Asphalt concrete with both anti-skid and noise reduction properties and a preparation method thereof

Abstract

This application relates to the technical field of asphalt concrete, specifically disclosing an asphalt concrete with both anti-skid and noise-reducing properties, and its preparation method. The asphalt concrete with both anti-skid and noise-reducing properties comprises the following components by weight: 72-82 parts of high-polish coarse aggregate, 10-18 parts of fine aggregate, 4-8 parts of composite filler, 2-6 parts of roughened elastic noise-reducing particles, 0.2-0.6 parts of fiber stabilizer, and 5.5-7.2 parts of modified asphalt. In this application, the high-polish coarse aggregate forms a stable rough surface, ensuring the depth of the road surface's macrostructure and long-term anti-skid properties. The roughened elastic noise-reducing particles reduce the impact and vibration propagation between the tire and the road surface, lowering noise. The composite filler and fiber stabilizer construct continuous but controlled interconnected pores, absorbing mid-to-high frequency noise while preventing particle shedding, scattering, and strength attenuation, thus resulting in concrete with both anti-skid and noise-reducing properties.

Description

Technical Field

[0001] This application relates to the technical field of asphalt concrete, and in particular to an asphalt concrete with both anti-skid and noise-reducing properties, and a method for preparing the same. Background Technology

[0002] Asphalt concrete, with its outstanding advantages such as smooth surface, comfortable driving, convenient construction, and low maintenance cost, has been widely used in pavement projects for various transportation infrastructures, including highways, urban arterial roads, tunnels, and bridges. It is a core material for ensuring traffic safety and improving the driving experience. Currently, the preparation technology of asphalt concrete is relatively mature. It mainly uses asphalt as a binder, combined with coarse aggregate, fine aggregate, mineral powder, and various modifiers and admixtures. By optimizing the aggregate gradation and improving the mixing and compaction process, the core indicators such as pavement strength, durability, and resistance to high and low temperatures can be improved. At the same time, in order to meet the needs of different usage scenarios, the industry has gradually carried out optimization attempts for specific properties such as skid resistance and noise reduction. For example, using aggregates with rough surfaces to improve skid resistance and adjusting the pore structure of the mixture to reduce driving noise can basically meet the basic usage requirements of conventional traffic scenarios.

[0003] With the rapid development of the transportation industry, vehicle speeds are constantly increasing and traffic flow is continuously growing. Especially in urban core sections, tunnels, and areas around schools, higher requirements are placed on the skid resistance and noise reduction of asphalt concrete pavements. However, existing technologies have obvious technical shortcomings in balancing these two properties. Existing asphalt concrete often struggles to achieve a synergistic improvement in skid resistance and noise reduction. In most cases, there is a contradiction: "improved skid resistance leads to decreased noise reduction, and optimized noise reduction results in insufficient skid resistance." If large-diameter, high-angular aggregates are used to increase pavement roughness to enhance skid resistance, it will lead to an unreasonable pavement porosity, increasing the impact friction between tires and the road surface during driving and significantly increasing noise. If the driving noise is reduced by decreasing the aggregate size and increasing the density of the mixture, the pavement surface will become too smooth, significantly reducing skid resistance and easily causing traffic safety hazards such as skidding in rainy weather. In addition, some targeted modified agents or processes have problems such as high cost, difficult construction, and poor performance stability, which cannot meet the actual needs of high-demand traffic scenarios where the pavement has excellent skid resistance, noise reduction performance, and long-term stable service. Summary of the Invention

[0004] In order to make concrete have both excellent anti-skid and noise reduction properties, this application provides an asphalt concrete with both anti-skid and noise reduction properties and a method for preparing the same.

[0005] Firstly, this application provides an asphalt concrete that combines anti-skid and noise-reducing properties, employing the following technical solution: An asphalt concrete with both anti-skid and noise reduction properties, wherein the raw materials of the asphalt concrete include the following components in parts by weight: 72-82 parts of high polishing value coarse aggregate, 10-18 parts of fine aggregate, 4-8 parts of composite filler, 2-6 parts of roughened elastic noise-reducing particles, 0.2-0.6 parts of fiber stabilizer, and 5.5-7.2 parts of modified asphalt.

[0006] By adopting the above technical solutions, a stable rough surface is formed by high polishing value coarse aggregate, which ensures the depth of the road surface macrostructure and long-term anti-skid properties. Roughened elastic noise-reducing particles reduce the impact and vibration transmission between the tire and the road surface, thereby reducing noise. Composite fillers and fiber stabilizers construct continuous but controlled interconnected pores to absorb mid-to-high frequency noise, while preventing particle shedding, scattering, and strength attenuation, so that the resulting concrete has both anti-skid and noise-reducing properties.

[0007] In one specific implementation, the method for preparing the roughened elastic noise-reducing particles includes the following steps: Preheat the rubber granules to 70-90℃, spray with adhesive material, then stir at 80-110℃ for 3-8 minutes, add calcined bauxite powder, mix and coat at 80-100℃ for 5-10 minutes, cool, and obtain roughened elastic noise-reducing granules.

[0008] By adopting the above technical solution, the rubber particles are preheated and then coated with adhesive material, and further coated with calcined bauxite powder, so that the surface of the rubber particles forms a "elastic core-rough outer layer" structure. The rubber particles can absorb and dissipate the impact energy under vehicle load, reducing road noise; the calcined bauxite powder gives the particle surface high roughness and wear resistance, thereby avoiding the problem of reduced anti-skid performance caused by direct exposure of elastic material, thus achieving a synergistic balance between noise reduction and anti-skid performance.

[0009] In one specific implementation, the weight ratio of the rubber particles to the calcined bauxite powder is 85:(12-16), and the weight ratio of the binder to the rubber particles is (5-6):100.

[0010] By adopting the above technical solution, and controlling the proportions of rubber particles, calcined bauxite powder, and binder within a specific range, the roughened elastic noise-reducing particles can balance surface roughness, particle integrity, and coating stability. Among these, the appropriate amount of binder ensures that the calcined bauxite powder adheres firmly to the surface of the rubber particles while avoiding excessive binder that would cover the surface and reduce roughness, and also avoids insufficient binder that would cause the powder to fall off easily. This results in a better balance between the obtained particles and their anti-slip performance, noise reduction performance, and durability.

[0011] In one specific implementation, the method for preparing the adhesive material includes the following steps: Heat the base asphalt to 145-155℃ and hold for 20-30 minutes to fully melt it and make it fluid. Add aromatic oil under stirring and mix. Then raise the temperature to 165-175℃ and slowly add SBS under stirring. After adding, shear disperse the SBS. Then maintain the system at 175-185℃ and continue stirring for 40-90 minutes to obtain system A. Add the tackifying resin to system A at 170-180℃ and continue stirring for 20-40 minutes. Then adjust the temperature to 165-175℃, add the stabilizer and antioxidant in sequence, stir for 10-20 minutes, and finally cure at 165-175℃ for 20-40 minutes. Filter the material to obtain the adhesive material.

[0012] By adopting the above technical solution, the bonding material is prepared stepwise using base asphalt, aromatic oil, SBS, tackifying resin, stabilizer, and antioxidant. On the one hand, SBS can fully swell in the asphalt system and form a stable modified network structure, improving the elasticity, toughness, and high-temperature stability of the bonding material. On the other hand, the tackifying resin can enhance the adhesion of the bonding material to rubber particles and calcined bauxite powder, while the stabilizer and antioxidant are beneficial to improving the storage stability and anti-aging performance of the system, thereby ensuring the coating effect and long-term service stability of the roughened elastic noise-reducing particles.

[0013] In one specific implementation, in the preparation step of the adhesive material, the weight ratio of the base asphalt, aromatic oil, SBS, tackifying resin, stabilizer, and antioxidant is 100:(2-4):(4-6):(1-3):(0.1-0.2):(0.1-0.3).

[0014] By adopting the above technical solution, further limiting the proportions of base asphalt, aromatic oil, SBS, tackifying resin, stabilizer, and antioxidant, the resulting bonding material can simultaneously possess suitable fluidity, adhesion, elasticity, and thermal stability. This facilitates uniform spraying onto the surface of rubber particles and promotes stable adhesion of subsequent calcined bauxite powder, avoiding problems such as uneven coating, particle clumping, or surface peeling, thereby further improving the preparation stability and application effect of roughened elastic noise-reducing particles.

[0015] In one specific implementation, the composite filler comprises a mixture of limestone powder, diatomaceous earth, and hydrated lime.

[0016] By adopting the above technical solutions, limestone powder can play the role of conventional filling and improving gradation, diatomaceous earth can enhance the absorption and dissipation of noise through its porous structure, and hydrated lime can help improve the adhesion between asphalt and mineral aggregates and improve the resistance to water damage. The synergistic effect of the three is conducive to improving the noise reduction performance while ensuring the structural stability and durability of the mixture.

[0017] In one specific implementation, the fiber stabilizer comprises a mixture of basalt fiber and lignin fiber.

[0018] By adopting the above technical solution, a composite fiber stabilizer composed of basalt fiber and lignin fiber is used. Basalt fiber can enhance the binding effect and crack resistance of the internal skeleton of asphalt concrete, while lignin fiber can adsorb some asphalt, inhibit asphalt flow, and improve the stability of the asphalt film. The two work together to improve the overall strength, anti-loosening performance and anti-scattering performance of the mixture, thereby ensuring the long-term stable existence of the structure with both anti-skid and noise reduction performance.

[0019] In one specific implementation, the high-polish coarse aggregate comprises basalt; and the fine aggregate comprises limestone manufactured sand.

[0020] By adopting the above technical solutions, basalt can provide high hardness, wear resistance and anti-polishing performance, ensuring the long-term skid resistance of the road surface; limestone manufactured sand can optimize the micro-gradation structure and improve the compactness and skeleton stability of the mixture; thus, asphalt concrete can maintain good mixing performance, construction performance and mechanical stability while taking into account skid resistance.

[0021] Secondly, this application provides a method for preparing asphalt concrete that combines anti-skid and noise reduction properties, employing the following technical solution: A method for preparing asphalt concrete with both skid resistance and noise reduction properties includes the following steps: High-polish coarse aggregate and fine aggregate are heated to 170-185℃ and stirred to obtain mixture A. After the composite filler is dried, it is added to mixture A and stirred. Then, fiber stabilizer is added and stirred to obtain mixture B. Add some modified asphalt to mixture B and wet mix for 25-40 seconds. Then add roughened elastic noise-reducing particles and the remaining modified asphalt in sequence, and continue mixing for 20-35 seconds. Discharge the material at 170-175℃ to obtain asphalt concrete.

[0022] By adopting the above technical solution, high-polish value coarse aggregate, fine aggregate, composite filler and fiber stabilizer are first mixed to form a stable mineral skeleton. Then, modified asphalt and roughened elastic noise-reducing particles are added in two stages. On the one hand, this is conducive to the priority formation of a uniform and stable mineral asphalt coating system, ensuring the skeleton structure and foundation strength of the mixture. On the other hand, it can avoid damage to the roughened elastic noise-reducing particles or the coating layer falling off in the early stage of high-intensity mixing, thereby better maintaining its surface rough structure and elastic noise-reducing function, which ultimately helps to improve the skid resistance and noise reduction performance of the obtained asphalt concrete.

[0023] In summary, this application includes at least one of the following beneficial technical effects: In this application, a stable rough surface is formed by high polishing value coarse aggregate, which ensures the depth of the road surface macrostructure and long-term anti-skid properties. Roughened elastic noise-reducing particles reduce the impact and vibration transmission between the tire and the road surface, thereby reducing noise. Composite fillers and fiber stabilizers construct continuous but controlled interconnected pores to absorb mid-to-high frequency noise, while preventing particle shedding, scattering and strength reduction, so that the resulting concrete has both anti-skid and noise-reducing properties. In this application, rubber granules are preheated and then coated with adhesive material, and further coated with calcined bauxite powder, so that the surface of the rubber granules forms a "elastic core-rough outer layer" structure. The rubber granules can absorb and dissipate the impact energy under vehicle load, reducing road noise; while the calcined bauxite powder gives the granule surface high roughness and wear resistance, thereby avoiding the problem of reduced anti-skid performance caused by direct exposure of elastic material, thus achieving a synergistic balance between noise reduction and anti-skid performance. The method in this application first mixes high-polish-value coarse aggregate, fine aggregate, composite filler, and fiber stabilizer to form a stable mineral skeleton. Then, modified asphalt and roughened elastic noise-reducing particles are added in two stages. On the one hand, this facilitates the formation of a uniform and stable mineral asphalt coating system, ensuring the skeleton structure and foundation strength of the mixture. On the other hand, it avoids damage to the roughened elastic noise-reducing particles or peeling of the coating layer during the initial stage of high-intensity mixing, thereby better maintaining its surface rough structure and elastic noise-reducing function. Ultimately, this helps to improve the skid resistance and noise reduction performance of the resulting asphalt concrete. Detailed Implementation

[0024] The present application will be further described in detail below with reference to the embodiments.

[0025] All raw materials used in the examples are commercially available. The modified asphalt is SBS asphalt supplied by Nanjing Refinery Co., Ltd.; the base asphalt is 70# base asphalt; the SBS type is D-KX401; the tackifying resin is C5 petroleum resin; the stabilizer is sulfur powder; the antioxidant is antioxidant 1010; the aromatic oil is yld-zy; the rubber granules are recycled waste tire rubber granules with a particle size of 0.5-2mm; the limestone mineral powder has a particle size of 0.1-0.3mm; the limestone manufactured sand has a particle size of 3-5mm; the basalt has a particle size of 10-20mm; the diatomaceous earth, hydrated lime, and calcined bauxite powder have a particle size of 1-3mm; the basalt fiber has a length of 5-6mm; and the lignin fiber is type KLW-005. Preparation Example

[0026] Preparation Example 1 Preparation Example 1 provides a method for preparing roughened elastic noise-reducing particles, comprising the following steps: The base asphalt was heated to 150°C and held for 25 minutes to fully melt it and bring it into a fluid state. Aromatic oil was added at 400 rpm and mixed for 15 minutes. Then the temperature was raised to 170°C and SBS was slowly added under stirring. After addition, the mixture was sheared and dispersed at 4000 rpm for 45 minutes. The system was then maintained at 180°C and stirred at 400 rpm for 60 minutes to obtain system A. Add tackifying resin to system A at 175℃ and continue stirring for 30 minutes. Then adjust the temperature to 170℃, add stabilizer and antioxidant in sequence, stir for 15 minutes, and finally mature at 170℃ for 30 minutes. Filter the material to obtain the bonding material with a filtration mesh size of 40-60 mesh. The weight ratio of matrix asphalt, aromatic oil, SBS, tackifying resin, stabilizer, and antioxidant is 100:2:4:1:0.1:0.1. The rubber granules are preheated to 80°C, coated with adhesive material, stirred at 95°C for 5 minutes, calcined bauxite powder is added, and mixed and coated at 90°C for 8 minutes. After cooling to room temperature, roughened elastic noise-reducing granules are obtained. The weight ratio of rubber granules to calcined bauxite powder is 85:12, and the weight ratio of adhesive material to rubber granules is 5:100.

[0027] Preparation Example 2 The difference between Preparation Example 2 and Preparation Example 1 is that, in Preparation Example 2, tackifying resin was added to system A at 175°C, and stirring was continued for 30 min. Then, the temperature was adjusted to 170°C, and stabilizer and antioxidant were added sequentially. The mixture was stirred for 15 min, and finally cured at 170°C for 30 min. The mixture was then filtered to obtain a bonding material with a mesh size of 40-60 mesh. The weight ratio of the base asphalt, aromatic oil, SBS, tackifying resin, stabilizer, and antioxidant was 100:3:5:2:0.15:0.2. The rubber granules were preheated to 80°C, coated with adhesive material, stirred at 95°C for 5 minutes, then calcined bauxite powder was added, and mixed and coated at 90°C for 8 minutes. After cooling to room temperature, roughened elastic noise-reducing granules were obtained. The weight ratio of rubber granules to calcined bauxite powder was 85:14, and the weight ratio of adhesive material to rubber granules was 5.5:100. The remaining steps were the same as in Preparation Example 1.

[0028] Preparation Example 3 The difference between Preparation Example 3 and Preparation Example 1 is that, in Preparation Example 3, tackifying resin was added to system A at 175°C, and stirring was continued for 30 min. Then, the temperature was adjusted to 170°C, and stabilizer and antioxidant were added sequentially. The mixture was stirred for 15 min, and finally cured at 170°C for 30 min. The mixture was then filtered to obtain a bonding material with a mesh size of 40-60 mesh. The weight ratio of the base asphalt, aromatic oil, SBS, tackifying resin, stabilizer, and antioxidant was 100:4:6:3:0.2:0.3. The rubber granules were preheated to 80°C, coated with adhesive material, and then stirred at 95°C for 5 minutes. Calcined bauxite powder was added, and the mixture was mixed and coated at 90°C for 8 minutes. The mixture was then cooled to room temperature to obtain roughened elastic noise-reducing granules. The weight ratio of rubber granules to calcined bauxite powder was 85:16, and the weight ratio of adhesive material to rubber granules was 6:100. The remaining steps were the same as in Preparation Example 1. Example

[0029] Example 1 Example 1 provides a method for preparing asphalt concrete that combines anti-skid and noise reduction properties, comprising the following steps: 72 kg of high-polish coarse aggregate and 10 kg of fine aggregate were heated to 178°C and stirred to obtain mixture A. 4 kg of dried composite filler was added to mixture A and stirred for 15 seconds. Then, 0.2 kg of fiber stabilizer was added and stirred for 8 seconds to obtain mixture B. The high-polish coarse aggregate was basalt; the fine aggregate was limestone manufactured sand; the composite filler was a mixture of limestone ore powder, diatomaceous earth, and hydrated lime, with a weight ratio of 13:3:2; and the fiber stabilizer was a mixture of basalt fiber and lignin fiber, with a weight ratio of 11:9. Add 4 kg of modified asphalt to mixture B and wet mix for 32 s. Then add 2 kg of roughened elastic noise-reducing particles from Preparation Example 1 and 1.5 kg of modified asphalt in sequence, continue mixing for 28 s, and discharge at 172°C to obtain asphalt concrete.

[0030] Example 2 Example 2 provides a method for preparing asphalt concrete that combines anti-skid and noise reduction properties, including the following steps: 77 kg of high-polish coarse aggregate and 14 kg of fine aggregate were heated to 178°C and stirred to obtain mixture A. 6 kg of dried composite filler was added to mixture A and stirred for 15 seconds. Then, 0.4 kg of fiber stabilizer was added and stirred for 8 seconds to obtain mixture B. The high-polish coarse aggregate was basalt; the fine aggregate was limestone manufactured sand; the composite filler was a mixture of limestone ore powder, diatomaceous earth, and hydrated lime, with a weight ratio of 13:3:2; and the fiber stabilizer was a mixture of basalt fiber and lignin fiber, with a weight ratio of 11:9. Add 4.5 kg of modified asphalt to mixture B and wet mix for 32 s. Then add 4 kg of roughened elastic noise-reducing particles from Preparation Example 1 and 1.5 kg of modified asphalt in sequence, continue mixing for 28 s, and discharge at 172°C to obtain asphalt concrete.

[0031] Example 3 Example 3 provides a method for preparing asphalt concrete that combines anti-skid and noise reduction properties, comprising the following steps: 82 kg of high-polish coarse aggregate and 18 kg of fine aggregate were heated to 178°C and stirred to obtain mixture A. 8 kg of dried composite filler was added to mixture A and stirred for 15 seconds. Then, 0.6 kg of fiber stabilizer was added and stirred for 8 seconds to obtain mixture B. The high-polish coarse aggregate was basalt; the fine aggregate was limestone manufactured sand; the composite filler was a mixture of limestone ore powder, diatomaceous earth, and hydrated lime, with a weight ratio of 13:3:2; and the fiber stabilizer was a mixture of basalt fiber and lignin fiber, with a weight ratio of 11:9. Add 5.4 kg of modified asphalt to mixture B and wet mix for 32 s. Then add 6 kg of roughened elastic noise-reducing particles from Preparation Example 1 and 1.8 kg of modified asphalt in sequence, continue mixing for 28 s, and discharge at 172°C to obtain asphalt concrete.

[0032] Example 4 The difference between Example 4 and Example 2 is that 4.5 kg of modified asphalt was added to mixture B, wet-mixed for 32 seconds, and then 4 kg of roughened elastic noise-reducing particles from Preparation Example 2 and 1.5 kg of modified asphalt were added in sequence. The mixture was stirred for another 28 seconds and discharged at 172°C to obtain asphalt concrete. The remaining steps were the same as in Example 2.

[0033] Example 5 The difference between Example 5 and Example 2 is that 4.5 kg of modified asphalt was added to mixture B, wet-mixed for 32 seconds, and then 4 kg of roughened elastic noise-reducing particles from Preparation Example 3 and 1.5 kg of modified asphalt were added in sequence. The mixture was stirred for another 28 seconds and discharged at 172°C to obtain asphalt concrete. The remaining steps were the same as in Example 2.

[0034] Example 6 The difference between Example 6 and Example 4 is that 77 kg of high-polish coarse aggregate and 14 kg of fine aggregate are heated to 178°C and stirred to obtain mixture A. 6 kg of dried composite filler is added to mixture A and stirred for 15 seconds. Then, 0.4 kg of fiber stabilizer is added and stirred for 8 seconds to obtain mixture B. The high-polish coarse aggregate is basalt; the fine aggregate is limestone manufactured sand; the composite filler is limestone mineral powder; and the fiber stabilizer is a mixture of basalt fiber and lignin fiber with a weight ratio of 11:9. The remaining steps are the same as in Example 4.

[0035] Example 7 The difference between Example 7 and Example 4 is that 77 kg of high-polish coarse aggregate and 14 kg of fine aggregate are heated to 178°C and stirred to obtain mixture A. 6 kg of dried composite filler is added to mixture A and stirred for 15 seconds. Then, 0.4 kg of fiber stabilizer is added and stirred for 8 seconds to obtain mixture B. The high-polish coarse aggregate is basalt; the fine aggregate is limestone manufactured sand; the composite filler is a mixture of diatomaceous earth and hydrated lime with a weight ratio of 3:2; and the fiber stabilizer is a mixture of basalt fiber and lignin fiber with a weight ratio of 11:9. The remaining steps are the same as in Example 4.

[0036] Example 8 The difference between Example 8 and Example 4 is that 77 kg of high-polish coarse aggregate and 14 kg of fine aggregate are heated to 178°C and stirred to obtain mixture A. 6 kg of dried composite filler is added to mixture A and stirred for 15 seconds. Then, 0.4 kg of fiber stabilizer is added and stirred for 8 seconds to obtain mixture B. The high-polish coarse aggregate is basalt; the fine aggregate is limestone manufactured sand; the composite filler is a mixture of limestone ore powder, diatomite, and hydrated lime, with a weight ratio of limestone ore powder, diatomite, and hydrated lime of 13:3:2; and the fiber stabilizer is basalt fiber. The remaining steps are the same as in Example 4.

[0037] Example 9 The difference between Example 9 and Example 4 is that 77 kg of high-polish coarse aggregate and 14 kg of fine aggregate are heated to 178°C and stirred to obtain mixture A. 6 kg of dried composite filler is added to mixture A and stirred for 15 seconds. Then, 0.4 kg of fiber stabilizer is added and stirred for 8 seconds to obtain mixture B. The high-polish coarse aggregate is basalt; the fine aggregate is limestone manufactured sand; the composite filler is a mixture of limestone ore powder, diatomaceous earth, and hydrated lime, with a weight ratio of limestone ore powder, diatomaceous earth, and hydrated lime of 13:3:2; and the fiber stabilizer is lignin fiber. The remaining steps are the same as in Example 4. Comparative Example

[0038] Comparative Example 1 Add 4 kg of modified asphalt to mixture B, wet mix for 32 seconds, then add another 1.5 kg of modified asphalt, continue mixing for 28 seconds, and discharge at 172°C to obtain asphalt concrete; the remaining steps are the same as in Example 1.

[0039] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that 72 kg of high polished coarse aggregate and 10 kg of fine aggregate were heated to 178°C and stirred to obtain mixture A. 4 kg of dried filler was added to mixture A and stirred for 15 seconds to obtain mixture B. The high polished coarse aggregate was basalt; the fine aggregate was limestone manufactured sand; and the filler was limestone mineral powder. The remaining steps were the same as in Example 1. Performance testing experiment

[0040] Skid resistance: The test was conducted according to the relevant provisions of the pendulum method in JTG 3450—2019 "Specifications for Field Testing of Highway Subgrade and Pavement". Each group of asphalt concrete was prepared into plate-shaped specimens. The paving temperature was 165℃, and after curing at room temperature for 24 hours, the specimen surface was cleaned and moistened before testing. Three measuring points were selected for each specimen, and each measuring point was tested five times. The average value was taken, and a temperature correction of 20℃ was applied. The average value of three parallel specimens was then taken as the skid resistance result of the sample, expressed as the pendulum value (BPN).

[0041] Noise reduction performance: Tests were conducted according to GB / T 18696.2—2002 "Measurement of sound absorption coefficient and acoustic impedance in acoustic impedance tubes - Part 2: Transfer function method". Cylindrical specimens were drilled from slab-shaped asphalt concrete samples prepared at a paving temperature of 165℃. The sound absorption coefficients at 250Hz, 500Hz, 1000Hz, and 2000Hz were measured using impedance tubes. The arithmetic mean of the sound absorption coefficients at the four frequency points was taken as the noise reduction coefficient (NRC) of the sample. Three parallel specimens were tested in each group, and the average value was taken as the final result.

[0042] Table 1 Performance test results of asphalt concrete

[0043] Combining Example 1 and Comparative Examples 1-2, the asphalt concrete in Example 1 exhibits good skid resistance and noise reduction properties. This demonstrates that the present application, through the synergistic design of high-polish-value coarse aggregate, roughened elastic noise-reducing particles, composite filler, and fiber stabilizer, can effectively achieve a balance between skid resistance and noise reduction in asphalt concrete.

[0044] In conjunction with Examples 1-3, as the amounts of high-polish coarse aggregate, composite filler, roughened elastic noise-reducing particles, fiber stabilizer, and modified asphalt gradually increase from low to high, the skid resistance value increases from 64 to 71, and the noise reduction coefficient increases from 0.20 to 0.32. This indicates that within the range given in this application, as the amount of roughened elastic noise-reducing particles and composite filler increases, the rough surface structure and the internal energy-absorbing and sound-absorbing structure are further strengthened, thereby simultaneously improving skid resistance and noise reduction performance.

[0045] Combining Examples 2, 4, and 5, Example 4 achieved the best anti-slip value and noise reduction coefficient, reaching 72 and 0.35 respectively. Example 5, while maintaining a high level, showed a slight decrease compared to Example 4. This result indicates that when the proportions of the binder material raw materials, rubber particles, calcined bauxite powder, and binder material are within a suitable range, it is more conducive to forming a stable and appropriately rough "elastic core-rough outer layer" structure. If the coating layer is too thick or the amount of calcined bauxite powder is too high, the particle surface may be excessively covered by the binder material, or the inter-particle structure may become too dense, thus slightly reducing the anti-slip and noise reduction effects.

[0046] Combining Examples 4, 6, and 7, Example 4 uses a composite filler composed of limestone powder, diatomaceous earth, and hydrated lime; Example 6 uses only limestone powder; and Example 7 uses diatomaceous earth and hydrated lime without limestone powder. The data shows that Example 4 has higher anti-slip value and noise reduction coefficient than Examples 6 and 7, indicating that the combination of the three fillers yields the best results. Limestone powder helps improve filling and gradation stability, diatomaceous earth facilitates the formation of sound-absorbing microporous structures, and hydrated lime helps improve interfacial adhesion and water damage resistance. The combination of these three components maintains good skeletal stability and enhances mid-to-high frequency noise dissipation, thus simultaneously improving anti-slip and noise reduction performance. The absence of any one of these components will lead to a decrease in overall performance.

[0047] Combining Examples 4, 8, and 9, Example 4 uses a blend of basalt fiber and lignin fiber, Example 8 uses only basalt fiber, and Example 9 uses only lignin fiber. As shown in Table 1, the skid resistance value and noise reduction coefficient of Example 4 are superior to those of Examples 8 and 9, indicating that the composite fiber system is superior to the single fiber system. It is evident that basalt fiber mainly plays a role in strengthening the skeleton and improving structural stability, while lignin fiber is more conducive to adsorbing asphalt, inhibiting asphalt flow, and maintaining pore structure stability. The combination of the two can reduce the loosening and shedding of roughened elastic noise-reducing particles and aggregates during service, while maintaining a more stable road surface roughness structure and internal energy-absorbing structure, thus achieving better synergy between skid resistance and noise reduction.

[0048] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. An asphalt concrete that combines anti-skid and noise reduction properties, characterized in that: The raw materials of the asphalt concrete include the following components in parts by weight: 72-82 parts of high polishing value coarse aggregate, 10-18 parts of fine aggregate, 4-8 parts of composite filler, 2-6 parts of roughened elastic noise-reducing particles, 0.2-0.6 parts of fiber stabilizer, and 5.5-7.2 parts of modified asphalt.

2. The asphalt concrete with both anti-skid and noise-reducing properties according to claim 1, characterized in that: The preparation method of the roughened elastic noise reduction particles includes the following steps: Preheat the rubber granules to 70-90℃, spray with adhesive material, then stir at 80-110℃ for 3-8 minutes, add calcined bauxite powder, mix and coat at 80-100℃ for 5-10 minutes, cool, and obtain roughened elastic noise-reducing granules.

3. The asphalt concrete with both anti-skid and noise-reducing properties according to claim 2, characterized in that: The weight ratio of the rubber particles to the calcined bauxite powder is 85:(12-16), and the weight ratio of the binder to the rubber particles is (5-6):

100.

4. The asphalt concrete with both anti-skid and noise-reducing properties according to claim 2, characterized in that: The method for preparing the bonding material includes the following steps: Heat the base asphalt to 145-155℃ and hold for 20-30 minutes to fully melt it and make it fluid. Add aromatic oil under stirring and mix. Then raise the temperature to 165-175℃ and slowly add SBS under stirring. After adding, shear disperse the SBS. Then maintain the system at 175-185℃ and continue stirring for 40-90 minutes to obtain system A. Add the tackifying resin to system A at 170-180℃ and continue stirring for 20-40 minutes. Then adjust the temperature to 165-175℃, add the stabilizer and antioxidant in sequence, stir for 10-20 minutes, and finally cure at 165-175℃ for 20-40 minutes. Filter the material to obtain the adhesive material.

5. An asphalt concrete with both anti-skid and noise-reducing properties according to claim 4, characterized in that: In the preparation steps of the bonding material, the weight ratio of the base asphalt, aromatic oil, SBS, tackifying resin, stabilizer, and antioxidant is 100:(2-4):(4-6):(1-3):(0.1-0.2):(0.1-0.3).

6. The asphalt concrete with both anti-skid and noise-reducing properties according to claim 1, characterized in that: The composite filler comprises a mixture of limestone powder, diatomaceous earth, and hydrated lime.

7. The asphalt concrete with both anti-skid and noise-reducing properties according to claim 1, characterized in that: The fiber stabilizer comprises a mixture of basalt fiber and lignin fiber.

8. The asphalt concrete with both anti-skid and noise-reducing properties according to claim 1, characterized in that: The high-polish coarse aggregate includes basalt; the fine aggregate includes limestone manufactured sand.

9. A method for preparing asphalt concrete with both skid resistance and noise reduction properties as described in any one of claims 1-8, characterized in that: Includes the following steps: High-polish coarse aggregate and fine aggregate are heated to 170-185℃ and stirred to obtain mixture A. After the composite filler is dried, it is added to mixture A and stirred. Then, fiber stabilizer is added and stirred to obtain mixture B. Add some modified asphalt to mixture B and wet mix for 25-40 seconds. Then add roughened elastic noise-reducing particles and the remaining modified asphalt in sequence, and continue mixing for 20-35 seconds. Discharge the material at 170-175℃ to obtain asphalt concrete.

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