Water-activated cold patch asphalt, water-activated cold patch asphalt mixture and preparation method thereof

Abstract

The present application discloses a water-activated cold patch asphalt, a water-activated cold patch asphalt mixture and a preparation method thereof. 100 parts of base asphalt, 20-30 parts of bio-oil diluent, 30-45 parts of polyurethane prepolymer, and 1-5 parts of water remover; the polyurethane prepolymer includes a main polyurethane prepolymer and an organosilicon-modified polyurethane prepolymer, and the organosilicon-modified polyurethane prepolymer accounts for 20-30wt%. The organosilicon-modified polyurethane prepolymer is prepared by a polyurethane prepolymer containing a carbon-carbon double bond and a siloxane compound containing a silicon hydrogen group in a mass ratio of 15-25:1 through a silylation reaction. The cold patch asphalt mixture of the present application has excellent water damage resistance and has strong adaptability to harsh environments such as rain, snow and water accumulation.

Description

Technical Field

[0001] The present application relates to the field of asphalt, and in particular to a water-activated cold-patch asphalt, a water-activated cold-patch asphalt mixture and a preparation method thereof. Background Art

[0002] In road repair operations, traditional asphalt warm patching technology is subject to the characteristics of asphalt itself, and there are many inconveniences and limitations. Specifically, conventional asphalt is solid or semi-solid at room temperature, with high viscosity and poor fluidity. In order to ensure good operability during repair construction, it is necessary to use heating means to increase its temperature, soften the asphalt, and enhance its fluidity, so that it can be evenly spread and compacted, and closely integrated with the existing structure of the road surface. This heating process requires special heating equipment, such as large heating kettles and hot spray guns, which not only consume a lot of energy and have cumbersome operating procedures, but are also easily restricted by construction site conditions such as power supply and site space, greatly increasing the cost and difficulty of repair operations. In addition, in some scenarios where the use of open flames is restricted, heating operations are even more difficult to carry out.

[0003] With the development of technology, cold-patch asphalt has emerged, among which water-activated asphalt has attracted much attention. This type of cold-patch asphalt subverts the traditional heating mode. It gives asphalt good fluidity through diluents. It does not require additional heating treatment and can be used conveniently at room temperature, which greatly simplifies the repair process. Its unique formula design contains a curing agent component. When it comes into contact with water, the curing agent is activated and triggers a cross-linking and curing reaction in the asphalt system. Through this cross-linking process, a more stable and complex network structure is formed between asphalt molecules, effectively enhancing the overall strength of the asphalt system. Compared with the long strength formation cycle of conventional asphalt, water-activated cold-patch asphalt can reach considerable strength in a short time, greatly reducing the waiting time required for the repaired road surface to be opened to traffic, and significantly improving construction efficiency. In particular, with the characteristic of water activation, it can still smoothly achieve cross-linking reaction even in a low temperature environment, ensuring the effective implementation of the repair work, with excellent construction and workability, and can adapt to the road repair needs of different working conditions and different seasons. It can efficiently deal with common road diseases such as potholes and cracks, showing a wide range of applicability.

[0004] Although water-activated cold patch asphalt has significant advantages, its disadvantages are more obvious in complex and harsh natural environments, especially when facing long-term erosion by rain and snow. Existing cold patch asphalt materials have serious deficiencies in water damage resistance. When encountering rain erosion, snowmelt water immersion, etc., water molecules continue to penetrate into the internal structure of the asphalt mixture, destroying the formed cross-linking system, causing the adhesion between the asphalt and the aggregate to drop sharply, resulting in peeling. This peeling will not only weaken the structural integrity of the repaired part, but also lead to the recurrence of road diseases and frequent repairs, making it difficult to ensure the long-term stable operation of the road surface. Summary of the invention

[0005] In order to solve the shortcomings of water-activated cold patch asphalt in terms of water damage resistance, the present application provides a water-activated cold patch asphalt, a water-activated cold patch asphalt mixture and a preparation method thereof.

[0006] In a first aspect, the present application provides a water-activated cold patch asphalt, which includes the following raw materials in parts by weight:

[0007] 100 parts of base asphalt, 20-30 parts of bio-oil diluent, 30-45 parts of polyurethane prepolymer, 1-5 parts of water remover;

[0008] The polyurethane prepolymer comprises a main polyurethane prepolymer and an organosilicon-modified polyurethane prepolymer, and the organosilicon-modified polyurethane prepolymer accounts for 20 to 30 wt %.

[0009] In any of the above technical solutions, the isocyanate index of the main polyurethane prepolymer is 1.2 to 1.5.

[0010] In any of the above technical solutions, the matrix asphalt is selected from one or more of 50#, 70#, 90#, and 110# asphalt.

[0011] In any of the above technical solutions, the bio-oil diluent is a viscous or liquid substance rich in hydrocarbons obtained by high-pressure liquefaction, high-temperature thermal cracking or bio-enzymatic process of residues such as bioenergy, waste oils and industrial wastes. Optionally, the material source of the bio-oil diluent includes but is not limited to plant wastes such as straw, sawdust, and husks, or waste oils and fats.

[0012] In any of the above technical solutions, the dehydrating agent is vinyl trimethoxy silane, vinyl triethoxy silane or p-toluenesulfonyl isocyanate.

[0013] In any of the above technical solutions, the organosilicon-modified polyurethane prepolymer is prepared by a hydrosilylation reaction of a polyurethane prepolymer containing carbon-carbon double bonds and a siloxane compound containing silicon hydrogen groups in a mass ratio of 15 to 25:1.

[0014] In any of the above technical solutions, the polyurethane prepolymer or the main polyurethane prepolymer is obtained by reacting polyol and polyisocyanate at 40-100°C.

[0015] Exemplarily, the polyol is a polyester polyol or a polyether polyol.

[0016] Exemplarily, the polyisocyanate is selected from at least one of toluene diisocyanate, hexamethylene diisocyanate, hydrogenated diphenylmethane diisocyanate, diphenylmethane diisocyanate, and isophorone diisocyanate.

[0017] It should be noted that a catalyst, such as an organic tin catalyst, may be added during the reaction of the polyol and the polyisocyanate to accelerate the reaction rate. The isocyanate index of the present application is the molar ratio of the isocyanate group to the hydroxyl group in the reaction system; by controlling the amount of the polyisocyanate and the polyol, the polyurethane prepolymer with the isocyanate index of 1.2 to 1.5 can be obtained.

[0018] In any of the above technical solutions, the polyurethane prepolymer containing carbon-carbon double bonds is obtained by reacting a polyether polyol, a hydroxyl-containing acrylic compound and a polyisocyanate. In the reaction system, the molar ratio of the polyisocyanate group to the hydroxyl group is 1.1 to 1.3, and the molar ratio of the polyether polyol to the hydroxyl-containing acrylic compound is 1:2 to 3.

[0019] In addition, the hydrosilylation reaction is carried out in the presence of a platinum catalyst, with the amount of the platinum catalyst being 0.0001% to 0.001% of the total mass of the reaction raw materials.

[0020] In any of the above technical solutions, the hydroxyl-containing acrylic compound is selected from one or more of hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, and hydroxybutyl acrylate.

[0021] In any of the above technical solutions, the polyol is a polyester polyol or a polyether polyol.

[0022] Exemplarily, the polyether polyol is one or more of polyethylene oxide glycol, polypropylene oxide glycol, polytetramethylene glycol, and polypropylene oxide triol.

[0023] Exemplarily, the polyisocyanate is selected from at least one of toluene diisocyanate, hexamethylene diisocyanate, hydrogenated diphenylmethane diisocyanate, diphenylmethane diisocyanate, and isophorone diisocyanate.

[0024] It should be noted that the above-mentioned siloxane compound containing silicon hydrogen groups has hydrogen directly connected to the silicon atom, that is, Si—H, and the silicon atom is also connected to an alkoxy group, such as a methoxy group and an ethoxy group.

[0025] In any of the above technical solutions, the siloxane compound containing a silicon hydrogen group is selected from at least one of trimethoxysilane, triethoxysilane, methyldimethoxysilane and ethyldimethoxysilane.

[0026] This application uses polyurethane prepolymer as a curing agent. When it encounters water, the isocyanate groups it contains can trigger a cross-linking curing reaction, thereby quickly providing the asphalt system with initial curing strength. In order to enhance the water damage resistance of the asphalt system, this application uses a conventional main polyurethane prepolymer and a silicone-modified polyurethane prepolymer for matching, wherein the main polyurethane prepolymer is used to ensure the curing speed and quickly provide initial strength. The silicone segment of the silicone-modified polyurethane prepolymer can improve the hydrophobicity of the system and improve the water damage resistance.

[0027] Specifically, the organosilicon-modified polyurethane resin of the present application is first prepared by adding a monomer compound containing hydroxyl groups and propylene groups to the raw materials, which participates in the reaction to obtain a polyurethane prepolymer containing a carbon-carbon double bond (vinyl group), and then undergoes a silylation reaction with a siloxane compound containing a silicon hydrogen group to obtain an organosilicon-modified product having an organosilicon segment, thereby achieving hydrophobic modification.

[0028] It is worth noting that the siloxane compounds containing silicon hydrogen groups preferably used in this application all have multiple alkoxy groups ((RO) n S H 4-n , n≥2), alkoxy groups can be introduced into the organosilicon-modified polyurethane prepolymer, so that it can produce silanol groups after reacting with water. The silanol groups can form a stronger connection with inorganic substances such as aggregates and cement matrices of the road surface, effectively enhancing the curing strength (Marshall stability) of the cold patch asphalt system, while effectively enhancing the standing strength of the asphalt and the roadbed, and improving the shear strength, making it more tolerant to harsh environments such as water erosion and high pressure.

[0029] In a second aspect, the present application provides a water-activated cold patch asphalt mixture, which includes the following components in parts by weight:

[0030] 4-6 parts of any of the above-mentioned water-activated cold patch asphalt, 100 parts of aggregate, 1-2 parts of water-activated accelerator, and 0.5-1 part of calcium oxide.

[0031] In any of the above technical solutions, the water-activated accelerator is cement.

[0032] In any of the above technical solutions, the aggregate is selected from one or more of graded crushed stone, steel slag, tailings slag, coal gangue, road milling material, and recycled aggregate from construction waste.

[0033] In any of the above technical solutions, the gradation of the aggregate is a continuous gradation of AC-10, AC-13 or AC-16.

[0034] In any of the above technical solutions, the cement is ordinary Portland cement.

[0035] In a third aspect, the present application provides a method for preparing a water-activated cold patch asphalt mixture, comprising:

[0036] According to the proportion of any of the above-mentioned mixtures, aggregate, water-activated accelerator and water-activated cold patch asphalt are mixed, and stirred until the asphalt evenly coats the aggregate and no white material is obtained.

[0037] In any of the above technical solutions, in the pothole repair process, the amount of activated water used is 2 to 3% of the mass of the asphalt mixture.

[0038] When the asphalt mixture is activated by adding water, the hydration products of cement can cross-link and bond with the silanol groups obtained by hydrolysis of alkoxy groups in the organosilicon-modified polyurethane prepolymer, thereby forming an interpenetrating network structure with the polyurethane prepolymer, which helps to improve the Marshall stability of the asphalt system after curing. At the same time, it enhances the bonding strength between the asphalt mixture and the pavement matrix. Calcium oxide can react with water and carbon dioxide gas generated by the cross-linking and curing of polyurethane prepolymers to form calcium carbonate, which plays a certain role in strengthening the asphalt repair system. In addition, calcium oxide can play a certain role as a dehydrating agent to ensure the stability of the mixture.

[0039] In summary, this application has the following beneficial effects:

[0040] This application uses a main polyurethane prepolymer and a silicone-modified polyurethane prepolymer to improve its water damage resistance while ensuring the strength formation time of cold-patch asphalt. Furthermore, this application uses a polyurethane prepolymer containing a carbon-carbon double bond and a silicone compound with a silicon-hydrogen alkoxy group such as trimethoxysilane and triethoxysilane for silane hydrogen addition to obtain a silicone-modified polyurethane prepolymer with hydrophobicity and adhesion promotion, thereby improving the bonding strength between the cold-patch asphalt system and the pavement substrate.

[0041] In addition, the present application further enhances the strength of the cold patch asphalt system after curing and improves its Marshall stability by adding cement and calcium oxide to the asphalt mixture. DETAILED DESCRIPTION

[0042] Preparation Example: Preparation Example 1, a silicone-modified polyurethane prepolymer is prepared according to the following steps:

[0043] S1. Toluene diisocyanate, polyether triol and hydroxyethyl methacrylate in a molar ratio of 1.2:0.3:1.1 are used as reaction raw materials, and dibutyltin dilaurate of 0.0005% of the total mass of the above reaction raw materials is used as a catalyst. First, the polyether triol is dehydrated at 110°C and -0.1MPa for 2 hours, cooled to 70°C, added to the reaction container, stirred and toluene diisocyanate is added under nitrogen protection, reacted for 1 hour, and then dibutyltin dilaurate catalyst is added to continue the reaction for 2 hours, and finally hydroxyethyl methacrylate is added, and the reaction is continued for 3 hours to obtain a polyurethane prepolymer containing carbon-carbon double bonds.

[0044] S2. Take 200 g of a polyurethane prepolymer containing a carbon-carbon double bond and 10 g of trimethoxysilane, stir and mix them evenly, then add 20 ppm of a platinum catalyst coordinated with divinyltetramethylsiloxane (0.5% platinum content), heat to 80°C, react for 6 hours, cool after the reaction is completed, and vacuum to remove unreacted trimethoxysilane to obtain a silicone-modified polyurethane prepolymer.

[0045] Preparation Example 2: A silicone-modified polyurethane prepolymer is prepared according to the following steps:

[0046] S1. Isophorone diisocyanate, polyether triol and hydroxyethyl acrylate in a molar ratio of 1.1:0.4:0.8 are used as reaction raw materials, and dibutyltin dilaurate of 0.0006% of the total mass of the above reaction raw materials is used as a catalyst. First, the polyether triol is dehydrated at 110°C and -0.1MPa for 2h, cooled to 70°C, added to the reaction vessel, stirred and isophorone diisocyanate is added under nitrogen protection, reacted for 2h, dibutyltin dilaurate catalyst is added to continue the reaction for 2h, and finally hydroxyethyl acrylate is added and the reaction is continued for 2h to obtain a polyurethane prepolymer containing carbon-carbon double bonds.

[0047] S2. Take 180g of a polyurethane prepolymer containing a carbon-carbon double bond and 10g of methyldimethoxysilane, stir and mix, then add 20ppm of a platinum catalyst coordinated with divinyltetramethylsiloxane (0.5% platinum content), heat to 80°C, react for 6h, cool after the reaction, and vacuum to remove unreacted methyldimethoxysilane to obtain a silicone-modified polyurethane prepolymer.

[0048] Preparation Example 3, a silicone-modified polyurethane prepolymer is prepared according to the following steps:

[0049] S1. Toluene diisocyanate, polyether diol and hydroxyethyl methacrylate in a molar ratio of 1.2:0.5:1.0 are used as reaction raw materials, and dibutyltin dilaurate of 0.0005% of the total mass of the above reaction raw materials is used as a catalyst. First, the polyether diol is dehydrated at 100°C and -0.1MPa for 2 hours, cooled to 70°C, added to a reaction container, stirred and toluene diisocyanate is added under nitrogen protection, reacted for 1 hour, and then dibutyltin dilaurate catalyst is added to continue the reaction for 2 hours, and finally hydroxyethyl methacrylate is added, and the reaction is continued for 3 hours to obtain a polyurethane prepolymer containing carbon-carbon double bonds.

[0050] S2. Take 230g of a polyurethane prepolymer containing a carbon-carbon double bond and 10g of trimethoxysilane, stir and mix, then add 30ppm of a platinum catalyst coordinated with divinyltetramethylsiloxane (0.5% platinum content), heat to 80°C, react for 6h, cool after the reaction, and vacuum to remove unreacted trimethoxysilane to obtain a silicone-modified polyurethane prepolymer.

[0051] Preparation Example 4, a silicone-modified polyurethane prepolymer, which differs from Preparation Example 1 in that trimethoxysilane is replaced by an equal amount of terminal hydrogenated silicone oil, the terminal hydrogenated silicone oil is obtained from Runhe High-tech Materials, model RH-H6, hydrogen content 0.10-0.12%, viscosity 20-25 mm 2 / s.

[0052] Embodiment: Embodiment 1, a water-activated cold patch asphalt mixture is prepared according to the following steps:

[0053] Preparation of water-activated cold patch asphalt: 10 kg of 70# base asphalt, 2.3 kg of corn straw bio-oil, 3 kg of polyurethane prepolymer (isocyanate index 1.3), 1 kg of silicone-modified polyurethane prepolymer of Preparation Example 1, and 0.2 kg of vinyl trimethoxysilane water remover.

[0054] Preparation of water-activated cold patch asphalt mixture: Mix 100kg of continuously graded AC-13 crushed stone aggregate, 0.6kg of calcium oxide, 1.6kg of P.O42.5 cement and 5kg of the water-activated cold patch asphalt prepared above, and stir until the asphalt evenly coats the aggregate and there is no white material.

[0055] Example 2, a water-activated cold patch asphalt mixture, is prepared according to the following steps:

[0056] Preparation of water-activated cold patch asphalt: 10 kg of 90# base asphalt, 2.8 kg of corn straw bio-oil, 3.15 kg of polyurethane prepolymer (isocyanate index 1.2), 1.35 kg of silicone-modified polyurethane prepolymer of Preparation Example 2, and 0.3 kg of vinyl trimethoxysilane water remover.

[0057] Preparation of water-activated cold patch asphalt mixture: Mix 100kg of continuously graded AC-13 crushed stone aggregate, 0.6kg of calcium oxide, 1.4kg of P.O42.5 cement and 4.2kg of the water-activated cold patch asphalt prepared above, and stir until the asphalt evenly coats the aggregate and there is no white material.

[0058] Example 3, a water-activated cold patch asphalt mixture is prepared according to the following steps:

[0059] Preparation of water-activated cold patch asphalt: 10 kg of 70# base asphalt, 2.3 kg of rice husk bio-oil, 2.1 kg of polyurethane prepolymer (isocyanate index 1.5), 0.9 kg of silicone-modified polyurethane prepolymer of Preparation Example 3, and 0.2 kg of vinyl trimethoxysilane dewatering agent.

[0060] Preparation of water-activated cold patch asphalt mixture: Mix 100kg of continuously graded AC-13 crushed stone aggregate, 0.4kg of calcium oxide, 1.0kg of P.O42.5 cement and 6kg of the water-activated cold patch asphalt prepared above, and stir until the asphalt evenly coats the aggregate and there is no white material.

[0061] Example 4, a water-activated cold patch asphalt mixture, differs from Example 1 in that the organosilicon-modified polyurethane prepolymer of Preparation Example 1 is replaced by an equal amount of the organosilicon-modified polyurethane prepolymer of Preparation Example 4.

[0062] Example 5, a water-activated cold patch asphalt mixture, differs from Example 1 in that the P.O42.5 cement is replaced by an equal amount of the organosilicon-modified polyurethane prepolymer of Preparation Example 1.

[0063] Example 6, a water-activated cold patch asphalt mixture, differs from Example 1 in that no calcium oxide is added to the raw materials.

[0064] Comparative Example: Comparative Example 1, a water-activated cold patch asphalt mixture, differs from Example 1 in that the silicone-modified polyurethane prepolymer of Preparation Example 1 is replaced by an equal amount of polyurethane prepolymer (isocyanate index 1.3).

[0065] Comparative Example 2 is a water-activated cold patch asphalt mixture, which differs from Example 1 in that the polyurethane prepolymer (isocyanate index 1.3) is replaced by an equal amount of the organosilicon-modified polyurethane prepolymer of Preparation Example 1.

[0066] Performance test: 1. Initial strength: Weigh about 1200g of cold patch asphalt mixture (the specimen height is 63.5±1.3mm), put it into the test mold at room temperature, compact the specimen on both sides 75 times at -5℃, then demold it and conduct Marshall strength test according to the provisions of JTGE20-2011.

[0067] 2. Forming strength: Weigh 1180g of cold patch asphalt mixture and put it into a test mold at room temperature (the test piece height is 63.5±1.3mm), compact it 50 times on both sides, and place it and the test mold in a 110℃ constant temperature box in an upright position for 24 hours. Then compact it 25 times on both sides. After compaction, stand the test mold upright at room temperature for 2 days, then demold it and place it in a 60℃ constant temperature box for 1 day, then cure it at room temperature for 7 days, and determine the Marshall strength value according to the provisions of JTG E20-2011.

[0068] 3. Marshall stability after immersion in water: The stability is obtained by conducting a Marshall test in accordance with the provisions of JTGE20-2011 after immersion in water for 48 hours at the specified temperature (60°C).

[0069] 4. Shear strength: According to the provisions of JTG E20-2011, apply horizontal shear force to the composite specimen at a temperature of 20-25℃ and a loading rate of 2mm / min until the specimen is sheared and damaged. Record the maximum shear force at the time of damage, and calculate the shear strength by the formula, which is equal to the maximum shear force divided by the area of ​​the shear surface.

[0070] 5. Adhesion: The adhesion of cold patch asphalt mixture was tested by water boiling method. The test showed that the adhesion grade was 5, which met the use requirements.

[0071] 6. Freeze-thaw splitting strength ratio: The asphalt mixture specimens are subjected to freeze-thaw cycles under the conditions specified in JTG E20-2011, and the splitting strength ratio of the mixture specimens before and after water damage is measured to evaluate the water stability of the asphalt mixture. Unless otherwise specified, the test temperature is 25°C and the loading rate is 50mm / min.

[0072] 7. Dynamic stability

[0073] According to JTG E20-2011, the plate-shaped specimens with a length of 300mm, a width of 300mm and a thickness of 50-100mm are rolled and formed by a wheel rolling machine. Specimens of other sizes can also be used according to the needs of the project. It is also suitable for on-site cutting of plate-shaped specimens. The size of the cut specimens is determined by the test according to the actual situation of the on-site surface layer. The dynamic stability test of the mixture is carried out. Unless otherwise specified, the test temperature is 60℃ and the wheel pressure is 0.7MPa. According to needs, 45℃ can also be used in cold areas, and 70℃ can be used under high temperature conditions. The wheel pressure for heavy-load traffic can be increased to 1.4MPa, but it should be noted in the report. In principle, the time for calculating dynamic stability is between 45 and 60 minutes after the start of the test.

[0074] 8. Low temperature bending failure strain

[0075] According to JTG E20-2011, the strain rate of bending creep of water-activated cold patch asphalt mixture specimens under specified temperature and loading stress level conditions was measured to evaluate the deformation performance of asphalt mixture.

[0076] Table 1. Test results

[0077]

[0078] It can be seen from Examples 1-6 and Comparative Examples 1-2 and Table 1 that in water-activated cold patch asphalt, the use of conventional polyurethane prepolymers and the silicone-modified polyurethane prepolymers of the present application as curing agents can achieve a balance between the water damage resistance (residual stability, freeze-thaw splitting characterization) and strength performance (Marshall stability) of the asphalt mixture. Among them, conventional polyurethane prepolymers are used to ensure the water-activated curing speed, which is conducive to shortening the strength formation time, achieving rapid curing of the asphalt mixture, and ensuring construction performance. The silicone-modified polyurethane prepolymer can enhance its water damage resistance, but will slow down the curing rate to a certain extent. At the same time, the silicone-modified polyurethane prepolymer improves the bonding strength between the asphalt mixture and the roadbed (characterized by shear strength).

[0079] It should be noted that after being immersed in water, the residual unreacted active groups of the polyurethane prepolymer curing agent used in the present application will undergo deep cross-linking and curing. Combined with the positive effect of the silicone polyurethane prepolymer in resisting water damage, there is a probability that the Marshall stability after immersion in water will be further improved, thereby making its residual stability higher than 100%.

[0080] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A water-activated cold patch asphalt, characterized in that: The invention comprises the following raw materials in parts by weight: 100 parts of base asphalt, 20-30 parts of bio-oil diluent, 30-45 parts of polyurethane prepolymer, 1-5 parts of water remover; The polyurethane prepolymer comprises a main polyurethane prepolymer and an organosilicon-modified polyurethane prepolymer, wherein the organosilicon-modified polyurethane prepolymer accounts for 20 to 30 wt %; the organosilicon-modified polyurethane prepolymer is prepared by a polyurethane prepolymer containing a carbon-carbon double bond and a siloxane compound containing a silicon hydrogen group in a mass ratio of 15 to 25:1, and a silicon hydrogen group-containing siloxane compound is selected from at least one of trimethoxysilane, triethoxysilane, methyldimethoxysilane and ethyldimethoxysilane; The polyurethane prepolymer containing carbon-carbon double bonds is obtained by reacting polyether polyol, hydroxyl-containing acrylic compound and polyisocyanate, the molar ratio of isocyanate group to hydroxyl group in the polyether polyol, hydroxyl-containing acrylic compound and polyisocyanate is 1.1-1.3, and the molar ratio of the polyether polyol to the hydroxyl-containing acrylic compound is 1:2-3.

2. The water-activated cold patch asphalt according to claim 1, characterized in that: The isocyanate index of the main polyurethane prepolymer is 1.2 to 1.

5.

3. The water-activated cold patch asphalt according to claim 1, characterized in that: The hydroxyl-containing acrylic compound is selected from one or more of hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, and hydroxybutyl acrylate.

4. The water-activated cold patch asphalt according to claim 1, characterized in that: The polyisocyanate is selected from at least one of toluene diisocyanate, hexamethylene diisocyanate, hydrogenated diphenylmethane diisocyanate, diphenylmethane diisocyanate and isophorone diisocyanate.

5. A water-activated cold patch asphalt mixture, characterized in that: Contains the following components by weight: 100 parts of the water-activated cold patch asphalt according to any one of claims 1 to 4, 100 parts of aggregate, 1 to 2 parts of water-activated accelerator, and 0.5 to 1 part of calcium oxide; the water-activated accelerator is cement.

6. A method for preparing a water-activated cold patch asphalt mixture, characterized in that: include: According to the mixture ratio of claim 5, aggregate, calcium oxide, water-activated accelerator and water-activated cold patch asphalt are mixed and stirred until the asphalt evenly coats the aggregate and no white material is obtained.

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