High performance modified asphalt mixture and method of making same

Abstract

The application relates to the technical field of modified asphalt, in particular to a high-performance modified asphalt mixture and a preparation method thereof.A high-performance modified asphalt mixture comprises the following raw materials in mass fractions: modified asphalt 5.0-7.5 parts, SBS grafted maleic anhydride 0.40-0.80 parts, polycaprolactone 0.15-0.30 parts, rubber oil 0.30-0.75 parts, dioctyl adipate 0.045-0.105 parts, stabilizer 0.01-0.015 parts, polyester fiber 0.25-0.45 parts, aggregate 79.5-89.0 parts and filler 7.0-12.5 parts; through optimization of the raw material composition ratio, the high-temperature stability and water stability of the pavement can be improved, the pavement has good road performance and fatigue resistance, the fatigue resistance of the asphalt pavement under the action of vehicle load can be remarkably improved, and the service life of the pavement is prolonged.

Description

Technical Field

[0001] This application relates to the field of modified asphalt technology, and in particular to a high-performance modified asphalt mixture and its preparation method. Background Technology

[0002] Asphalt mixture is a composite material mainly composed of asphalt, coarse aggregate, fine aggregate, and mineral powder, sometimes with the addition of polymers and wood cellulose. These materials, in varying quantities and qualities, form different structures and possess different mechanical properties. The most commonly used asphalt mixture in engineering is a mixture of appropriately proportioned coarse aggregate, fine aggregate, and fillers, conforming to a specified gradation, mixed with asphalt binder, and compacted to achieve a residual void ratio of less than 10%, commonly referred to as asphalt concrete.

[0003] With the continuous development of technology, modern highways have undergone many changes. Traffic flow and frequency have increased dramatically, the axle load of freight vehicles has been constantly increasing, and lane-separated one-way traffic has become commonplace. This necessitates further improvements in pavement durability, namely, enhancing resistance to rutting at high temperatures and improving the fatigue resistance of asphalt pavements under increasing traffic loads. Therefore, there is an urgent need to develop an asphalt mixture with good high-temperature and water stability, excellent road performance, and good fatigue resistance. Summary of the Invention

[0004] To address the problems in the prior art, this application provides a high-performance modified asphalt mixture and its preparation method.

[0005] Firstly, the high-performance modified asphalt mixture provided in this application adopts the following technical solution:

[0006] A high-performance modified asphalt mixture comprises the following raw materials in parts by weight: 5.0-7.5 parts modified asphalt, 0.40-0.80 parts SBS grafted maleic anhydride, 0.15-0.30 parts polycaprolactone, 0.30-0.75 parts rubber oil, 0.045-0.105 parts dioctyl adipate, 0.01-0.015 parts stabilizer, 0.25-0.45 parts polyester fiber, 79.5-89.0 parts aggregate, and 7.0-12.5 parts filler, wherein SBS is a styrene-butadiene-styrene block copolymer.

[0007] By adopting the above technical solutions, the modified asphalt possesses bonding ability and viscosity, enabling it to firmly bond other components with aggregates, thus providing the overall performance, high-temperature stability, and water stability of the mixture. SBS-grafted maleic anhydride increases the elasticity and flexibility of the asphalt, improving the crack resistance, deformability, and water stability of the mixture. Polycaprolactone increases the flexibility and toughness of the mixture, enhancing fatigue resistance and durability. Rubber oil improves the elasticity and flexibility of the mixture, increasing its adhesion and deformability. Dioctyl adipate improves the low-temperature resistance and crack resistance of the mixture. Stabilizers enhance the stability of the modified asphalt and prevent segregation. Polyester fibers increase the crack resistance and shear strength of the mixture, improving its mechanical properties and durability. Aggregates provide mechanical support and structural stability to the mixture. Fillers fill the internal structure of the asphalt mixture, improving stability and enhancing the fatigue resistance of the modified asphalt mixture. The synergistic effect among these components gives the modified asphalt mixture good high-temperature stability and water stability, excellent road performance, and good fatigue resistance. By improving the elasticity and flexibility of the asphalt mixture, increasing its deformation capacity and crack resistance, and enhancing its durability, the resulting high-performance modified asphalt mixture can effectively improve the fatigue resistance of asphalt pavements under increasing traffic loads.

[0008] Preferably, the modified asphalt comprises base asphalt and a modifier, wherein the modifier comprises high-density polyethylene and ethylene-vinyl acetate copolymer, and the mass ratio of high-density polyethylene to ethylene-vinyl acetate is 3:1-2; the amount of modifier added is 3-4% of the mass of base asphalt, and the base asphalt is 70# asphalt or 90# asphalt; the modified asphalt is prepared by: preheating the base asphalt to 165°C, adding the modifier to the base asphalt, maintaining it at 170°C for 15 min, subjecting the mixture of base asphalt and modifier to high-speed shearing at a shearing speed of 4500 rpm for 1 h, and obtaining the modified asphalt after shearing.

[0009] By adopting the above technical solution, the base asphalt serves as the main component of the mixture, while the modifier is added to improve the asphalt's performance. The modifier enhances the high-temperature and water stability of the asphalt, giving the mixture better durability and fatigue resistance. High-density polyethylene and ethylene-vinyl acetate copolymer, as modifiers, can improve the toughness and viscosity of the asphalt, enhancing its stability at high temperatures. Modified asphalt exhibits better road performance; the modifier fills the defects and pores in the base asphalt, improving its adhesion and stability. Simultaneously, the elasticity of the base asphalt enhances the dispersibility and stability of the modifier. After modification, the modified asphalt possesses higher fatigue resistance, effectively resisting fatigue damage caused by traffic loads.

[0010] Preferably, the SBS is grafted with maleic anhydride, the maleic anhydride grafting rate is 0.35%, and the SBS is a styrene-butadiene-styrene block copolymer.

[0011] Preferably, the stabilizer is one of sulfur, tetramethylthiuram disulfide, and dibenzothiazole disulfide.

[0012] Preferably, the aggregate is one of basalt and diabase.

[0013] Preferably, the basalt has a grain size of 0-5mm, 5-10mm, or 10-15mm, and the diabase has a grain size of 0-5mm, 5-10mm, or 10-15mm.

[0014] Preferably, the filler is a composition of limestone powder and modified aluminum nitride in a mass ratio of 10:1-3, wherein the particle size of the limestone powder and the modified aluminum nitride is 0-0.5 mm.

[0015] Preferably, the modified aluminum nitride is graphene oxide-modified aluminum nitride, and its preparation method includes the following steps:

[0016] S81. Add 10g of graphene oxide and 500g of aluminum nitride to 350g of anhydrous ethanol and stir for 25-35 minutes.

[0017] S82. Sonicate the mixed solution for 15-25 minutes to disperse it;

[0018] S83. Gel at 75-85℃, dry at 100-105℃ for 10-12h, ball mill for 1-2.5h, and sieve to obtain graphene oxide modified aluminum nitride with a particle size of 0-0.5mm.

[0019] By adopting the above technical solution, limestone powder and graphene oxide-modified aluminum nitride are components of the filler. Limestone powder is an inorganic material with excellent durability and stability, which can improve the strength and durability of modified asphalt mixtures. Graphene oxide-modified aluminum nitride, composed of graphene oxide-modified aluminum nitride powder, can significantly improve the high-temperature stability and water stability of modified asphalt mixtures. The addition of graphene oxide-modified aluminum nitride filler can effectively improve the thermal conductivity of modified asphalt mixtures, allowing the pavement to dissipate heat better, reducing the rise in pavement temperature, thereby reducing the risk of pavement deformation and aging, and further enhancing the fatigue resistance of modified asphalt mixtures. The combination of limestone powder and graphene oxide-modified aluminum nitride, mixed in a certain mass ratio, can fully utilize the performance advantages of the filler and improve the overall performance of high-performance modified asphalt mixtures. The particle size of limestone powder and graphene oxide-modified aluminum nitride is in the range of 0-0.5 mm, which is suitable for the use of fillers in high-performance modified asphalt mixtures, providing optimal filling and interaction effects. The synergistic effect of the two can improve the fatigue resistance of modified asphalt mixtures, extend the service life of pavements, and enhance the stability and durability of pavements, giving them excellent road performance under complex environments such as vehicle loads and temperature changes.

[0020] Secondly, this application provides a method for preparing high-performance modified asphalt mixture, employing the following technical solution:

[0021] A method for preparing a high-performance modified asphalt mixture, using the aforementioned raw materials for a high-performance modified asphalt mixture, includes the following steps:

[0022] S91. According to the mass fraction, first heat the modified base asphalt to 160-170℃, then add rubber oil and stir evenly to obtain mixture A. Then continue to heat mixture A to 175-185℃. During the continued heating process, add SBS grafted maleic anhydride and polycaprolactone evenly to mixture A, stir and swell for 30 minutes, then shear emulsify at 180-190℃ for 25-30 minutes. Finally, add dioctyl adipate and stabilizer and stir at low speed at 180-190℃ for 60-70 minutes to obtain mixture B, and keep it warm for later use.

[0023] S92. According to the mass fractions, preheat the aggregates and fillers at 180-190℃ for 5-7 hours respectively;

[0024] S93. According to the mass fraction, heat the mixing pot to a mixing temperature of 170-180℃. First, add the preheated aggregate to the mixing pot and mix for 10-15 seconds. Then, add the polyester fiber and mix for 15-20 seconds. Next, add the heat-preserved mixture B from step S91 and mix for 70-90 seconds. Finally, add the preheated filler and mix for 70-90 seconds to obtain a high-performance modified asphalt mixture.

[0025] In summary, the beneficial technical effects of this application are as follows:

[0026] 1. The high-performance modified asphalt mixture of this application can improve the high temperature stability and water stability of the pavement by optimizing the raw material composition, and has good road performance and fatigue resistance. It can significantly improve the fatigue resistance of asphalt pavement under vehicle load and extend the service life of the pavement.

[0027] 2. Improve the high temperature and water stability of the road surface: By adding raw materials such as SBS grafted maleic anhydride, polycaprolactone, and rubber oil, the high temperature aging resistance and water stability of modified asphalt can be significantly improved, so that the road surface can maintain stable performance in high temperature and humid environments.

[0028] 3. Excellent fatigue resistance: By adding raw materials such as dioctyl adipate and polyester fiber, the fatigue resistance of modified asphalt can be significantly improved. Under increasing traffic loads, modified asphalt mixtures can better resist pavement fatigue damage and extend the service life of the pavement.

[0029] 4. The addition of graphene oxide-modified aluminum nitride filler can effectively improve the thermal conductivity of modified asphalt mixtures, enabling the road surface to dissipate heat better, reducing the rise in road surface temperature, thereby reducing the risk of road surface deformation and aging, and further enhancing the fatigue resistance of modified asphalt mixtures. Detailed Implementation

[0030] The embodiments of this application will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of this application. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0031] Example 1

[0032] A high-performance modified asphalt mixture comprises the following raw materials in parts by weight: 7.5 kg modified asphalt, 0.80 kg SBS-grafted maleic anhydride, 0.30 kg polycaprolactone, 0.75 kg rubber oil, 0.105 kg dioctyl adipate, 0.015 kg sulfur, 0.45 kg polyester fiber, 89.0 kg aggregate, and 12.5 kg filler. The modified asphalt comprises base asphalt and a modifier, wherein the modifier comprises high-density polyethylene and ethylene-vinyl acetate copolymer. The mass ratio of high-density polyethylene to ethylene-vinyl acetate is 3:1; the amount of modifier added is 3% of the mass of the base asphalt, and the base asphalt is 70# asphalt. The modified asphalt is prepared by: preheating the 70# asphalt to 165°C according to the mass ratio; adding the modifier to the base asphalt; maintaining the temperature at 170°C for 15 minutes; subjecting the mixture of base asphalt and modifier to high-speed shearing at a shearing speed of 4500 rpm for 1 hour; and obtaining the modified asphalt after shearing. The SBS is grafted with maleic anhydride, and the maleic anhydride grafting rate is 0.35%. The aggregate is basalt with a particle size of 0-5mm, 5-10mm, and 10-15mm, and the mass ratio of the basalt particle size of 0-5mm, 5-10mm, and 10-15mm is 1.8:3.2:5. The filler is a composition of limestone powder and modified aluminum nitride in a mass ratio of 10:1, and the particle size of both the limestone powder and the modified aluminum nitride is 0-0.5mm.

[0033] The modified aluminum nitride is graphene oxide-modified aluminum nitride, and its preparation method includes the following steps:

[0034] S81. Add 10g of graphene oxide and 500g of aluminum nitride to 350g of anhydrous ethanol and stir for 35min. S82. Sonicate the mixed solution for 25min to disperse it.

[0035] S83. Gel formation was carried out at 85℃, followed by drying at 105℃ for 12 hours. After drying, the material was ball-milled for 2.5 hours and then sieved to obtain graphene oxide-modified aluminum nitride with a particle size of 0-0.5 mm.

[0036] A method for preparing a high-performance modified asphalt mixture, using the above-mentioned raw materials, includes the following steps:

[0037] S91. According to the mass fraction, first heat the modified base asphalt to 160℃, then add rubber oil and stir evenly to obtain mixture A. Then continue to heat mixture A to 185℃. During the continued heating process, add SBS grafted maleic anhydride and polycaprolactone evenly to mixture A, stir and swell for 30 min, then shear emulsify at 190℃ for 30 min, and finally add dioctyl adipate and sulfur and stir at low speed at 190℃ for 70 min to obtain mixture B. Keep it warm for later use.

[0038] S92. According to the mass fractions, preheat the aggregates and fillers at 190℃ for 7 hours respectively;

[0039] S93. According to the mass fraction, heat the mixing pot to the mixing temperature of 180℃. First, add the preheated aggregate into the mixing pot and mix for 15s. Then, add the polyester fiber and mix for 20s. Next, add the heat-preserved mixture B from step S91 and mix for 90s. Finally, add the preheated filler and mix for 90s to obtain a high-performance modified asphalt mixture.

[0040] Example 2

[0041] A high-performance modified asphalt mixture comprises the following raw materials in parts by weight: 5.0 kg modified asphalt, 0.40 kg SBS-grafted maleic anhydride, 0.15 kg polycaprolactone, 0.30 kg rubber oil, 0.045 kg dioctyl adipate, 0.01 kg tetramethylthiuram disulfide, 0.25 kg polyester fiber, 79.5 kg aggregate, and 7.0 kg filler. The modified asphalt comprises base asphalt and a modifier, wherein the modifier comprises high-density polyethylene and ethylene-vinyl acetate copolymer. The mass ratio of vinyl acetate is 3:2; the amount of modifier added is 4% of the mass of the base asphalt, the base asphalt is 90# asphalt, and the modified asphalt is prepared by the following method: according to the mass ratio, the 90# asphalt is preheated to 165°C, the modifier is added to the base asphalt, and the mixture is kept at 170°C for 15 min. The mixture of base asphalt and modifier is subjected to high-speed shearing at a shearing speed of 4500 rpm for 1 h. After shearing, the modified asphalt is obtained. The SBS is grafted with maleic anhydride, and the maleic anhydride grafting rate is 0.35%. The aggregate is diabase with a particle size of 0-5mm, 5-10mm, and 10-15mm, and the mass ratio of the diabase with particle sizes of 0-5mm, 5-10mm, and 10-15mm is 2.2:3.0:4.8. The filler is a composition of limestone powder and modified aluminum nitride in a mass ratio of 10:3, and the particle size of both the limestone powder and the modified aluminum nitride is 0-0.5mm.

[0042] The modified aluminum nitride is graphene oxide-modified aluminum nitride, and its preparation method includes the following steps:

[0043] S81. Add 10g of graphene oxide and 500g of aluminum nitride to 350g of anhydrous ethanol and stir for 25min. S82. Sonicate the mixed solution for 15min to disperse it.

[0044] S83. Gel at 75℃, dry at 100℃ for 10h, ball mill for 1h after drying, and sieve to obtain graphene oxide modified aluminum nitride with a particle size of 0-0.5mm.

[0045] A method for preparing a high-performance modified asphalt mixture, using the above-mentioned raw materials, includes the following steps:

[0046] S91. According to the mass fraction, first heat the modified base asphalt to 170℃, then add rubber oil and stir evenly to obtain mixture A. Then continue to heat mixture A to 175℃. During the continued heating process, add SBS grafted maleic anhydride and polycaprolactone evenly to mixture A, stir and swell for 30 minutes, then shear emulsify at 180℃ for 25 minutes. Finally, add dioctyl adipate and tetramethylthiuram disulfide and stir at low speed at 180℃ for 60 minutes to obtain mixture B, and keep it warm for later use.

[0047] S92. According to the mass fractions, preheat the aggregates and fillers at 180℃ for 5 hours respectively;

[0048] S93. According to the mass fraction, heat the mixing pot to the mixing temperature of 170℃. First, add the preheated aggregate into the mixing pot and mix for 10 seconds. Then, add the polyester fiber and mix for 15 seconds. Next, add the heat-preserved mixture B from step S91 and mix for 70 seconds. Finally, add the preheated filler and mix for 70 seconds to obtain a high-performance modified asphalt mixture.

[0049] Example 3

[0050] A high-performance modified asphalt mixture comprises the following raw materials in parts by weight: 6.5 kg modified asphalt, 0.60 kg SBS-grafted maleic anhydride, 0.20 kg polycaprolactone, 0.55 kg rubber oil, 0.085 kg dioctyl adipate, 0.013 kg dibenzothiazole disulfide, 0.35 kg polyester fiber, 85.0 kg aggregate, and 10.5 kg filler. The modified asphalt comprises base asphalt and a modifier, wherein the modifier comprises high-density polyethylene and ethylene-vinyl acetate copolymer. The high-density polyethylene and ethylene-vinyl acetate have a mass ratio of 3:1.5. The modifier is added at 3.5% of the mass of the base asphalt, which is 90# asphalt. The modified asphalt is prepared by preheating the 90# asphalt to 165°C according to the mass ratio, adding the modifier to the base asphalt, maintaining the temperature at 170°C for 15 minutes, and then subjecting the mixture of base asphalt and modifier to high-speed shearing at a shearing speed of 4500 rpm for 1 hour. The modified asphalt is obtained after shearing. The SBS is grafted with maleic anhydride, and the maleic anhydride grafting rate is 0.35%. The aggregate is basalt with a particle size of 0-5mm, 5-10mm, and 10-15mm, and the mass ratio of the basalt particle size of 0-5mm, 5-10mm, and 10-15mm is 1.7:3.5:4.8. The filler is a composition of limestone powder and modified aluminum nitride in a mass ratio of 10:2, and the particle size of both the limestone powder and the modified aluminum nitride is 0-0.5mm.

[0051] The modified aluminum nitride is graphene oxide-modified aluminum nitride, and its preparation method includes the following steps:

[0052] S81. Add 10g of graphene oxide and 500g of aluminum nitride to 350g of anhydrous ethanol and stir for 30min. S82. Sonicate the mixed solution for 20min to disperse it.

[0053] S83. Gel formation was carried out at 80℃, followed by drying at 103℃ for 11 hours. After drying, the material was ball-milled for 2 hours and sieved to obtain graphene oxide modified aluminum nitride with a particle size of 0-0.5 mm.

[0054] A method for preparing a high-performance modified asphalt mixture, using the above-mentioned raw materials, includes the following steps:

[0055] S91. According to the mass fraction, first heat the modified base asphalt to 165℃, then add rubber oil and stir evenly to obtain mixture A. Then continue to heat mixture A to 180℃. During the continued heating process, add SBS grafted maleic anhydride and polycaprolactone evenly to mixture A, stir and swell for 30 min, then shear emulsify at 185℃ for 28 min. Finally, add dioctyl adipate and dibenzothiazole disulfide and stir at low speed at 185℃ for 65 min to obtain mixture B, and keep it warm for later use.

[0056] S92. According to the mass fractions, preheat the aggregates and fillers at 185℃ for 6 hours respectively;

[0057] S93. According to the mass fraction, heat the mixing pot to the mixing temperature of 175℃. First, add the preheated aggregate into the mixing pot and mix for 13s. Then, add the polyester fiber and mix for 18s. Next, add the heat-preserved mixture B from step S91 and mix for 80s. Finally, add the preheated filler and mix for 80s to obtain a high-performance modified asphalt mixture.

[0058] Comparative Example 1

[0059] Similar to Example 3, except that an equal amount of 90# asphalt is used instead of modified asphalt.

[0060] Comparative Example 2

[0061] Similar to Example 3, except that an equal amount of thermoplastic elastomer polystyrene-polybutadiene-polystyrene triblock copolymer with a molecular weight of 50,000-60,000 and a styrene mass content of 28% is used instead of SBS grafted maleic anhydride, with a maleic anhydride grafting rate of 0.35%.

[0062] Comparative Example 3

[0063] Similar to Example 3, except that: equal amounts of filler, namely limestone powder and aluminum nitride in a mass ratio of 10:2, are used instead of the filler in Example 3, and the limestone powder and aluminum nitride have a particle size of 0-0.5 mm. However, the aluminum nitride is not modified by graphene oxide.

[0064] Comparative Example 4

[0065] Similar to Example 3, except that: an equal amount of limestone powder is used as filler, and the particle size of the limestone powder is 0-0.5 mm, replacing the filler in Example 3, that is, the filler does not contain graphene oxide modified aluminum nitride.

[0066] Comparative Example 5

[0067] Same as Example 3, except that no polyester fiber was added.

[0068] Performance testing

[0069] The dynamic stability of the asphalt mixtures prepared in Examples 1-3 and Comparative Examples 1-5 was tested according to the "Rutting Test of Asphalt Mixtures" (T0719-1993) under the following conditions: 60±1℃ and test wheel pressure of 0.7±0.05MPa. The water stability of the asphalt mixtures prepared in Examples 1-3 and Comparative Examples 1-5 was tested according to the "Test Procedures for Asphalt and Asphalt Mixtures" (T0729-2000). The fatigue life of the asphalt mixtures prepared in Examples 1-3 and Comparative Examples 1-5 was tested according to the "Four-Point Bending Fatigue Life Test of Asphalt Mixtures" (T0739-2011). The test results are shown in Table 1.

[0070] Table 1 Performance Test Table

[0071]

[0072] As can be seen from Example 13 and Table 1, the high-performance modified asphalt mixture prepared in this application exhibits excellent dynamic stability, water stability, and long fatigue life. By optimizing the raw material composition, the high-performance modified asphalt mixture of this application can improve the high-temperature stability and water stability of the pavement, possessing good road performance and fatigue resistance. It can significantly enhance the fatigue resistance of asphalt pavement under vehicle loads and extend the service life of the pavement.

[0073] As can be seen from Example 3 and Comparative Example 1, and in conjunction with Table 1, the modified asphalt obtained using the present application exhibits superior dynamic stability, water stability, and fatigue life compared to 90# asphalt.

[0074] As can be seen from Example 3 and Comparative Example 2, and Table 1, the modified asphalt mixture obtained by grafting maleic anhydride with SBS exhibits superior dynamic stability, water stability, and fatigue life compared to the thermoplastic elastomer polystyrene-polybutadiene-polystyrene triblock copolymer with a molecular weight of 50,000-60,000 and a styrene content of 28%.

[0075] As can be seen from Example 3 and Comparative Examples 3-4, and Table 1, the modified asphalt mixture obtained by adding graphene oxide-modified aluminum nitride to the filler exhibits superior dynamic stability, water stability, and fatigue life. Graphene oxide-modified aluminum nitride has thermal conductivity, which can improve the thermal conductivity of the mixture, promote uniform temperature distribution on the road surface, reduce the impact of temperature differences on the road surface, and improve the thermal stability and crack resistance of the road surface. In synergy with limestone powder, it jointly enhances the high-temperature stability, water stability, and fatigue resistance of the mixture, giving it excellent road performance under complex environments such as vehicle loads and temperature changes.

[0076] As can be seen from Example 3 and Comparative Example 5, and in conjunction with Table 1, the addition of polyester fiber, with its synergistic effect with dioctyl adipate, significantly improves the fatigue resistance of modified asphalt. Under increasing traffic loads, the modified asphalt mixture can better resist pavement fatigue damage and extend the service life of the pavement.

[0077] The above embodiments are only used to explain the technical solutions of the present invention and not to limit it. Although the above embodiments have provided specific descriptions of the present invention, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications and equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A high-performance modified asphalt mixture, characterized in that, The raw materials include the following parts by weight: 5.0-7.5 parts modified asphalt, 0.40-0.80 parts SBS-grafted maleic anhydride, 0.15-0.30 parts polycaprolactone, 0.30-0.75 parts rubber oil, 0.045-0.105 parts dioctyl adipate, 0.01-0.015 parts stabilizer, 0.25-0.45 parts polyester fiber, 79.5-89.0 parts aggregate, and 7.0-12.5 parts filler; the modified asphalt... The mixture comprises a base asphalt and a modifier. The modifier comprises high-density polyethylene and ethylene-vinyl acetate copolymer, wherein the mass ratio of high-density polyethylene to ethylene-vinyl acetate is 3:1-2. The amount of modifier added is 3-4% of the mass of the base asphalt, and the base asphalt is 70# or 90# asphalt. The maleic anhydride grafting rate of the SBS grafted maleic anhydride is 0.35%. The stabilizer is one of sulfur, tetramethylthiuram disulfide, and dibenzothiazole disulfide. The filler is a composition of limestone powder and modified aluminum nitride in a mass ratio of 10:1-3, wherein the particle size of both the limestone powder and the modified aluminum nitride is 0-0.5 mm; the modified aluminum nitride is graphene oxide-modified aluminum nitride, and its preparation method includes the following steps: S81. Add 10g of graphene oxide and 500g of aluminum nitride to 350g of anhydrous ethanol and stir for 25-35 minutes. S82. Sonicate the mixed solution for 15-25 minutes to disperse it; S83. Gel at 75-85℃, dry at 100-105℃ for 10-12h, ball mill for 1-2.5h, and sieve to obtain graphene oxide modified aluminum nitride with a particle size of 0-0.5mm.

2. The high-performance modified asphalt mixture according to claim 1, characterized in that, The aggregate is one of basalt or diabase.

3. The high-performance modified asphalt mixture according to claim 2, characterized in that, The basalt has a grain size of 0-5mm, 5-10mm, or 10-15mm, and the diabase has a grain size of 0-5mm, 5-10mm, or 10-15mm.

4. A method for preparing the high-performance modified asphalt mixture according to any one of claims 1-3, characterized in that, Includes the following steps: S91. According to the mass fraction, first heat the modified asphalt to 160-170℃, then add rubber oil and stir evenly to obtain mixture A. Then continue to heat mixture A to 175-185℃. During the continued heating process, add SBS grafted maleic anhydride and polycaprolactone evenly to mixture A, stir and swell for 30 minutes, then shear emulsify at 180-190℃ for 25-30 minutes. Finally, add dioctyl adipate and stabilizer and stir at low speed at 180-190℃ for 60-70 minutes to obtain mixture B, and keep it warm for later use. S92. According to the mass fractions, preheat the aggregates and fillers at 180-190℃ for 5-7 hours respectively; S93. According to the mass fraction, heat the mixing pot to a mixing temperature of 170-180℃. First, add the preheated aggregate to the mixing pot and mix for 10-15 seconds. Then, add the polyester fiber and mix for 15-20 seconds. Next, add the heat-preserved mixture B from step S91 and mix for 70-90 seconds. Finally, add the preheated filler and mix for 70-90 seconds to obtain a high-performance modified asphalt mixture.

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