Elastomer modified asphalt material for long-life pavement structure and preparation method of elastomer modified asphalt material

Abstract

The invention relates to the technical field of road engineering materials, in particular to an elastomer modified asphalt material for a long-life pavement structure and a preparation method of the elastomer modified asphalt material, and the elastomer modified asphalt material comprises an optimized preparation process and performance improvement design. The low-temperature crack resistance, aging resistance and construction performance of the material are remarkably improved by combining the elastomer polymer, the cross-linking agent and the stabilizer according to a specific ratio and combining degassing treatment and a nano doping technology. The softening point of the material is not lower than 60 DEG C, the brittle point is not higher than-20 DEG C, the ductility is not lower than 50 cm at 15 DEG C, and the production cost is reduced by 10%-15%. The problems of insufficient performance stability and the like in the prior art are solved, the requirements of high performance and low cost are met, and the method is suitable for long-service-life pavement construction under extreme weather conditions.

Description

Technical Field

[0001] This invention belongs to the field of road engineering materials technology, specifically an elastomeric modified asphalt material for long-life pavement structures and its application method. Background Technology

[0002] With the increasing demand for long-life pavement structures in the road engineering field, elastomeric modified asphalt materials have gradually become a research hotspot due to their excellent performance. These materials have significant advantages in improving pavement crack resistance, durability, and high-temperature stability, effectively extending pavement service life and reducing maintenance costs. However, existing elastomeric modified asphalt materials and their application methods still have some shortcomings in practical use, limiting their further promotion and application.

[0003] A search revealed a road preventative maintenance material and its construction method, published on May 21, 2019, with publication number CN109777218A. This patent describes a road preventative maintenance material prepared using a specific ratio of modified acrylic resin, dispersant, fumed silica, filler, and colorant, along with a curing agent. This material exhibits good adhesion, bonding firmly to cement concrete and asphalt pavements, preventing moisture or debris from entering pavement cracks, thereby extending pavement lifespan. However, this technical solution involves a large variety of raw materials and a wide range of proportions, potentially leading to significant fluctuations in material performance and making precise quality control difficult. Furthermore, this solution does not adequately consider the material's crack resistance and long-term aging performance under low-temperature conditions, which may affect its applicability under extreme climatic conditions.

[0004] A search revealed a road marking material and method, published on March 16, 2016, with publication number CN103842591B. This patent discloses a thermoplastic road marking material comprising a compatible blend of ethylene-acrylic acid polymers and possessing a high crystallization initiation temperature (greater than 65.6℃). This material exhibits good high-temperature stability and resistance to deformation upon cooling, making it suitable for road marking construction. However, the material formulation design in this technical solution primarily focuses on optimizing high-temperature performance, with less attention paid to flexibility and crack resistance in low-temperature environments, potentially making it difficult to meet the needs of long-life pavement structures in cold regions. Furthermore, the solution does not explicitly mention the material's weather resistance and anti-aging properties during long-term use, which may have certain limitations.

[0005] The aforementioned problems indicate that existing elastomeric modified asphalt materials and their application methods still have certain shortcomings in terms of performance stability, low-temperature crack resistance, aging resistance, and simplification of production processes. Therefore, this invention provides an elastomeric modified asphalt material and its application method for long-life pavement structures, aiming to optimize the comprehensive performance of modified asphalt, improve its adaptability under extreme climatic conditions, and simplify the production process and reduce production costs, thereby meeting the demands of modern road engineering for high-performance, low-cost modified asphalt materials. Summary of the Invention

[0006] This application provides an elastomeric modified asphalt material for long-life pavement structures and its application method, aiming to improve its comprehensive performance under extreme climatic conditions by optimizing the composition design and preparation process of the modified asphalt, while simplifying the production process and reducing production costs.

[0007] In a first aspect, this application provides a method for preparing elastomeric modified asphalt materials, comprising the following steps: S10: heating the base asphalt to 150 to 170°C to completely melt it into a liquid state; then adding 3% to 5% by mass of an elastomeric polymer, and performing preliminary mixing at a stirring rate of 500 to 800 rpm for a mixing time of 20 to 30 minutes; S20: adding 0.5% to 1.5% by mass of a crosslinking agent and 0.1% to 0.3% by mass of a stabilizer to the above-mentioned mixture, and continuing to stir and mix at a stirring rate of 800 to 1000 rpm for a mixing time of 15 to 25 minutes; S30: degassing the mixed modified asphalt system under vacuum conditions, with the vacuum degree set to -0.08 to -0.1 MPa for a degassing time of 10 to 20 minutes; then cooling to room temperature to obtain the elastomeric modified asphalt material.

[0008] According to this application, in step S10, the elastomeric polymer is a styrene-butadiene-styrene block copolymer (SBS) or a styrene-isoprene-styrene block copolymer (SIS), with a particle size range controlled between 0.5 mm and 2 mm. This elastomeric polymer with a specific particle size range can be uniformly dispersed in the base asphalt, avoiding the occurrence of local agglomeration.

[0009] In some embodiments, in step S20, the crosslinking agent is selected from dicumyl peroxide (DCP) or a sulfur crosslinking agent, with a purity of not less than 98%. The stabilizer is selected from antioxidant 1010 or ultraviolet absorber UV-531, and the ratio of its addition to the crosslinking agent is maintained between 1:5 and 1:10. This combination design can effectively delay the aging process of modified asphalt during long-term use and improve its weather resistance.

[0010] In some embodiments, in step S30, after degassing, the viscosity of the modified asphalt material is controlled between 150 and 300 Pascal-seconds. This viscosity range ensures good flowability during construction while also ensuring rapid shaping of the material after paving.

[0011] Secondly, this application also provides a method for applying an elastomeric modified asphalt material for long-life pavement structures, comprising the following steps: A10: heating the elastomeric modified asphalt material prepared above to 140 to 160°C to restore it to a liquid state; then mixing it with aggregate at a mass ratio of 1:3 to 1:5, with a stirring rate of 600 to 800 rpm and a stirring time of 10 to 15 minutes; A20: spreading the mixed asphalt concrete onto the subgrade surface, with a spreading thickness controlled between 5 cm and 10 cm; the ambient temperature during spreading should not be lower than 10°C to ensure the fluidity and uniformity of the material; A30: compacting the spread asphalt concrete, with a compaction force controlled between 20 tons and 30 tons, and compaction times not less than 3 times; then naturally cooling to room temperature to form a complete pavement structure.

[0012] According to this application, in step A10, the aggregate gradation ratio is designed as follows: fine powder with a particle size less than 0.075 mm accounts for 5% to 10% of the total mass; small particles with a particle size of 0.075 mm to 2.36 mm account for 20% to 30% of the total mass; medium particles with a particle size of 2.36 mm to 9.5 mm account for 30% to 40% of the total mass; and large particles with a particle size of 9.5 mm to 19 mm account for 20% to 30% of the total mass. This gradation design can significantly improve the density and crack resistance of asphalt concrete.

[0013] In some embodiments, in step A20, a double-layer paving technique is used during the paving process, with the bottom layer having a thickness of 3 to 5 centimeters and the top layer having a thickness of 2 to 5 centimeters. The double-layer paving technique can further enhance the load-bearing capacity and deformation resistance of the pavement structure.

[0014] In some embodiments, in step A30, the compaction process involves initial compaction with a vibratory roller, secondary compaction with a static roller, and final compaction with a pneumatic tire roller. This multi-stage compaction process effectively eliminates voids within asphalt concrete, improving the overall strength and stability of the pavement.

[0015] Thirdly, this application also provides an optimized design for the low-temperature crack resistance of the elastomer-modified asphalt material. Specifically, this includes the following technical means: B10: Introducing a toughening agent with a mass fraction of 0.2% to 0.5% into the elastomer-modified asphalt material, the toughening agent being selected from polyurethane elastomers or epoxy resins; B20: Further improving its low-temperature toughness by incorporating nano-silica particles with a mass fraction of 0.1% to 0.3% into the modified asphalt material; B30: During the preparation of the modified asphalt material, controlling the melt index of the elastomer polymer between 1 gram per 10 minutes and 5 grams per 10 minutes to ensure that it can still maintain a certain degree of flexibility under low-temperature conditions.

[0016] According to this application, in step B10, the mass ratio of the toughening agent to the elastomer polymer is maintained between 1:10 and 1:20. This ratio design can significantly improve the low-temperature crack resistance of the modified asphalt material without significantly affecting its high-temperature performance.

[0017] In some embodiments, in step B20, the particle size of the nano-silica particles is controlled between 10 nanometers and 50 nanometers. Nanoparticles of this size range can be uniformly dispersed in the modified asphalt, forming a stable network structure, thereby enhancing the material's low-temperature toughness and crack resistance.

[0018] Fourthly, this application includes a specific optimization design for the aging resistance of modified asphalt materials. Specifically, this includes the following technical means: C10: Adding 0.2% to 0.5% by mass of a light stabilizer to the elastomeric modified asphalt material; the light stabilizer is selected from hindered amine light stabilizers or benzotriazole UV absorbers; C20: Further delaying the thermo-oxidative aging process of the material during long-term use by adding 0.1% to 0.3% by mass of an antioxidant to the modified asphalt material; C30: Strictly controlling the heating temperature to not exceed 180℃ during the preparation of the modified asphalt material to avoid material performance degradation due to overheating.

[0019] According to this application, in step C10, the mass ratio of the light stabilizer to the antioxidant is maintained between 1:1 and 1:2. This ratio design can effectively work synergistically to extend the service life of the modified asphalt material under ultraviolet radiation and high-temperature environments.

[0020] In some embodiments, in step C20, the antioxidant is selected from phenolic antioxidants or phosphite antioxidants, with a purity of not less than 99%. High-purity antioxidants can significantly improve the antioxidant properties of modified asphalt materials and reduce performance degradation during long-term use.

[0021] Fifthly, this application provides specific performance indicators for an elastomeric modified asphalt material used in long-life pavement structures. The material exhibits a softening point of not less than 60°C at high temperatures, a brittle point of not more than -20°C at low temperatures, a penetration range of 40 to 80 units, and a ductility of not less than 50 cm at 15°C. These performance indicators demonstrate that the modified asphalt material exhibits excellent performance in both high-temperature stability and low-temperature crack resistance.

[0022] In some embodiments, the anti-aging properties of the elastomeric modified bitumen material are verified by accelerated aging tests. After 100 hours of aging testing, its mass loss rate does not exceed 0.5%, its penetration ratio is not less than 70%, and its ductility retention rate is not less than 60%. These data indicate that the material has good weather resistance and anti-aging properties during long-term use.

[0023] Sixthly, this application also provides an economic analysis of an elastomeric modified asphalt material for long-life pavement structures. By optimizing the raw material ratio and simplifying the production process, the production cost of this material is reduced by 10% to 15% compared to traditional modified asphalt materials. Furthermore, due to its superior performance, it can significantly reduce pavement maintenance frequency, thereby further reducing the overall cost over its entire life cycle.

[0024] In summary, the elastomeric modified asphalt material and its application method provided in this application solve the problems of insufficient performance stability, poor low-temperature crack resistance, poor aging resistance, and complex production process in the prior art by optimizing the formula design, improving the production process, and enhancing the performance indicators. This meets the needs of modern road engineering for high-performance and low-cost modified asphalt materials. Detailed Implementation

[0025] The embodiments or implementations described in this specification adopt a progressive approach, with each embodiment focusing on its differences from other embodiments. In the description of this specification, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with an implementation or example that are included in at least one implementation or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same implementation or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more implementations or examples.

[0026] In a first aspect, this application provides a method for preparing elastomeric modified asphalt materials, comprising the following steps: S10: heating the base asphalt to 150 to 170°C until it is completely melted into a liquid state; then adding 3% to 5% by mass of an elastomeric polymer, and performing preliminary mixing at a stirring rate of 500 to 800 rpm for a mixing time of 20 to 30 minutes. The base asphalt can be No. 70 or No. 90 road petroleum asphalt, with a penetration range of 60 to 80 units and a softening point not lower than 45°C. The elastomeric polymer is styrene-butadiene-styrene block copolymer (SBS) or styrene-isoprene-styrene block copolymer (SIS), with a particle size range of 0.5 mm to 2 mm. The specific particle size distribution can be adjusted using sieving equipment to ensure that the elastomeric polymer is uniformly dispersed in the base asphalt. The stirring rate needs to be matched with the particle size of the elastomeric polymer; for larger particle sizes, the stirring rate should be appropriately increased to avoid local agglomeration.

[0027] S20: Add 0.5% to 1.5% (by mass) of crosslinking agent and 0.1% to 0.3% (by mass) of stabilizer to the above mixture system, and continue stirring at a speed of 800 to 1000 rpm for 15 to 25 minutes. The crosslinking agent is selected from dicumyl peroxide (DCP) or sulfur crosslinking agent, with a purity of not less than 98%. The stabilizer is selected from antioxidant 1010 or ultraviolet absorber UV-531, and its addition ratio to the crosslinking agent is maintained between 1:5 and 1:10. The amount of crosslinking agent added needs to be adjusted according to the type and content of the elastomer polymer. For example, when using SBS, the amount of crosslinking agent added should be controlled between 0.8% and 1.2%; when using SIS, the amount of crosslinking agent added should be controlled between 0.5% and 0.8%. The amount of stabilizer added needs to be optimized according to the ultraviolet intensity and temperature conditions of the construction environment to ensure the performance stability of the modified asphalt material during long-term use.

[0028] S30: The mixed modified asphalt system is degassed under vacuum conditions, with a vacuum level set to -0.08 to -0.1 MPa and a degassed time of 10 to 20 minutes. It is then cooled to room temperature to obtain the elastomeric modified asphalt material. The purpose of degassed treatment is to remove air bubbles and volatile components from the modified asphalt system to improve the material's density and stability. The cooling process must be carried out in a natural environment, and the cooling rate should not be too fast to avoid microcracks forming inside the material due to thermal stress. The viscosity of the final modified asphalt material is controlled between 150 and 300 Pascal-seconds. This viscosity range ensures good flowability during construction while also ensuring rapid shaping after paving.

[0029] Secondly, this application also provides a method for applying an elastomeric modified asphalt material for long-life pavement structures, comprising the following steps: A10: Heating the elastomeric modified asphalt material prepared above to 140 to 160°C to restore it to a liquid state; then mixing it with aggregate at a mass ratio of 1:3 to 1:5, with a stirring rate of 600 to 800 rpm and a stirring time of 10 to 15 minutes. The aggregate gradation is designed as follows: fine powder with a particle size less than 0.075 mm accounts for 5% to 10% of the total mass, small particles with a particle size of 0.075 mm to 2.36 mm account for 20% to 30% of the total mass, medium particles with a particle size of 2.36 mm to 9.5 mm account for 30% to 40% of the total mass, and large particles with a particle size of 9.5 mm to 19 mm account for 20% to 30% of the total mass. The mud content of the aggregate needs to be controlled below 1% to avoid affecting the bonding performance of the asphalt concrete. The mixing rate needs to be adjusted according to the aggregate particle size distribution. Larger aggregates require a higher mixing rate to ensure uniform mixing.

[0030] A20: The mixed asphalt concrete is spread onto the roadbed surface, with a thickness controlled between 5 and 10 centimeters. The ambient temperature during paving should not be lower than 10°C to ensure the fluidity and uniformity of the material. A double-layer paving technique can be used, with a base layer thickness of 3 to 5 centimeters and an upper layer thickness of 2 to 5 centimeters. The specific implementation of the double-layer paving technique can be adjusted according to the road surface's load-bearing requirements. For example, for heavy traffic sections, the base layer thickness can be appropriately increased to 4 to 6 centimeters to improve the road surface's resistance to deformation. The selection of paving equipment needs to be optimized based on the construction scale and site conditions. Tracked pavers are recommended to improve the smoothness and uniformity of the paving.

[0031] A30: After paving, the asphalt concrete is compacted with a compaction force controlled between 20 and 30 tons, and the compaction is repeated at least three times. It is then allowed to cool naturally to room temperature to form a complete pavement structure. The compaction process uses a vibratory roller for initial compaction, a static roller for secondary compaction, and a pneumatic tire roller for final compaction. During the initial compaction stage, the vibration frequency should be controlled between 30 Hz and 50 Hz, and the amplitude between 0.5 mm and 1 mm to effectively reduce the porosity within the asphalt concrete. During the secondary compaction stage, the compaction force should be gradually increased, ideally from 20 tons to 25 tons, to avoid material segregation caused by a single high compaction force. The pneumatic tire roller used in the final compaction stage should be equipped with wide tires to improve compaction uniformity and surface smoothness.

[0032] Thirdly, this application provides an optimized design for the low-temperature crack resistance of the elastomeric modified asphalt material, including the following technical means: B10: Introducing a toughening agent with a mass fraction of 0.2% to 0.5% into the elastomeric modified asphalt material. The toughening agent is selected from polyurethane elastomers or epoxy resins. The mass ratio of the toughening agent to the elastomer polymer is maintained between 1:10 and 1:20. The toughening agent needs to be introduced by pre-dissolving, that is, dissolving the toughening agent in an appropriate amount of solvent and then slowly adding it to the modified asphalt system to ensure its uniform dispersion.

[0033] B20: By incorporating 0.1% to 0.3% by mass of nano-silica particles into modified asphalt materials, their low-temperature toughness is further improved. The particle size range of the nano-silica particles is controlled between 10 nanometers and 50 nanometers. The addition method can be carried out using a high-speed shearing device with a shearing rate of 3000 to 5000 revolutions per minute and a shearing time of 5 to 10 minutes.

[0034] B30: During the preparation of modified bitumen materials, the melt index of the elastomer polymer should be controlled between 1 gram per 10 minutes and 5 grams per 10 minutes to ensure that it maintains a certain degree of flexibility under low-temperature conditions. The melt index should be determined according to ASTM D1238 standard, with a test temperature of 190°C and a load of 2.16 kg.

[0035] Fourthly, this application includes a specific optimization design for the aging resistance of modified asphalt materials, including the following technical means: C10: A light stabilizer with a mass fraction of 0.2% to 0.5% is incorporated into the elastomeric modified asphalt material. The light stabilizer is selected from hindered amine light stabilizers or benzotriazole UV absorbers. The mass ratio of the added light stabilizer to the antioxidant is maintained between 1:1 and 1:2. The introduction of the light stabilizer needs to be carried out through premixing, that is, the light stabilizer is mixed evenly with a small amount of base asphalt before being added to the modified asphalt system.

[0036] C20: By adding 0.1% to 0.3% by mass of an antioxidant to modified asphalt materials, the thermo-oxidative aging process of the materials during long-term use is further delayed. The antioxidant should be a phenolic antioxidant or a phosphite antioxidant with a purity of not less than 99%. The method of adding the antioxidant should be similar to that of adding a light stabilizer, requiring premixing to ensure uniform dispersion.

[0037] C30: During the preparation of modified bitumen materials, the heating temperature must be strictly controlled to not exceed 180℃ to avoid material performance degradation due to overheating. The heating temperature must be monitored in real time using online temperature monitoring equipment to ensure that the temperature fluctuation range throughout the entire preparation process does not exceed ±5℃.

[0038] Fifthly, this application provides specific performance indicators for an elastomeric modified asphalt material used in long-life pavement structures. The softening point under high-temperature conditions is not lower than 60°C, the brittle point under low-temperature conditions is not higher than -20°C, the penetration range is 40 to 80 units, and the ductility at 15°C is not lower than 50 cm. These performance indicators must be measured according to relevant national standards, specifically, the softening point must be measured according to ASTM D36, the brittle point according to ASTM D97, the penetration according to ASTM D5, and the ductility according to ASTM D113.

[0039] Sixthly, this application also provides an economic analysis of an elastomeric modified asphalt material for long-life pavement structures. By optimizing the raw material ratio and simplifying the production process, the production cost of this material is reduced by 10% to 15% compared to traditional modified asphalt materials. Furthermore, due to its superior performance, it can significantly reduce pavement maintenance frequency, thereby further reducing the overall cost over its entire life cycle.

[0040] The following describes embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all conventional products that can be obtained commercially.

[0041] Example 1, S10: 70# road petroleum asphalt was heated to 160°C, then 4% (by mass) of SBS elastomer polymer was added. Initial mixing was performed at a stirring speed of 600 rpm for 25 minutes. S20: 1% (by mass) of dicumyl peroxide (DCP) and 0.2% (by mass) of antioxidant 1010 were added to the above mixture. Mixing continued at a stirring speed of 900 rpm for 20 minutes. S30: The modified asphalt system was degassed under a vacuum of -0.09 MPa for 15 minutes, then cooled to room temperature to obtain the elastomer-modified asphalt material.

[0042] Example 2, S10: 90# road petroleum asphalt was heated to 155°C, then 5% (by mass) of SIS elastomer polymer was added. Initial mixing was performed at a stirring speed of 700 rpm for 20 minutes. S20: 1.2% (by mass) of sulfur crosslinking agent and 0.3% (by mass) of UV absorber UV-531 were added to the above mixture. Mixing continued at a stirring speed of 850 rpm for 25 minutes. S30: The modified asphalt system was degassed under a vacuum of -0.1 MPa for 20 minutes, then cooled to room temperature to obtain the elastomer-modified asphalt material.

[0043] Example 3S10: 70# road petroleum asphalt was heated to 165°C, then 3.5% (by mass) of SBS elastomer polymer was added. Initial mixing was carried out at a stirring speed of 800 rpm for 30 minutes. S20: 0.8% (by mass) of dicumyl peroxide (DCP) and 0.1% (by mass) of antioxidant 1010 were added to the above mixture. Mixing continued at a stirring speed of 1000 rpm for 15 minutes. S30: The modified asphalt system was degassed under a vacuum of -0.08 MPa for 10 minutes, then cooled to room temperature to obtain the elastomer-modified asphalt material.

[0044] Comparative Example 1S10: 70# road petroleum asphalt was heated to 160°C, then 4% (w / w) of SBS elastomer polymer was added. Initial mixing was carried out at a stirring speed of 600 rpm for 25 minutes. S20: 1% (w / w) of dicumyl peroxide (DCP) was added to the above mixture, and stirring was continued at 900 rpm for 20 minutes. No stabilizer was added. S30: The modified asphalt mixture was degassed under a vacuum of -0.09 MPa for 15 minutes, then cooled to room temperature to obtain the elastomer-modified asphalt material.

[0045] Comparative Example 2S10: 90# road petroleum asphalt was heated to 155°C, then 5% (w / w) of SIS elastomer polymer was added. Initial mixing was carried out at a stirring speed of 700 rpm for 20 minutes. S20: 1.2% (w / w) of sulfur crosslinking agent was added to the above mixture, and mixing continued at a stirring speed of 850 rpm for 25 minutes. No stabilizer was added. S30: The modified asphalt mixture was degassed under a vacuum of -0.1 MPa for 20 minutes, then cooled to room temperature to obtain the elastomer-modified asphalt material.

[0046] The performance of the elastomeric modified asphalt materials obtained in the above embodiments and comparative examples was tested, and the results are shown in the table below:

[0047] As shown in the table above, the elastomeric modified bitumen material obtained in this application has a higher softening point, a lower brittle point, higher ductility, and lower production cost compared to the comparative examples. Comparative Examples 1 and 2 did not contain stabilizers, resulting in a significant decrease in their low-temperature performance and ductility, as well as a lower reduction in production cost.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for preparing an elastomeric modified asphalt material for long-life pavement structures, characterized in that, The process includes the following steps: S10: Heating the base asphalt to 150°C to 170°C until it is completely melted into a liquid state; then adding 3% to 5% by mass of an elastomer polymer, and performing preliminary mixing at a stirring speed of 500 rpm to 800 rpm for a mixing time of 20 to 30 minutes; S20: Adding 0.5% to 1.5% by mass of a crosslinking agent and 0.1% to 0.3% by mass of a stabilizer to the above mixture, and continuing to stir and mix at a stirring speed of 800 rpm to 1000 rpm for a mixing time of 15 to 25 minutes; S30: Degassing the mixed modified asphalt system under vacuum conditions, with the vacuum level set to -0.08 MPa to -0.1 MPa for a degassing time of 10 to 20 minutes; then cooling to room temperature to obtain the elastomer-modified asphalt material.

2. The method according to claim 1, characterized in that, In step S10, the elastomer polymer is selected from styrene-butadiene-styrene block copolymer or styrene-isoprene-styrene block copolymer, and its particle size ranges from 0.5 mm to 2 mm.

3. The method according to claim 1, characterized in that, In step S20, the crosslinking agent is selected from dicumyl peroxide or sulfur crosslinking agent, and its purity is not less than 98%; the stabilizer is selected from antioxidant 1010 or ultraviolet absorber UV-531, and the mass ratio of stabilizer to crosslinking agent is 1:5 to 1:

10.

4. The method according to claim 1, characterized in that, In step S30, after degassing, the viscosity of the modified asphalt material is between 150 Pascals per second and 300 Pascals per second.

5. A method for applying an elastomeric modified asphalt material to a long-life pavement structure, characterized in that, The process includes the following steps: A10: Heating the elastomeric modified asphalt material prepared according to any one of claims 1 to 4 to 140°C to 160°C to restore it to a liquid state; then mixing it with aggregate at a mass ratio of 1:3 to 1:5, with a stirring rate of 600 rpm to 800 rpm and a stirring time of 10 to 15 minutes; A20: Spreading the mixed asphalt concrete onto the roadbed surface with a spreading thickness of 5 cm to 10 cm; the ambient temperature during spreading is not lower than 10°C; A30: Compacting the spread asphalt concrete with a compaction force of 20 to 30 tons and at least 3 compaction cycles; then allowing it to cool naturally to room temperature to form a complete pavement structure.

6. The method according to claim 5, characterized in that, In step A10, the aggregate gradation ratio is designed as follows: fine powder with a particle size of less than 0.075 mm accounts for 5% to 10% of the total mass, small particles with a particle size of 0.075 mm to 2.36 mm account for 20% to 30% of the total mass, medium particles with a particle size of 2.36 mm to 9.5 mm account for 30% to 40% of the total mass, and large particles with a particle size of 9.5 mm to 19 mm account for 20% to 30% of the total mass.

7. The method according to claim 5, characterized in that, In step A20, a double-layer paving technique is used, with the bottom layer paving thickness being 3 to 5 centimeters and the top layer paving thickness being 2 to 5 centimeters.

8. The method according to claim 5, characterized in that, In step A30, the compaction process is carried out sequentially by a vibratory roller for initial compaction, a static roller for secondary compaction, and a pneumatic tire roller for final compaction.

9. The method according to claim 1, characterized in that, It also includes introducing a toughening agent with a mass fraction of 0.2% to 0.5% into the elastomer-modified bitumen material, the toughening agent being selected from polyurethane elastomers or epoxy resins; incorporating nano-silica particles with a mass fraction of 0.1% to 0.3% and a particle size range of 10 nanometers to 50 nanometers; and controlling the melt index of the elastomer polymer to be 1 gram per 10 minutes to 5 grams per 10 minutes.

10. An elastomeric modified asphalt material for long-life pavement structures, characterized in that, Prepared according to the method according to any one of claims 1 to 9.

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