Anti-rutting dry process sbs asphalt mixture and preparation method thereof

Abstract

The application discloses an anti-rutting dry-process SBS asphalt mixture and a preparation method thereof, and belongs to the technical field of asphalt mixture engineering materials. The anti-rutting dry-process SBS asphalt mixture comprises 80-90 parts of aggregate, 6-8 parts of dry-process SBS modified asphalt, 1-2 parts of modifier and 5-6 parts of mineral powder. The modifier comprises 80-85% rock asphalt, 3-5% SiC particles, 5-7% quartz sand and 6-8% silane coupling agent. The dry-process SBS modified asphalt comprises 90-96% asphalt, 3-5% dry-process SBS particles, 0.3-0.4% sulfur, 0.5-1% zinc stearate, 0.3-0.5% antioxidant and 0.8-1% naphthenic oil. The application further discloses a preparation method of the anti-rutting dry-process SBS asphalt mixture. The anti-rutting dry-process SBS asphalt mixture and the preparation method thereof can solve the problem of poor anti-rutting performance of the existing asphalt mixture and improve the low-temperature stability of the asphalt mixture.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of asphalt mixture engineering materials, and particularly relates to a dry-process SBS asphalt mixture with anti-rutting performance and a preparation method thereof. BACKGROUND

[0002] In the field of road construction, with the continuous growth of traffic volume and the increasing number of heavy vehicles, the anti-rutting performance of the road surface becomes a key factor affecting the service life of the road and the driving safety. The conventional ordinary asphalt pavement is prone to rutting under high temperature and heavy load conditions, which greatly reduces the flatness and use performance of the road and increases the maintenance cost.

[0003] Ordinary asphalt is a temperature-sensitive material, and its performance is extremely sensitive to temperature changes. Under high-temperature environment, the viscosity of asphalt is significantly reduced, the anti-deformation ability is weakened, and it is difficult to withstand the repeated action of vehicle load, resulting in permanent deformation of the road surface and formation of ruts. To solve this problem, people have begun to study and use various modified asphalt technologies to improve the performance of asphalt pavement, among which SBS modified asphalt technology has been widely used.

[0004] SBS (styrene-butadiene-styrene block copolymer) is a thermoplastic elastomer with excellent performance. The introduction of SBS into asphalt can form a physical or chemical cross-linking network structure in the asphalt system. In the prior art, wet-process SBS modified asphalt is more common, that is, SBS is first dissolved in an organic solvent, and then mixed and stirred with asphalt. However, the wet-process has many shortcomings, such as the use of organic solvents not only increases the production cost, but also causes environmental pollution and safety hazards; the production process is relatively complex, and special equipment and process conditions are needed to control the dissolution and mixing process of SBS; the product storage stability is poor, and SBS and asphalt are prone to phase separation during storage, which affects the performance of the modified asphalt.

[0005] In comparison, dry-process SBS modified asphalt technology has gradually attracted attention. The dry-process is to directly mix and stir SBS particles with asphalt, additives, etc. at high temperature without using organic solvents. Although the dry-process SBS modified asphalt overcomes some shortcomings of the wet-process to some extent, there are still some technical problems. For example, SBS particles are difficult to achieve uniform dispersion in asphalt, resulting in poor modification effect, which cannot fully play the role of SBS in improving the performance of asphalt, and the improvement degree of anti-rutting performance is limited.

[0006] The existing patent CN202310095442.8 discloses a dry SBS modifier, SBS modified asphalt and a preparation method thereof. The dry SBS modifier comprises the following components in parts by weight: SBS polymer modifier 20-40 parts, polyethylene 20-40 parts, octabromoether 10-15 parts, polyethylene wax 5-15 parts, solubilizer 5-15 parts, crosslinking agent 2-8 parts; wherein the SBS polymer modifier is linear or star-shaped styrene-butadiene-styrene block copolymer; the preparation method of the above dry SBS modifier is also provided, and the SBS modified asphalt prepared by using the above dry SBS modifier. The dry SBS modifier provided by the above patent can simultaneously play the triple roles of modification, warm mixing and flame retardation on asphalt, and the obtained SBS modified asphalt has excellent pavement construction effect. However, when the SBS modifier is used to modify asphalt in the above patent, the warm mixing and flame retardation modification of asphalt are mainly realized, and the improvement of the rutting resistance of asphalt is less. SUMMARY

[0007] The purpose of the present application is to provide an anti-rutting dry SBS asphalt mixture and a preparation method thereof, which solves the problem of poor anti-rutting performance of the existing asphalt mixture.

[0008] To achieve the above purpose, the present application provides an anti-rutting dry SBS asphalt mixture, which comprises the following components in mass fraction: aggregate 80-90 parts, dry SBS modified asphalt 6-8 parts, modifier 1-2 parts, and mineral powder 5-6 parts.

[0009] Preferably, the modifier comprises the following components in mass percentage: rock asphalt 80%-85%, SiC particles 3%-5%, quartz sand 5%-7%, and silane coupling agent 6%-8%.

[0010] Preferably, the particle size of the SiC particles is 1000-1500 mesh, and the particle size of the quartz sand is 100-200 mesh.

[0011] Preferably, the silane coupling agent is gamma-aminopropyl triethoxysilane.

[0012] Preferably, the dry SBS modified asphalt comprises the following components in mass percentage: 90%-96% of asphalt, 3%-5% of dry SBS particles, 0.3%-0.4% of sulfur, 0.5%-1% of zinc stearate, 0.3%-0.5% of antioxidant, and 0.8%-1% of naphthenic oil.

[0013] Preferably, the particle size of the dry SBS particles is 10-50 mesh, and the dry SBS particles are linear SBS with a molecular weight of 60,000-80,000.

[0014] Preferably, the antioxidant is a mixture of diphenylamine and hydroquinone, the mass ratio of diphenylamine to hydroquinone being 1:0.8-1.2.

[0015] The preparation method of the anti-rutting dry SBS asphalt mixture comprises the following steps:

[0016] S1, preparing dry SBS modified asphalt;

[0017] S2, preparing a modifier;

[0018] S3, adding the modifier into a mixing device according to the mass ratio, mixing with the prepared dry SBS modified asphalt, the heating temperature being 160-180 DEG C, the stirring time being 20-30 minutes, the stirring being uniform, and obtaining a premix;

[0019] S4, adding the premix into aggregate preheated to 170-180 DEG C, stirring for 2-3 minutes, and then adding mineral powder, mixing uniformly to obtain the asphalt mixture.

[0020] Preferably, the S1 comprises the following specific process:

[0021] S11, mixing dry SBS particles, sulfur, zinc stearate, diphenylamine, hydroquinone and naphthenic oil according to the mass ratio, and stirring uniformly;

[0022] S12, adding the mixture and asphalt into a mixing device, stirring for 1-2 minutes at 180-190 DEG C, and obtaining the dry SBS modified asphalt.

[0023] Preferably, the S2 comprises the following specific process:

[0024] S21, mixing quartz sand, SiC particles and silane coupling agent according to the mass percentage, stirring uniformly, and obtaining a mixture;

[0025] S22, adding the mixture into rock asphalt, heating to 150-180 DEG C, stirring for 0.5-2 hours, mixing uniformly, and obtaining the modifier.

[0026] The anti-rutting dry SBS asphalt mixture and the preparation method thereof have the following advantages and positive effects:

[0027] 1. This invention incorporates SiC particles, quartz sand, and a silane coupling agent into asphalt mixtures. The high hardness of SiC particles and quartz sand strengthens the asphalt internally, reducing deformation and improving the rutting resistance of the asphalt mixture. The silane coupling agent enhances the dispersibility of SiC particles and quartz sand in the asphalt, increasing the bonding strength between them. The good thermal conductivity of SiC particles improves the stability of asphalt pavements in both low and high temperature environments. The larger particle size of quartz sand compared to silicon carbide allows silicon carbide to fill the voids in the quartz sand, reinforcing the asphalt. The combined effect of quartz sand and silicon carbide increases the supporting strength of the asphalt, further enhancing the rutting resistance of the asphalt mixture.

[0028] 2. This invention uses dry SBS to modify asphalt and adds zinc stearate to the asphalt. The acidity of stearate helps to improve the dispersibility of SBS in asphalt, so that SBS and asphalt can be mixed evenly, thereby improving the effect of asphalt modification and promoting the cross-linking reaction.

[0029] 3. This invention adds an oxidant composed of a mixture of diphenylamine and hydroquinone to asphalt. Under the synergistic effect of diphenylamine and hydroquinone, the antioxidant effect is improved, and the oxidative decomposition of asphalt at high temperature is inhibited, thus extending the service life of asphalt and improving its stability and durability at high temperatures, as well as its resistance to rutting.

[0030] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0031] Figure 1 This is a flowchart of an embodiment of the present invention. Detailed Implementation

[0032] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "arrangement", "installation", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0033] In the present application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as understood by a person skilled in the art to which the present application belongs. If there is any inconsistency, the meaning described in the specification or derived from the content described in the specification shall prevail. In addition, the terms used herein are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

[0034] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0035] A kind of anti-rut dry SBS asphalt mixture, including the following mass fraction of ingredients: aggregate is 80-90 parts, dry SBS modified asphalt is 6-8 parts, modifier is 1-2 parts, mineral powder is 5-6 parts.

[0036] The modifier includes the following mass percentage of ingredients: rock asphalt 80%-85%, SiC particles 3%-5%, quartz sand 5%-7% and silane coupling agent 6%-8%.

[0037] The particle size of SiC particles is 1000-1500 mesh, and the particle size of quartz sand is 100-200 mesh.

[0038] Silicon carbide nanoparticles have the characteristics of high hardness and high strength. Adding them to asphalt can effectively improve the mechanical properties of asphalt. Nanoparticles are uniformly dispersed in asphalt and can act as reinforcing phase, like a micro "support column", enhancing the ability of asphalt to resist external forces. When subjected to vehicle load, silicon carbide nanoparticles can disperse stress and reduce deformation of asphalt, thereby improving the compressive strength and shear strength of asphalt. When asphalt is used on heavy traffic roads, it can better withstand repeated rolling of vehicles, reduce the occurrence of rutting, cracking and other diseases, and prolong the service life of the road.

[0039] Silicon carbide nanoparticles also have a positive impact on the thermal performance of asphalt. It can improve the thermal stability of asphalt, reduce the flowability of asphalt at high temperatures. In a high-temperature environment, asphalt is prone to softening and flowing, affecting the performance of the road. Silicon carbide nanoparticles can limit the movement of asphalt molecules and enhance the internal structural stability of asphalt. Silicon carbide nanoparticles can also improve the thermal conductivity of asphalt, helping asphalt pavement to quickly dissipate heat in winter, making the pavement temperature closer to the ambient temperature, reducing the internal stress caused by temperature changes and reducing the risk of pavement cracking. In summer, it is also conducive to the rapid heat dissipation of asphalt pavement, reducing the temperature of the pavement, reducing the softening and deformation of asphalt at high temperatures, and improving the anti-rutting performance of the pavement.

[0040] Asphalt will be affected by factors such as oxygen and ultraviolet light during use and will age, resulting in a decrease in performance. Silicon carbide nanoparticles have certain antioxidant and ultraviolet resistance capabilities, which can effectively delay the aging process of asphalt. It can absorb ultraviolet light and reduce the damage of ultraviolet light to asphalt molecules. Silicon carbide nanoparticles can also inhibit the reaction between asphalt and oxygen, reducing the degree of oxidation of asphalt, extending the maintenance cycle of asphalt pavement, and reducing road maintenance costs.

[0041] Quartz sand has high hardness and stable chemical properties, and can form a stable skeleton structure in asphalt. Due to the good wear resistance of quartz sand itself, the uniform distribution of quartz sand in asphalt can resist friction from vehicle tires and the like, extending the service life of asphalt pavement. Quartz sand fills the voids in asphalt, reducing the penetration channels for water and enhancing the waterproof effect of asphalt.

[0042] The particle size of quartz sand is larger than that of silicon carbide, and silicon carbide fills the voids between quartz sand to strengthen asphalt. Under the combined action of quartz sand and silicon carbide, the support strength of asphalt is improved, which is beneficial to improving the anti-rutting performance of asphalt mixture.

[0043] The silane coupling agent is γ-aminopropyl triethoxysilane.

[0044] γ-aminopropyl triethoxysilane changes the surface properties of quartz sand and silicon carbide from originally strong hydrophilic surfaces to certain lipophilic surfaces. This makes the treated particles more easily wetted and wrapped by asphalt. Asphalt molecules can penetrate deeper into the surface of the treated particles, increasing the contact area and interaction force between them, which is beneficial to the dispersion of quartz sand and silicon carbide in asphalt. Asphalt molecules can better fill the voids between the particles, achieve close combination, thereby improving the stability and compactness of the entire system and improving the anti-rutting performance of asphalt mixture.

[0045] The γ-aminopropyl triethoxysilane has inorganic affinity and organic affinity. When it is mixed with quartz sand and silicon carbide, the triethoxyl group forms silanol (-SiOH) after hydrolysis, which can condense with the hydroxyl group (-OH) on the surface of quartz sand and silicon carbide and be firmly connected to the material surface through a silicon-oxygen bond (Si-O-Si). The formation of the chemical bond makes the silane coupling agent closely adhere to the surface of the inorganic material. The aminopropyl group extends outward to provide active sites for interaction with organic matter. The aminopropyl group can form hydrogen bonds or weak chemical reactions with the polar groups in rock asphalt, thereby promoting the mutual penetration and combination of the treated particles and asphalt molecules.

[0046] Rock asphalt has a high softening point. Adding rock asphalt to ordinary asphalt can increase the softening point of the mixed asphalt, making it less likely to deform at high temperatures, effectively resisting deformation caused by vehicle load, thereby improving the high-temperature stability of the pavement and reducing the occurrence of rutting. The polar components in rock asphalt can chemically react with the active sites on the surface of the aggregate to form chemical bonds or strong physical adsorption, allowing the asphalt and aggregate to better bind together. The addition of rock asphalt increases the thickness and toughness of the asphalt film, which can better wrap the aggregate and improve the interlocking action between the aggregates. Thus, under the repeated action of vehicle load, the aggregate is less likely to loosen and displace, thereby maintaining the integrity of the pavement structure and improving the anti-rutting performance.

[0047] The dry SBS modified asphalt comprises the following components by mass percentage: 90%-96% of asphalt, 3%-5% of dry SBS particles, 0.3%-0.4% of sulfur, 0.5%-1% of zinc stearate, 0.3%-0.5% of antioxidant, and 0.8%-1% of naphthenic oil.

[0048] The antioxidant is a mixture of diphenylamine and hydroquinone, and the mass ratio of diphenylamine to hydroquinone is 1:0.8-1.2.

[0049] The particle size of the dry SBS particles is 10-50 mesh, and the dry SBS particles are linear SBS with a molecular weight of 60,000-80,000. Linear SBS imparts good flexibility to asphalt, making it less likely to crack in a low-temperature environment. Linear SBS with too small a molecular weight has a poor modification effect on asphalt, and a molecular weight that is too large affects the dispersion effect and efficiency of linear SBS and asphalt.

[0050] Sulfur can cross-link with the double bonds in SBS under heating conditions, forming a three-dimensional network structure. This cross-linked structure can limit the movement of molecular chains, improve the strength, hardness and heat resistance of asphalt, and reduce the flow and deformation of asphalt at high temperatures, thereby improving the anti-rutting performance of asphalt pavement.

[0051] Zinc stearate has good lubricity and dispersibility. It can reduce the interfacial tension between asphalt and SBS, promote the uniform dispersion of SBS in asphalt, and prevent SBS particles from agglomeration during storage and use. Zinc stearate can also reduce the surface tension of sulfur in asphalt, allowing it to disperse more uniformly in the asphalt system, increasing the contact area between sulfur and SBS particles, and allowing the sulfur cross-linking reaction to proceed more fully and uniformly, improving cross-linking efficiency. During the sulfur cross-linking reaction, some active intermediates are generated. Zinc stearate can interact with these intermediates to stabilize their structure, prevent premature decomposition or side reactions, and thus facilitate the cross-linking reaction in the desired direction, promote the formation of cross-linked network, and improve the performance of modified asphalt.

[0052] Diphenylamine and hydroquinone antioxidants can capture free radicals generated during heating and use of asphalt. Diphenylamine reacts with free radicals to form stable nitrogen-oxygen free radicals, thereby interrupting the free radical chain reaction. Hydroquinone donates hydrogen atoms to combine with free radicals, rendering them inactive. When used together, they can capture free radicals from different pathways, more comprehensively inhibiting the oxidation of asphalt. This prevents asphalt from hardening and becoming brittle due to oxidation, extending the service life of asphalt. Diphenylamine and hydroquinone work together to inhibit thermal oxidative decomposition of asphalt molecules at high temperatures, preventing excessive softening and flow of asphalt at high temperatures, maintaining its good high-temperature performance, and improving the stability and durability of modified asphalt at high temperatures, thereby improving the anti-rutting performance.

[0053] Naphthenic oil has good solubility and compatibility, and can penetrate between SBS particles and asphalt molecules, allowing SBS particles to swell better, increasing the contact area between SBS and asphalt, and promoting interaction between the two.

[0054] As shown in Figure 1 The preparation method of the above anti-rutting dry SBS asphalt mixture comprises the following steps:

[0055] S1, preparing dry SBS modified asphalt.

[0056] The specific process includes:

[0057] S11, dry process SBS particles, sulfur, zinc stearate, diphenylamine, hydroquinone and naphthenic oil are mixed according to the mass ratio, stirred uniformly to obtain a mixture. The stirring time is 30s-60s. The dry process SBS particles are first mixed with the additives, which is beneficial to the uniform mixing of the dry process SBS particles and the additives, and promotes the uniform mixing of the dry process SBS particles and the asphalt.

[0058] S12, the mixture and the asphalt are added to the mixing device, stirred at 180℃-190℃ for 1-2 minutes to obtain the dry process SBS modified asphalt.

[0059] S2, preparation of modifier.

[0060] The specific process includes the following steps:

[0061] S21, quartz sand, SiC particles and silane coupling agent are mixed according to the mass percentage, and stirred uniformly to obtain a mixture.

[0062] S22, the mixture is added to the rock asphalt, heated to 150℃-180℃, stirred for 0.5-2 hours, mixed uniformly to obtain the modifier.

[0063] 150℃-180℃ can make the silane coupling agent hydrolyze and condense quickly, form uniform and stable chemical bonds on the surface of silicon carbide and rock asphalt, and enhance the binding force between them. The rock asphalt has a high softening point, which can make it soften and increase its flowability in this temperature range, which is beneficial to the uniform mixing of silicon carbide and silane coupling agent.

[0064] S3, the modifier is added to the mixing device according to the mass ratio, mixed with the prepared dry process SBS modified asphalt, the heating temperature is 160℃-180℃, the stirring time is 20-30 minutes, and the stirring is uniform to obtain a premix.

[0065] S4, the premix is added to the aggregate preheated to 170℃-180℃, stirred for 2-3 minutes; then the mineral powder is added, and the asphalt mixture is obtained after mixing uniformly.

[0066] The technical method of the present application is described in detail by the following examples and comparative examples.

[0067] In the following examples and comparative examples, the asphalt is Sinopec 70# A-grade road petroleum asphalt, and the rock asphalt is Buton rock asphalt. The mineral powder is S95 grade mineral powder, and the gradation of the aggregate and mineral powder skeleton material is shown in Table 1.

[0068] Table 1 Gradation of aggregate and mineral powder in asphalt mixture

[0069]

[0070] Example 1

[0071] The anti-rutting dry SBS asphalt mixture comprises the following components in mass fraction: aggregate 84 parts, dry SBS modified asphalt 8 parts, modifier 2 parts, and mineral powder 6 parts.

[0072] The modifier comprises the following components in mass percentage: rock asphalt 84%, SiC particles 3%, quartz sand 7%, and silane coupling agent 6%.

[0073] The SiC particles have a particle size of 1300 mesh, and the quartz sand has a particle size of 150 mesh.

[0074] The silane coupling agent is γ-aminopropyl triethoxysilane.

[0075] The dry SBS modified asphalt comprises the following components in weight fraction: 93.9% of asphalt, 4% of dry SBS particles, 0.3% of sulfur, 0.5% of zinc stearate, 0.3% of antioxidant, and 1% of naphthenic oil.

[0076] The dry SBS particles have a particle size of 30 mesh, and the dry SBS particles are linear SBS with a molecular weight of 70,000.

[0077] The antioxidant is a mixture of diphenylamine and hydroquinone, and the mass ratio of diphenylamine to hydroquinone is 1:1.

[0078] The preparation method of the anti-rutting dry SBS asphalt mixture comprises the following steps:

[0079] S1, preparing dry SBS modified asphalt;

[0080] The specific process comprises the following steps:

[0081] S11, mixing dry SBS particles, sulfur, zinc stearate, diphenylamine, hydroquinone, and naphthenic oil according to the mass ratio, and stirring uniformly.

[0082] S12, adding the mixture and asphalt into a mixing device, stirring for 1 minute at a temperature of 180°C, and obtaining dry SBS modified asphalt.

[0083] S2, mixing quartz sand, SiC particles, and silane coupling agent according to the mass percentage, and stirring uniformly to obtain a mixture.

[0084] S3, adding the mixture into rock asphalt, heating to 160°C, stirring for 1 hour, and mixing uniformly to obtain a modifier.

[0085] S4, adding the modifier into the mixing device according to the mass ratio, mixing with the prepared dry SBS modified asphalt, heating at a temperature of 180°C, stirring for 20 minutes, and stirring uniformly to obtain a premix.

[0086] S5, add the premix to the aggregate preheated to 180℃ and stir for 2 minutes; then add the mineral powder and mix uniformly to obtain the asphalt mixture.

[0087] Example 2

[0088] The anti-rutting dry process SBS asphalt mixture comprises the following components in mass fraction: aggregate 85 parts, dry process SBS modified asphalt 7 parts, modifier 2 parts, and mineral powder 6 parts.

[0089] The modifier comprises the following components in mass percentage: rock asphalt 82%, SiC particles 4%, quartz sand 7%, and silane coupling agent 7%.

[0090] The SiC particles have a particle size of 1300 mesh, and the quartz sand has a particle size of 150 mesh.

[0091] The silane coupling agent is γ-aminopropyl triethoxysilane.

[0092] The dry process SBS modified asphalt comprises the following components in weight fraction: 93.5% of asphalt, 4% of dry process SBS particles, 0.4% of sulfur, 0.7% of zinc stearate, 0.4% of antioxidant, and 1% of naphthenic oil.

[0093] The dry process SBS particles have a particle size of 30 mesh, and the dry process SBS particles are linear SBS with a molecular weight of 70,000.

[0094] The antioxidant is a mixture of diphenylamine and hydroquinone, and the mass ratio of diphenylamine to hydroquinone is 1:1.

[0095] The preparation method of the anti-rutting dry process SBS asphalt mixture comprises the following steps:

[0096] S1, preparing dry process SBS modified asphalt;

[0097] The preparation method comprises the following specific processes:

[0098] S11, mixing the dry process SBS particles, sulfur, zinc stearate, diphenylamine, hydroquinone, and naphthenic oil according to the mass ratio and stirring uniformly.

[0099] S12, adding the mixture and asphalt into a mixing device and stirring for 1 minute at a temperature of 180℃ to obtain the dry process SBS modified asphalt.

[0100] S2, mixing the quartz sand, SiC particles, and silane coupling agent according to the mass percentage and stirring uniformly to obtain a mixture.

[0101] S3, adding the mixture into rock asphalt, heating to 160℃, stirring for 1 hour, and mixing uniformly to obtain the modifier.

[0102] S4, the modifier is added into the mixing device according to the mass ratio, mixed with the prepared dry SBS modified asphalt, the heating temperature is 180 DEG C, and stirring for 20 minutes, stirring is uniform, and the premix is obtained.

[0103] S5, the premix is added into the aggregate preheated to 180 DEG C, and stirring for 2 minutes; the mineral powder is added, and the asphalt mixture is obtained after mixing uniformly.

[0104] Example 3

[0105] A dry SBS anti-rutting asphalt mixture, comprising the following components in mass fraction: aggregate 88 parts, dry SBS modified asphalt 6 parts, modifier 1 part, and mineral powder 5 parts.

[0106] The modifier comprises the following components in mass percentage: rock asphalt 84%, SiC particles 5%, quartz sand 5%, and silane coupling agent 6%.

[0107] The particle size of the SiC particles is 1300 mesh, and the particle size of the quartz sand is 150 mesh.

[0108] The silane coupling agent is γ-aminopropyl triethoxysilane.

[0109] The dry SBS modified asphalt comprises the following components in weight fraction: 95.1% of asphalt, 3% of dry SBS particles, 0.3% of sulfur, 0.5% of zinc stearate, 0.3% of antioxidant, and 0.8% of naphthenic oil.

[0110] The particle size of the dry SBS particles is 30 mesh, and the dry SBS particles are linear SBS with a molecular weight of 70,000.

[0111] The antioxidant is a mixture of diphenylamine and hydroquinone, and the mass ratio of diphenylamine to hydroquinone is 1:1.

[0112] The preparation method of the dry SBS anti-rutting asphalt mixture comprises the following steps:

[0113] S1, preparing dry SBS modified asphalt;

[0114] Comprising the following specific process:

[0115] S11, the dry SBS particles, sulfur, zinc stearate, diphenylamine, hydroquinone and naphthenic oil are mixed according to the mass ratio, and stirring is uniform.

[0116] S12, the mixture and the asphalt are added into the mixing device, stirring for 1 minute at 180 DEG C, and the dry SBS modified asphalt is obtained.

[0117] S2, the quartz sand, SiC particles and silane coupling agent are mixed according to the mass percentage, and stirring is uniform, and the mixture is obtained.

[0118] S3, add the mixture to rock asphalt, heat to 160°C, stir for 1 hour, mix evenly, to obtain a modifier.

[0119] S4, add the modifier to the mixing device according to the mass ratio, mix with the prepared dry SBS modified asphalt, the heating temperature is 180°C, stir for 20 minutes, stir evenly, to obtain a premix.

[0120] S5, add the premix to the aggregate preheated to 180°C, stir for 2 minutes; then add the mineral powder, mix evenly to obtain an asphalt mixture.

[0121] Example 4

[0122] The difference between this example and Example 2 is that the ratio of dry SBS modified asphalt in this example is different. The ratio of dry SBS modified asphalt in this example is the same as in Example 1.

[0123] The dry SBS modified asphalt includes the following components by weight: 93.9% asphalt, 4% dry SBS particles, 0.3% sulfur, 0.5% zinc stearate, 0.3% antioxidant, and 1% naphthenic oil.

[0124] Example 5

[0125] The difference between this example and Example 2 is that the ratio of dry SBS modified asphalt in this example is different. The ratio of dry SBS modified asphalt in this example is the same as in Example 3.

[0126] The dry SBS modified asphalt includes the following components by weight: 95.1% asphalt, 3% dry SBS particles, 0.3% sulfur, 0.5% zinc stearate, 0.3% antioxidant, and 0.8% naphthenic oil.

[0127] Example 6

[0128] The difference between this example and Example 2 is that the ratio of the modifier in this example is different. The ratio of the modifier in this example is the same as in Example 1.

[0129] The modifier includes the following components by mass percentage: rock asphalt 84%, SiC particles 3%, quartz sand 7%, and silane coupling agent 6%.

[0130] Example 7

[0131] The difference between this example and Example 2 is that the ratio of the modifier in this example is different. The ratio of the modifier in this example is the same as in Example 3.

[0132] The modifier comprises the following ingredients in mass percentage: rock asphalt 84%, SiC particles 5%, quartz sand 5%, and silane coupling agent 6%.

[0133] Example 8

[0134] The difference between this example and Example 2 is that the particle size of SiC particles in this example is 1300 mesh, and the particle size of quartz sand is 100 mesh.

[0135] Example 9

[0136] The difference between this example and Example 2 is that the particle size of SiC particles in this example is 1300 mesh, and the particle size of quartz sand is 200 mesh.

[0137] Example 10

[0138] The difference between this example and Example 2 is that the particle size of SiC particles in this example is 1000 mesh, and the particle size of quartz sand is 150 mesh.

[0139] Example 11

[0140] The difference between this example and Example 2 is that the particle size of SiC particles in this example is 1500 mesh, and the particle size of quartz sand is 150 mesh.

[0141] Example 12

[0142] The difference between this example and Example 2 is that the particle size of SiC particles in this example is 1500 mesh, and the particle size of quartz sand is 200 mesh.

[0143] Example 13

[0144] The difference between this example and Example 2 is that the mass ratio of diphenylamine to hydroquinone in the antioxidant is 1:0.8.

[0145] Example 14

[0146] The difference between this example and Example 2 is that the mass ratio of diphenylamine to hydroquinone in the antioxidant is 1:1.2.

[0147] Comparative Example 1

[0148] The difference between this example and Example 2 is that the modifier in this example does not contain quartz sand, and the mass percentage of SiC particles is 11%.

[0149] Comparative Example 2

[0150] The difference between this example and Example 2 is that the modifier in this example does not contain SiC particles, and the mass percentage of quartz sand is 11%.

[0151] Comparative Example 3

[0152] The difference between this comparative example and Example 2 is that the antioxidant in this example is diphenylamine.

[0153] Comparative Example 4

[0154] The difference between this comparative example and Example 2 is that the antioxidant in this example is hydroquinone.

[0155] Comparative Example 5

[0156] The difference between this comparative example and Example 2 is that this example does not contain zinc stearate and the mass percentage of naphthenic oil is 1.7%.

[0157] The asphalt mixtures prepared in Examples 1-14 and Comparative Examples 1-5 were respectively molded into cylindrical standard Marshall test pieces, 250mm x 30mm x 35mm beam test pieces and 300mm x 300mm x 50mm rutting test pieces according to the standards, and water stability performance, low temperature performance and rutting resistance performance were studied. The test procedures were in accordance with T0709-2011 "Marshall Stability Test of Asphalt Mixture" and T0719-2011 "Asphalt Mixture Rutting Test" in JTG E20-2011 "Standard Test Methods of Bitumen and Asphalt Mixture for Highway Engineering".

[0158] Low temperature performance test: the temperature in the box was controlled at -10°C when the test piece was damaged, and the maximum bending tensile strain me at the time of damage of the test piece was used as the evaluation index.

[0159] Rutting resistance performance test: the rutting test of the asphalt mixture was carried out at 60°C and 0.7MPa on the rutting test piece.

[0160] The test results of the asphalt mixtures prepared in Examples 1-14 and Comparative Examples 1-5 are shown in Table 2.

[0161] Table 2 Performance of the asphalt mixtures prepared in Examples 1-14 and Comparative Examples 1-5

[0162]

[0163] From the test results of Table 2, it can be seen that the different modifier addition amount and different dry process SBS modified asphalt addition amount have certain influence on the anti-rutting performance and stability of the asphalt mixture. Adding the mixture of silicon carbide particles and quartz sand in the modifier of the asphalt mixture is beneficial to improve the anti-rutting performance and low temperature performance of the asphalt mixture. The particle size of the silicon carbide particles and the quartz sand also has certain influence on the anti-rutting performance and low temperature performance of the asphalt mixture. The combined addition of the antioxidants and zinc stearate also has certain influence on the anti-rutting performance and low temperature performance of the asphalt mixture. The dynamic stability of the asphalt mixture obtained by reasonably distributing the components and selecting the appropriate preparation method reaches more than 10000 times / mm, the Marshall stability is more than 15kN, the maximum bending tensile strain reaches 3900, the residual stability is more than 95%, and the asphalt mixture has very good anti-rutting performance and low temperature stability.

[0164] Therefore, the anti-rutting dry process SBS asphalt mixture and the preparation method thereof can solve the problem of poor anti-rutting performance of the existing asphalt mixture and improve the low temperature stability of the asphalt mixture.

[0165] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application but not to limit it, although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that: it can still modify or equivalently replace the technical solutions of the present application, and these modifications or equivalent replacements also cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1. An anti-rut dry process SBS asphalt mixture, characterized by, The components include the following mass fractions: aggregate 80-90 parts, dry SBS modified asphalt 6-8 parts, modifier 1-2 parts, and mineral powder 5-6 parts; The modifier includes the following mass percentages of components: rock asphalt 80%-85%, SiC particles 3%-5%, quartz sand 5%-7%, and silane coupling agent 6%-8%; The SiC particles have a particle size of 1000-1500 mesh, and the quartz sand has a particle size of 100-200 mesh; The dry SBS modified asphalt includes the following mass percentages of components: 90%-96% of asphalt, 3%-5% of dry SBS particles, 0.3%-0.4% of sulfur, 0.5%-1% of zinc stearate, 0.3%-0.5% of antioxidant, and 0.8%-1% of naphthenic oil; The antioxidant is a mixture of diphenylamine and hydroquinone, and the mass ratio of diphenylamine to hydroquinone is 1:0.8-1.

2.

2. The anti-rutting dry process SBS asphalt mixture according to claim 1, characterized in that: The silane coupling agent is γ-aminopropyl triethoxysilane.

3. The anti-rut dry process SBS asphalt mixture according to claim 2, characterized in that: The dry SBS particles have a particle size of 10-50 mesh, and the dry SBS particles are linear SBS with a molecular weight of 60,000-80,000.

4. A method of producing a rut-resistant dry process SBS asphalt mixture according to claim 3, characterized in that, The method includes the following steps: S1, preparing dry SBS modified asphalt; S2, preparing a modifier; S3, adding the modifier to a mixing device according to the mass ratio, mixing with the prepared dry SBS modified asphalt, heating at a temperature of 160-180°C, stirring for 20-30 minutes, and stirring uniformly to obtain a premix; S4, adding the premix to aggregate preheated to 170-180°C, stirring for 2-3 minutes, and then adding mineral powder to obtain asphalt mixture after mixing uniformly.

5. A process for the preparation of a rut resistant dry process SBS bituminous mixture as claimed in claim 4, wherein, The S1 includes the following specific process: S11, mixing dry SBS particles, sulfur, zinc stearate, diphenylamine, hydroquinone, and naphthenic oil according to the mass ratio, and stirring uniformly; S12, adding the mixture and asphalt to a mixing device, stirring at a temperature of 180-190°C for 1-2 minutes, and obtaining dry SBS modified asphalt.

6. A process for the preparation of a rut resistant dry process SBS bituminous mixture as claimed in claim 5, wherein, The S2 includes the following specific process: S21, mixing quartz sand, SiC particles, and silane coupling agent according to the mass percentage, stirring uniformly, and obtaining a mixture; S22, adding the mixture to rock asphalt, heating to 150-180°C, stirring for 0.5-2 hours, mixing uniformly, and obtaining a modifier.

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