Latent curing type high-strength and high-modulus cold patch asphalt mixture and preparation method thereof

Abstract

The invention discloses a latent curing type high-strength and high-modulus cold patch asphalt mixture and a preparation method thereof. The cold patch asphalt mixture is prepared from the following substances in percentage by mass: 7 to 10 weight percent of composite emulsified asphalt, 1.5 to 5.5 weight percent of magnesium phosphate cementing material, 0.5 to 3.5 weight percent of latent curing agent, 1.5 to 5.5 weight percent of water-borne epoxy resin and 78 to 88 weight percent of aggregate. The preparation method comprises the following steps: preparing composite emulsified asphalt, a magnesium phosphate cementing material and a latent curing agent; uniformly mixing the water-borne epoxy resin and the composite emulsified asphalt to obtain emulsified asphalt cold supplementing liquid; and sequentially putting the dried aggregate with each grade of particle size, the emulsified asphalt cold patch liquid, the magnesium phosphate cementing material and the latent curing agent into a mixer for stirring to obtain the latent curing type high-strength and high-modulus cold patch asphalt mixture. According to the invention, the modulus and strength of the cold patch asphalt mixture can be improved in severe environments of high humidity, rain, snow and cold.

Description

Technical Field

[0001] The invention belongs to the technical field of road construction material design and preparation, and specifically relates to a latent curing high-strength and high-modulus cold patch asphalt mixture and a preparation method thereof. Background Art

[0002] With the rapid development of urban construction in my country, traffic volume has increased dramatically and road construction has developed rapidly, especially the mileage of expressways and second-level and above roads has reached one million kilometers. The extensive road network plays a key role in economic development, regional exchanges and people's lives.

[0003] With the increase in traffic volume and the changeable climatic conditions, the problem of road surface damage (such as potholes, cracks, etc.) is becoming increasingly serious, and the intensity of road maintenance is also increasing. Especially in the harsh environment of high humidity, rain, snow and cold, road maintenance is difficult due to the influence of factors such as repair materials and environmental conditions.

[0004] During road construction and maintenance, the performance of road repair materials has an important impact on the service life of the road and driving safety. The road repair materials in the existing technology mainly include hot-mix asphalt mixture and cold-patch asphalt mixture, and both of these road repair materials have certain defects. Hot-mix asphalt mixture needs to be heated on site during repair, which not only increases maintenance costs and labor intensity, but is also greatly affected by weather and temperature. A high construction temperature needs to be maintained during the repair process. It is mostly used to repair pavement in summer. If repaired in a low temperature environment, it is difficult to achieve the ideal compaction and strength, resulting in the early damage of the repaired pavement; in addition, hot-mix asphalt mixture will produce a large amount of smoke and harmful gases during the repair process, causing environmental pollution. Cold-patch asphalt mixture has far greater advantages than hot-mix asphalt mixture in terms of environmental adaptability, repair procedures, material storage and transportation, and does not produce high-temperature harmful gases. It is currently the preferred material for road repair. However, the use of cold-patch asphalt mixture to repair pavement in harsh environments such as high humidity, rain, snow, and cold weather has slow curing speed, low modulus, and insufficient strength development. Therefore, the repaired pavement is prone to falling off and damage under heavy traffic and harsh weather conditions, which affects the repair quality and service life of the road, and also limits the application of cold-patch asphalt mixture in extreme weather conditions.

[0005] In the research field of cold-patch asphalt mixtures, industry experts and scholars have been exploring how to improve the performance of cold-patch asphalt mixtures, especially the curing speed and adhesion under high humidity, rain, snow, and cold conditions. The cold-patch asphalt mixtures in the prior art are usually composed of binders, aggregates, mineral powder, diluents, etc. The improvement of their curing strength mainly depends on the volatilization of diluents, but this process is usually slow, which will cause the adhesion and strength of the cold-patch asphalt mixture to fail to reach the ideal value within a period of time after construction, and it is easy to peel and fall off. Under the immersion and scouring of rainwater, it is also easy to be taken away by the wheels, greatly reducing the road repair effect. Therefore, it is urgent to develop a latent curing high-strength and high-modulus cold-patch asphalt mixture and its preparation method, and form a fast and reasonable curing system through magnesium phosphate cementitious materials, epoxy resins and latent curing agents to achieve the effects of improving the modulus and strength of cold-patch asphalt mixtures in harsh environments of high humidity, rain, snow, and cold.

[0006] The invention patent with application publication number CN113526906A discloses a preparation method and application of a latent curing cold-mix cold-paved asphalt mixture, which is composed of 5-8 parts of cold-mixed epoxy asphalt material and 100 parts of wet aggregate. The cold-mixed epoxy asphalt material is formed by mixing solvent-based room temperature modified asphalt with epoxy resin, cyanate prepolymer, latent curing agent, and curing accelerator. The curing agent is aliphatic polyamine, alicyclic polyamine or aromatic polyamine latent ketimine. Although this technical solution can improve the early curing strength and performance of the mixture, it is only suitable for repairing pavement under normal climatic conditions, and is not suitable for repairing pavement under extreme conditions such as high humidity, rain, snow, and cold.

[0007] The invention patent with application publication number CN117024054A discloses a reactive dilution type regenerated cold patch material suitable for use in severe rain and snow environments and its preparation method. The cold patch material includes the following raw materials by mass: 97-99 parts of asphalt pavement recycled material, 1-3 parts of mineral powder, 1-1.5 parts of fiber, and 4-6 parts of cold patch asphalt; the cold patch asphalt is made of asphalt, asphalt diluent, polyurethane, slaked lime and cement, and the mass ratio is asphalt: asphalt diluent: polyurethane: slaked lime: cement = 100: 25-32: 3-6: 2-5: 2-5. This technical solution modifies the cold patch liquid by adding polyurethane, cement and slaked lime, thereby improving the early strength and water stability of the cold patch material, but the curing speed of polyurethane is slow, the strength development is insufficient, and the pavement repair effect still needs to be improved. Summary of the invention

[0008] In order to solve the problems existing in the prior art, the present invention provides a latent curing high-strength and high-modulus cold patch asphalt mixture, wherein the mass percentage of each substance in the cold patch asphalt mixture is 7-10wt% of composite emulsified asphalt, 1.5-5.5wt% of magnesium phosphate gelling material, 0.5-3.5wt% of latent curing agent, 1.5-5.5wt% of water-based epoxy resin, and 78-88wt% of aggregate, and the sum of the contents of each substance is 100wt%.

[0009] Preferably, the mass percentage of each substance in the composite emulsified asphalt is 50-60wt% of base asphalt, 10-15wt% of cationic emulsifier, 2-5wt% of non-ionic emulsifier, 0.5-2.5wt% of stabilizer, 0.5-3.5wt% of kerosene, and 22-26wt% of water, and the sum of the contents of each substance is 100wt%; the solid content of the composite emulsified asphalt is not less than 75%.

[0010] In any of the above schemes, it is preferred that the base asphalt is No. 70 base asphalt and / or No. 90 base asphalt; the cationic emulsifier includes any one or more of cetyltrimethylammonium bromide, octadecyltrimethylammonium chloride, and dodecyltrimethylammonium chloride; the nonionic emulsifier includes any one or more of alkylphenol polyoxyethylene ether, fatty acid glyceride, and polyoxyethylene sorbitan ester; the stabilizer includes any one or more of anhydrous calcium chloride, magnesium sulfate, hydroxyethyl cellulose, and carboxymethyl cellulose.

[0011] In any of the above schemes, it is preferred that the mass percentage of each substance in the magnesium phosphate gelling material is 44-52wt% of dead-burned magnesium oxide, 14-18wt% of diammonium phosphate, 8-12wt% of fly ash, 8-12wt% of aluminum oxide, and 15-20wt% of mineral powder, and the sum of the contents of each substance is 100wt%.

[0012] In any of the above schemes, it is preferred that the particle size distribution of the dead-burned magnesium oxide is between 2-10 μm; the particle size distribution of the ammonium dihydrogen phosphate is between 30-100 μm, wherein the mass percentage of each particle size in the ammonium dihydrogen phosphate is 35wt% for a particle size of 75-100 μm, 35wt% for a particle size of 50-75 μm, and 30wt% for a particle size of 30-50 μm; the particle size distribution of the fly ash is between 20-100 μm, wherein each particle size is The mass percentage of the fly ash is: 75-100μm particle size accounts for 35wt%, 50-75μm particle size accounts for 35wt%, and 20-50μm particle size accounts for 30wt%; the particle size distribution of alumina is between 0.5-10μm; the particle size distribution of the mineral powder is between 0-75μm, and the mass percentage of each particle size of the mineral powder is: 50-75μm particle size accounts for 65wt%, and 0-50μm particle size accounts for 35wt%.

[0013] In any of the above schemes, it is preferred that the mass percentage of each substance in the latent curing agent is 40-50wt% of ketimine, 20-30wt% of polythiol, 10-20wt% of cardanol, 5-10wt% of acetone, and 5-10wt% of polyetheramine, and the sum of the contents of each substance is 100wt%.

[0014] In any of the above schemes, it is preferred that the waterborne epoxy resin is a cationic waterborne epoxy resin and / or a non-ionic waterborne epoxy resin, and the solid content of the waterborne epoxy resin is not less than 60%.

[0015] In any of the above schemes, it is preferred that the aggregate includes five particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 10-15wt%, particle size 9.5-13.2mm accounts for 25-30wt%, particle size 4.75-9.5mm accounts for 25-30wt%, particle size 2.36-4.75mm accounts for 20-25wt%, particle size 1.18-2.36mm accounts for 10-15wt%, and the aggregate includes any one or more of limestone, basalt, granite, and diabase.

[0016] The present invention also provides a method for preparing a latent curing high-strength and high-modulus cold-patch asphalt mixture, which is used to prepare the latent curing high-strength and high-modulus cold-patch asphalt mixture described in any one of the above items, and comprises the following steps in order:

[0017] Step 1: Weigh all raw materials according to the designed material ratio;

[0018] Step 2: preparing composite emulsified asphalt, magnesium phosphate gelling material and latent curing agent respectively according to the designed material ratio and process parameters;

[0019] Step 3: Add water-based epoxy resin to the composite emulsified asphalt and mix evenly to obtain emulsified asphalt cold make-up liquid;

[0020] Step 4: Put the aggregates of each particle size into the oven for drying;

[0021] Step 5: Put the dried aggregates of various particle sizes into the mixer for stirring. After stirring for a certain period of time, while keeping the stirring speed unchanged, put the emulsified asphalt cold patch liquid into the mixer and continue stirring. After continuing to stir for a certain period of time, increase the stirring speed, and at the same time put the magnesium phosphate cementitious material into the mixer and continue stirring. After continuing to stir for a certain period of time, while keeping the stirring speed unchanged, put the latent curing agent into the mixer and continue stirring to obtain a latent curing high-strength and high-modulus cold patch asphalt mixture.

[0022] Preferably, in step 2, the method for preparing the composite emulsified asphalt comprises the following steps in order:

[0023] Step (1): weigh and prepare the raw materials according to the designed material ratio;

[0024] Step (2): placing the matrix asphalt in a container, and then placing the container containing the matrix asphalt in an oil bath and heating it, while performing magnetic stirring until the matrix asphalt is completely melted and kept in a fluid state for standby use, the heating temperature is 85-90° C., the magnetic stirring speed is 2000-3000 r / min, and the magnetic stirring time is 20-30 min;

[0025] Step (3): putting the cationic emulsifier and the nonionic emulsifier into another container for compounding, and then adding 80-90wt% of water for magnetic stirring until they are fully dissolved to form a soap solution, the magnetic stirring speed is 1000-2000r / min, and the magnetic stirring time is 8-10min; putting the container containing the soap solution into an oil bath pot for heating, and keeping it warm for standby use, the heating temperature is 50-60°C, and the heating time is 10-15min;

[0026] Step (4): placing the stabilizer in another container, adding 10-20wt% of water and performing magnetic stirring until the stabilizer is fully dissolved in the water to form an aqueous solution for standby use, the magnetic stirring speed is 1000-2000r / min, and the magnetic stirring time is 8-10min; Step (5): placing kerosene in a container containing matrix asphalt and performing magnetic stirring, the heating temperature is 85-90°C, the magnetic stirring speed is 2000-3000r / min, and the magnetic stirring time is 10-20min;

[0027] Step (6): Place the soap solution and the aqueous solution into a container containing base asphalt and kerosene for shear stirring at a heating temperature of 85-90°C, a shear stirring speed of 1500-2000 r / min, and a shear stirring time of 20-30 min to obtain a composite emulsified asphalt, which is then sealed for later use.

[0028] In any of the above schemes, it is preferred that in step 2, the method for preparing the magnesium phosphate gelling material comprises the following steps in order:

[0029] Step (a): weigh and prepare the raw materials according to the designed material ratio;

[0030] Step (b): putting dead-burned magnesium oxide and aluminum oxide into a mixer and stirring them at room temperature, a stirring speed of 100-200 r / min, and a stirring time of 60-90 s;

[0031] Step (c): placing fly ash of various particle sizes into a mixer and continuing to stir at room temperature, a stirring speed of 200-300 r / min, and a stirring time of 90-150 s;

[0032] Step (d): placing the mineral powders of various particle sizes into a mixer and continuing to stir them at room temperature, a stirring speed of 200-300 r / min, and a stirring time of 90-150 s;

[0033] Step (e): placing diammonium hydrogen phosphate of various particle sizes into a mixer and continuing to stir at room temperature, a stirring speed of 200-300 r / min, and a stirring time of 90-150 s. After the stirring is completed, a mixture of the substances is obtained;

[0034] Step (f): placing the mixture of the substances in an oven for low-temperature drying at a temperature of 80-100° C. for 1-2 hours. After the drying is completed, a magnesium phosphate gelling material is obtained, which is sealed for later use.

[0035] In any of the above schemes, preferably, in step 2, the preparation method of the latent curing agent is to put ketimine, polythiol, cardanol, acetone and polyetheramine into a container according to the designed material ratio and mix them at room temperature to fully blend the substances, and then seal them for later use.

[0036] In any of the above schemes, preferably, in step 4, the drying temperature of aggregates of each particle size is 100-120° C., and the drying time is 2-3 hours.

[0037] In any of the above schemes, it is preferred that in step five, the stirring speed of the aggregate of each particle size after drying is 400-500r / min, and the stirring time is 60-90s; the emulsified asphalt cold make-up liquid is put into the mixer and continued to be stirred at a speed of 400-500r / min, and the stirring time is 60-90s; the magnesium phosphate cementitious material is put into the mixer and continued to be stirred at a speed of 500-800r / min, and the stirring time is 90-150s; the latent curing agent is put into the mixer and continued to be stirred at a speed of 500-800r / min, and the stirring time is 90-150s.

[0038] In any of the above schemes, it is preferred that in step five, before the latent curing type high-strength and high-modulus cold patch asphalt mixture is used in construction, a layer of emulsified asphalt cold patch liquid needs to be applied on the surface to be constructed, and at the same time, the surface of the latent curing type high-strength and high-modulus cold patch asphalt mixture needs to be sprayed with water to moisten it, and the amount of water sprayed is 0.1-0.5% of the latent curing type high-strength and high-modulus cold patch asphalt mixture.

[0039] In the present invention, the oven, mixer, oil bath, shear stirring equipment, magnetic stirring equipment, etc. used are all traditional equipment, and there are no special requirements for the equipment structure and model. It is only necessary to ensure that several key parameters such as drying temperature, drying time, stirring speed, stirring time, stirring temperature, etc. meet the requirements of the present invention.

[0040] In the present invention, the aggregate includes five particle sizes, namely, particle size 13.2-16mm, particle size 9.5-13.2mm, particle size 4.75-9.5mm, particle size 2.36-4.75mm, and particle size 1.18-2.36mm, that is, 13.2mm≤particle size<16mm, 9.5mm≤particle size<13.2mm, 4.75mm≤particle size<9.5mm, 2.36mm≤particle size<4.75mm, and 1.18mm≤particle size<2.36mm. The particle size distribution of dead-burned magnesium oxide is between 2-10μm, that is, 2μm≤particle size≤10μm. The particle size distribution of aluminum oxide is between 0.5-10μm, that is, 0.5μm≤particle size≤10μm. The particle size distribution of ammonium dihydrogen phosphate is between 30-100μm, including three particle sizes, namely, particle size 75-100μm, particle size 50-75μm, and particle size 30-50μm, that is, 75μm≤particle size≤100μm, 50μm≤particle size<75μm, and 30μm≤particle size<50μm. The particle size distribution of fly ash is between 20-100μm, including three particle sizes, namely, particle size 75-100μm, particle size 50-75μm, and particle size 20-50μm, that is, 75μm≤particle size≤100μm, 50μm≤particle size<75μm, and 20μm≤particle size<50μm. The particle size distribution of mineral powder is between 0-75μm, including two particle sizes, namely 50-75μm and 0-50μm, that is, 50μm≤particle size≤75μm, 0μm≤particle size<50μm. For each particle size, the material is passed through the upper and lower sieve holes in sequence to obtain a material with a particle size between the upper and lower sieve holes, for example: the particle size is 4.75-9.5mm (4.75mm≤particle size<9.5mm), that is, the material is passed through the 9.5mm sieve hole and the 4.75mm sieve hole in sequence to obtain a material with a particle size between 4.75-9.5mm.

[0041] In the present invention, the waterborne epoxy resin used is a cationic waterborne epoxy resin and / or a nonionic waterborne epoxy resin, and the solid content of the waterborne epoxy resin is not less than 60%, and there is no special requirement for the type of epoxy resin. The ketimine, polythiol and other substances used to prepare the latent curing agent can be selected from ketimine and polythiol substances, and there is no special requirement for the type. The mineral powder used is limestone.

[0042] In the preparation process of the cold patch asphalt mixture of the present invention, the selection of each substance, the mass percentage of each substance, the order of addition of each substance, the process parameters of each step, etc. are all very important. At the same time, in the preparation process of composite emulsified asphalt, magnesium phosphate cementitious material, and latent curing agent, the selection of each substance, the mass percentage of each substance, the order of addition of each substance, the process parameters of each step, etc. are also very important. The various formula parameters and process parameters need to work synergistically to achieve the expected technical effect of the present invention.

[0043] In the present invention, magnesium phosphate gelling material, water-based epoxy resin and latent curing agent form a fast and reasonable curing system. After the latent curing agent is mixed with the water-based epoxy resin, it has a certain storage stability at room temperature, and can quickly undergo a curing reaction under conditions such as heating, light, and moisture, significantly improving the early strength of the cold patch asphalt mixture. Magnesium phosphate gelling material is a new type of quick-setting, high-strength inorganic gelling material with the advantages of good heat resistance, good durability, and fast low-temperature curing; the hydration reaction of magnesium phosphate gelling material is essentially an acid-base neutralization exothermic reaction, and the generated hydration products will connect to form a gel, and finally form a crystal structure network with MgO particles as the skeleton and phosphate crystal hydration products as the binder, becoming a hardened structure, so that the hardened body of magnesium phosphate has very high mechanical properties; in addition, magnesium phosphate gelling material will absorb a certain amount of water during the curing process, which is conducive to the rapid removal of water, and the released heat will also promote the curing of emulsified asphalt. Therefore, magnesium phosphate cementitious materials, waterborne epoxy resin and latent curing agent can form a fast and reasonable curing system, which can significantly improve the modulus and strength of cold patch asphalt mixture, thereby improving the durability and stability of pavement repair.

[0044] The magnesium phosphate cementitious material prepared by the invention can react with water rapidly at room temperature, release a large amount of heat and harden rapidly, and can significantly improve the modulus, early strength and durability of the cold patch asphalt mixture.

[0045] When the latent curing agent prepared by the present invention comes into contact with water, a chemical hydrolysis reaction will occur, activating the amine groups in the curing agent. These amine groups, as curing catalysts for water-based epoxy resins, undergo a ring-opening reaction with the epoxy groups in the water-based epoxy resins to form a three-dimensional network structure. This curing reaction not only rapidly increases the cohesion of the cold-patch asphalt mixture, but also improves the adhesion of the cold-patch asphalt mixture to the road surface. In this way, the latent curing agent ensures that the cold-patch asphalt mixture can harden quickly in the presence of water, while improving the mechanical properties and durability, and can achieve effective road repair even in wet, rainy, snowy, and cold environments.

[0046] The latent curing high-strength and high-modulus cold patch asphalt mixture and the preparation method thereof of the present invention have the following beneficial effects:

[0047] (1) The present invention forms a rapid and reasonable curing system through magnesium phosphate cementitious material, water-based epoxy resin and latent curing agent, which can improve the modulus and strength of cold patch asphalt mixture in harsh environments such as high humidity, rain, snow and cold.

[0048] (2) The cold patch asphalt mixture prepared by the present invention uses a latent curing agent with a unique formula and has excellent environmental adaptability. Especially in harsh environments with high humidity, rain, snow, and cold, the cold patch asphalt mixture can react quickly with moisture to accelerate the curing process and ensure the repair effect.

[0049] (3) The magnesium phosphate cementitious material prepared by the present invention has the characteristics of rapid coagulation and hardening, can react with water rapidly at room temperature, release a large amount of heat and harden rapidly, and can reach a very high early strength in a very short time, which is conducive to the rapid opening of traffic.

[0050] (4) The key components such as the latent curing agent, magnesium phosphate gelling material, composite emulsified asphalt prepared by the present invention can be prefabricated and independently packaged, and the key substances will not undergo chemical reactions before or before construction. This separate storage method can ensure that each component is stably stored at room temperature without the need for special refrigeration, reducing storage costs and complexity. During construction, it is only necessary to mix these prefabricated materials according to the designed ratio to quickly start the curing process. This ready-to-use and mix method not only improves the freshness and construction efficiency of the cold patch asphalt mixture, but also reduces the risk of material waste due to improper storage.

[0051] (5) The cold patch asphalt mixture of the present invention is more suitable for quickly repairing potholes, cracks, damages and other defects on highways or urban roads. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a process flow chart of a preferred embodiment of the latent curing high-strength and high-modulus cold patch asphalt mixture and its preparation method according to the present invention;

[0053] Figure 2 for Figure 1 A physical photo of the composite emulsified asphalt prepared in the embodiment shown;

[0054] Figure 3 for Figure 1 A physical photograph of the magnesium phosphate gel material prepared in the embodiment shown;

[0055] Figure 4 for Figure 1 A real photo of the latent curing agent prepared in the embodiment shown;

[0056] Figure 5 for Figure 1 Actual photograph of the latent curing high-strength and high-modulus cold-patch asphalt mixture prepared in the embodiment shown. DETAILED DESCRIPTION

[0057] In order to further understand the content of the present invention, the present invention will be described in detail below in conjunction with specific embodiments.

[0058] Embodiment 1:

[0059] According to a preferred embodiment of the latent-curing high-strength and high-modulus cold-patch asphalt mixture of the present invention, the mass percentage of each substance in the cold-patch asphalt mixture is 8wt% of composite emulsified asphalt, 3.5wt% of magnesium phosphate cementitious material, 2wt% of latent curing agent, 3.5wt% of water-based epoxy resin, and 83wt% of aggregate.

[0060] The mass percentage of each substance in the composite emulsified asphalt is 56wt% of base asphalt, 13wt% of cationic emulsifier, 3.5wt% of nonionic emulsifier, 1.5wt% of stabilizer, 2wt% of kerosene, and 24wt% of water; the solid content of the composite emulsified asphalt is 82%. The base asphalt is No. 70 base asphalt; the cationic emulsifier is hexadecyl trimethyl ammonium bromide; the nonionic emulsifier is alkylphenol polyoxyethylene ether; and the stabilizer is anhydrous calcium chloride.

[0061] The mass percentage of each substance in the magnesium phosphate gelling material is 46wt% of dead-burned magnesium oxide, 16wt% of diammonium phosphate, 10wt% of fly ash, 10wt% of aluminum oxide, and 18wt% of mineral powder. The particle size distribution of the dead-burned magnesium oxide is between 2-10μm; the particle size distribution of diammonium phosphate is between 30-100μm, and the mass percentage of each particle size of the diammonium phosphate is 35wt% of particle size 75-100μm, 35wt% of particle size 50-75μm, and 30wt% of particle size 30-50μm; the particle size distribution of the fly ash is between 20-100μm, and the particle size distribution of each particle size ... The mass percentage of coal ash is: 35wt% for particle size 75-100μm, 35wt% for particle size 50-75μm, and 30wt% for particle size 20-50μm; the particle size distribution of the alumina is between 0.5-10μm; the particle size distribution of the mineral powder is between 0-75μm, and the mass percentage of each particle size of the mineral powder is: 65wt% for particle size 50-75μm, and 35wt% for particle size 0-50μm.

[0062] The mass percentage of each substance in the latent curing agent is 45wt% of ketimine, 25wt% of polythiol, 15wt% of cardanol, 8wt% of acetone, and 7wt% of polyetheramine. The waterborne epoxy resin is a cationic waterborne epoxy resin, and its solid content is not less than 60%.

[0063] The aggregate includes five particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 12wt%, particle size 9.5-13.2mm accounts for 27wt%, particle size 4.75-9.5mm accounts for 27wt%, particle size 2.36-4.75mm accounts for 22wt%, and particle size 1.18-2.36mm accounts for 12wt%. The aggregate includes limestone.

[0064] like Figure 1 As shown, this embodiment also provides a method for preparing a latent curing high-strength and high-modulus cold-patch asphalt mixture, which is used to prepare the latent curing high-strength and high-modulus cold-patch asphalt mixture, and includes the following steps in order:

[0065] Step 1: Weigh all raw materials according to the designed material ratio;

[0066] Step 2: preparing composite emulsified asphalt, magnesium phosphate gelling material and latent curing agent respectively according to the designed material ratio and process parameters;

[0067] Step 3: Add water-based epoxy resin to the composite emulsified asphalt and mix evenly to obtain emulsified asphalt cold make-up liquid;

[0068] Step 4: Put the aggregates of each particle size into the oven for drying;

[0069] Step 5: Put the dried aggregates of various particle sizes into the mixer for stirring. After stirring for a certain period of time, while keeping the stirring speed unchanged, put the emulsified asphalt cold patch liquid into the mixer and continue stirring. After continuing to stir for a certain period of time, increase the stirring speed, and at the same time put the magnesium phosphate cementitious material into the mixer and continue stirring. After continuing to stir for a certain period of time, while keeping the stirring speed unchanged, put the latent curing agent into the mixer and continue stirring to obtain a latent curing high-strength and high-modulus cold patch asphalt mixture.

[0070] In step 2, the preparation method of the composite emulsified asphalt includes the following steps in order:

[0071] Step (1): weighing and setting aside the raw materials according to the designed material ratio;

[0072] Step (2): placing the matrix asphalt in a container, and then placing the container containing the matrix asphalt in an oil bath and heating it, while performing magnetic stirring until the matrix asphalt is completely melted and kept in a fluid state for standby use, the heating temperature is 88° C., the magnetic stirring speed is 2500 r / min, and the magnetic stirring time is 25 min;

[0073] Step (3): putting the cationic emulsifier and the nonionic emulsifier into another container for compounding, and then adding 85wt% of water for magnetic stirring until they are fully dissolved to form a soap solution, the magnetic stirring speed is 1500r / min, and the magnetic stirring time is 9min; putting the container containing the soap solution into an oil bath pot for heating, and keeping it warm for standby use, the heating temperature is 55°C, and the heating time is 12min; Step (4): putting the stabilizer into another container, and then adding 15wt% of water for magnetic stirring until the stabilizer is fully dissolved in the water to form an aqueous solution for standby use, the magnetic stirring speed is 1500r / min, and the magnetic stirring time is 9min;

[0074] Step (5): placing kerosene into a container containing matrix asphalt and subjecting it to magnetic stirring, the heating temperature is 88° C., the magnetic stirring speed is 2500 r / min, and the magnetic stirring time is 15 min;

[0075] Step (6): Place the soap solution and the aqueous solution into a container containing base asphalt and kerosene for shear stirring at the same time. The heating temperature is 88° C., the shear stirring speed is 1800 r / min, and the shear stirring time is 25 min. Thus, a composite emulsified asphalt is obtained, which is sealed for later use.

[0076] In step 2, the preparation method of the magnesium phosphate gelling material comprises the following steps in order:

[0077] Step (a): weigh and prepare the raw materials according to the designed material ratio;

[0078] Step (b): putting dead-burned magnesium oxide and aluminum oxide into a mixer and stirring them at room temperature, a stirring speed of 150 r / min, and a stirring time of 75 s;

[0079] Step (c): placing fly ash of various particle sizes into a mixer and continuing to stir at room temperature, a stirring speed of 250 r / min, and a stirring time of 120 s;

[0080] Step (d): placing the mineral powders of various particle sizes into a mixer and continuing to stir them at room temperature, a stirring speed of 250 r / min, and a stirring time of 120 s;

[0081] Step (e): placing ammonium dihydrogen phosphate of each particle size into a mixer and continuing to stir at room temperature, a stirring speed of 250 r / min, and a stirring time of 120 s. After the stirring is completed, a mixture of the substances is obtained;

[0082] Step (f): placing the mixture of the substances in an oven for low-temperature drying at 90° C. for 1.5 h. After the drying is completed, a magnesium phosphate gelling material is obtained, which is sealed for later use.

[0083] In step 2, the preparation method of the latent curing agent is to put ketimine, polythiol, cardanol, acetone and polyetheramine into a container according to the designed material ratio and mix them at room temperature to fully blend the substances, and then seal them for later use.

[0084] In step 4, the drying temperature of aggregates of each particle size is 110°C and the drying time is 2.5h.

[0085] In step five, the stirring speed of the aggregates of each particle size after drying is 450 r / min, and the stirring time is 75 s; the emulsified asphalt cold make-up liquid is put into the mixer and continued to be stirred at a speed of 450 r / min and a stirring time of 75 s; the magnesium phosphate cementitious material is put into the mixer and continued to be stirred at a speed of 650 r / min and a stirring time of 120 s; the latent curing agent is put into the mixer and continued to be stirred at a speed of 650 r / min and a stirring time of 120 s.

[0086] In step five, before the latent curing high-strength and high-modulus cold patch asphalt mixture is used in construction, a layer of emulsified asphalt cold patch liquid needs to be applied on the surface to be constructed, and at the same time, the surface of the latent curing high-strength and high-modulus cold patch asphalt mixture needs to be sprayed with water to moisten it. The amount of water sprayed is 0.3% of the latent curing high-strength and high-modulus cold patch asphalt mixture.

[0087] In this embodiment, the prepared composite emulsified asphalt is as follows Figure 2 As shown, the prepared magnesium phosphate gel material is as follows Figure 3 As shown, the prepared latent curing agent is Figure 4 As shown in the figure, the prepared latent curing high-strength and high-modulus cold patch asphalt mixture is as follows Figure 5 shown.

[0088] The latent curing high-strength and high-modulus cold-patch asphalt mixture of this embodiment and its preparation method have the following beneficial effects: (1) A rapid and reasonable curing system is formed by magnesium phosphate cementitious material, water-based epoxy resin and latent curing agent, which can improve the modulus and strength of the cold-patch asphalt mixture in harsh environments such as high humidity, rain, snow and cold. (2) The prepared cold-patch asphalt mixture uses a latent curing agent with a unique formula and has excellent environmental adaptability. Especially in harsh environments such as high humidity, rain, snow and cold, the cold-patch asphalt mixture can react quickly with moisture to accelerate the curing process and ensure the repair effect. (3) The prepared magnesium phosphate cementitious material has the characteristics of rapid coagulation and hardening. It can react quickly with water at room temperature, release a large amount of heat and harden quickly. It can reach a very high early strength in a very short time, which is conducive to the rapid opening of traffic. (4) The prepared key components such as latent curing agent, magnesium phosphate cementitious material, composite emulsified asphalt, etc. can be prefabricated and packaged separately, and the key substances will not undergo chemical reactions before or before construction. This separate storage method can ensure that the components are stably stored at room temperature without the need for special refrigeration. During construction, it is only necessary to mix these prefabricated substances according to the designed ratio to quickly start the curing process.

[0089] Embodiment 2:

[0090] According to another preferred embodiment of the latent curing high-strength and high-modulus cold patch asphalt mixture and its preparation method of the present invention, its material ratio, preparation process, technical principle, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0091] The mass percentages of various substances in the cold patch asphalt mixture are as follows: 7wt% of composite emulsified asphalt, 1.5wt% of magnesium phosphate cementitious material, 0.5wt% of latent curing agent, 5.5wt% of waterborne epoxy resin, and 85.5wt% of aggregate.

[0092] The mass percentage of each substance in the composite emulsified asphalt is 50wt% of base asphalt, 15wt% of cationic emulsifier, 5wt% of nonionic emulsifier, 0.5wt% of stabilizer, 3.5wt% of kerosene, and 26wt% of water; the solid content of the composite emulsified asphalt is 79%. The base asphalt is No. 70 base asphalt; the cationic emulsifier is hexadecyl trimethyl ammonium bromide; the nonionic emulsifier is alkylphenol polyoxyethylene ether; and the stabilizer is anhydrous calcium chloride.

[0093] The mass percentage of each substance in the magnesium phosphate cementitious material is 44wt% of dead-burned magnesium oxide, 18wt% of diammonium phosphate, 11wt% of fly ash, 12wt% of aluminum oxide, and 15wt% of mineral powder. The particle size distribution of the dead-burned magnesium oxide is between 2-10μm; the particle size distribution of diammonium phosphate is between 30-100μm, and the mass percentage of each particle size of the diammonium phosphate is 35wt% of particle size 75-100μm, 35wt% of particle size 50-75μm, and 30wt% of particle size 30-50μm; the particle size distribution of the fly ash is between 20-100μm, and the particle size distribution of each particle size ... The mass percentage of coal ash is: 35wt% for particle size 75-100μm, 35wt% for particle size 50-75μm, and 30wt% for particle size 20-50μm; the particle size distribution of the alumina is between 0.5-10μm; the particle size distribution of the mineral powder is between 0-75μm, and the mass percentage of each particle size of the mineral powder is: 65wt% for particle size 50-75μm, and 35wt% for particle size 0-50μm.

[0094] The mass percentage of each substance in the latent curing agent is 40wt% of ketimine, 20wt% of polythiol, 20wt% of cardanol, 10wt% of acetone, and 10wt% of polyetheramine. The waterborne epoxy resin is a cationic waterborne epoxy resin, and its solid content is not less than 60%.

[0095] The aggregate includes five particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 10wt%, particle size 9.5-13.2mm accounts for 25wt%, particle size 4.75-9.5mm accounts for 25wt%, particle size 2.36-4.75mm accounts for 25wt%, and particle size 1.18-2.36mm accounts for 15wt%. The aggregate includes limestone.

[0096] In step 2, the preparation process parameters of the composite emulsified asphalt are: the heating temperature of the matrix asphalt is 80°C, the magnetic stirring speed is 3000r / min, and the magnetic stirring time is 20min. After the cationic emulsifier and the non-ionic emulsifier are compounded, 80wt% of water is added for magnetic stirring to form a soap solution, the magnetic stirring speed is 2000r / min, and the magnetic stirring time is 8min; the heating temperature of the soap solution is 50°C, and the heating time is 15min. 20wt% of water is added to the stabilizer for magnetic stirring to form an aqueous solution, the magnetic stirring speed is 2000r / min, and the magnetic stirring time is 8min. Put kerosene into a container containing matrix asphalt for magnetic stirring, the heating temperature is 85°C, the magnetic stirring speed is 3000r / min, and the magnetic stirring time is 10min. Put the soap solution and the aqueous solution into a container containing matrix asphalt and kerosene at the same time for shear stirring, the heating temperature is 85°C, the shear stirring speed is 2000r / min, and the shear stirring time is 20min.

[0097] The preparation process parameters of magnesium phosphate cementitious material are as follows: the stirring speed of dead-burned magnesium oxide and aluminum oxide is 100r / min, and the stirring time is 90s; fly ash of various particle sizes is added and continued to be stirred at a stirring speed of 200r / min, and the stirring time is 150s; mineral powder of various particle sizes is added and continued to be stirred at a stirring speed of 200r / min, and the stirring time is 150s; ammonium dihydrogen phosphate of various particle sizes is added and continued to be stirred at a stirring speed of 200r / min, and the stirring time is 150s; the mixture of various substances is placed in an oven for low-temperature drying treatment, the drying temperature is 80°C, and the drying time is 2h.

[0098] In step 4, the drying temperature of aggregates of each particle size is 100°C and the drying time is 3 hours.

[0099] In step 5, the mixing speed of the aggregates of each particle size after drying is 400r / min, and the mixing time is 90s; the emulsified asphalt cold patch liquid is put into the mixer and continued to be stirred at a speed of 400r / min and a stirring time of 90s; the magnesium phosphate cementitious material is put into the mixer and continued to be stirred at a speed of 500r / min and a stirring time of 150s; the latent curing agent is put into the mixer and continued to be stirred at a speed of 500r / min and a stirring time of 150s. During construction, it is necessary to spray water on the surface of the latent curing high-strength and high-modulus cold patch asphalt mixture to moisten it, and the amount of water sprayed is 0.1% of the latent curing high-strength and high-modulus cold patch asphalt mixture.

[0100] Embodiment three:

[0101] According to another preferred embodiment of the latent curing high-strength and high-modulus cold patch asphalt mixture and its preparation method of the present invention, its material ratio, preparation process, technical principle, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0102] The mass percentages of various substances in the cold patch asphalt mixture are: 10wt% of composite emulsified asphalt, 5.5wt% of magnesium phosphate gelling material, 3.5wt% of latent curing agent, 1.5wt% of waterborne epoxy resin, and 79.5wt% of aggregate.

[0103] The mass percentage of each substance in the composite emulsified asphalt is 60wt% of base asphalt, 10wt% of cationic emulsifier, 2wt% of nonionic emulsifier, 2.5wt% of stabilizer, 0.5wt% of kerosene, and 25wt% of water; the solid content of the composite emulsified asphalt is 81%. The base asphalt is No. 70 base asphalt; the cationic emulsifier is hexadecyl trimethyl ammonium bromide; the nonionic emulsifier is alkylphenol polyoxyethylene ether; and the stabilizer is anhydrous calcium chloride.

[0104] The mass percentage of each substance in the magnesium phosphate gelling material is 52wt% of dead-burned magnesium oxide, 14wt% of diammonium phosphate, 8wt% of fly ash, 8wt% of aluminum oxide, and 18wt% of mineral powder. The particle size distribution of the dead-burned magnesium oxide is between 2-10μm; the particle size distribution of the diammonium phosphate is between 30-100μm, and the mass percentage of each particle size of the diammonium phosphate is 35wt% of the particle size of 75-100μm, 35wt% of the particle size of 50-75μm, and 30wt% of the particle size of 30-50μm; the particle size distribution of the fly ash is between 20-100μm, and the particle size distribution of each particle size ... The mass percentage of coal ash is: 35wt% for particle size 75-100μm, 35wt% for particle size 50-75μm, and 30wt% for particle size 20-50μm; the particle size distribution of the alumina is between 0.5-10μm; the particle size distribution of the mineral powder is between 0-75μm, and the mass percentage of each particle size of the mineral powder is: 65wt% for particle size 50-75μm, and 35wt% for particle size 0-50μm.

[0105] The mass percentage of each substance in the latent curing agent is 50wt% of ketimine, 30wt% of polythiol, 10wt% of cardanol, 5wt% of acetone, and 5wt% of polyetheramine. The waterborne epoxy resin is a cationic waterborne epoxy resin, and its solid content is not less than 60%.

[0106] The aggregate includes five particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 15wt%, particle size 9.5-13.2mm accounts for 27wt%, particle size 4.75-9.5mm accounts for 28wt%, particle size 2.36-4.75mm accounts for 20wt%, and particle size 1.18-2.36mm accounts for 10wt%. The aggregate includes limestone.

[0107] In step 2, the preparation process parameters of the composite emulsified asphalt are: the heating temperature of the base asphalt is 90°C, the magnetic stirring speed is 2000r / min, and the magnetic stirring time is 30min. After the cationic emulsifier and the non-ionic emulsifier are compounded, 90wt% of water is added for magnetic stirring to form a soap solution, the magnetic stirring speed is 1000r / min, and the magnetic stirring time is 10min; the heating temperature of the soap solution is 60°C, and the heating time is 10min. 10wt% of water is added to the stabilizer for magnetic stirring to form an aqueous solution, the magnetic stirring speed is 1000r / min, and the magnetic stirring time is 10min. Put kerosene into a container containing base asphalt for magnetic stirring, the heating temperature is 90°C, the magnetic stirring speed is 2000r / min, and the magnetic stirring time is 20min. The soap solution and the aqueous solution are simultaneously placed in a container containing matrix asphalt and kerosene for shear stirring. The heating temperature is 90°C, the shear stirring speed is 1500r / min, and the shear stirring time is 30min.

[0108] The preparation process parameters of magnesium phosphate cementitious material are as follows: the stirring speed of dead-burned magnesium oxide and aluminum oxide is 200r / min, and the stirring time is 60s; fly ash of various particle sizes is added and continued to be stirred at a stirring speed of 300r / min, and the stirring time is 90s; mineral powder of various particle sizes is added and continued to be stirred at a stirring speed of 300r / min, and the stirring time is 90s; ammonium dihydrogen phosphate of various particle sizes is added and continued to be stirred at a stirring speed of 300r / min, and the stirring time is 90s; the mixture of various substances is placed in an oven for low-temperature drying treatment, the drying temperature is 100°C, and the drying time is 1h.

[0109] In step 4, the drying temperature of aggregates of each particle size is 120°C and the drying time is 2h.

[0110] In step 5, the mixing speed of the aggregates of each size after drying is 500r / min, and the mixing time is 60s; the emulsified asphalt cold patch liquid is put into the mixer and continued to be stirred at a speed of 500r / min and a stirring time of 60s; the magnesium phosphate cementitious material is put into the mixer and continued to be stirred at a speed of 800r / min and a stirring time of 90s; the latent curing agent is put into the mixer and continued to be stirred at a speed of 800r / min and a stirring time of 90s. During construction, water is sprayed on the surface of the latent curing high-strength and high-modulus cold patch asphalt mixture to moisten it, and the amount of water sprayed is 0.5% of the latent curing high-strength and high-modulus cold patch asphalt mixture.

[0111] Embodiment 4:

[0112] According to another preferred embodiment of the latent curing high-strength and high-modulus cold patch asphalt mixture and its preparation method of the present invention, its material ratio, preparation process, technical principle, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0113] The mass percentages of various substances in the cold patch asphalt mixture are: 7.5wt% of composite emulsified asphalt, 3wt% of magnesium phosphate gelling material, 3wt% of latent curing agent, 4.5wt% of waterborne epoxy resin, and 82wt% of aggregate.

[0114] The mass percentage of each substance in the composite emulsified asphalt is 54wt% of base asphalt, 14wt% of cationic emulsifier, 4wt% of nonionic emulsifier, 2wt% of stabilizer, 3wt% of kerosene, and 23wt% of water; the solid content of the composite emulsified asphalt is 82%. The base asphalt is No. 90 base asphalt; the cationic emulsifier is octadecyl trimethyl ammonium chloride; the nonionic emulsifier is fatty acid glyceride; and the stabilizer is magnesium sulfate.

[0115] The mass percentage of each substance in the magnesium phosphate gelling material is 45wt% of dead-burned magnesium oxide, 17wt% of diammonium phosphate, 9wt% of fly ash, 9wt% of aluminum oxide, and 20wt% of mineral powder. The particle size distribution of the dead-burned magnesium oxide is between 2-10μm; the particle size distribution of diammonium phosphate is between 30-100μm, and the mass percentage of each particle size of the diammonium phosphate is 35wt% of particle size 75-100μm, 35wt% of particle size 50-75μm, and 30wt% of particle size 30-50μm; the particle size distribution of the fly ash is between 20-100μm, and the particle size distribution of each particle size ... The mass percentage of coal ash is: 35wt% for particle size 75-100μm, 35wt% for particle size 50-75μm, and 30wt% for particle size 20-50μm; the particle size distribution of the alumina is between 0.5-10μm; the particle size distribution of the mineral powder is between 0-75μm, and the mass percentage of each particle size of the mineral powder is: 65wt% for particle size 50-75μm, and 35wt% for particle size 0-50μm.

[0116] The mass percentage of each substance in the latent curing agent is 43wt% of ketimine, 22wt% of polythiol, 18wt% of cardanol, 9wt% of acetone, and 8wt% of polyetheramine. The waterborne epoxy resin is a non-ionic waterborne epoxy resin, and its solid content is not less than 60%.

[0117] The aggregate includes five particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 11wt%, particle size 9.5-13.2mm accounts for 26wt%, particle size 4.75-9.5mm accounts for 26wt%, particle size 2.36-4.75mm accounts for 23wt%, and particle size 1.18-2.36mm accounts for 14wt%. The aggregate includes basalt.

[0118] In step 2, the preparation process parameters of the composite emulsified asphalt are: the heating temperature of the base asphalt is 86°C, the magnetic stirring speed is 2800r / min, and the magnetic stirring time is 22min. After the cationic emulsifier and the non-ionic emulsifier are compounded, 83wt% of water is added for magnetic stirring to form a soap solution, the magnetic stirring speed is 1800r / min, and the magnetic stirring time is 8.5min; the heating temperature of the soap solution is 53°C, and the heating time is 13min. 17wt% of water is added to the stabilizer for magnetic stirring to form an aqueous solution, the magnetic stirring speed is 1800r / min, and the magnetic stirring time is 8.5min. Put kerosene into a container containing base asphalt for magnetic stirring, the heating temperature is 83°C, the magnetic stirring speed is 2800r / min, and the magnetic stirring time is 13min. The soap solution and the aqueous solution are simultaneously placed in a container containing matrix asphalt and kerosene for shear stirring. The heating temperature is 83°C, the shear stirring speed is 1900 r / min, and the shear stirring time is 22 min.

[0119] The preparation process parameters of magnesium phosphate cementitious material are as follows: the stirring speed of dead-burned magnesium oxide and aluminum oxide is 120r / min, and the stirring time is 85s; fly ash of various particle sizes is added and continued to be stirred, and the stirring speed is 220r / min, and the stirring time is 135s; mineral powder of various particle sizes is added and continued to be stirred, and the stirring speed is 220r / min, and the stirring time is 135s; ammonium dihydrogen phosphate of various particle sizes is added and continued to be stirred, and the stirring speed is 220r / min, and the stirring time is 135s; the mixture of various substances is put into an oven for low-temperature drying treatment, the drying temperature is 85°C, and the drying time is 1.8h.

[0120] In step 4, the drying temperature of aggregates of each particle size is 105°C and the drying time is 2.8h.

[0121] In step 5, the mixing speed of the aggregates of each size after drying is 420r / min, and the mixing time is 85s; the emulsified asphalt cold patch liquid is put into the mixer and continued to be stirred at a speed of 420r / min and a stirring time of 85s; the magnesium phosphate cementitious material is put into the mixer and continued to be stirred at a speed of 600r / min and a stirring time of 135s; the latent curing agent is put into the mixer and continued to be stirred at a speed of 600r / min and a stirring time of 135s. During construction, the surface of the latent curing high-strength and high-modulus cold patch asphalt mixture is sprayed with water to moisten it, and the amount of water sprayed is 0.2% of the latent curing high-strength and high-modulus cold patch asphalt mixture.

[0122] Embodiment five:

[0123] According to another preferred embodiment of the latent curing high-strength and high-modulus cold patch asphalt mixture and its preparation method of the present invention, its material ratio, preparation process, technical principle, beneficial effects, etc. are basically the same as those of the first embodiment, except that:

[0124] The mass percentages of various substances in the cold patch asphalt mixture are: 9.5wt% of composite emulsified asphalt, 4.5wt% of magnesium phosphate cementitious material, 1.5wt% of latent curing agent, 2.5wt% of waterborne epoxy resin, and 82wt% of aggregate.

[0125] The mass percentage of each substance in the composite emulsified asphalt is 58wt% of base asphalt, 12wt% of cationic emulsifier, 3wt% of nonionic emulsifier, 1wt% of stabilizer, 1wt% of kerosene, and 25wt% of water; the solid content of the composite emulsified asphalt is 79%. The base asphalt is No. 90 base asphalt; the cationic emulsifier is behenyl trimethyl ammonium chloride; the nonionic emulsifier is polyoxyethylene sorbitol ester; and the stabilizer is hydroxyethyl cellulose.

[0126] The mass percentage of each substance in the magnesium phosphate gelling material is 50wt% of dead-burned magnesium oxide, 15wt% of diammonium phosphate, 10wt% of fly ash, 10wt% of aluminum oxide, and 15wt% of mineral powder. The particle size distribution of the dead-burned magnesium oxide is between 2-10μm; the particle size distribution of diammonium phosphate is between 30-100μm, and the mass percentage of each particle size of the diammonium phosphate is 35wt% of particle size 75-100μm, 35wt% of particle size 50-75μm, and 30wt% of particle size 30-50μm; the particle size distribution of the fly ash is between 20-100μm, and the particle size distribution of each particle size ... The mass percentage of coal ash is: 35wt% for particle size 75-100μm, 35wt% for particle size 50-75μm, and 30wt% for particle size 20-50μm; the particle size distribution of the alumina is between 0.5-10μm; the particle size distribution of the mineral powder is between 0-75μm, and the mass percentage of each particle size of the mineral powder is: 65wt% for particle size 50-75μm, and 35wt% for particle size 0-50μm.

[0127] The mass percentage of each substance in the latent curing agent is 48wt% of ketimine, 28wt% of polythiol, 12wt% of cardanol, 6wt% of acetone, and 6wt% of polyetheramine. The waterborne epoxy resin is a non-ionic waterborne epoxy resin, and its solid content is not less than 60%.

[0128] The aggregate includes five particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 13wt%, particle size 9.5-13.2mm accounts for 28wt%, particle size 4.75-9.5mm accounts for 27wt%, particle size 2.36-4.75mm accounts for 21wt%, and particle size 1.18-2.36mm accounts for 11wt%. The aggregate includes basalt.

[0129] In step 2, the preparation process parameters of the composite emulsified asphalt are: the heating temperature of the base asphalt is 89°C, the magnetic stirring speed is 2200r / min, and the magnetic stirring time is 28min. After the cationic emulsifier and the non-ionic emulsifier are compounded, 88wt% of water is added for magnetic stirring to form a soap solution, the magnetic stirring speed is 1200r / min, and the magnetic stirring time is 9.5min; the heating temperature of the soap solution is 58°C, and the heating time is 11min. 12wt% of water is added to the stabilizer for magnetic stirring to form an aqueous solution, the magnetic stirring speed is 1200r / min, and the magnetic stirring time is 9.5min. Put kerosene into a container containing base asphalt for magnetic stirring, the heating temperature is 89°C, the magnetic stirring speed is 2200r / min, and the magnetic stirring time is 18min. The soap solution and the aqueous solution are simultaneously placed in a container containing matrix asphalt and kerosene for shear stirring. The heating temperature is 89° C., the shear stirring speed is 1700 r / min, and the shear stirring time is 28 min.

[0130] The preparation process parameters of magnesium phosphate cementitious material are as follows: the stirring speed of dead-burned magnesium oxide and aluminum oxide is 180r / min, and the stirring time is 70s; fly ash of various particle sizes is added and continued to be stirred, and the stirring speed is 280r / min, and the stirring time is 110s; mineral powder of various particle sizes is added and continued to be stirred, and the stirring speed is 280r / min, and the stirring time is 110s; ammonium dihydrogen phosphate of various particle sizes is added and continued to be stirred, and the stirring speed is 280r / min, and the stirring time is 110s; the mixture of various substances is placed in an oven for low-temperature drying treatment, the drying temperature is 95°C, and the drying time is 1.2h.

[0131] In step 4, the drying temperature of aggregates of each particle size is 115°C and the drying time is 2.2h.

[0132] In step 5, the mixing speed of the aggregates of each particle size after drying is 480r / min, and the mixing time is 70s; the emulsified asphalt cold patch liquid is put into the mixer and continued to be stirred at a speed of 480r / min and a stirring time of 70s; the magnesium phosphate cementitious material is put into the mixer and continued to be stirred at a speed of 750r / min and a stirring time of 110s; the latent curing agent is put into the mixer and continued to be stirred at a speed of 750r / min and a stirring time of 110s. During construction, the surface of the latent curing high-strength and high-modulus cold patch asphalt mixture is sprayed with water to moisten it, and the amount of water sprayed is 0.4% of the latent curing high-strength and high-modulus cold patch asphalt mixture.

[0133] The cold patch asphalt mixtures prepared in the above five embodiments were subjected to the immersion Marshall test, freeze-thaw splitting test, rutting test, beam low-temperature bending test, cohesion test, curing time measurement, etc. Each test must comply with the corresponding test operation specifications, such as the "Test Procedures for Asphalt and Asphalt Mixtures for Highway Engineering" (JTG E20-2011). The test equipment, test environment, test conditions, sample shape and size used in each test are the same.

[0134] The immersion Marshall test and freeze-thaw splitting test are used to test the water damage resistance of cold-patch asphalt mixture, which are characterized by the residual stability after immersion and the freeze-thaw splitting strength ratio respectively; the rutting test (60℃, 0.7MPa) is used to test the high temperature performance of cold-patch asphalt mixture, which is characterized by the dynamic stability; the beam low temperature bending test (-10℃) is used to test the low temperature resistance of cold-patch asphalt mixture, which is characterized by the flexural tensile strength, ultimate flexural tensile strain, and flexural stiffness modulus; the cohesion test is used to test the early strength of cold-patch asphalt mixture, which is characterized by the damage rate; the curing speed of cold-patch asphalt mixture is characterized by measuring the curing time. The test results are shown in Table 1.

[0135] Table 1 Performance test results of cold patch asphalt mixture

[0136]

[0137] It can be seen from the test results that the cold-patch asphalt mixture prepared in the above embodiment has the characteristics of high modulus, fast curing speed, high early strength, good stability, etc. The good stability is reflected in the strong resistance to water damage, good high temperature performance, strong resistance to low temperature, etc. The comprehensive performance can meet the performance requirements of hot-mix asphalt mixture.

[0138] The aggregates used in the above embodiments, the various substances used to prepare magnesium phosphate cementitious materials, matrix asphalt and other substances were purchased from Beijing Municipal Road and Bridge Building Materials Group Co., Ltd., and the various substances used to prepare composite emulsified asphalt, the various substances used to prepare latent curing agents, water-based epoxy resins and other substances were purchased from Aladdin Reagent Co., Ltd.

[0139] Special note: The technical solution of the present invention involves many parameters, and the synergistic effects between the various parameters need to be comprehensively considered to obtain the beneficial effects and significant progress of the present invention. Moreover, the value ranges of the various parameters in the technical solution are obtained after a large number of experiments. For each parameter and the combination of each parameter, the inventor has recorded a large amount of experimental data. Due to space limitations, the specific experimental data will not be disclosed here.

[0140] It is not difficult for those skilled in the art to understand that the latent curing high-strength and high-modulus cold patch asphalt mixture and its preparation method of the present invention include any combination of the invention content and specific implementation methods of the above-mentioned invention specification and the various parts shown in the drawings. Due to the limited space and to make the specification concise, the various schemes composed of these combinations are not described one by one. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A latent curing high-strength and high-modulus cold-patch asphalt mixture, characterized in that: The mass percentages of various substances in the cold patch asphalt mixture are: 7-10wt% of composite emulsified asphalt, 1.5-5.5wt% of magnesium phosphate cementitious material, 0.5-3.5wt% of latent curing agent, 1.5-5.5wt% of waterborne epoxy resin, and 78-88wt% of aggregate, and the sum of the contents of various substances is 100wt%.

2. The latent curing high-strength and high-modulus cold patch asphalt mixture according to claim 1 is characterized in that: The mass percentages of the various substances in the composite emulsified asphalt are: 50-60wt% of base asphalt, 10-15wt% of cationic emulsifier, 2-5wt% of non-ionic emulsifier, 0.5-2.5wt% of stabilizer, 0.5-3.5wt% of kerosene, and 22-26wt% of water, and the sum of the contents of the various substances is 100wt%; the solid content of the composite emulsified asphalt is not less than 75%.

3. The latent curing high-strength and high-modulus cold patch asphalt mixture according to claim 2 is characterized in that: The base asphalt is No. 70 base asphalt and / or No. 90 base asphalt; the cationic emulsifier includes any one or more of cetyltrimethylammonium bromide, octadecyltrimethylammonium chloride, and docosyltrimethylammonium chloride; the nonionic emulsifier includes any one or more of alkylphenol polyoxyethylene ether, fatty acid glyceride, and polyoxyethylene sorbitan ester; the stabilizer includes any one or more of anhydrous calcium chloride, magnesium sulfate, hydroxyethyl cellulose, and carboxymethyl cellulose.

4. The latent curing high-strength and high-modulus cold patch asphalt mixture according to claim 3 is characterized in that: The mass percentage of each substance in the magnesium phosphate gelling material is 44-52wt% of dead-burned magnesium oxide, 14-18wt% of diammonium phosphate, 8-12wt% of fly ash, 8-12wt% of aluminum oxide, and 15-20wt% of mineral powder, and the sum of the contents of each substance is 100wt%.

5. The latent curing high-strength and high-modulus cold patch asphalt mixture according to claim 4 is characterized in that: The particle size distribution of the dead-burned magnesium oxide is between 2-10 μm; the particle size distribution of the ammonium dihydrogen phosphate is between 30-100 μm, wherein the mass percentage of each particle size in the ammonium dihydrogen phosphate is 35wt% for a particle size of 75-100 μm, 35wt% for a particle size of 50-75 μm, and 30wt% for a particle size of 30-50 μm; the particle size distribution of the fly ash is between 20-100 μm, wherein each particle size in the fly ash accounts for 35wt% of the mass percentage of the fly ash. The mass percentage of coal ash is: 35wt% for particle size 75-100μm, 35wt% for particle size 50-75μm, and 30wt% for particle size 20-50μm; the particle size distribution of the alumina is between 0.5-10μm; the particle size distribution of the mineral powder is between 0-75μm, and the mass percentage of each particle size of the mineral powder is: 65wt% for particle size 50-75μm, and 35wt% for particle size 0-50μm.

6. The latent curing high-strength and high-modulus cold patch asphalt mixture according to claim 5, characterized in that: The mass percentage of each substance in the latent curing agent is 40-50wt% of ketimine, 20-30wt% of polythiol, 10-20wt% of cardanol, 5-10wt% of acetone, and 5-10wt% of polyetheramine, and the sum of the contents of each substance is 100wt%.

7. The latent curing high-strength and high-modulus cold patch asphalt mixture according to claim 6 is characterized in that: The waterborne epoxy resin is a cationic waterborne epoxy resin and / or a nonionic waterborne epoxy resin, and the solid content of the waterborne epoxy resin is not less than 60%.

8. The latent curing high-strength and high-modulus cold patch asphalt mixture according to claim 7, characterized in that: The aggregate includes five particle sizes, and the mass percentage of each particle size in the aggregate is: particle size 13.2-16mm accounts for 10-15wt%, particle size 9.5-13.2mm accounts for 25-30wt%, particle size 4.75-9.5mm accounts for 25-30wt%, particle size 2.36-4.75mm accounts for 20-25wt%, and particle size 1.18-2.36mm accounts for 10-15wt%. The aggregate includes any one or more of limestone, basalt, granite, and diabase.

9. A method for preparing a latent curing high-strength and high-modulus cold-patch asphalt mixture, characterized in that: The method for preparing the latent curing high-strength and high-modulus cold patch asphalt mixture according to any one of claims 1 to 8 comprises the following steps in chronological order: Step 1: Weigh all raw materials according to the designed material ratio; Step 2: preparing composite emulsified asphalt, magnesium phosphate gelling material and latent curing agent respectively according to the designed material ratio and process parameters; Step 3: Add water-based epoxy resin to the composite emulsified asphalt and mix evenly to obtain emulsified asphalt cold make-up liquid; Step 4: Put the aggregates of each particle size into the oven for drying; Step 5: Put the dried aggregates of various particle sizes into the mixer for stirring. After stirring for a certain period of time, while keeping the stirring speed unchanged, put the emulsified asphalt cold patch liquid into the mixer and continue stirring. After continuing to stir for a certain period of time, increase the stirring speed, and at the same time put the magnesium phosphate cementitious material into the mixer and continue stirring. After continuing to stir for a certain period of time, while keeping the stirring speed unchanged, put the latent curing agent into the mixer and continue stirring to obtain a latent curing high-strength and high-modulus cold patch asphalt mixture.

10. The method for preparing the latent curing high-strength and high-modulus cold-patch asphalt mixture according to claim 10, characterized in that: In step 2, the preparation method of the composite emulsified asphalt includes the following steps in order: Step (1): weighing and setting aside the raw materials according to the designed material ratio; Step (2): placing the matrix asphalt in a container, and then placing the container containing the matrix asphalt in an oil bath and heating it, while performing magnetic stirring until the matrix asphalt is completely melted and kept in a fluid state for standby use, the heating temperature is 85-90° C., the magnetic stirring speed is 2000-3000 r / min, and the magnetic stirring time is 20-30 min; Step (3): putting the cationic emulsifier and the nonionic emulsifier into another container for compounding, and then adding 80-90wt% of water for magnetic stirring until they are fully dissolved to form a soap solution, the magnetic stirring speed is 1000-2000r / min, and the magnetic stirring time is 8-10min; putting the container containing the soap solution into an oil bath pot for heating, and keeping it warm for standby use, the heating temperature is 50-60°C, and the heating time is 10-15min; Step (4): placing the stabilizer in another container, adding 10-20wt% of water and performing magnetic stirring until the stabilizer is fully dissolved in the water to form an aqueous solution for standby use, the magnetic stirring speed is 1000-2000r / min, and the magnetic stirring time is 8-10min; Step (5): placing kerosene in a container containing matrix asphalt and performing magnetic stirring, the heating temperature is 85-90°C, the magnetic stirring speed is 2000-3000r / min, and the magnetic stirring time is 10-20min; Step (6): placing the soap solution and the aqueous solution into a container containing base asphalt and kerosene for shear stirring at a heating temperature of 85-90° C., a shear stirring speed of 1500-2000 r / min, and a shear stirring time of 20-30 min, thereby obtaining a composite emulsified asphalt, which is then sealed for later use; In step 2, the preparation method of the magnesium phosphate gelling material comprises the following steps in order: Step (a): weigh and prepare the raw materials according to the designed material ratio; Step (b): putting dead-burned magnesium oxide and aluminum oxide into a mixer and stirring them at room temperature, a stirring speed of 100-200 r / min, and a stirring time of 60-90 s; Step (c): placing fly ash of various particle sizes into a mixer and continuing to stir at room temperature, a stirring speed of 200-300 r / min, and a stirring time of 90-150 s; Step (d): placing the mineral powders of various particle sizes into a mixer and continuing to stir them at room temperature, a stirring speed of 200-300 r / min, and a stirring time of 90-150 s; Step (e): placing diammonium hydrogen phosphate of various particle sizes into a mixer and continuing to stir at room temperature, a stirring speed of 200-300 r / min, and a stirring time of 90-150 s. After the stirring is completed, a mixture of the substances is obtained; Step (f): placing the mixture of the substances in an oven for low-temperature drying at a temperature of 80-100° C. for a drying time of 1-2 h. After the drying is completed, a magnesium phosphate gelling material is obtained, which is sealed for later use; In step 2, the preparation method of the latent curing agent is to put ketimine, polythiol, cardanol, acetone and polyetheramine into a container according to the designed material ratio and mix them at room temperature to fully blend the materials, and then seal them for later use; In step 4, the drying temperature of aggregates of each size range is 100-120°C, and the drying time is 2-3h; In step 5, the stirring speed of the aggregates of each particle size after drying is 400-500r / min, and the stirring time is 60-90s; Put the emulsified asphalt cold make-up liquid into the mixer and continue to stir at a speed of 400-500r / min for 60-90s; put the magnesium phosphate gelling material into the mixer and continue to stir at a speed of 500-800r / min for 90-150s; put the latent curing agent into the mixer and continue to stir at a speed of 500-800r / min for 90-150s; In step five, before the latent curing high-strength and high-modulus cold patch asphalt mixture is used in construction, a layer of emulsified asphalt cold patch liquid needs to be applied on the surface to be constructed, and at the same time, the surface of the latent curing high-strength and high-modulus cold patch asphalt mixture needs to be sprayed with water to moisten it. The amount of water sprayed is 0.1-0.5% of the latent curing high-strength and high-modulus cold patch asphalt mixture.

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