 4 24.3 1,2 100.0 100.0 100.0 2 22.8 0.8 92.4 100.0 100.0 1 18.6 0.7 67.8 100,0: 99.9 0.5 12.9 0.7 43.3 100.0 61.1 0.315 9.9 0.6 34.8 100.0 26.6 0.2 7.8 0.6 26.4 100.0 9.6 0.08 5.6 0.6 17.0 90.0 0.7 M.V.R. G 2,797 2,856 1,000 2,820 2,700 1,000 1,313 Resin fraction by volume = 17,47%

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TABLE III

Comparison of two coated materials according to the invention with 1 and 2% KU

Grained material % KU % binders r / R TO Quartzite Brix 2 6, 6 0.84 3, 669 Quartzite Brix 1 6, 6 0.97 3.88 Quartzite Meilleraie 2 6.1 0.79 3.7 Quartzite Meilleraie 1 6.1 0.87 3,868 Diorit Noubleau 2 6, 5 0.86 3,861 Diorit Noubleau 1 6.2 0.93 3, 894 Vaubadon sandstone 2 6.3 0.77 3, 6 Vaubadon sandstone 1 6.4 0.87 3,837 Quartzite Vignats 2 6.6 0, 84 3, 61 Quartzite Vignats 1 6.6 0.94 3,819 Porphyry Voutré 2 7 0.8 3,865 Porphyry Voutré 1.5 6.9 0.83 3,881 Porphyry Voutré 1,2 7 0.88 4,035

KU = rubber powder r / R = reduction coefficient in the Duriez test

K = modulus of binder content calculated by the process according to the invention φφ φφ ··· ·

TABLE IV φ ΦΦΦ φ φ φ · · · · • • • • • • • • · · · · φ φ φ φ φ φ φ

IAL bituminous coated material Bituminous Coated Material (B) Composition 6/10 Brix 78.5% 83.0% 0/2 Brix 12.0% 0/2 Brix 17.0% filler 3.5% 3.0% rubber 0/1 1.0% 2.0% resins 60/70 6.60% 6.60%

DURIEZ (*) hydrostatic density 2.263 g / cm @ ³ 2.044 g / cm <^6> compactness 94.5% 86.2% Rc (R) water 9,2 MPa 5.9 MPa Rc (r) air 8.9 MPa 4,9 MPa reduction coefficient r / R 0.97 0.84 absorbed water 1.5% 3.8%

CANTABRO (**) geol. compactness 89.1% hydro, compactness 93.7% wear% 9.3%

(*) Duriez-LCPC simple pressure test according to NF P98-251-1 (**) CANTABRO test according to Spanish standard NLT 352/86 ····

- * 18 ^;

TABLE IV (continued)

sieve (mm) Bituminous coated material (AND) Bituminous coated material (B) 20 May 100.0 100.0 14 100.0 100.0 12.5 100.0 100.0 10 93.6 92.5 8 56.9 51.9 6.3 29.5 24.0 4 22.7 18.1 2 19.6 16.0 1 15.4 13.1 0.5 11.8 9.8 0.315 9.6 7.8 0.2 8.1 6.6 0.08 5.9 5.3

Β · ··· Β

Claims (9)

PATENT CLAIMS A thermally deposited bituminous coating material for the manufacture of pavements, comprising a granular composition with a discontinuous particle size distribution and, as a binder, a bitumen, the granular composition comprising as components (i) gravel, sand fraction and powdered rubber, the rubber content in the granular mixture it is less than 1.5% by weight, and wherein the sand fraction and the powdered rubber together have a smaller volume than the volume of the gravel gaps, characterized in that the particle size of the powdered rubber is less than 1.5 mm. The coated material of claim 1, wherein the particle size of the powdered rubber is less than 1 mm for 90% of the particles. A coated material according to claim 1, characterized in that the content of powdered rubber in the granular material is 0.5 to 1. %. The coated material according to any one of claims 1 to 3, characterized in that the particle size distribution of the granular mixture is calculated according to the equation: B _j = (Z _i (A _ij .In _i)) / 100 where Bj is the proportion of undersize mixture in volume percent passes through a sieve j Aij is the undersized fraction of the component i in percent by weight passed through the sieve j, Vi is the volume fraction of component i. Coated material according to one of Claims 1 to 4, characterized in that the L content of the bitumen component in total 44 444 «44 44 44 4 44 4444 4 4 4,444,444 4,444 4 4 4 4 4 44 444 4444 <20 · - ··· ·· ·· ** ·· ** The weight of the coated material is calculated according to the equation L = K.oe. -Vz ⁵ wherein K is a modulus of binder content with a value in the range 3.5 to 4.5, and is a coefficient for correcting the actual density V 1 of the component and, and Σ is the conventional surface area Ingredients i , where Σ is defined by 100 Σ = 0.25 G + 2.3 S + 12 sec + 135 f + 450 KU with weight ratios G particles larger than 6.3 mm WITH Particles from 6.3 to 0 315 mm with particle size from 0.315 to 0,08 mm F particles of less than 0.08 mm KU of rubber particles. 6. The coated material according to Claim 5 characterized team that the module of binder content K has value in range 3.8 to 4.2 A process for the production of a thermosetting bituminous coating material for the manufacture of pavements comprising a granular mixture with a discontinuous particle size distribution and a bitumen as a binder, the granular mixture comprising gravel, sand fraction and powdered rubber, the method comprising the steps of introducing gravel and sand fractions to the coating temperature and mixing them with a binder to form a bituminous coating material, characterized in that the powdered rubber is added in an amount of less than 1.5% by volume of the granular composition, the particle size of the powdered rubber being less than 1.5 mm. The method of claim 7, wherein the rubber powder is pretreated with the resin micronization, and the amount of resin added during mixing is corrected for that amount. aa · «« · · ♦ · aa ♦ * aa a · a · a * a a · · a a a a a a a a a · a a a a a a a a a a a a Method according to claim 7 or 8, characterized in that the moisture content is measured before the addition of the powdered rubber to the mixture of gravel and sand fraction, whereupon it is adjusted if necessary to not exceed 1% by weight. A method of making a pavement of bituminous coating material according to any one of claims 1 to 6, obtained by a method according to any one of claims 7 to 9, comprising laying an anchoring layer on the road to be covered by the carpet, laying one layer of said bituminous coating material and compacting. of this bituminous coating layer.