High-performance solvent type asphalt cold patch material and preparation method thereof

Abstract

According to the high-performance solvent type asphalt cold patch material and the preparation method thereof, the performance of the cold patch material is remarkably improved by optimizing a formula, enhancing the water stability and the bonding performance, preventing aggregate and asphalt from being stripped by using slaked lime or a liquid amine anti-stripping agent, delaying ultraviolet aging by adding carbon black or an antioxidant and the like. Performance tests show that the cold patch material has excellent low-temperature cohesiveness, water damage resistance and aging resistance. Meanwhile, by reasonably selecting the raw materials and optimizing the process, the cost is reduced, and the material is suitable for large-scale road maintenance. In different application scenes, such as pluvial regions, low-temperature regions, shallow repair and deep repair, targeted design can be performed according to the performance characteristics of the cold repair material, and the cold repair material has a good application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of road engineering materials, and particularly relates to a high-performance solvent-based asphalt cold patch material and a preparation method thereof. Background Art

[0002] With the continuous development of transportation infrastructure, the maintenance and repair of roads have become increasingly important. As a commonly used road repair material, asphalt cold patch material has been widely used in the field of road maintenance due to its advantages such as no need for heating and being able to be repaired at any time. However, traditional solvent-based asphalt cold patch materials have many deficiencies in performance.

[0003] Patent document CN202211008343.3 discloses an asphalt cold patch material and a preparation method thereof. The asphalt cold patch material is made from the following raw materials: waste aggregate containing asphalt, stone materials, and a polymer asphalt cold patch liquid. The above raw materials are prepared according to the following weight ratio: 15 - 60 parts of waste aggregate containing asphalt, 30 - 80 parts of stone materials, and 15 - 40 parts of polymer asphalt cold patch liquid.

[0004] Patent document CN201910584136.4 discloses a moisture-curing reaction type asphalt pavement cold patch material and a preparation method thereof. The moisture-curing reaction type asphalt pavement cold patch material includes the following raw materials: asphalt, mineral aggregate, mineral powder, diluent, moisture-curing prepolymer, tackifier, and modifier. The mass ratio of each raw material is: asphalt: mineral aggregate: mineral powder = (4 - 6): 100: (0 - 3); asphalt: diluent = (70 - 90): (30 - 10); diluted asphalt: moisture-curing prepolymer: modifier: tackifier = 100: (10 - 50): (0 - 10): (0 - 10); wherein, the diluted asphalt is a mixture of asphalt + diluent + modifier + tackifier; wherein, the mineral aggregate is RAP recycled material or new material from road milling.

[0005] Patent document CN201910049685.1 discloses an asphalt road cold patch material. By weight, the raw materials include the following components: 50 - 70 parts of matrix asphalt; 1 - 4 parts of release agent; 4 - 6 parts of emulsifier; 1 - 3 parts of natural rubber latex; 15 - 25 parts of aggregate. The present invention has the following advantages: The release agent is an organic solvent, which can reduce the viscosity of asphalt, enabling the asphalt mixture to be mixed at a lower temperature and having good workability during construction. With the repeated loading of compaction machinery and vehicles, the organic solvent volatilizes, and the strength of the cold patch material gradually increases to form a formed strength. The emulsifier has good emulsifying and dispersing effects, which can improve the workability of the cold patch material during construction. Natural rubber latex can better improve the adhesion and has good low-temperature crack resistance. It is evenly distributed in the system under the dispersion effect of the emulsifier, improving the adhesion of the system after forming and not being prone to embrittlement under low-temperature conditions.

[0006] In terms of bond performance, for existing cold patch materials, their bonding strength significantly decreases in low-temperature environments, resulting in problems such as peeling and loosening of the repaired road surface during the low-temperature season, which affects the service life of the road and driving safety. When facing rain erosion, some cold patch materials have poor water damage resistance, and water easily penetrates into the joint between the cold patch material and the original road surface, causing the separation of aggregates and asphalt, thereby reducing the overall strength of the road surface. Moreover, when exposed to the natural environment for a long time, the asphalt in the cold patch material will be affected by factors such as ultraviolet rays and oxygen and age, causing the performance of the cold patch material to gradually deteriorate and shortening the effective service life of the repaired road surface.

[0007] In terms of environmental protection and cost, the solvents (such as diesel) used in traditional solvent-based asphalt cold patch materials will produce a large amount of volatile organic compounds (VOCs) during the volatilization process, causing environmental pollution. And, the cost of some raw materials with better performance is relatively high, which limits the application of cold patch materials in large-scale road maintenance.

[0008] Therefore, it is of great practical significance to develop a solvent-based asphalt cold patch material with high performance, environmental protection and controllable cost and its preparation method. Summary of the Invention

[0009] The purpose of the present invention is to provide a high-performance solvent-based asphalt cold patch material and its preparation method, aiming to solve the problems of poor bond performance, weak water damage resistance, easy aging, insufficient environmental protection and relatively high cost of traditional solvent-based asphalt cold patch materials, so as to meet the requirements of modern road maintenance for high performance, environmental protection and economy of materials.

[0010] To achieve the above purpose, on the one hand, the present invention provides a high-performance solvent-based asphalt cold patch material, which, by mass percentage, includes the following components: 3%-6% of asphalt binder, the asphalt binder is composed of asphalt material and solvent, wherein the solvent accounts for 20%-30% of the asphalt binder; 45%-55% of coarse aggregate, with a particle size of 4.75-13.2 mm; 35%-40% of fine aggregate, with a particle size of 0.075-4.75 mm; 3%-6% of mineral powder, with a particle size of <0.075 mm, and the mineral powder contains 40%-60% of cement; 1%-2% of tackifier; 0.5%-1% of anti-stripping agent; 0.2%-0.5% of anti-aging agent; 0.1%-0.3% of curing regulator.

[0011] Further, the solvent in the solvent-based asphalt is one or more of kerosene, diesel, bio-oil and vegetable oil; the coarse aggregate is composed of basalt and limestone, providing compressive strength and skeleton support; the fine aggregate is composed of manufactured sand and stone chips, filling voids and enhancing density;

[0012] Mineral powder is a mixture of limestone powder and cement. In high-performance solvent-based asphalt cold patch material, adding 40%-60% cement to the mineral powder can enhance water stability, improve bonding performance, and enhance overall strength, making the cold patch material better and the repair effect better. Cement has good water absorption and water hardness. In a humid environment, cement can react with water to form hydration products, fill the pores inside the cold patch material, and prevent water from invading. Cement can also form a more stable structure with mineral powder, asphalt, etc., enhance the ability of the cold patch material to resist water damage, avoid problems such as aggregate and asphalt peeling and loose cold patch material caused by water erosion, and effectively improve the performance of the cold patch material in rainy and humid environments. The addition of cement increases the bonding force between the components in the cold patch material. It can interact with asphalt, allowing the asphalt to better wrap the aggregate, improve the adhesion between the aggregate and asphalt, and allow the cold patch material to form a tighter overall structure. This enhanced bonding property helps to improve the compressive and shear strength of the cold patch material, making it difficult for the components to separate when bearing vehicle loads, thereby improving the stability and durability of the repaired road surface. At the same time, cement and mineral powder work together to increase the density of the cold patch material and improve the overall strength of the cold patch material. When repairing the road surface, it can better withstand vehicle rolling and wear, reduce road deformation and damage, and extend the service life of the repaired road surface. The preferred mineral powder can be

[0013] Furthermore, the tackifier is petroleum resin or epoxy resin, which improves low-temperature adhesion and water damage resistance; the asphalt material is one or more of emulsified asphalt, solvent-based asphalt, SBS modified asphalt and rubber asphalt, and the asphalt material provides adhesion and wraps the aggregate to form an overall structure.

[0014] Furthermore, the anti-stripping agent is slaked lime or liquid amines to prevent the aggregate from peeling off from asphalt. Both slaked lime (calcium hydroxide) and liquid amines are polar and can chemically adsorb with aggregate and asphalt. The calcium ions in slaked lime can combine with the active groups on the surface of the aggregate and react with the acidic components in the asphalt to form a chemical bond between the aggregate and the asphalt, thereby enhancing the bonding force between the two. Liquid amine molecules can also interact with aggregate and asphalt, and build a "bridge" between them through chemical reactions, so that the aggregate and asphalt are closely connected, effectively preventing the peeling phenomenon from occurring; the two types of anti-stripping agents can improve the interfacial properties between aggregate and asphalt. They can reduce the interfacial tension between aggregate and asphalt, so that asphalt can better wrap the aggregate and form a more stable structure. In a humid environment, moisture will weaken the bonding between aggregate and asphalt, but slaked lime and liquid amines can preferentially react with moisture, reduce moisture damage to the interface, maintain the stability of the interface, and thus prevent the aggregate from peeling off from asphalt.

[0015] The anti-aging agent is carbon black or an antioxidant, which delays ultraviolet aging. Carbon black has good ultraviolet absorption ability and can effectively block the direct irradiation of ultraviolet rays on materials. When carbon black is added to materials such as cold asphalt patching materials, it can convert the energy of ultraviolet rays into heat energy and dissipate it, reducing the damage of ultraviolet rays to components such as asphalt and aggregates. Carbon black can also improve the weather resistance of materials and enhance their antioxidant performance. Under long-term sunlight irradiation, carbon black can inhibit the oxidation reaction of asphalt, slow down the hardening and embrittlement process of asphalt, thereby maintaining the flexibility and adhesion of materials, effectively delaying the performance decline caused by ultraviolet aging of materials, and extending the service life of materials; Antioxidants can inhibit or slow down the oxidation process of materials under the action of ultraviolet rays through their own chemical reactions. It can capture free radicals generated by ultraviolet irradiation, prevent the chain reaction initiated by free radicals, and reduce the oxidative degradation of components such as asphalt. Antioxidants can interrupt the chain transfer of oxidation reactions, protect the molecular structure of asphalt, and keep it in good performance. In practical applications, antioxidants can effectively prevent aging phenomena such as discoloration, hardening, and embrittlement of materials under ultraviolet irradiation, maintain the physical and chemical stability of materials, and ensure that materials can still maintain good performance after long-term use in outdoor environments.

[0016] Furthermore, the curing regulator is an organic metal salt, preferably one or more of cobalt naphthenate, zinc naphthenate, and lead octoate, which is used to control the solvent evaporation rate. The organic metal salt can interact with solvent molecules to change the evaporation environment and rate of the solvent; By controlling the solvent evaporation rate, the organic metal salt can avoid problems caused by too fast or too slow solvent evaporation. If the solvent evaporates too fast, the material may have surface skinning and incomplete internal curing, affecting the overall performance of the material; If the evaporation is too slow, it will extend the construction period and increase costs. Using an organic metal salt to precisely control the solvent evaporation can make the material cure evenly, improve the hardness, adhesion, water resistance and other properties of the material, and ensure the stable quality of the material.

[0017] Furthermore, in low-temperature regions, the tackifier is increased to 3%, and slow-evaporation solvent bio-oil is adopted, mainly to address the impact of low temperature on the performance of cold patch materials. Low temperature can reduce the viscosity of asphalt, resulting in poor bonding of cold patch materials and difficulty in firmly bonding with the road surface. Increasing the proportion of tackifiers (such as petroleum resin, epoxy resin) to 3% can significantly improve the low-temperature bonding property of cold patch materials, enhance their adhesion to the road surface, and avoid problems such as peeling and loosening in low-temperature environments. Adopting slow-evaporation solvent bio-oil can slow down the evaporation rate of the solvent. Because under low-temperature conditions, too slow evaporation of the solvent will prolong the curing time of cold patch materials, while too fast evaporation may cause the cold patch materials to lose their viscosity before sufficient bonding. As a slow-evaporation solvent, bio-oil allows cold patch materials to have sufficient time for bonding and curing at low temperature, forming a stable structure, and effectively improving the performance of cold patch materials in low-temperature regions; in rainy regions, the proportion of mineral powder and cement is increased to 8%, mainly to enhance the water damage resistance of cold patch materials. Long-term erosion by rainwater can cause the aggregate in cold patch materials to peel off from the asphalt, reducing the performance of cold patch materials. Mineral powder and cement can improve the adhesion between asphalt and aggregate and increase the density of cold patch materials. Increasing their proportion to 8% can enhance the water stability of cold patch materials and reduce the damage of moisture to the structure of cold patch materials. Cement can also play a role in filling voids to a certain extent, further preventing the intrusion of moisture, thus effectively enhancing the water damage resistance of cold patch materials in rainy regions and extending the service life of the road after repair.

[0018] Furthermore, during shallow patching, the proportion of fine aggregate is increased to 50%, and the asphalt binder dosage is reduced to 4%. When performing shallow patching, increasing the proportion of fine aggregate to 50% can better fill the small voids on the shallow surface of the road surface, enhancing the adhesion and compactness between the patching material and the original road surface. The increase in fine aggregate can make the surface of the patching layer smoother, reducing the unevenness of the road surface and improving the driving comfort and safety. At the same time, appropriately reducing the asphalt binder dosage to 4% can avoid the phenomenon of bleeding caused by excessive asphalt in the shallow layer and ensure the anti-skid performance of the road surface. Since the shallow layer is directly in contact with the vehicle tires, if there is too much asphalt, especially in high-temperature weather during vehicle driving, bleeding is likely to occur, resulting in a decrease in the anti-skid performance of the road surface and increasing the potential safety hazards during driving. Reducing the asphalt dosage can effectively reduce the occurrence of this situation and ensure the stable performance of the shallow road surface after patching; during deep patching, the proportion of coarse aggregate is increased to 60%, and the asphalt dosage is increased to 7%. When performing deep patching, increasing the proportion of coarse aggregate to 60% is because coarse aggregate has high strength and stability, which can provide better skeleton support for deep patching. Under the condition of large pressure in the deep layer, the coarse aggregate can effectively disperse the pressure, enhancing the bearing capacity of the patching structure and preventing problems such as deformation and settlement of the road surface under the action of vehicle loads. Increasing the asphalt dosage to 7% is considered because better adhesion is required for deep patching to ensure the firm connection between the aggregates. More asphalt can better wrap the coarse aggregate, forming a stable structure, enhancing the overall cohesion and durability of the patching material, enabling the deep patching part to withstand the action of vehicle loads and the natural environment for a long time stably, and extending the service life of the road.

[0019] Furthermore, adding waste rubber powder to replace part of the aggregate. Waste rubber powder has good elasticity. Adding it to the material to replace part of the aggregate can significantly improve the overall elasticity of the material. Taking asphalt cold patching material as an example, when patching a road, after adding waste rubber powder, the flexibility of the cold patching material is enhanced. When a vehicle drives on the patched road surface, the material can better adapt to the repeated action of vehicle loads, acting like a spring to provide a buffering effect and reducing cracks and deformations on the road surface caused by vehicle rolling. This improvement in elasticity not only enhances the service performance of the road but also effectively reduces the bumpiness during vehicle driving, improving driving comfort and safety. Adding waste rubber powder is an effective recycling of waste resources. Waste rubber powder usually comes from rubber products such as waste tires. If a large amount of waste rubber is not properly treated, it will cause environmental pollution. Applying it to replace part of the aggregate finds a new way out for waste rubber, reducing the accumulation of waste. This not only saves natural aggregate resources, reduces the demand for new aggregate mining, protects the ecological environment, but also conforms to the concept of sustainable development, reducing production costs to a certain extent and having good economic and environmental benefits.

[0020] On the other hand, the present invention provides a method for preparing the above-mentioned high-performance solvent-based cold asphalt patch material, which includes the following steps: at normal temperature of 20 - 30 °C, add the weighed coarse aggregate, fine aggregate and mineral powder into a forced mixer, and stir at a speed of 300 - 500 r / min for 5 - 10 minutes; then add the asphalt binder and stir at a speed of 200 - 400 r / min for 10 - 15 minutes; finally, add the tackifier, anti-stripping agent, anti-aging agent and curing regulator, and stir at a speed of 150 - 300 r / min for 5 - 8 minutes; seal and package the prepared cold patch material.

[0021] The present invention further provides an application of the above-mentioned cold patch material in road repair. During the repair process, first clean the road pothole, then fill the cold patch material, and finally compact it with a plate compactor or a roller, and cure for 2 - 24 hours.

[0022] Beneficial effects

[0023] Performance improvement: By optimizing the formula, the cold patch material of the present invention has good adhesiveness in low-temperature environments, can effectively resist rain erosion, and significantly enhances the water damage resistance. At the same time, the addition of the anti-aging agent greatly delays the aging speed of the cold patch material and extends the service life of the repaired road surface.

[0024] Environmental protection advantages: While meeting high performance, the present invention reduces the emissions of volatile organic compounds (VOCs) and the pollution to the environment by reasonably selecting raw materials and optimizing the preparation process.

[0025] Cost controllability: On the premise of ensuring performance, by reasonably selecting raw materials and optimizing the ratio, the relationship between cost and performance is balanced, the cost performance of the product is improved, and it is suitable for large-scale road maintenance projects. Specific embodiments

[0026] The following combines examples to further describe in detail the specific embodiments of the present invention. The following examples are used to illustrate the present invention but not to limit the scope of the present invention.

[0027] It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups.

[0028] Only one of them is schematically illustrated, or only one of them is marked. In this article, "one" not only means "only this one", but also can mean "more than one" situation.

[0029] It should also be further understood that the term "and / or" used in the specification and appended claims of this application refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0030] In addition, in the description of this application, the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation manners of the present invention will be described below with reference to specific embodiments.

[0032] Example 1

[0033] Raw material preparation: Prepare 5% solvent-based asphalt (where diesel accounts for 25% of the asphalt mass), 48% coarse aggregate (particle size 4.75 - 13.2 mm, ratio of basalt to limestone is 50:50), 37% fine aggregate (particle size 0.075 - 4.75 mm, ratio of manufactured sand to stone chips is 60:40), 5% mineral powder (where cement content is 50%), 1.5% petroleum resin as tackifier, 0.8% slaked lime as anti-stripping agent, 0.3% carbon black as anti-aging agent, and 0.2% zinc naphthenate as curing regulator.

[0034] Preparation process: Add the coarse aggregate, fine aggregate, and mineral powder into a forced mixer and stir at a speed of 400 r / min for 8 minutes; add the solvent-based asphalt and stir at a speed of 300 r / min for 12 minutes; then add the tackifier, anti-stripping agent, anti-aging agent, and curing regulator and stir at a speed of 200 r / min for 6 minutes; finally, seal and package the prepared cold patch material.

[0035] Example 2

[0036] Raw material preparation: Prepare 5% solvent-based asphalt (where bio-oil accounts for 25% of the asphalt mass), 48% coarse aggregate (particle size 4.75 - 13.2 mm, ratio of basalt to limestone is 50:50), 37% fine aggregate (particle size 0.075 - 4.75 mm, ratio of manufactured sand to stone chips is 60:40), 5% mineral powder (where cement content is 50%), 3% petroleum resin as tackifier, 0.8% slaked lime as anti-stripping agent, 0.3% carbon black as anti-aging agent, and 0.2% zinc naphthenate as curing regulator.

[0037] Preparation process: Prepare according to the mixing equipment and mixing parameters of Example 1, that is, first stir the coarse aggregate, fine aggregate, and mineral powder evenly, then add the asphalt, and finally add the additives and stir, and seal and package after completion.

[0038] Example 3

[0039] Raw material preparation: Prepare 5% solvent-based asphalt (where diesel accounts for 25% of the asphalt mass), 48% coarse aggregate (particle size 4.75 - 13.2 mm, with a ratio of basalt to limestone of 50:50), 37% fine aggregate (particle size 0.075 - 4.75 mm, with a ratio of manufactured sand to stone chips of 60:40), 8% mineral powder (where the cement content is 50%), 1.5% petroleum resin as a tackifier, 0.8% slaked lime as an anti-stripping agent, 0.3% carbon black as an anti-aging agent, and 0.2% zinc naphthenate as a curing regulator.

[0040] Preparation process: Keep consistent with the preparation process and stirring parameters of Example 1 to ensure the uniformity and stability of the cold patch material.

[0041] Example 4

[0042] Raw material preparation: Prepare 4% solvent-based asphalt (where diesel accounts for 25% of the asphalt mass), 48% coarse aggregate (particle size 4.75 - 13.2 mm, with a ratio of basalt to limestone of 50:50), 50% fine aggregate (particle size 0.075 - 4.75 mm, with a ratio of manufactured sand to stone chips of 60:40), 5% mineral powder (where the cement content is 50%), 1.5% petroleum resin as a tackifier, 0.8% slaked lime as an anti-stripping agent, 0.3% carbon black as an anti-aging agent, and 0.2% zinc naphthenate as a curing regulator.

[0043] Preparation process: Keep consistent with the preparation process and stirring parameters of Example 1 to ensure the uniformity and stability of the cold patch material.

[0044] Example 5

[0045] Raw material preparation: Prepare 6% solvent-based asphalt (where diesel accounts for 25% of the asphalt mass), 60% coarse aggregate (particle size 4.75 - 13.2 mm, with a ratio of basalt to limestone of 50:50), 37% fine aggregate (particle size 0.075 - 4.75 mm, with a ratio of manufactured sand to stone chips of 60:40), 5% mineral powder (where the cement content is 50%), 1.5% petroleum resin as a tackifier, 0.8% slaked lime as an anti-stripping agent, 0.3% carbon black as an anti-aging agent, and 0.2% zinc naphthenate as a curing regulator.

[0046] Preparation process: Keep consistent with the preparation process and stirring parameters of Example 1 to ensure the uniformity and stability of the cold patch material.

[0047] Comparative Example 1:

[0048] Prepare 5% solvent-based asphalt (where diesel accounts for 25% of the asphalt mass), 48% coarse aggregate (particle size 4.75 - 13.2 mm, with a 50:50 ratio of basalt to limestone), 37% fine aggregate (particle size 0.075 - 4.75 mm, with a 60:40 ratio of manufactured sand to stone chips), 5% mineral powder (without cement), 1.5% petroleum resin as tackifier, 0.8% slaked lime as anti-stripping agent, 0.3% carbon black as antioxidant, and 0.2% zinc naphthenate as curing regulator.

[0049] Preparation process: Keep consistent with the preparation process and stirring parameters of Example 1 to ensure the uniformity and stability of the cold patch material.

[0050] Comparative Example 2:

[0051] Prepare 5% solvent-based asphalt (where diesel accounts for 25% of the asphalt mass), 48% coarse aggregate (particle size 4.75 - 13.2 mm, with a 50:50 ratio of basalt to limestone), 37% fine aggregate (particle size 0.075 - 4.75 mm, with a 60:40 ratio of manufactured sand to stone chips), 5% mineral powder (with a cement content of 50%), 1.5% petroleum resin as tackifier, 0.8% slaked lime as anti-stripping agent, 0.3% carbon black as antioxidant, but no curing regulator is added.

[0052] Preparation process: Keep consistent with the preparation process and stirring parameters of Example 1 to ensure the uniformity and stability of the cold patch material.

[0053] Comparative Example 3:

[0054] Prepare 5% solvent-based asphalt (where diesel accounts for 25% of the asphalt mass), 48% coarse aggregate (particle size 4.75 - 13.2 mm, with a 50:50 ratio of basalt to limestone), 37% fine aggregate (particle size 0.075 - 4.75 mm, with a 60:40 ratio of manufactured sand to stone chips), 5% mineral powder (with a cement content of 50%), 1.5% petroleum resin as tackifier, 0.3% carbon black as antioxidant, 0.2% zinc naphthenate as curing regulator, but no anti-stripping agent is added.

[0055] Preparation process: Keep consistent with the preparation process and stirring parameters of Example 1 to ensure the uniformity and stability of the cold patch material.

[0056] Performance test

[0057] Marshall test: To test the stability (kN) of cold patch materials, reflecting the anti-deformation ability of the materials. Cantabro test: To calculate the scatter loss rate (%), evaluating the anti-loosening performance of the mixture. Immersion Marshall test: To measure the residual stability ratio after immersion (%), evaluating the anti-water damage ability. Freeze-thaw splitting test: To calculate the freeze-thaw splitting strength ratio (%), reflecting the anti-water damage performance at low temperature. Natural aging test: To simulate the mass retention rate after ultraviolet aging (%), evaluating the anti-aging performance.

[0058] Experimental data:

[0059]

[0060] Marshall stability and flow value:

[0061] In Example 4, the asphalt content is 4%, in Example 1 it is 5%, and in Example 5 it is 6%. In terms of Marshall stability, it is 8.0 kN in Example 4, 8.5 kN in Example 1, and 9.0 kN in Example 5; in terms of Cantabro scatter loss, it is 15% in Example 4, 12% in Example 1, and 11% in Example 5. As the asphalt content increases, the bondability of the cold patch materials is enhanced because more asphalt can better wrap the aggregates. In terms of anti-water damage performance, the residual stability of the immersion Marshall test is 82% in Example 4, 86% in Example 1, and 90% in Example 5; the freeze-thaw splitting strength ratio is 79% in Example 4, 83% in Example 1, and 88% in Example 5. A higher asphalt content helps to improve the anti-water damage performance and enhance the ability of the structure to resist water erosion. In terms of anti-aging performance, the retention rate of the Marshall stability after aging is 75% in Example 4, 80% in Example 1, and 85% in Example 5. A higher asphalt content makes the cold patch materials have better anti-aging performance and can maintain better structural stability in an aging environment.

[0062] Example 1: The mineral powder content is 5%, and the cement accounts for 50% of the mineral powder. Comparative Example 1: The mineral powder contains no cement. Example 3: The mineral powder content is increased to 8% (the proportion of cement remains unchanged). In terms of Marshall stability, it is 8.5 kN in Example 1, 7.8 kN in Comparative Example 1, and 8.8 kN in Example 3; for the Cantabro loss, it is 12% in Example 1, 18% in Comparative Example 1, and 10% in Example 3. The addition of cement enhances the adhesiveness of the cold patch material, and with the increase in the content of mineral powder and cement, the adhesiveness is further improved. In terms of water damage resistance, the residual stability of the immersed Marshall is 86% in Example 1, 76% in Comparative Example 1, and 89% in Example 3; the freeze-thaw splitting strength ratio is 83% in Example 1, 72% in Comparative Example 1, and 86% in Example 3, indicating that cement and mineral powder can effectively improve the water damage resistance of the cold patch material. In terms of anti-aging performance, the retention rate of the Marshall stability after aging is 80% in Example 1, 70% in Comparative Example 1, and 83% in Example 3. The increase in the content of mineral powder and cement improves the anti-aging performance of the cold patch material, enabling the material to still maintain a relatively high strength after aging. Water damage resistance:

[0063] In Comparative Example 2, no curing regulator was added. Compared with Example 1, the Marshall stability decreased from 8.5 kN to 8.2 kN, the Cantabro loss increased from 12% to 16%, the residual stability of the immersed Marshall decreased from 86% to 80%, the freeze-thaw splitting strength ratio decreased from 83% to 76%, and the retention rate of the Marshall stability after aging decreased from 80% to 73%. This indicates that the curing regulator has a positive impact on the adhesiveness, water damage resistance, and anti-aging performance of the cold patch material, and can promote the curing and molding of the cold patch material and enhance the structural stability. In Comparative Example 3, no anti-stripping agent was added. The Marshall stability was 8.1 kN, the Cantabro loss was 17%, the residual stability of the immersed Marshall was 78%, the freeze-thaw splitting strength ratio was 74%, and the retention rate of the Marshall stability after aging was 71%, all of which were lower than those in Example 1, indicating that the anti-stripping agent is crucial for improving the adhesiveness and water damage resistance of the cold patch material, can enhance the adhesion between the aggregate and the asphalt, and reduce the damage of water to the adhesion.

[0064] Through the above experiments, targeted design of cold patch materials can be carried out:

[0065] In rainy areas: Adopt a high proportion of mineral powder and cement (such as Example 3) combined with an anti-stripping agent to improve the water damage resistance ability (the residual stability of immersion is 89%).

[0066] In low-temperature areas: Increase the content of tackifier (such as Example 3) and bio-oil solvent to optimize the low-temperature adhesiveness (the freeze-thaw splitting strength ratio is 86%).

[0067] For shallow repairs: Appropriately increase the proportion of fine aggregate (such as Example 4), but the asphalt content needs to be controlled (4% - 5%) to avoid looseness.

[0068] Deep repair: By adopting a high coarse aggregate ratio (such as in Example 5) + a high asphalt content (6%), the structural stability is enhanced (stability: 9.0 kN).

[0069] The embodiments described above are some, but not all, of the embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

Claims

1. A high-performance solvent-based cold asphalt patching material, characterized in that, By mass percentage, it includes the following components: 3%-6% of asphalt binder, which is composed of asphalt material and solvent, and the solvent accounts for 20%-30% of the asphalt binder; 40%-60% of coarse aggregate with a particle size of 4.75-13.2mm; 30%-50% of fine aggregate with a particle size of 0.075-4.75mm; 3%-8% of mineral powder with a particle size of <0.075mm, and 40%-60% of cement is contained in the mineral powder; 1%-3% of tackifier; 0.5%-1% of anti-stripping agent; 0.2%-0.5% of anti-aging agent; 0.1%-0.3% of curing regulator.

2. The high-performance solvent-based cold asphalt patching material according to claim 1, characterized in that, The solvent in the solvent-based asphalt is one or more of kerosene, diesel, bio-oil and vegetable oil; the coarse aggregate is composed of basalt and limestone; the fine aggregate is composed of manufactured sand and stone chips; the mineral powder is a mixture composed of limestone powder and cement.

3. The high-performance solvent-based cold asphalt patching material according to claim 1, characterized in that, The tackifier is petroleum resin or epoxy resin; the asphalt material is one or more of emulsified asphalt, solvent-based asphalt, SBS modified asphalt and rubber asphalt.

4. The high-performance solvent-based cold asphalt patching material according to claim 1, wherein The anti-stripping agent is slaked lime or liquid amine, and the anti-aging agent is carbon black or antioxidant.

5. The high-performance solvent-based cold asphalt patching material according to claim 1, characterized in that, The curing regulator is an organic metal salt; preferably one or more of cobalt naphthenate, zinc naphthenate and lead octoate.

6. The high-performance solvent-based cold asphalt patching material according to claim 1, wherein In low-temperature regions, the dosage of the tackifier is increased to 3%, and slow-volatile solvent bio-oil is used; in rainy regions, the proportion of the mineral powder is increased to 8% to enhance the water damage resistance.

7. The high-performance solvent-based cold asphalt patching material according to claim 1, characterized in that, During shallow repair, the proportion of fine aggregate is increased to 50%, and the dosage of asphalt binder is reduced to 4%; during deep repair, the proportion of coarse aggregate is increased to 60%, and the asphalt dosage is increased to 7%.

8. The high-performance solvent-based cold asphalt patching material according to claim 1, wherein The asphalt cold patch can replace part of the aggregate by adding waste rubber powder to improve elasticity.

9. A preparation method of a high-performance solvent-based cold asphalt patching material according to any one of claims 1-8, characterized in that, It includes the following steps: At normal temperature of 20-30°C, add the weighed coarse aggregate, fine aggregate and mineral powder into a forced mixer, and stir at a speed of 300-500r / min for 5-10 minutes; then add the asphalt binder and stir at a speed of 200-400r / min for 10-15 minutes; finally add the tackifier, anti-stripping agent, anti-aging agent and curing regulator, and stir at a speed of 150-300r / min for 5-8 minutes; seal and package the prepared cold patch.

10. Use of the cold patching material according to any one of claims 1 to 8 in road repair, characterized in that, During the repair process, first clean the road pothole, then fill the cold patch, and finally compact it with a plate compactor or roller and cure for 2-24 hours.

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