An asphalt mixture for airport pavement and its preparation method

Abstract

This application relates to the field of airport pavement construction materials, and specifically discloses an asphalt mixture for airport pavement and a preparation method thereof. The asphalt mixture comprises the following raw materials: modified asphalt, coarse aggregate, fine aggregate, mineral powder, fiber stabilizer, and rutting resistance agent. Among them, the modified asphalt is a mixture of SBS modified asphalt and rubber-PS-PPO modified asphalt; the rubber-PS-PPO modified asphalt is mainly prepared from a mixture of PS, PPO, polyethylene terephthalate, N-benzoylaniline cross-linked modified matrix asphalt, and styrene-butadiene rubber. The preparation method comprises the following steps: heating the coarse aggregate and the fine aggregate, adding the fiber stabilizer, and mixing to obtain a first mixture; heating the modified asphalt, adding the rutting resistance agent, and mixing to obtain a second mixture, adding the second mixture to the first mixture, mixing, adding the mineral powder, and mixing to obtain the asphalt mixture. This application has the characteristic of further improving the high-temperature rutting resistance performance of the asphalt mixture.

Description

Technical Field

[0001] The present application relates to the field of airport pavement construction materials, and more specifically, to an asphalt mixture for airport pavement and a preparation method thereof. Background Art

[0002] Airport pavement is the most important component of airport infrastructure, mainly used for the takeoff, landing and taxiing of aircraft. At present, the structural forms of airport pavements in various countries mainly include asphalt concrete pavements and cement concrete pavements. Among them, asphalt pavements have the characteristics of smooth surface, no joints, comfortable wear resistance, small vibration, low noise and short construction period, and occupy a dominant position in the structural forms of international airport pavements.

[0003] The mass and moment of inertia of an aircraft are very large, far exceeding that of an automobile. The aircraft load is a vibration-moving load, and this load form is likely to cause vertical deformation of the airport pavement. At the same time, the erosion of the high-temperature exhaust gas ejected by the aircraft on the asphalt mixture accelerates the aging of the pavement material. Under the conditions of high temperature and repeated loading of large loads, the rutting disease of the airport pavement has become one of the most easily occurring and most influential structural damage forms in airport asphalt pavements. Therefore, it is required that the airport pavement has higher high-temperature rutting resistance than highway pavements. Summary of the Invention

[0004] In order to further improve the high-temperature rutting resistance of the asphalt mixture, the present application provides an asphalt mixture for airport pavement and a preparation method thereof.

[0005] In the first aspect, the present application provides an asphalt mixture for airport pavement, adopting the following technical solution:

[0006] An asphalt mixture for airport pavement, comprising the following raw materials in parts by weight: 80-100 parts of modified asphalt, 800-950 parts of coarse aggregate, 250-350 parts of fine aggregate, 80-120 parts of mineral powder, 8-15 parts of fiber stabilizer, 1-3 parts of rutting inhibitor;

[0007] Among them, the modified asphalt is a mixture obtained by mixing SBS modified asphalt and rubber-PS-PPO modified asphalt in a mass ratio of 1:(3-5);

[0008] The rubber-PS-PPO modified asphalt is mainly prepared from PS, PPO, polyethylene terephthalate, and a mixture of N-benzoylaniline cross-linked modified matrix asphalt and styrene-butadiene rubber.

[0009] By adopting the above technical solution, the modified asphalt in this application selects a mixture of SBS modified asphalt and rubber-PS-PPO modified asphalt. The rubber-PS-PPO modified asphalt is prepared from a mixture of PS, PPO, polyethylene terephthalate, N-benzoylaniline modified matrix asphalt and styrene-butadiene rubber. The introduction of styrene-butadiene rubber can increase the modulus of the asphalt mixture, effectively reduce the deformation of the airport pavement under the action of wheel loads, improve its resistance to high-temperature deformation, thereby reducing pavement rutting. Moreover, styrene-butadiene rubber contains double bonds and benzene ring groups, and the introduction of benzene ring groups further improves its rigidity and high-temperature resistance. Polyphenylene oxide PPO has the characteristic of high modulus. Coupled with the blending modification of polystyrene PS, its stress cracking resistance and impact resistance are improved. Modifying the matrix asphalt with it can improve the impact resistance of the asphalt mixture, thereby improving its high-temperature rutting resistance.

[0010] The addition of polyethylene terephthalate and N-benzoylaniline introduces benzene ring rigid groups, which are used to modify the matrix asphalt and styrene-butadiene rubber, significantly improving the high-temperature deformation resistance of the asphalt mixture, thereby enhancing its high-temperature rutting resistance. In addition, styrene-butadiene rubber has double bond groups, and its double bond groups react with N-benzoylaniline, polyethylene terephthalate, polystyrene PS, etc. through cross-linking copolymerization and other modification effects, so that the modified asphalt obtained by modifying the matrix asphalt and styrene-butadiene rubber mixture with PS, PPO and polyethylene terephthalate has better high-temperature rutting resistance.

[0011] Optionally, the rubber-PS-PPO modified asphalt is prepared from the following raw materials in parts by weight: 20-30 parts of matrix asphalt, 8-12 parts of styrene-butadiene rubber, 3-5 parts of PS, 3-5 parts of PPO, 4-6 parts of polyethylene terephthalate, 5-10 parts of N-benzoylaniline, 1-3 parts of glutaraldehyde and 1-3 parts of initiator.

[0012] Optionally, the rubber-PS-PPO modified asphalt is prepared by the following method:

[0013] Heat the matrix asphalt to 180-200 °C, then add styrene-butadiene rubber, stir and mix, then add the initiator, mix and stir to obtain mixture A;

[0014] Mix PS and PPO and then add them to mixture A, mix and stir, then add polyethylene terephthalate and N-benzoylaniline, mix and stir, then add glutaraldehyde, react for 40-60 min and then cool to obtain rubber-PS-PPO modified asphalt.

[0015] By adopting the above technical solution, the matrix asphalt is first mixed with styrene-butadiene rubber and then other modifiers are added, so as to realize the modification effects such as cross-linking copolymerization among the above raw materials, form a macromolecular network structure, and improve the high-temperature rutting resistance of the asphalt mixture.

[0016] Optionally, the fiber stabilizer is a mixture of polyacrylonitrile and glass fiber with a mass ratio of 1:(2 - 3).

[0017] By adopting the above technical solution, the addition of the fiber stabilizer can further improve its high-temperature resistance. The addition of polyacrylonitrile fiber and glass fiber can not only improve the high-temperature performance of the asphalt mixture, but also play a certain role in reinforcement, improve the strength of the asphalt mixture, and improve its rutting resistance.

[0018] Optionally, the glass fiber is added after being modified by nano-silica-carbon nanotube deposition. The specific operation is as follows:

[0019] Mix nano-silica, multi-walled carbon nanotubes and silane coupling agent, and dry to obtain a preliminary mixture;

[0020] Perform amination modification on the glass fiber to obtain aminated modified glass fiber;

[0021] Mix the preliminary mixture, aminated modified glass fiber and polyvinyl alcohol solution, stir and dry to obtain modified glass fiber.

[0022] By adopting the above technical solution, nano-silica particles are grafted on the surface of multi-walled carbon nanotubes by using silane coupling agent, and then the preliminary mixture of silica-multi-walled carbon nanotubes is deposited on the glass fiber through polyvinyl alcohol solution, so that the glass fiber forms a root-hair structure, has better interfacial adhesion with the raw materials of the asphalt mixture in this application, improves its modulus, further improves its high-temperature rutting resistance, and the glass fiber matrix is aminated modified glass fiber, which forms a chemical interaction with nano-silica particles, and the deposition is more stable, further improving its high-temperature rutting resistance.

[0023] Optionally, the specific operation of the amination modification of the glass fiber is as follows:

[0024] First, treat the glass fiber in hydrochloric acid solution for 6 - 8 h at a treatment temperature of 90 - 100 °C, then wash with water and add water, then add γ-aminopropyltrimethoxysilane, stir, perform oil bath at 110 °C - 120 °C for 4 - 5 h, then wash with water, wash with ethanol, filter and dry to obtain aminated modified glass fiber.

[0025] By adopting the above technical solution, the glass fiber is first treated with hydrochloric acid to realize the hydroxylation of the glass fiber, improve the surface hydroxyl content, and then realize the amination modification of the glass fiber under the action of γ-aminopropyltrimethoxysilane.

[0026] Optionally, when the glass fiber is modified by nano-silica-carbon nanotube deposition,

[0027] the mass ratio of the added nano-silica, multi-walled carbon nanotubes and silane coupling agent is 1:(0.4 - 0.6):(0.2 - 0.5);

[0028] the mass ratio of the added initial mixture, amine-modified glass fiber and polyvinyl alcohol is 1:(2 - 3):(0.5 - 0.8); the polyvinyl alcohol solution is obtained by mixing polyvinyl alcohol with 6 - 8 mass times of water.

[0029] Optionally, in the step of amine-modifying the glass fiber, the mass ratio of the added glass fiber to γ-aminopropyltrimethoxysilane is 1:(0.2 - 0.5).

[0030] Optionally, the coarse aggregate is selected as the first crushed stone and the second crushed stone with a mass ratio of 1:(0.8 - 0.9), the particle size of the first crushed stone is 5 - 10 mm, and the particle size of the second crushed stone is 10 - 20 mm;

[0031] the fine aggregate is selected as sand with a particle size of 0 - 5 mm.

[0032] In the second aspect, the present application provides a preparation method of an asphalt mixture for airport pavement, adopting the following technical solution:

[0033] A preparation method of an asphalt mixture for airport pavement includes the following steps:

[0034] Heat the coarse aggregate and the fine aggregate at 190 - 205 °C, then add the fiber stabilizer and mix dry to obtain the first mixture;

[0035] Heat the modified asphalt to 170 - 185 °C, then add the rutting resistance agent and mix to obtain the second mixture, add the second mixture to the first mixture, mix, and then add the mineral powder and mix to obtain the asphalt mixture.

[0036] By adopting the above technical solution, the preparation method in the present application is simple and convenient, and is easy to realize industrialization.

[0037] In summary, the present application has the following beneficial effects:

[0038] 1. The rubber-PS-PPO modified asphalt is added in this application. The introduction of styrene-butadiene rubber can increase the modulus of the asphalt mixture, effectively reduce the deformation of the airport pavement under the action of wheel loads, improve its resistance to high-temperature deformation, thereby reducing pavement rutting. Moreover, the styrene-butadiene rubber contains double bonds and benzene ring groups, and the introduction of benzene ring groups further improves its rigidity and high-temperature resistance. Polyphenylene oxide PPO has the characteristic of high modulus. Coupled with the blending modification of polystyrene PS, its stress cracking resistance and impact resistance are improved. Modifying the base asphalt with it can improve the impact resistance of the asphalt mixture, thereby improving its high-temperature rutting resistance;

[0039] 2. When rubber-PS-PPO modified asphalt is used in this application, polyethylene terephthalate and N-benzoylaniline are added to introduce benzene ring rigid groups, and they are used to modify the base asphalt and styrene-butadiene rubber, significantly improving the high-temperature deformation resistance of the asphalt mixture, thereby improving its high-temperature rutting resistance. In addition, the styrene-butadiene rubber has double bond groups, and its double bond groups and N-benzoylaniline, polyethylene terephthalate, polystyrene PS, etc. have cross-linking copolymerization and other modification effects with each other. Therefore, the modified asphalt obtained by modifying the mixture of base asphalt and styrene-butadiene rubber with PS, PPO, and polyethylene terephthalate has better high-temperature rutting resistance;

[0040] 3. Modified glass fiber is added to the fiber stabilizer in this application. Silane coupling agent is used to graft nano-silica particles on the surface of multi-walled carbon nanotubes, and then the silica-multi-walled carbon nanotube premix is deposited on the glass fiber through polyvinyl alcohol solution, making the glass fiber form a root-hair structure, which has better interfacial adhesion with the raw materials of the asphalt mixture in this application, increases its modulus, and further improves its high-temperature rutting resistance. Moreover, the glass fiber matrix is aminated modified glass fiber, and a chemical interaction is formed between it and nano-silica particles, and the deposition is more stable, further improving its high-temperature rutting resistance. Detailed implementation mode

[0041] The following further details this application with reference to embodiments. It should be specifically noted that: for those not specifying specific conditions in the following embodiments, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. Except for special instructions, the raw materials used in the following embodiments can all be obtained from ordinary commercial sources.

[0042] In the following embodiments, the performance indicators of SBS modified asphalt are shown in Table 1 below:

[0043]

[0044]

[0045] The grade of the base asphalt is 90# A-grade;

[0046] The fine aggregate is manufactured sand with a particle size of 0 - 5 mm;

[0047] The mineral powder is S95 - grade mineral powder;

[0048] The rutting resistance agent selected is the special rutting resistance agent AM - 500 for airport pavement developed by Haichuan New Materials.

[0049] The following preparation examples are for the preparation of rubber - PS - PPO modified asphalt

[0050] Preparation Example 1

[0051] A preparation method of rubber - PS - PPO modified asphalt, comprising the following steps:

[0052] Heat 25 kg of base asphalt to 190 °C, then add 10 kg of styrene - butadiene rubber, stir and mix, then add 2 kg of initiator azobisisobutyronitrile, mix and stir to obtain mixture A;

[0053] Mix 4 kg of polystyrene (PS) and 4 kg of polyphenylene oxide (PPO), then add them to mixture A, mix and stir, then add 5 kg of polyethylene terephthalate, 8 kg of N - benzoylaniline, after mixing and stirring, add 2 kg of glutaraldehyde, react for 50 min and then cool to obtain rubber - PS - PPO modified asphalt.

[0054] Preparation Example 2

[0055] A preparation method of rubber - PS - PPO modified asphalt, comprising the following steps:

[0056] Heat 20 kg of base asphalt to 180 °C, then add 8 kg of styrene - butadiene rubber, stir and mix, then add 1 kg of initiator azobisisobutyronitrile, mix and stir to obtain mixture A;

[0057] Mix 3 kg of polystyrene (PS) and 3 kg of polyphenylene oxide (PPO), then add them to mixture A, mix and stir, then add 4 kg of polyethylene terephthalate, 5 kg of N - benzoylaniline, after mixing and stirring, add 1 kg of glutaraldehyde, react for 40 min and then cool to obtain rubber - PS - PPO modified asphalt.

[0058] Preparation Example 3

[0059] A preparation method of rubber - PS - PPO modified asphalt, comprising the following steps:

[0060] Heat 30 kg of base asphalt to 200 °C, then add 12 kg of styrene - butadiene rubber, stir and mix, then add 3 kg of initiator azobisisobutyronitrile, mix and stir to obtain mixture A;

[0061] Mix 5 kg of polystyrene (PS) and 5 kg of polyphenylene oxide (PPO), then add the mixture to mixture A, mix and stir. Next, add 6 kg of polyethylene terephthalate and 10 kg of N-benzoylaniline. After mixing and stirring, add 3 kg of glutaraldehyde. After reacting for 60 min, cool to obtain rubber-PS-PPO modified asphalt.

[0062] Comparative Preparation Example 1

[0063] A method for preparing rubber-PS-PPO modified asphalt is carried out according to the method in Preparation Example 1, except that polyethylene terephthalate is not added to the raw materials.

[0064] Comparative Preparation Example 2

[0065] A method for preparing rubber-PS-PPO modified asphalt is carried out according to the method in Preparation Example 1, except that N-benzoylaniline is not added to the raw materials.

[0066] Comparative Preparation Example 3

[0067] A method for preparing rubber-PS-PPO modified asphalt is carried out according to the method in Preparation Example 1, except that styrene-butadiene rubber in the raw materials is replaced with cis-1,4-polybutadiene rubber in equal amount.

[0068] The following Preparation Examples 4-6 are preparation examples of modified glass fibers

[0069] Preparation Example 4

[0070] A method for preparing modified glass fibers includes the following steps:

[0071] Mix nano-silica, multi-walled carbon nanotubes and silane coupling agent KH-570 according to the mass ratio of 1:0.5:0.3, and dry to obtain a preliminary mixture;

[0072] First, soak the glass fibers in a 20 wt% hydrochloric acid solution for 7 h at a treatment temperature of 95 °C, then wash with water and add water. The added amount of water is 9 times the mass of the glass fibers. Then add γ-aminopropyltrimethoxysilane. The added mass ratio of the glass fibers to γ-aminopropyltrimethoxysilane is 1:0.3. Stir and carry out an oil bath at 115 °C for 4.5 h. Then wash with water, wash with ethanol, filter, and dry to obtain aminated modified glass fibers;

[0073] Mix the preliminary mixture, aminated modified glass fibers and polyvinyl alcohol solution, stir and dry to prepare modified glass fibers; the polyvinyl alcohol solution is obtained by dissolving polyvinyl alcohol in 6-8 times the mass of water, and the added mass ratio of the preliminary mixture, aminated modified glass fibers and polyvinyl alcohol is 1:2.5:0.6.

[0074] Preparation Example 5

[0075] A preparation method of modified glass fiber, comprising the following steps:

[0076] Mix nano-silica, multi-walled carbon nanotubes and silane coupling agent KH-570 according to a mass ratio of 1:0.4:0.2, and dry to obtain a preliminary mixture;

[0077] First soak the glass fiber in a 20wt% hydrochloric acid solution for 6h at a treatment temperature of 90°C, then wash with water and add water. The added amount of water is 8 times the mass of the glass fiber. Then add γ-aminopropyltrimethoxysilane. The added mass ratio of the glass fiber to γ-aminopropyltrimethoxysilane is 1:0.2. Stir and carry out an oil bath at 110°C for 5h, then wash with water, wash with ethanol, filter and dry to obtain aminated modified glass fiber;

[0078] Mix the preliminary mixture, aminated modified glass fiber and polyvinyl alcohol solution, stir and dry to obtain modified glass fiber; wherein the polyvinyl alcohol solution is obtained by dissolving polyvinyl alcohol in 6 times the mass of water, and the added mass ratio of the preliminary mixture, aminated modified glass fiber and polyvinyl alcohol is 1:2:0.5.

[0079] Preparation Example 6

[0080] A preparation method of modified glass fiber, comprising the following steps:

[0081] Mix nano-silica, multi-walled carbon nanotubes and silane coupling agent KH-570 according to a mass ratio of 1:0.6:0.5, and dry to obtain a preliminary mixture;

[0082] First soak the glass fiber in a 20wt% hydrochloric acid solution for 8h at a treatment temperature of 100°C, then wash with water and add water. The added amount of water is 10 times the mass of the glass fiber. Then add γ-aminopropyltrimethoxysilane. The added mass ratio of the glass fiber to γ-aminopropyltrimethoxysilane is 1:0.5. Stir and carry out an oil bath at 120°C for 4h, then wash with water, wash with ethanol, filter and dry to obtain aminated modified glass fiber;

[0083] Mix the preliminary mixture, aminated modified glass fiber and polyvinyl alcohol solution, stir and dry to obtain modified glass fiber; wherein the polyvinyl alcohol solution is obtained by dissolving polyvinyl alcohol in 8 times the mass of water, and the added mass ratio of the preliminary mixture, aminated modified glass fiber and polyvinyl alcohol is 1:3:0.8.

[0084] Preparation Example 7

[0085] A preparation method of modified glass fiber is carried out according to the method in Preparation Example 4, the difference is that the glass fiber is not treated by hydrochloric acid soaking, and γ-aminopropyltrimethoxysilane is directly added for treatment.

[0086] Comparative Preparation Example 4

[0087] A method for preparing modified glass fiber is carried out according to the method in Preparation Example 4, except that the glass fiber is not subjected to amination modification treatment, and the premix, glass fiber and polyvinyl alcohol solution are directly mixed.

[0088] Example 1

[0089] A method for preparing an asphalt mixture for airport pavement includes the following steps:

[0090] Mix 900 kg of coarse aggregate and 300 kg of fine aggregate, heat them at 200 °C, then add 12 kg of fiber stabilizer and mix dry to obtain a first mixture;

[0091] Among them, the coarse aggregate is the first crushed stone and the second crushed stone with a mass ratio of 1:0.8. The particle size of the first crushed stone is 5-10 mm, and the particle size of the second crushed stone is 10-20 mm; the fine aggregate is manufactured sand with a particle size of 0-5 mm; the fiber stabilizer is a mixture of polyacrylonitrile and glass fiber with a mass ratio of 1:2.5;

[0092] Heat 90 kg of modified asphalt to 180 °C, then add 2 kg of rutting resistance agent and mix to obtain a second mixture. Add the second mixture to the first mixture, mix, and then add 100 kg of mineral powder and mix to obtain the asphalt mixture;

[0093] Among them, the modified asphalt is a mixture obtained by mixing SBS modified asphalt and the rubber-PS-PPO modified asphalt prepared in Preparation Example 1 according to a mass ratio of 1:4.

[0094] Example 2

[0095] A method for preparing an asphalt mixture for airport pavement includes the following steps:

[0096] Mix 800 kg of coarse aggregate and 250 kg of fine aggregate, heat them at 190 °C, then add 8 kg of fiber stabilizer and mix dry to obtain a first mixture;

[0097] Among them, the coarse aggregate is the first crushed stone and the second crushed stone with a mass ratio of 1:0.8. The particle size of the first crushed stone is 5-10 mm, and the particle size of the second crushed stone is 10-20 mm; the fine aggregate is manufactured sand with a particle size of 0-5 mm; the fiber stabilizer is a mixture of polyacrylonitrile and glass fiber with a mass ratio of 1:2;

[0098] Heat 80 kg of modified asphalt to 170 °C, then add 1 kg of rutting resistance agent and mix to obtain a second mixture. Add the second mixture to the first mixture, mix, and then add 80 kg of mineral powder and mix to obtain the asphalt mixture;

[0099] Among them, the modified asphalt is a mixture obtained by mixing SBS modified asphalt and the rubber-PS-PPO modified asphalt prepared in Preparation Example 2 in a mass ratio of 1:3.

[0100] Example 3

[0101] A preparation method of an asphalt mixture for airport pavement includes the following steps:

[0102] Mix 950 kg of coarse aggregate and 350 kg of fine aggregate, heat them at 205 °C, then add 15 kg of fiber stabilizer and mix dry to obtain a first mixture;

[0103] Among them, the coarse aggregate is the first crushed stone and the second crushed stone with a mass ratio of 1:0.9. The particle size of the first crushed stone is 5-10 mm, and the particle size of the second crushed stone is 10-20 mm; the fine aggregate is manufactured sand with a particle size of 0-5 mm; the fiber stabilizer is a mixture of polyacrylonitrile and glass fiber with a mass ratio of 1:3;

[0104] Heat 100 kg of modified asphalt to 185 °C, then add 3 kg of rutting resistance agent and mix to obtain a second mixture. Add the second mixture to the first mixture, mix, and then add 120 kg of mineral powder and mix to obtain the asphalt mixture;

[0105] Among them, the modified asphalt is a mixture obtained by mixing SBS modified asphalt and the rubber-PS-PPO modified asphalt prepared in Preparation Example 3 in a mass ratio of 1:5.

[0106] Examples 4-7

[0107] A preparation method of an asphalt mixture for airport pavement is carried out according to the method in Example 1, except that the fiber stabilizer is respectively the modified glass fiber prepared in Preparation Examples 4-7.

[0108] Example 8

[0109] A preparation method of an asphalt mixture for airport pavement is carried out according to the method in Example 1, except that the fiber stabilizer is the modified glass fiber prepared in Comparative Preparation Example 4.

[0110] Comparative Example 1

[0111] A preparation method of an asphalt mixture for airport pavement is carried out according to the method in Example 1, except that the modified asphalt is SBS modified asphalt.

[0112] Comparative Examples 2-4

[0113] A preparation method of asphalt mixture for airport pavement is carried out according to the method in Example 1, with the difference that the rubber-PS-PPO modified asphalt is selected from the rubber-PS-PPO modified asphalt prepared in Comparative Preparation Examples 1-3.

[0114] Performance detection

[0115] The asphalt mixtures prepared in the examples and comparative examples of this application were subjected to rutting tests according to the Test Regulations for Asphalt and Asphalt Mixtures in Highway Engineering (JTJ052-2000) under the conditions of 60±1°C and 0.7±0.05 MPa. The test results are shown in Table 1 below:

[0116] Table 1:

[0117]

[0118] Combined with the detection results in Table 1 above, it can be seen that the asphalt mixture prepared in the examples of this application has excellent high-temperature rutting resistance. Combining the detection results of Example 1 and Examples 4-6, when glass fiber is added after being modified, its high-temperature rutting resistance is further significantly improved. Combining with the detection result of Example 7, during the modification process of glass fiber, without undergoing hydrochloric acid hydroxylation treatment and directly undergoing amination treatment and then bonding with nano-silica-multi-walled carbon nanotubes, its high-temperature rutting resistance is improved compared to Example 1, but weaker than the detection result of Example 4. Referring to the detection results of Example 1 and Example 8 again, when glass fiber is not aminated and directly bonded with nano-silica-multi-walled carbon nanotubes, its performance decreases. When glass fiber is hydroxylated and then aminated and then bonded with nano-silica-multi-walled carbon nanotubes, its high-temperature rutting resistance is better.

[0119] Referring to the detection results of Example 1 and Comparative Example 1 again, when all the modified asphalt is selected as SBS modified asphalt, its performance is weak. When the modified asphalt is a mixture of SBS modified asphalt and rubber-PS-PPO modified asphalt, its high-temperature rutting resistance is better. Combining with the detection results of Comparative Examples 2-4, when polyethylene terephthalate or N-benzoylaniline is not added during the preparation of rubber-PS-PPO modified asphalt, its high-temperature rutting resistance decreases, and when styrene-butadiene rubber is replaced with cis-butadiene rubber, its high-temperature rutting resistance also decreases. During the modification of the above substances, grafting, cross-linking and other reactions form macromolecular substances, significantly improving the high-temperature rutting resistance.

[0120] This specific embodiment is only an explanation of this application and is not a limitation of this application. Those skilled in the art can make modifications without creative contributions to this embodiment according to their needs after reading this specification, but as long as they are within the scope of the claims of this application, they are protected by the patent law.

Claims

1. An asphalt mixture for airport pavement, characterized in that, It includes the following raw materials in parts by weight: 80 - 100 parts of modified asphalt, 800 - 950 parts of coarse aggregate, 250 - 350 parts of fine aggregate, 80 - 120 parts of mineral powder, 8 - 15 parts of fiber stabilizer, 1 - 3 parts of rutting resistance agent; Among them, the modified asphalt is a mixture obtained by mixing SBS modified asphalt and rubber - PS - PPO modified asphalt in a mass ratio of 1:(3 - 5); The rubber - PS - PPO modified asphalt is mainly prepared from a mixture of PS, PPO, polyethylene terephthalate, N - benzoylaniline cross - linked modified matrix asphalt and styrene - butadiene rubber; The rubber - PS - PPO modified asphalt is prepared by the following method: Heat the matrix asphalt to 180 - 200 °C, then add styrene - butadiene rubber, stir and mix, then add an initiator, and mix and stir to obtain mixture A; Mix PS and PPO and then add them to mixture A, mix and stir, then add polyethylene terephthalate and N - benzoylaniline, mix and stir, and then add glutaraldehyde. After reacting for 40 - 60 min, cool to obtain rubber - PS - PPO modified asphalt.

2. The asphalt mixture for airport pavement according to claim 1, wherein: The rubber - PS - PPO modified asphalt is prepared from the following raw materials in parts by weight: 20 - 30 parts of matrix asphalt, 8 - 12 parts of styrene - butadiene rubber, 3 - 5 parts of PS, 3 - 5 parts of PPO, 4 - 6 parts of polyethylene terephthalate, 5 - 10 parts of N - benzoylaniline, 1 - 3 parts of glutaraldehyde and 1 - 3 parts of initiator.

3. The asphalt mixture for airport pavement according to claim 1, wherein: The fiber stabilizer is a mixture of polyacrylonitrile and glass fiber with a mass ratio of 1:(2 - 3).

4. The asphalt mixture for airport pavement according to claim 3, wherein: The glass fiber is added after being modified by nano - silica - carbon nanotube deposition. The specific operation is as follows: Mix nano - silica, multi - walled carbon nanotubes and silane coupling agent, and dry to obtain a preliminary mixture; Carry out amination modification on the glass fiber to obtain aminated modified glass fiber; Mix the preliminary mixture, aminated modified glass fiber and polyvinyl alcohol solution, stir and dry to obtain modified glass fiber.

5. An asphalt mixture for airport pavement according to claim 4, characterized in that: The specific operation of the amination modification of the glass fiber is as follows: First, treat the glass fiber in a hydrochloric acid solution for 6 - 8 h at a treatment temperature of 90 - 100 °C, then wash with water and add water, then add γ - aminopropyltrimethoxysilane, stir, carry out oil bath at 110 °C - 120 °C for 4 - 5 h, then wash with water, wash with ethanol, filter and dry to obtain aminated modified glass fiber.

6. The asphalt mixture for airport pavement according to claim 4, wherein: When the glass fiber is modified by nano - silica - carbon nanotube deposition, The mass ratio of the addition of nano - silica, multi - walled carbon nanotubes and silane coupling agent is 1:(0.4 - 0.6):(0.2 - 0.5); The mass ratio of the addition of the preliminary mixture, aminated modified glass fiber and polyvinyl alcohol is 1:(2 - 3):(0.5 - 0.8); The polyvinyl alcohol solution is obtained by dissolving polyvinyl alcohol in 6 - 8 mass times of water and mixing.

7. An asphalt mixture for airport pavement according to claim 5, characterized in that: In the step of amination modification of the glass fiber, the mass ratio of the addition of the glass fiber to γ - aminopropyltrimethoxysilane is 1:(0.2 - 0.5).

8. An asphalt mixture for airport pavement according to claim 1, characterized in that: The coarse aggregate is selected as the first crushed stone and the second crushed stone with a mass ratio of 1:(0.8 - 0.9). The particle size of the first crushed stone is 5 - 10 mm, and the particle size of the second crushed stone is 10 - 20 mm; The fine aggregate is selected as sand with a particle size of 0 - 5 mm.

9. The preparation method of an asphalt mixture for airport pavement according to any one of claims 1-8, characterized in that: It includes the following steps: Heat the coarse aggregate and the fine aggregate at 190 - 205 °C, then add a fiber stabilizer and mix dry to obtain a first mixture; Heat the modified asphalt to 170 - 185 °C, then add an anti-rutting agent and mix to obtain a second mixture. Add the second mixture to the first mixture, mix, then add mineral powder and mix to obtain an asphalt mixture.

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