FR2882747A1 - ROAD COATINGS WITH REFLECTIVE PROPERTIES HAVING REINFORCED ADHESIVITY - Google Patents

Abstract

The present invention relates to a hot mix composition for road surfacing with reflective properties, comprising from 10 to 80% by weight of glass debris, and a bituminous binder, and in which: the glass debris contains at least 10% by weight of substantially reflective glass debris having at least one metallized or enamelled surface containing metal inclusions, of dimensions less than 20 mm; and the bituminous binder contains: (i) nitrogen compounds, as tackifiers; and (ii) a fluxing agent.

Description

The present invention relates to compositions for the preparation of

  road surfaces, in particular adapted to the development of traffic lanes such as roads, cycle lanes or pedestrian lanes, and having enhanced reflective properties.

  In terms of road safety, to attract the attention of a user, motorist or pedestrian, about possible dangers, or simply to guide it, it is customary to highlight certain lanes, or parts of these lanes.

  For this purpose, conventionally, it has been widely used paint lb or marking strips deposited on the surface of the roadway. In particular, paints or marking strips of a reflective nature, containing for example glass microbeads, have been widely used.

  More specifically, it has been proposed, more recently, to impart reflective properties to the pavement itself, by incorporating glass particles therein. In this context, the application EP 911 304 proposes a particularly interesting solution, which consists in incorporating into road surfaces debris of glass of which at least 10% is essentially reflective debris that has at least one metallized surface, or enamelled, either contain metallic inclusions.

  The pavement compositions of EP 911 304 have many advantages. Thus, they lead to coatings having, inter alia, very good reflective properties, which allows in particular to improve the visibility of traffic surfaces, for example when the lighting is insufficient, or in areas of risk circulation (crossroads, turns, pedestrian crossings, for example). These reflective properties can also be obtained at low cost, insofar as the glass scrap used can for example be derived from the recycling of mirrors, or metallized glasses used for example in the building industry or automotive industry.

  However, in addition to these various advantages, it has been demonstrated that, when the road coatings of EP 911 304 are bituminous coatings, they have, in the general case, adhesiveness properties which may be unsatisfactory, when they are subject to the action of traffic in the presence of water.

  By "bituminous coating" is meant here a composition adapted to the surface coating of a roadway and which comprises aggregates (including glass debris, in the case of EP 911 304 compositions) and a bituminous binder (generally a bitumen, pure or modified) ensuring cohesion between said granules. It is typically a hot mix.

  The "adhesiveness" of such a bituminous coating designates, within the meaning of the present description, the more or less pronounced ability of the bituminous binder to adhere to the aggregates by maintaining the cohesion between the aggregates when the bituminous coating is set. presence of water. This adhesiveness of the bituminous binder reflects the resistance to dissociation between the aggregates and the coating in the presence of water. Thus, in the sense used herein, the term "adhesiveness" refers to the binding force (or "affinity") existing between the binder and the aggregates in the presence of water, which some publications refer to as "Passive" adhesiveness (as opposed to so-called "active" adhesiveness which refers to the capacity initially present in the bituminous binder to bond the aggregates, that is to say, the initial properties of wetting the binder).

  For a given bituminous coating, the adhesiveness in the sense of the present description ("passive" adhesiveness) can in particular be quantified by studying the maintenance of the bonds between binder and granules after a stay in an aqueous medium, in particular by implementing the method of the XP standard T66043 ("Passive adhesion test of anhydrous binders in the presence of water") or that of the standard NF EN 12697-11 ("Test method for hot hydrocarbon mixture, part 11: determination granulate-bitumen affinity ").

  The adhesiveness of a bituminous coating can also be quantified by comparing the resistances of the coating to the compression under dry compression (resistance R) and after prolonged contact with an aqueous medium (modified resistance r), the adhesiveness being as much higher than the ratio r / R is close to 1. Such crush strength tests under compression can in particular be conducted by measuring the ratio rIR under the conditions of the DURIEZ Test, defined according to the NF standard. P 98 251-1 ("Tests relating to pavements static tests on hydrocarbon mixtures Part 1: test DURIEZ on hot hydrocarbon mixtures") or according to the test MARSHALL, as defined according to the standard NF EN 12697-34.

  The adhesive properties of the coatings of the type described in EP 911 304 are generally insufficient to maintain bonding between the aggregates and the binder, and in particular between the glass debris and the binder, when the coating is applied. in the presence of water, for example under the effect of rain. This tendency to dissociate between aggregates and bituminous binder induces in particular the following two problems: on the one hand, the reflective glass particles tend to be torn off the coating as a result of the traffic, which is likely to lead to a loss. Gloss qualities of the coating.

  on the other hand, the tendency towards separation between aggregates and bituminous binder, and in particular between the glass debris and the binder, can adversely affect the mechanical strength of the material, and it can in particular induce degradation of the pavement, in particular plumage, peeling and / or tearing.

  In order to avoid these drawbacks, it has been proposed to introduce tackifying dopes into the bituminous coating compositions of EP 911 304 to improve the affinity between aggregates and particles. Nevertheless, at present, the exact nature of the adhesiveness dopes to be used in this context has not been optimized.

  In particular, it turns out that the usual tackifiers are poorly suited in the particular case of EP 911 coating compositions 304 which are intended to provide resistance to a large traffic. Indeed, the compositions used in this context are generally compositions which comprise binders of high consistency, in particular with a view to ensuring the highest possible mechanical strength of the coating, particularly with respect to the phenomena of rutting.

  When using such binders of high consistency, the bituminous coating is generally a hot mix, which requires, both for its preparation as its subsequent application, the binder is raised to high temperatures, namely at temperatures typically at least 150 ° C., most often at least 160 ° C., or even about 170 ° C., or more.

  The implementation of such temperatures is firstly required during the hot-coating process, to ensure a sufficient fluidification of the binder, allowing a satisfactory coating of aggregates and glass particles of the coating, and in particular to wet properly and bind together the glass debris.

  On the other hand, the aforementioned temperatures must generally be maintained during the subsequent implementation of the bituminous material, namely during its application as a coating layer. Indeed, if it is used at lower temperatures, the mix is much more difficult (see impossible) to handle and apply, especially when the application is done manually.

  However, the above-mentioned temperatures induce a thermal treatment of the binder which generally degrades, at least in part, the adhesivity dopes present in the binder, which reduces their effectiveness, or may totally inhibit them if the temperatures used are too high. .

  In order to preserve the effectiveness of the adhesiveness dopes, it is therefore necessary to reduce the temperatures at which the hot mix is prepared and is used, which generally implies a loss of the mechanical qualities of the material and makes it possible besides the asphalt more difficult to handle. Indeed, to reduce the temperature of implementation of the hot coating while maintaining optimum coating qualities, it is most often necessary to use bitumen of less consistency and less mechanically resistant. Alternatively, if bitumens of high consistency are used at temperatures that preserve the adhesiveness dopes, these temperatures are generally insufficient to ensure optimum coating of the aggregates and to allow adequate application of the bitumen, which again , results in a loss of the mechanical strength of the coating.

  Thus, in bituminous coating compositions of the type of EP 911 304, the improvement of the mechanical strength properties is generally to the detriment of adhesiveness, and vice versa. As a result, the compositions of EP 911 304 are generally unsuitable for providing coatings resistant to the aggressions of a large traffic with both a good maintenance of the gloss qualities of the coating over time and a good resistance to rutting.

  An object of the present invention is to provide bituminous coating compositions which have reflective properties at least similar to that of bituminous coatings of EP 911 304, and which also have good properties both in terms of adhesiveness and mechanical resistance, allowing them to withstand heavy traffic.

  To this end, the subject of the present invention is a hot mix composition for road surfacing with reflective properties, which comprises from 10 to 80% by weight of glass debris, and a bituminous binder, and in which: glass debris containing at least 10% by weight of substantially reflective glass debris having at least one metallized or enamelled surface containing metal inclusions of dimensions less than 20 mm; and the bituminous binder contains: (i) nitrogen compounds as tackifiers; and (ii) a fluxing agent.

  In addition to the above-mentioned glass particles and binder, the composition most often contains other aggregates (mineral aggregates, sand, fillers, etc.). These additional aggregates generally represent from 10 to 90% by weight relative to the total weight of the composition of the mix, preferably at least 50% by weight, for example between 60 and 85%, and typically between 70 and 80% in mass.

  By "nitrogen compounds" is meant, in the sense of the present description, compounds, generally organic, which contain one or more nitrogen atoms, and which are present in the binder in a form available to provide the improved adhesiveness sought. These are typically amines, amino heterocycles, or mixtures of such compounds.

  The term "fluxing agent" refers to an additive which modifies the characteristics of evolution of the viscosity of the binder as a function of temperature, and which reduces: the temperature at which the binder can be used to effect a coating hot-work efficient aggregates and glass particles; and the temperature at which the mix may be applied as a surface coating layer.

  Most often, these are waxes or mixtures of waxes, which generally make it possible to lower the operating temperature by at least a few tens of degrees, for example from 20 ° C. to 40 ° C.. As used herein, a low molecular weight thermoplastic polymer, solid at room temperature, having a relatively well defined melting point and low melt viscosity. Waxes are distinguished from conventional thermoplastic polymers, which do not have such a defined melting point, but which progressively change from solid to liquid when their temperature is raised with a fairly wide transition temperature range. wherein the polymer is in a softened state between the solid state and the liquid state. The waxes, the most common of which are hydrocarbon waxes, most often have a characteristic appearance, translucent to opaque, and generally non-vitreous.

  The work of the inventors has now made it possible to establish that, if the aforementioned association of nitrogen compounds and of wax-type melting agent is introduced into the binder phase of a hot mix composition of the type of those of EP 911 304, there is both an improvement in the adhesive properties and the mechanical strength of the coating, which is particularly unexpected given the results generally observed so far.

  The improvement of the adhesiveness properties of the coating which is observed is due to the presence of nitrogen compounds, the effectiveness of which is preserved by the presence of the fluxing agent which makes it possible to conduct the hot coating at a lower temperature. than with a conventional binder not including such a fluxing agent. Thus, given the presence of the fluxing agent, the hot coating can typically be conducted at operating temperatures below 170 ° C., generally below 150 ° C., and typically of the order of 130 ° C. which makes it possible to preserve the effectiveness of the promoters of nitrogen adhesiveness of the binder.

  In this context, the presence of nitrogen compounds in the binder leads to a very clear improvement in the bonding of the glass debris with the bituminous binder, which allows a good strength of the bond between the glass particles and the binder, even when the coating layer is contacted repeatedly with water, even under heavy traffic.

  This increased bonding of the glass debris with the bituminous binder improves, in particular, the following properties of the coating: maintenance of the brightness and the effects of flickering of the coating over time; - resistance to plumage or peeling type of tearing; 20 - resistance to compression crushing.

  The joint improvement of the mechanical properties which is obtained according to the invention is particularly surprising. It turns out that the presence of the fluxing agent in the binder is not limited to inducing the above-mentioned decrease in the temperatures at which the hot coating can be carried out and the subsequent application of the coating. Unexpectedly, the presence of this fluxing agent leads in parallel to an increase in the consistency of the binder at room temperature (ie at the "service" temperature of the coating, that is to say typically between -10.degree. C and + 50 C), which results in particular in a decrease in the penetrability of the bituminous binder. On the other hand, the presence of a melting agent of the wax type generally leads to an increase in the ball / ring softening temperature. Thus, it is found, for example, that, if 3 to 5% of a melting agent of the wax type is introduced into a 50/70 penetrability bitumen and having a ball / ring softening temperature of the order of 50.degree. a modified bituminous binder of 30/40 penetrability and having a softening temperature of the order of 80 C. Thus, the presence of the fluxing agent in the binder makes it possible at the same time to preserve the effectiveness of the nitrogen compounds as adhesion promoters and to improve the mechanical properties of the coating. The improvement in the mechanical properties obtained for the coating results in particular in increased resistance to rutting.

  The bituminous coating compositions of the invention will now be described in more detail hereinafter.

  Nitrogen compounds present in the binder As nitrogen compounds particularly well adapted to improve the adhesiveness within a composition according to the invention, there may be mentioned in particular amines, alkylamidoamines, polyethylenated amines, pyrimidine derivatives , piperazine derivatives, imidoazolines, and mixtures of these compounds. Particularly interesting in this context are piperazine-1-ethanamine and its derivatives (for example reaction products of piperazine-1-ethanamine with fatty acids, for example tall oil fatty acids), alkyl - [(tetrahydropyrimidinyl) 3-propyl] (especially tallow [(tetrahydropyrimidinyl) -3 propyl]), and mixtures of alkylamidoamine and diethylene amine.

  Nitrogen compounds of this type can be introduced as such into the bituminous binder of the composition, or else in the form of compositions comprising them, such as the compositions marketed under the name of TPH by the company Chemoran, or the Cecabase L280 or Polyram L200 from Arkema. The amine compounds can then be introduced into the bitumen at the time of coating the glass debris and the bituminous binder, or they can be premixed with the bituminous binder, for example during a preliminary mixing of the bituminous binder, in particular in a tank equipped with an agitator, or continuously by injection into the supply line of the binder.

  According to another more specific embodiment, it is possible to use in the composition a hydrocarbon product (generally a bituminous binder miscible with bituminous binder, of bitumen or asphalt type) naturally containing active nitrogen compounds as promoters of adhesiveness, this product preferably having a nitrogen content of at least 1% by weight, and preferably at least 2% by weight. For this purpose, it is possible in particular to use a hydrocarbon product of the class of asphaltenites, such as, for example, Gilsonite, which generally has a nitrogen content (N) of the order of 3% by weight of nitrogen compounds. Such a hydrocarbon product, rich in active nitrogen compounds as a promoter of adhesiveness, can advantageously be introduced into the bituminous binder with a content of 1 to 10% by weight relative to the total weight of the bituminous binder. This introduction can be carried out prior to the use of the bituminous binder, or at the time of coating, for example by introducing the hydrocarbon product rich in nitrogen compounds in the coating kneader.

  Depending on the exact nature of the nitrogen compounds used as tackifiers, the content of these compounds to be used in the binder to provide optimum improvement in tack properties can vary to a very large extent.

  A quantity of nitrogen compounds which is sufficient to obtain a tackiness characterized by a ratio r / R of at least 0.8, preferably of at least 0.85, and more preferably of at least 0.9, is preferably used. the conditions of the DURIEZ test.

  The bituminous binder of the composition of the invention may contain, in addition to nitrogen compounds useful as promoters of the aforementioned type, other nitrogenous compounds referred to herein as "inactive", namely nitrogen compounds which do not play a role in the improvement of adhesiveness. Such "inactive" nitrogen compounds are in fact present in most of the usual bituminous binders, in variable proportions. The binder of the compositions of the present invention has the specificity of comprising, in addition to such inactive compounds, nitrogen compounds which are specifically active for the promotion of adhesiveness.

  Therefore, in a composition according to the invention, it is not the overall content of nitrogen compounds in the binder which is decisive, but more specifically that of the nitrogen compounds which are actually useful as adhesion improving agents. . The content of these nitrogen compounds useful as adhesion-improving agents, expressed by the amount of nitrogen provided by these compounds, relative to the total mass of the binder, is preferably at least 200 ppm of nitrogen, in general between 200 and 2000 ppm of nitrogen by weight relative to the total mass of the binder. Advantageously, this content is at least 300 ppm nitrogen, preferably at least 400 ppm nitrogen, this content typically being between 400 and 1500 ppm, more specifically between 450 and 1200 ppm nitrogen, relative to the total mass of the binder.

  In general, it is preferred that the nitrogen compound weight ratio useful as tackifier / bituminous binder (i.e., the ratio of the total mass of "active" nitrogen compounds introduced relative to the total weight of the bituminous binder) is between 0.2% and 1%, this ratio being advantageously between 0.3% and 0.8%.

  In the particular case where the nitrogen compounds active as adhesion promoters are introduced in the form of a hydrocarbon product of the family of asphaltenites such as Gilsonite (typically containing about 3% by weight of nitrogen), the ratio of the mass of the hydrocarbon product introduced to the total mass of the binder is preferably between 2 and 10%. It is generally preferred that the amount of nitrogen (N) provided by the hydrocarbon product in the binder is of the order of 600 to 3000 ppm of nitrogen, relative to the total mass of the binder.

  The fluxing agent In the context of the invention, waxes are preferably used to ensure the role of the fluxing agent. This wax preferably has a melting point greater than 85 C, as measured under the conditions of ASTM D3945 and D 3418.

  By way of example of suitable waxes, there may be mentioned hydrocarbon waxes, for example hydrocarbon waxes having a molecular weight of less than 6000 g / mol, for example between 500 and 6000 g / me. These are, for example, polyethylene waxes or polypropylene waxes. These hydrocarbon waxes preferably have a melting point of at least 85 ° C., as measured according to the aforementioned standards.

  According to a particular embodiment, these waxes are used in combination with fatty acid ester waxes, preferably having a melting point of at least 85 ° C., as measured according to the aforementioned standards. These fatty acid ester waxes are generally based on long chain carboxylic acid ester units, comprising for example at least 20, and advantageously at least 30 carbon atoms. These esters are preferably straight-chain carboxylic monoacid esters. The esters used may for example be natural esters of vegetable oils or fossil oils such as fossil waxes of lignite, but it is also possible to use synthetic esters. As waxes of fatty acid esters which are well adapted according to the invention, mention may be made of montanic acid ester waxes (acid of empirical formula C28H56O2) or of tetracosanoic acid (acid of empirical formula C24H48O2).

  The aforementioned waxes can be used alone or in combination.

  According to a particularly advantageous embodiment, a mixture of hydrocarbon waxes and fatty acid ester waxes of the abovementioned type, for example a mixture of a polyethylene or polypropylene wax, is used as a melting agent. and a fatty acid ester wax, which mixture preferably has a melting point of greater than 85 ° C. A mixture is advantageously used where the weight ratio of hydrocarbon to fatty acid wax is between 10: 90 and 90:10. According to an interesting embodiment, the mixture used in this context contains a polyethylene or polypropylene wax and a montanic acid ester wax.

  Whatever the nature of the melting agent used, its content in the binder is in general between 2% and 10% by weight relative to the total mass of the binder. This content of fluxing agent is generally less than 9%. In particular, when the melting agent is a wax or a mixture of waxes, its content is typically between 2.5 and 8%, advantageously between 3% and 5% by weight relative to the total weight of the binder.

  According to an advantageous embodiment, the binder comprises as a fluxing agent: from 0.1 to 10% by weight, preferably from 0.2 to 9% and typically from 0.2 to 5% by weight of a hydrocarbon wax, preferably a polyethylene or polypropylene wax; and from 0.1 to 10% by weight, preferably from 0.2 to 9% and typically from 0.2 to 5% by weight of a fatty acid ester wax, preferably from a wax of montanic acid ester.

  Other characteristics of the coating The compositions of the invention preferably comprise between 20% and 50% by weight of glass debris, and more preferably at least 25% of glass debris. Preferably, the glass debris present in the composition has essentially (advantageously for at least 95% by weight, and more preferably for at least 98% by mass) a size of less than or equal to 10 mm.

  In particular, in order to obtain particularly advantageous gloss characteristics, it is particularly advantageous that at least 30% by weight, and more advantageously at least 40%, of the glass debris present in the composition are substantially reflective glass debris having at least less a metallized or enamelled surface containing metal inclusions, of dimensions less than 20 mm. According to a particular embodiment, the glass debris present may consist essentially of essentially reflective glass debris of the aforementioned type. However, it is not necessary that 100% of the debris present be essentially reflective debris, to obtain coatings having good reflective properties. Thus, typically, the glass debris present in a composition according to the invention contains between 20% and 70%, for example between 30% and 50% by weight of essentially reflective glass debris of the aforementioned type, on the basis of mass. total of the glass debris present.

  For the purposes of the present description, "substantially reflective glass scrap" is understood to mean special glass scrap with essentially reflective properties as opposed to ordinary glass scrap which is transparent or translucent and for which the reflective properties are not critical. .

  The debris of special glasses used according to the invention are generally derived from glasses which have undergone a treatment, for example a metallization treatment, to exalt their reflective properties.

  Among the glasses that can be used according to the invention, mention may be made of conventional mirrors, metallized glasses and enamelled glasses. The glasses having at least one metallized surface, in particular the building glasses such as the Antélio glass, are also usable according to the invention, as well as the metal inclusion glasses such as those of the rear goggles of vehicles equipped with a metallic filament for defrost. Alternatively, one can consider the use of glass or flame lenses, or glasses for automobiles such as colored glasses "anti-glare" for glazing, or safety glasses type Securit. The glass scrap used according to the invention can come from manufacturing waste or the recovery of materials from vehicles, the demolition of buildings. It is also possible to use other types of glasses, particularly computer screen glasses, mixed with special glasses. The composition may contain mixtures of ordinary glass debris and special glass debris. The proportions of the special glass debris will be adjusted according to the reflection rate that is desired.

  The glass debris used in the composition of the invention may for example be obtained by breaking and / or crushing special glasses of the aforementioned type by any known means until debris less than 20 mm in size.

  According to one embodiment, at least 5% by weight of the glass debris present in the composition have dimensions less than or equal to 2 mm. In this case, the glass debris present in the composition may in particular comprise between 5 and 30%, for example between 10 and 20% of debris having dimensions less than or equal to 2 mm. According to a specific embodiment, the glass debris contains between 2 and 15% of debris having dimensions less than or equal to 1 mm.

  The glass debris used in the composition of the invention are preferably debris called "class 0/8", namely debris of which 80% by weight (and preferably at least 90% by weight) have dimensions of between 0 and 8 mm, with not more than 20% of the debris of dimensions between 8 and 10 mm, and essentially no particles larger than 10 mm. Particularly suitable class 0/8 glass scrap according to the invention are debris having a statistical size distribution of between 0 and 8 mm, with advantageously 5 to 25% of the glass debris between 0 and 2 mm. For example, class 0/8 glass debris containing 5 to 25% of glass debris between 0 and 2 mm, 50 to 90% of glass debris between 2 and 6 mm, and 5 to 5 mm of glass debris can be used. 25% glass debris between 6 and 8 mm. The results obtained with this particle size are particularly interesting, both in terms of gloss and adhesiveness. The hot mix compositions of the invention can be obtained by any conventional means for preparing a bituminous coating of this type. by providing for the additional incorporation of glass debris as aggregates, namely by contacting the binder in the molten state, the glass debris, usually in combination with other aggregates. These compositions can typically be made using the methods described in EP 911,304.

  To prepare a road surface from a composition according to the invention, it is preferable to conduct the hot coating at a temperature of less than 170 ° C., advantageously less than 150 ° C., or even of the order of 130 ° C., for not degrade nitrogen compounds. The presence of the fluxing agent makes it possible in this context, in spite of the low temperature used, to ensure a satisfactory coating of the aggregates as well as a good subsequent use of the asphalt during its application.

  It is possible to provide a final surface treatment of the coating or the element after its formation, intended to reveal on the surface the glass debris which previously was covered with binder. In particular, traffic can participate to this effect.

  According to another aspect, the present invention also relates to road surfaces with reflective properties which comprise a surface layer based on a composition of the aforementioned type.

  The invention also relates to the use of such a coating for the production of a traffic lane with reflective properties and adapted to withstand the aggressions of heavy traffic in an environment subject to precipitation.

  The traffic routes comprising a surface layer based on a coating obtained by using the composition of the invention have a very good mechanical strength and they are particularly resistant to rutting, including when they are subject to heavy rain or repeated rainfall. Their reflective properties are also stable over very long periods, even when they are subjected to intense traffic.

  Various aspects and advantages of the invention will become apparent from the illustrative examples set forth below.

EXAMPLES

  Three coatings R1, R2 and R3 were made using respectively the binder compositions C1, C2 and C3 defined in Table I below, where the percentages indicated are by weight relative to the total mass of the composition.

  In each case, a hot coating of a solid composition was prepared, which contains in mass: 25% of reflective glass debris (class 3/8); - 37% Noubleau aggregates (class 6/10) 35% Noubleau sand (class 0/2) 3% limestone filler The coating of the aggregates was carried out by mixing the glass debris and aggregates. using 5.5 parts by weight of binder composition (Cl, C2 or C3) in the molten state, per 100 parts by weight of solid composition.

  The temperatures of implementation of the hot coating and the application of the coating to form the coatings R1, R2 and R3 are reported in Table L Table I: compositions C3 to C3 and temperature of implementation of hot coating Composition Cl C2 C3 Hydrocarbon binder (1) 100% 99,5% 95,5% Promoter nitrogen adhesivity (2) - 0,5% 0,5% Fluxing agent (3) - - 4% Working temperature 160 C 160 C 130 C (1): penetration bitumen 50/70 (2): Cecabase 260 (3): 3% hydrocarbon wax + 1% acid ester wax The adhesiveness properties and the mechanical properties of the coatings R1, R2 and R3 thus obtained are reported in Table II below.

  Table II: properties of coatings R1 to R3 Coating R1 R2 R3 test HARD 9,3 10,3 9,4 resistance to dry crushing 7.3 9,1 8,6 (R) 0,78 0,88 0 , 91 resistance to crushing after standing in water (r) R / R ratio Mechanical properties 19.78 13.5 Rutting depth (*) (*) measured according to standard NF P 98-253-1 at 60 C 10000 cycles.

Claims (16)

  1. Hot mix asphalt composition for road surfacing with reflective properties, comprising 10 to 80% by weight of glass debris, and a bituminous binder, and wherein: - the glass debris contains at least 10% by weight substantially reflective glass debris having at least one metallized or enamelled surface containing metal inclusions, less than 20 mm in size; and the bituminous binder contains: (i) nitrogen compounds, as tackifiers; and (ii) a fluxing agent.   2. Composition according to Claim 1, in which the nitrogen compounds present as tackifying agent (s) are chosen from amines, alkylamido amines, polyethylene amines, pyrimidine derivatives and piperazine derivatives. , imidazolines and mixtures of these compounds.   A composition according to claim 1 or claim 2 wherein the bituminous binder used comprises a hydrocarbon product naturally containing nitrogen compounds useful as tackifiers, for example a hydrocarbon product of the asphaltite family. .   4. Composition according to claim 3, wherein the ratio of the mass of the hydrocarbon product introduced to the total mass of the binder is between 2 and 10%.   5. Composition according to any one of the preceding claims, wherein the content of nitrogen compounds useful as tackifying agents, expressed by the amount of nitrogen provided by these compounds, relative to the total mass of the binder, is at least 200 ppm nitrogen, by weight relative to the total mass of the binder.   6. Composition according to one of the preceding claims wherein the nitrogen compounds weight ratio useful as tackifying agents / bituminous binder is between 0.2% and 1%.   7. Composition according to one of the preceding claims wherein the content of fluxing agent is between 2 and 10% by weight relative to the total mass of the binder.   8. Composition according to any one of the preceding claims, wherein the fluxing agent used is a wax.   9. Composition according to claim 8, wherein the wax has a melting point greater than 85 C.   The composition of claim 8 or claim 9, wherein the fluxing agent is a hydrocarbon wax, a fatty acid ester wax, or a mixture of such waxes.   The composition of claim 10, wherein the fluxing agent used is a mixture of a hydrocarbon wax and a fatty acid ester wax.   12. Composition according to any one of claims 8 to 11 wherein the content of fluxing agent in the binder is between 3 and 5% by weight relative to the total mass of the binder.   A composition according to any one of the preceding claims, wherein the binder comprises, as a fluxing agent, from 0.1 to 10% by weight of a hydrocarbon wax, and from 0.1 to 10% in bulk of a fatty acid ester wax.   A composition according to any one of the preceding claims, wherein at least 30% by weight of the glass debris present is substantially reflective glass debris having at least one metallized or enamelled surface containing metal inclusions of dimensions less than 20. mm.   15. A road surface with reflective properties comprising a surface layer based on a composition according to one of claims 1 to 14.   16. Use of a coating according to claim 15 for the realization of a traffic lane with reflective properties and adapted to heavy traffic in an environment subject to precipitation.