Preparation method of water-activated cold patch asphalt mixture

Abstract

The invention discloses a preparation method of a water-activated cold patch asphalt mixture, which adopts a two-step method for preparation and specifically comprises preparation of water-activated cold patch asphalt and preparation of the water-activated cold patch asphalt mixture, and when the mixture is used, water needs to be added as a reaction medium for activation; the concrete proportion of all the components is as follows in percentage by mass. According to the preparation method of the water-activated cold patch asphalt mixture, the isomerized tetradecane, the light white oil, the methyl palmitate, the isoprene oligomer and the polyethylene glycol monomethyl ether stearate are added to optimize the rheological property of the cold patch asphalt, and meanwhile, the slaked lime is introduced as an active component; water is used as an activating agent to trigger chemical reaction among the slaked lime, the methyl palmitate, the isoprene oligomer and the polyethylene glycol monomethyl ether stearate, the curing process of the mixture is accelerated, and the technical effects of quick setting, early strength, high compactness and good water resistance are achieved.

Description

Technical Field

[0001] This invention relates to the field of asphalt mixture technology, and specifically to a method for preparing water-activated cold patch asphalt mixture. Background Technology

[0002] During long-term service, asphalt pavements are prone to potholes and cracks due to repeated vehicle loads and environmental factors (such as temperature changes and rainwater erosion). Among these, potholes are a typical form of pavement damage. If not repaired in time, the damaged area will expand rapidly, affecting road safety and comfort, and increasing later maintenance costs.

[0003] Currently, the commonly used materials for pothole repair on asphalt pavements mainly include hot-mix asphalt mixtures and traditional cold-patch asphalt mixtures. Hot-mix asphalt mixtures have advantages such as high strength and good road performance, but they also have problems such as requiring on-site heating for construction, high energy consumption, and significant limitations in construction due to temperature and time constraints, making them particularly unsuitable for low temperatures, rainy weather, or emergency repair scenarios. Traditional cold-patch asphalt mixtures, while requiring no heating and being convenient to apply, generally suffer from low early strength, slow curing speed, and poor water resistance, making them prone to secondary damage after repair and unable to meet the requirements of rapid traffic reopening and long-term use.

[0004] To address the aforementioned issues, related technologies have attempted to improve the performance of cold-patch asphalt mixtures by optimizing component ratios. However, most solutions suffer from problems such as complex compositions, poor environmental friendliness, or demanding activation conditions. Therefore, developing a simple, environmentally friendly method for preparing cold-patch asphalt mixtures that achieves rapid setting, early strength, high density, and good water resistance is of significant practical importance for pothole repair in asphalt pavements. Summary of the Invention

[0005] In view of the deficiencies of the prior art, the purpose of this invention is to provide a method for preparing water-activated cold-mix asphalt mixture, so as to solve the problems mentioned in the background art.

[0006] The present invention solves the technical problem by adopting the following technical solution: This invention provides a method for preparing water-activated cold-patch asphalt mixture, employing a two-step preparation method, specifically including the preparation of water-activated cold-patch asphalt and the preparation of water-activated cold-patch asphalt mixture. Water is added as a reaction medium to activate the mixture before use. The specific proportions of each component by mass percentage are as follows: Water-activated cold patching asphalt: 100 parts of No. 90 base asphalt, 8-12 parts of isotetradecane, 4-6 parts of light white oil, 8-12 parts of methyl palmitate, 3-5 parts of isoprene oligomer, and 2-4 parts of polyethylene glycol monomethyl ether stearate. Water-activated cold patch asphalt mixture: 100 parts aggregate, 4-5 parts of the above water-activated cold patch asphalt, and 1-2 parts hydrated lime; Reaction medium water: Add 2-3 parts when using.

[0007] Preferably, the viscosity of the isotetradecane at 25°C is about 3-5 mPa·s; The light white oil has a flash point ≥130℃ and a kinematic viscosity ≤3.5 mm at 40℃. 2 / s, widely available and low cost; the flash point of the methyl hexadecanoate is ≥150℃; The isoprene oligomer has a flash point ≥140℃ and a molecular weight range of 500-800. The polyethylene glycol monomethyl ether stearate has a flash point ≥160℃ and an HLB value of 10-12.

[0008] Preferably, the specific preparation steps are as follows: Step 1: Heat the No. 90 base asphalt to 120℃~130℃ and keep it warm until needed; Step 2: Add isotetradecane, light white oil, methyl palmitate, isoprene oligomer, and polyethylene glycol monomethyl ether stearate to the base asphalt prepared in Step 1, and stir evenly to make water-activated cold patch asphalt. Step 3: Mix the aggregate with the water-activated cold patch asphalt prepared in Step 2 in a certain proportion to make a water-activated cold patch asphalt mixture.

[0009] Preferably, in step two, the stirring speed is 300~500 r / min, the stirring time is 15~20 min, and the temperature of the base asphalt is maintained at 110℃~120℃ during the stirring process; in step three, the mixing time of aggregate and water-activated cold patch asphalt is 2~3 min.

[0010] Preferably, 10-15 parts of modified filler are also added to the water-activated cold patch asphalt mixture; The modified filler is a composite system of nano-calcium carbonate and metakaolin, with a mass ratio of 1:1 to 2:1; wherein the nano-calcium carbonate has a particle size of 50 to 100 nm and a specific surface area ≥ 30 m². 2 / g, whiteness ≥93%; metakaolin is calcined kaolin, calcined at 700~800℃, with active alumina content ≥35%, and specific surface area ≥20m². 2 / g; The composite system also incorporates modified liquid ball milling for improvement. The specific improvement method is as follows: Add 10-15% of the total amount of nano-calcium carbonate to the composite system of nano-calcium carbonate and metakaolin, and ball mill for 1-2 hours at a speed of 1000-1500 r / min. After ball milling, filter and dry. The modification solution comprises the following raw materials in parts by weight: 2-5 parts lanthanum oxide, 1-3 parts nanocellulose, 3-5 parts sodium silicate solution with a mass fraction of 5%, and 2-5 parts barium nitrate solution with a mass fraction of 2%.

[0011] Preferably, the aggregate is available in two sizes: 5mm~10mm and 0~5mm, with a mass ratio of 70:30 between the two sizes. The aggregate quality should comply with the relevant provisions of the "Technical Specification for Construction of Asphalt Pavement of Highway" (JTG F40-2004).

[0012] Preferably, the slaked lime is industrial grade slaked lime with a Ca(OH)2 content ≥90%.

[0013] Preferably, when using the water-activated cold patch asphalt mixture, quicklime is added and quickly mixed for 1-2 minutes. The uniformly mixed cold patch asphalt mixture is then poured into a mold, water is sprayed on the surface, and then it is compacted or rolled to obtain water-activated cold patch asphalt mixture specimens for performance tests such as Marshall stability, water immersion Marshall residual stability, freeze-thaw splitting strength ratio, and 60℃ rutting test.

[0014] Preferably, the amount of water sprayed is based on the weight of the cold-mixed asphalt mixture, which is 2 to 3 parts.

[0015] Preferably, the water-activated cold patch asphalt mixture has a construction temperature range of -10℃ to 40℃, a 24-hour Marshall stability of ≥15KN, and an internal porosity of ≤6% after compaction.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention discloses a method for preparing water-activated cold-patch asphalt mixtures. By adding isotetradecane, light white oil, methyl palmitate, isoprene oligomer, and polyethylene glycol monomethyl ether stearate, the rheological properties of cold-patch asphalt are optimized. Simultaneously, quicklime is introduced as an active component, and water is used as an activator to trigger the chemical reaction between quicklime and methyl palmitate, isoprene oligomer, and polyethylene glycol monomethyl ether stearate, thereby accelerating the curing process of the mixture and achieving the technical effects of rapid setting, early strength, high density, and good water resistance. Significant rapid setting and early strength effect: This invention optimizes the rheological properties of cold-mixed asphalt by adding isotetradecane, light white oil, methyl hexadecanoate, isoprene oligomer, and polyethylene glycol monomethyl ether stearate. At the same time, quicklime is introduced as an active component, and water is used as an activator to trigger the chemical reaction between quicklime and methyl hexadecanoate, isoprene oligomer, and polyethylene glycol monomethyl ether stearate, which accelerates the curing process of the mixture. The Marshall stability can reach more than 15KN in 24 hours, achieving rapid strength formation and meeting the needs of early traffic opening.

[0017] High density and good water resistance: During the water activation process, the components react fully, and the porosity inside the mixture can be controlled below 8%, significantly improving the density; at the same time, the reaction products form a stable coating layer on the surface of the aggregate, effectively blocking the intrusion of water and solving the problem that traditional cold-mixed materials are easily damaged by water.

[0018] Simple composition and environmentally friendly: The components used in this invention are all industrial-grade environmentally friendly materials, including light white oil and methyl palmitate, which do not release volatile harmful substances during use; compared with traditional cold patching materials, the use of a variety of chemical additives is reduced, the composition is simplified, and the impact on the environment is reduced.

[0019] Convenient construction and strong adaptability: The mixture can be stored at room temperature. When using it, it only needs to be activated by adding water. No complicated heating equipment is required. Construction is not limited by temperature and weather. It can be used normally in environments from -5℃ to 40℃. It is suitable for emergency repair and daily maintenance of potholes in various asphalt pavements. The modified solution contains nanocellulose, which has a high aspect ratio and surface activity. It can be adsorbed on the surface of nano-calcium carbonate and metakaolin particles, forming a steric hindrance effect and hindering particle aggregation. The colloidal properties of sodium silicate solution have a wetting effect, which can reduce the interfacial tension between filler particles and further disperse them. The "skeleton filling" effect of the modified filler, combined with the CSH gel generated by the hydration reaction and the "cementing and strengthening" effect of the insoluble barium salt, form a high-strength load-bearing system. Lanthanum oxide (a rare earth element oxide) in the modified solution can catalyze the hydration reaction rate and promote the early formation of gelling substances. Combined with the reaction acceleration effect of polyethylene glycol monomethyl ether stearate, the water activation reaction is more complete and faster. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to specific examples. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] This embodiment describes a method for preparing a water-activated cold-patch asphalt mixture, employing a two-step process. Specifically, it includes the preparation of water-activated cold-patch asphalt and the preparation of the water-activated cold-patch asphalt mixture. Water is added as a reaction medium to activate the mixture before use. The specific proportions of each component, by mass percentage, are as follows: Water-activated cold patching asphalt: 100 parts of No. 90 base asphalt, 8-12 parts of isotetradecane, 4-6 parts of light white oil, 8-12 parts of methyl palmitate, 3-5 parts of isoprene oligomer, and 2-4 parts of polyethylene glycol monomethyl ether stearate. Water-activated cold patch asphalt mixture: 100 parts aggregate, 4-5 parts of the above water-activated cold patch asphalt, and 1-2 parts hydrated lime; Reaction medium water: Add 2-3 parts when using.

[0022] The viscosity of the isotetradecane in this embodiment is approximately 3-5 mPa·s at 25°C. The light white oil has a flash point ≥130℃ and a kinematic viscosity ≤3.5 mm at 40℃. 2 / s, widely available and low cost; the flash point of the methyl hexadecanoate is ≥150℃; The isoprene oligomer has a flash point ≥140℃ and a molecular weight range of 500-800. The polyethylene glycol monomethyl ether stearate has a flash point ≥160℃ and an HLB value of 10-12.

[0023] The specific preparation steps in this embodiment are as follows: Step 1: Heat the No. 90 base asphalt to 120℃~130℃ and keep it warm until needed; Step 2: Add isotetradecane, light white oil, methyl palmitate, isoprene oligomer, and polyethylene glycol monomethyl ether stearate to the base asphalt prepared in Step 1, and stir evenly to make water-activated cold patch asphalt. Step 3: Mix the aggregate with the water-activated cold patch asphalt prepared in Step 2 in a certain proportion to make a water-activated cold patch asphalt mixture.

[0024] In step two of this embodiment, the stirring speed is 300~500 r / min, the stirring time is 15~20 min, and the temperature of the base asphalt is maintained at 110℃~120℃ during the stirring process; in step three, the mixing time of aggregate and water-activated cold patch asphalt is 2~3 min.

[0025] In this embodiment, 10-15 parts of modified filler are also added to the water-activated cold patch asphalt mixture; The modified filler is a composite system of nano-calcium carbonate and metakaolin, with a mass ratio of 1:1 to 2:1; wherein the nano-calcium carbonate has a particle size of 50 to 100 nm and a specific surface area ≥ 30 m². 2 / g, whiteness ≥93%; metakaolin is calcined kaolin, calcined at 700~800℃, with active alumina content ≥35%, and specific surface area ≥20m². 2 / g; The composite system also incorporates modified liquid ball milling for improvement. The specific improvement method is as follows: Add 10-15% of the total amount of nano-calcium carbonate to the composite system of nano-calcium carbonate and metakaolin, and ball mill for 1-2 hours at a speed of 1000-1500 r / min. After ball milling, filter and dry. The modification solution comprises the following raw materials in parts by weight: 2-5 parts lanthanum oxide, 1-3 parts nanocellulose, 3-5 parts sodium silicate solution with a mass fraction of 5%, and 2-5 parts barium nitrate solution with a mass fraction of 2%.

[0026] In this embodiment, the aggregates are available in two sizes: 5mm~10mm and 0~5mm, with a mass ratio of 70:30. The aggregate quality should comply with the relevant provisions of the "Technical Specification for Construction of Asphalt Pavement of Highway" (JTG F40-2004).

[0027] The slaked lime in this embodiment is industrial-grade slaked lime with a Ca(OH)2 content ≥90%.

[0028] In this embodiment, when using the water-activated cold patch asphalt mixture, quicklime is added and quickly mixed for 1-2 minutes. The uniformly mixed cold patch asphalt mixture is then poured into a mold, water is sprayed on the surface, and then it is compacted or rolled to obtain water-activated cold patch asphalt mixture specimens for performance tests such as Marshall stability, water immersion Marshall residual stability, freeze-thaw splitting strength ratio, and 60℃ rutting test.

[0029] The amount of water sprayed in this embodiment is based on the weight of the cold-mixed asphalt mixture, which is 2 to 3 parts.

[0030] The construction temperature range of the water-activated cold patch asphalt mixture in this embodiment is -10℃ to 40℃, the 24h Marshall stability is ≥15KN, and the internal porosity of the compacted mixture is ≤6%.

[0031] Example 1: A method for preparing water-activated cold-mix asphalt mixture, the specific steps of which are as follows: 1. Preparation of water-activated cold patch asphalt: Take 100 kg of No. 90 base asphalt and heat it to 120℃ and keep it at that temperature; add 8 kg of isotetradecane, 4 kg of light white oil, 8 kg of methyl palmitate, 3 kg of isoprene oligomer and 2 kg of polyethylene glycol monomethyl ether stearate to it, stir at 300 r / min for 15 min, and after mixing evenly, water-activated cold patch asphalt is obtained.

[0032] 2. Aggregate pretreatment: Select two types of aggregates, 5~10mm and 0~5mm, and mix them in a ratio of 80:20 to form continuous graded basalt aggregates. Dry them until the moisture content is ≤0.5%.

[0033] 3. Mixing of the mixture: Take 100 kg of pretreated aggregate and put it into the mixer, add 4 kg of the above-mentioned water-activated cold patch asphalt, mix for 2 minutes, and discharge to obtain water-activated cold patch asphalt mixture.

[0034] 4. On-site application: Take the above mixture, add 1 kg of industrial-grade hydrated lime (Ca(OH)2 content 92%), mix quickly for 1 minute, fill it into the potholes of the asphalt pavement, then spray 2 kg of water onto the surface of the potholes and compact it into shape.

[0035] The mixture was tested and found to have a 24-hour Marshall stability of 15.6 kN.

[0036] Example 2: A method for preparing water-activated cold-mix asphalt mixture, the specific steps of which are as follows: 1. Preparation of water-activated cold patch asphalt: Take 100 kg of No. 90 base asphalt and heat it to 125℃ and keep it at that temperature; add 10 kg of isotetradecane, 5 kg of light white oil, 10 kg of methyl hexadecanoate, 4 kg of isoprene oligomer and 3 kg of polyethylene glycol monomethyl ether stearate to it, stir at 400 r / min for 18 min, and after mixing evenly, water-activated cold patch asphalt is obtained.

[0037] 2. Aggregate pretreatment: Select two types of aggregates, 5~10mm and 0~5mm, and mix them in a ratio of 75:25 to form continuous graded limestone aggregates, and dry them until the moisture content is ≤0.5%.

[0038] 3. Mixing of the mixture: Take 100kg of pretreated aggregate and put it into the mixer, add 4.5kg of the above-mentioned water-activated cold patch asphalt, mix for 3 minutes, and discharge to obtain water-activated cold patch asphalt mixture.

[0039] 4. On-site application: Take the above mixture, add 1.5 kg of industrial-grade hydrated lime (Ca(OH)2 content 91%), mix quickly for 1.5 min, fill it into the potholes of the asphalt pavement, then spray 2.5 kg of water onto the surface of the potholes and compact it into shape.

[0040] The Marshall stability of the mixture was tested and found to be 17.3 kN.

[0041] Example 3: A method for preparing water-activated cold-mix asphalt mixture, the specific steps of which are as follows: 1. Preparation of water-activated cold patch asphalt: Take 100 kg of No. 90 base asphalt and heat it to 130℃ and keep it at that temperature; add 12 kg of isotetradecane, 6 kg of light white oil, 12 kg of methyl hexadecanoate, 5 kg of isoprene oligomer and 4 kg of polyethylene glycol monomethyl ether stearate to it, stir at 500 r / min for 20 min, and after mixing evenly, water-activated cold patch asphalt is obtained.

[0042] 2. Aggregate pretreatment: Select two types of aggregates, 5~10mm and 0~5mm, and mix them in a 70:30 ratio to form continuous graded basalt aggregates. Dry them until the moisture content is ≤0.5%.

[0043] 3. Mixing of the mixture: Take 100 kg of pretreated aggregate and put it into the mixer, add 5 kg of the above-mentioned water to activate the cold patch asphalt, continue mixing for 4 minutes, and discharge to obtain the water-activated cold patch asphalt mixture.

[0044] 4. On-site application: Take the above mixture, add 2kg of industrial-grade hydrated lime (Ca(OH)2 content 93%), mix quickly for 2 minutes, fill it into the potholes of the asphalt pavement, then spray 3kg of water onto the surface of the potholes and compact it into shape.

[0045] The mixture was tested and found to have a 24-hour Marshall stability of 19.1 kN.

[0046] To verify the beneficial effects of the product of this invention, the performance of the water-activated cold patch asphalt mixture prepared in the three embodiments of this invention was compared with that of traditional cold patch material. The comparison results are shown in the table below:

[0047] The comparison results show that the water-activated cold patch asphalt mixture prepared by the present invention is significantly superior to the traditional cold patch asphalt mixture in terms of density, strength, water stability, and high-temperature rutting resistance.

[0048] In Optimized Example 1, based on Example 3, 12.5 parts of modified filler were added to the water-activated cold patch asphalt mixture; The modified filler is a composite system of nano-calcium carbonate and metakaolin, with a mass ratio of 1:1; wherein the nano-calcium carbonate has a particle size of 70nm and a specific surface area ≥30m². 2 / g, whiteness ≥93%; metakaolin is calcined kaolin, calcined at 750℃, with active alumina content ≥35%, and specific surface area ≥20m². 2 / g; The composite system also incorporates modified liquid ball milling for improvement. The specific improvement method is as follows: Add a modification liquid containing 12.5% ​​of the total amount of nano-calcium carbonate to the composite system of nano-calcium carbonate and metakaolin, and ball mill for 1.5 hours at a speed of 1250 r / min. After ball milling, filter and dry the mixture. The modification solution comprises the following raw materials in parts by weight: 3.5 parts lanthanum oxide, 2 parts nanocellulose, 4 parts sodium silicate solution with a mass fraction of 5%, and 3.5 parts barium nitrate solution with a mass fraction of 2%.

[0049] The product performance test results for Optimized Example 1 are as follows:

[0050] The innovation of this invention lies in the addition of a modified filler to the water-activated cold-mix asphalt mixture. Through the addition of the modified filler, the overall performance of the product is improved in a coordinated manner, the performance of the product is further optimized, and the scope of application is further improved.

[0051] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0052] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method of preparing a water-activated cold patch asphalt mixture, characterized in that, The water-activated cold patch asphalt is prepared by a two-step method, specifically including preparation of water-activated cold patch asphalt and preparation of water-activated cold patch asphalt mixture, and water is added as a reaction medium to activate the mixture when used. The water-activated cold patch asphalt comprises 100 parts of No. 90 base asphalt, 8-12 parts of isohexadecane, 4-6 parts of light white oil, 8-12 parts of methyl hexadecanoate, 3-5 parts of isoprene oligomer and 2-4 parts of polyethylene glycol monomethyl ether stearate. The water-activated cold patch asphalt mixture comprises 100 parts of aggregate, 4-5 parts of the water-activated cold patch asphalt and 1-2 parts of slaked lime. The reaction medium water is added in an amount of 2-3 parts when used.

2. The production method according to claim 1, characterized by, The isohexadecane has a viscosity of about 3-5 mPa·s at 25℃. The light white oil has a flash point ≥ 130℃ and a 40℃ kinematic viscosity ≤ 3.5mm 2 / s, wide sources, low cost; the methyl cetylate has a flash point ≥ 150℃; The isoprene oligomer has a flash point of ≥140℃ and a molecular weight of 500-800. The polyethylene glycol monomethyl ether stearate has a flash point of ≥160℃ and an HLB value of 10-12.

3. The preparation method according to claim 1, characterized in that, The preparation steps are as follows: Step one: heat the No. 90 base asphalt to 120-130℃ and keep warm; Step two: add the isohexadecane, light white oil, methyl hexadecanoate, isoprene oligomer and polyethylene glycol monomethyl ether stearate into the base asphalt kept warm in step one, and stir to prepare the water-activated cold patch asphalt; Step three: mix the aggregate with the water-activated cold patch asphalt prepared in step two to prepare the water-activated cold patch asphalt mixture.

4. The preparation method according to claim 3, characterized in that, The stirring speed in step two is 300-500 r / min, the stirring time is 15-20 min, and the temperature of the base asphalt is kept at 110-120℃ during the stirring; the mixing time of the aggregate and the water-activated cold patch asphalt in step three is 2-3 min.

5. The preparation method according to claim 3, characterized in that, 10-15 parts of modified filler are added to the water-activated cold patch asphalt mixture. The modified filler is a composite system of nano calcium carbonate and metakaolin, and the mass ratio is 1:1-2:1; wherein the particle size of the nano calcium carbonate is 50-100 nm, the specific surface area is greater than or equal to 30 m 2 / g, and the whiteness is greater than or equal to 93%; the metakaolin is calcined kaolin, the calcination temperature is 700-800 DEG C, the active alumina content is greater than or equal to 35%, and the specific surface area is greater than or equal to 20 m 2 / g. A modified liquid is added to the composite system for ball milling, and the specific improvement method is as follows: Add the modified liquid to the composite system of nano calcium carbonate and metakaolin, and ball mill for 1-2 h at a speed of 1000-1500 r / min, then filter and dry. The modified liquid comprises the following raw materials by weight: 2-5 parts of lanthanum oxide, 1-3 parts of nano cellulose, 3-5 parts of a 5% sodium silicate solution and 2-5 parts of a 2% barium nitrate solution.

6. The method of claim 1, wherein, The aggregate has two specifications of 5-10 mm and 0-5 mm, and the mass ratio of the two specifications is 70:30, and the aggregate mass shall meet the relevant provisions of the Technical Specification for Construction of Highway Asphalt Pavement (JTG F40-2004).

7. The preparation method according to claim 1, characterized in that, The slaked lime is an industrial-grade slaked lime with a Ca(OH)2 content of ≥90%.

8. The method of claim 1, wherein, When the water-activated cold patch asphalt mixture is used, the slaked lime is added and quickly mixed for 1-2 min, then the mixed cold patch asphalt mixture is loaded into a test mold, water is sprayed on the surface, and then the mixture is compacted or rolled to form a water-activated cold patch asphalt mixture test piece, which is used for performance tests such as Marshall stability, immersion Marshall residual stability, freeze-thaw splitting strength ratio, 60℃ rutting test, etc.

9. The method of claim 1, wherein, The spraying amount of water is 2-3 parts based on the weight of the cold patch asphalt mixture.

10. The method of claim 1, wherein, The construction temperature range of the water-activated cold patch asphalt mixture is -10 DEG C to 40 DEG C, the 24h Marshall stability is greater than or equal to 15KN, and the internal void ratio of the mixture after compaction is less than or equal to 6%.

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