Composite asphalt cold patch material and preparation method thereof

Abstract

The invention discloses a composite asphalt cold patch material and a preparation method thereof, and relates to the technical field of road building materials. The invention discloses a composite asphalt cold patch material. The invention discloses a high-strength concrete, which is prepared from the following raw materials in parts by weight: 10 to 15 parts of modified asphalt, 27 to 33 parts of basalt aggregate, 18 to 22 parts of modified basalt aggregate, 15 to 20 parts of limestone machine-made sand, 3 to 6 parts of early-strength Portland cement, 1 to 3 parts of styrene-butadiene-styrene block copolymer modifier, 0.8 to 1.5 parts of epoxy resin E-44, 0.8 to 1.5 parts of polyamide 650, 0.3 to 0.8 part of nano silicon dioxide and 0.2 to 0.5 part of propylene diamine. The coating is prepared from the following components in parts by weight: 0.1-0.3 part of an anti-ultraviolet agent UV-531, 0.05-0.15 part of polydimethylsiloxane, 2-2.5 parts of diesel oil and 0.3-0.5 part of acetone. According to the composite asphalt cold patch material, the raw materials are scientifically matched, the modified asphalt and the modified basalt aggregate have a synergistic effect, the composite powder and the epoxy curing system are supplemented, curing is rapid, bonding is firm, and the looseness meets the construction requirement. The early strength, the ultraviolet resistance and the loss resistance are excellent, the performance is stable, and the durability and practicability requirements of pavement repairing can be efficiently met.

Description

Technical Field

[0001] This invention relates to the field of road construction materials technology, specifically to a composite asphalt cold patching material and its preparation method. Background Technology

[0002] In the field of road engineering, road surfaces, as the core carrier of traffic, endure repeated crushing and impacts from vehicle loads over long periods, while also facing continuous erosion from a complex natural environment. High temperatures and intense sunlight in summer can cause asphalt to soften and flow, while low temperatures and freezing temperatures in winter can lead to material brittleness and cracking. Rainwater infiltration can damage the interfacial bond between aggregates and binders, and prolonged exposure to ultraviolet radiation accelerates asphalt aging and decomposition. Under the combined effect of these factors, road surfaces are highly susceptible to defects such as cracks, potholes, loosening, and spalling. If these defects are not repaired promptly, they will not only reduce road comfort and may cause traffic accidents, but also exacerbate structural damage to the road surface, leading to significantly increased maintenance costs and a shortened overall service life of the road.

[0003] Traditional cold-applied asphalt patching materials are widely used in road repair due to their advantages such as room-temperature application, ease of operation, no need for large heating equipment, and rapid emergency repair capabilities. However, their performance has several shortcomings due to limitations in formulation design and preparation processes. In terms of bonding performance, traditional cold-applied asphalt patching materials often use unmodified base asphalt as a binder, which has insufficient molecular structural stability and weak interfacial adhesion with aggregates. After repair, under the influence of heavy vehicle traffic and rainwater erosion, problems such as bonding failure, detachment, and shoving can easily occur. The repair life is usually only a few months, which is difficult to meet the requirements for long-term use.

[0004] In terms of curing efficiency, traditional materials cure slowly, often requiring several days or even weeks to reach their design strength. During this time, the road surface cannot bear the load normally, affecting traffic flow and potentially causing damage to the repair layer due to external interference, increasing secondary maintenance costs. Regarding aging resistance and durability, traditional cold-applied patch materials lack effective UV stabilizers and anti-aging fillers. Long-term exposure to the natural environment can cause asphalt to oxidize and become embrittled, and aggregates to loosen and peel off, leading to cracking and damage in the repair layer. This makes them unsuitable for long-term use under different climatic conditions.

[0005] Furthermore, traditional cold patch materials mostly use unmodified natural aggregates with low surface activity, insufficient gradation rationality, and poor compatibility with binders, further reducing the overall mechanical properties of the material. Some formulations also fail to prioritize the utilization of recycled resources, neglecting to effectively integrate recycled materials such as waste tire rubber powder, resulting in resource waste and contradicting environmental protection trends. Simultaneously, with increasing traffic volume, a rising proportion of heavy-duty vehicles, and higher demands for road maintenance quality and efficiency, the performance shortcomings of traditional cold patch materials are becoming increasingly apparent, failing to meet the needs of high-quality, long-lasting, and fast-recovery road repairs. Therefore, developing a composite asphalt cold patch material with superior comprehensive performance has become an urgent technical challenge for the industry. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a composite asphalt cold patching material and its preparation method, solving the problems of insufficient adhesion, slow curing, and poor durability of traditional asphalt cold patching materials.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A composite asphalt cold patching material comprises the following raw materials in parts by weight: 10-15 parts modified asphalt, 27-33 parts basalt aggregate, 18-22 parts modified basalt aggregate, 15-20 parts limestone manufactured sand, 3-6 parts early-strength silicate cement, 1-3 parts styrene-butadiene-styrene block copolymer (SBS) modifier, 0.8-1.5 parts epoxy resin E-44, 0.8-1.5 parts polyamide 650, 0.3-0.8 parts nano silica, 0.2-0.5 parts propylenediamine, 0.1-0.3 parts UV stabilizer UV-531, 0.05-0.15 parts polydimethylsiloxane, 2-2.5 parts diesel oil, and 0.3-0.5 parts acetone.

[0008] Furthermore, the modified asphalt is prepared using the following specific steps: A1. Heat 70# base asphalt to 160-170℃, add waste tire rubber powder that has passed through an 80-mesh sieve, and shear and disperse it using a high-speed shear machine at 3000-3500 r / min for 1 hour, keeping the temperature stable during this period to allow the rubber powder to fully swell and improve the asphalt's low-temperature crack resistance and elasticity; slowly add a mixture of maleic anhydride and xylene, raise the temperature to 175-185℃, and react at a constant temperature for 2 hours. Xylene assists in the uniform dispersion of maleic anhydride, which introduces polar groups into the asphalt; then lower the temperature to 165-175℃, add diethylenetriamine, and stir to react for 1.5 hours to enhance the degree of cross-linking of asphalt molecules and improve thermal stability, thus obtaining the first modified asphalt; A2. Take the first modified asphalt, cool it to 140-150℃, add nano-montmorillonite, and ultrasonically disperse for 30 minutes to enhance the mechanical strength and impermeability of the asphalt; dilute 40% solid content styrene-acrylate emulsion with deionized water, and slowly spray it into the asphalt system while stirring at a speed of 1500-2000 r / min, maintaining the temperature at 140-150℃ for 1 hour to improve the weather resistance of the asphalt; then add tetrabutyl titanate coupling agent, raise the temperature to 145-155℃ and react for 1 hour to improve the interfacial bonding between nano-montmorillonite and asphalt, prevent delamination, and obtain the second modified asphalt; A3. Take the second modified asphalt and cool it to 120-130℃. Add a mixture of polyethylene glycol 400 and anhydrous ethanol and stir at 1000r / min for 30min to optimize the asphalt fluidity. Use a constant pressure dropping funnel to slowly add MDI-type isocyanate to avoid excessive local reaction, promote cross-linking of asphalt molecules, and improve adhesion. Heat to 125-135℃ and stir for 40min to ensure sufficient cross-linking. Then add tributyl phosphate and stir at 800r / min for 20min to eliminate air bubbles in the system and improve the density of the asphalt to obtain modified asphalt.

[0009] Furthermore, the modified basalt aggregate is prepared using the following specific steps: B1. Rinse the basalt aggregate with clean water to remove impurities, dry it in an oven at 105℃ for 2 hours, and cool it to room temperature before placing it in a high-speed mixer. Mix silane coupling agent KH-550, 1 mol / L hydrochloric acid, and deionized water, and stir for 30 minutes to form a hydrolysate. Spray the hydrolysate onto the surface of the aggregate, start the mixer, and stir at 800-1000 r / min for 20 minutes to improve the surface activity and interfacial compatibility of the aggregate. At the same time, add nano-calcium carbonate and continue stirring for 20 minutes to fill the pores of the aggregate, enhance the density and wear resistance of the aggregate, and obtain the first modified basalt aggregate. B2. Take the first modified basalt aggregate and preheat it in an oven at 60-70℃ for 30 minutes. After taking it out, put it into a mixer. Mix and dilute epoxy resin E-51 with acetone, add polyamide 650 and stir evenly to prepare an epoxy curing system. Spray the epoxy curing system evenly onto the surface of the preheated aggregate. Adjust the mixer speed to 1200-1500 r / min and stir for 30 minutes to form a tough coating on the surface of the aggregate and improve its resistance to wear. Then immediately add quartz sand powder that has passed through a 120-mesh sieve and continue stirring for 20 minutes. Keep it at 80-90℃ for 1 hour to complete the curing, enhance the surface hardness of the aggregate, optimize the bonding with asphalt, and obtain the second modified basalt aggregate. B3. Cool the second modified basalt aggregate to 40-50℃ and place it in a mixer. Add 5% (w / w) of polyvinyl alcohol 1788 aqueous solution and stir at 800 r / min for 15 min to improve the surface adhesion of the aggregate. Then add 0.5 mg / mL of graphene oxide dispersion, sonicate at 300W and stir at 1200 r / min for 20 min to promote uniform dispersion and enhance the aggregate's UV resistance and thermal conductivity. Then add propylene glycol and stir at 800 r / min for 15 min. Finally, let the aggregate air dry naturally to avoid moisture affecting the curing efficiency of the cold patching material, and obtain the modified basalt aggregate.

[0010] Furthermore, the early-strength silicate cement has a strength grade of 42.5R and a specific surface area ≥350m². 2 / kg, ensuring reactivity, initial setting time ≥45min to allow for construction operation window, final setting time ≤6h, accelerating the formation of cold patch strength, ensuring 24h curing degree meets the standard; synergistic with propylenediamine to further enhance early strength performance, meeting the needs of rapid road repair and quick reopening to traffic.

[0011] Furthermore, the NCO content of the MDI-type isocyanate in A3 is 29%-31%, ensuring sufficient reaction with asphalt molecules, significantly improving adhesion. Moreover, the activity of the MDI-type isocyanate is balanced and easy to control, with good compatibility with asphalt, and the crosslinking density can be precisely adjusted. When adding, a constant pressure dropping funnel is used, and the dropping speed is controlled at 0.3-0.5 ml / min, while maintaining a stable stirring speed during the dropping process.

[0012] Furthermore, the ratio of 70# base asphalt, waste tire rubber powder, maleic anhydride, xylene, and diethylenetriamine in A1 is 1000g: 400-500g: 20-30ml: 30-40ml: 15-25ml.

[0013] Furthermore, the ratio of the first modified asphalt, nano-montmorillonite, styrene-acrylate emulsion, deionized water, and tetrabutyl titanate coupling agent in A2 is 1000g: 30-40g: 50-60ml: 80-100ml: 10-15ml.

[0014] Furthermore, the ratio of the amount of the second modified asphalt, polyethylene glycol 400, anhydrous ethanol, MDI-type isocyanate, and tributyl phosphate in A3 is 1000g: 25-35g: 15-20ml: 18-28ml: 8-12ml.

[0015] Furthermore, the ratio of basalt aggregate, silane coupling agent KH-550, hydrochloric acid, deionized water, and nano-calcium carbonate in B1 is 1000g: 20-30ml: 5-8ml: 100-120ml: 15-20g.

[0016] Furthermore, the ratio of the first modified basalt aggregate, epoxy resin E-51, acetone, polyamide 650, and quartz sand powder in B2 is 1000g: 30-40ml: 10-15ml: 25-35ml: 15-25g.

[0017] Furthermore, the ratio of the second modified basalt aggregate, polyvinyl alcohol 1788 aqueous solution, graphene oxide dispersion, and propylene glycol in B3 is 1000g: 40-50ml: 10-15g: 8-12ml.

[0018] A method for preparing a composite asphalt cold patching material specifically includes the following steps: S1. Pass 27-33 parts of basalt aggregate and 18-22 parts of modified basalt aggregate through a 10-mesh sieve, and pass 15-20 parts of limestone manufactured sand through a 100-mesh sieve. Then put them together in an oven at 105℃ and dry for 2 hours. After cooling to room temperature, mix them evenly to obtain pretreated mixed aggregate. Grind 3-6 parts of early-strength silicate cement, 0.3-0.8 parts of nano-silica, 0.2-0.5 parts of propylenediamine, and 0.1-0.3 parts of UV inhibitor UV-531 through a 200-mesh sieve, mix them evenly to make a composite powder, ensure the powder dispersibility, and improve the material's impermeability and early strength. Mix 0.8-1.5 parts of epoxy resin E-44 with 0.8-1.5 parts of polyamide 650, add 0.3-0.5 parts of acetone to dilute, and stir for 10 minutes to prepare an epoxy curing agent system; S2. Place 10-15 parts of modified asphalt into a reaction vessel, add 2-2.5 parts of diesel oil, and stir to adjust the viscosity to 1500-2500 mPa·s at 60℃ to meet the mixing and blending requirements for room temperature construction. Stir at 1000 r / min for 15 minutes to ensure uniform viscosity. Add 1-3 parts of SBS modifier, maintain the temperature at 87-93℃, and shear with a high-speed shear machine at 2500 r / min for 30 minutes to enhance the elasticity and high-temperature anti-flow properties of the asphalt. Then raise the temperature to 100℃ and hold for 10 minutes to promote swelling. Then lower the temperature to 80℃, add the prepared epoxy curing agent system, adjust the stirring speed to 1500 r / min, and react for 20 minutes to form a composite bonding system. Ensure that the system has a curing degree of ≥80% at 25℃ for 24 hours to meet the requirements for rapid strength formation. S3. Add the pretreated mixed aggregate to the composite bonding system in the reactor. Reduce the stirring speed to 800 r / min and maintain the temperature at 70-80℃ for 30 minutes to initially coat the aggregate surface with the binder and avoid weak points caused by local lack of binder. Add the composite powder in three batches, with a 10-minute interval between each batch, and control the temperature at 65-75℃. Finally, add 0.05-0.15 parts of polydimethylsiloxane, adjust the stirring speed to 600 r / min, and continue stirring for 15 minutes to eliminate air bubbles generated during the mixing process and optimize workability and material density. S4. Close the heating jacket, start the reactor cooling water device, and maintain stirring at 200r / min for maturation. Within 20 minutes, reduce the material temperature to 45℃ to prevent over-maturation. During this period, take samples to test the looseness of the material. It is qualified if it can be formed into a ball when squeezed by hand and crumbles when released. Avoid local curing differences or construction difficulties caused by uneven temperature. S5. After curing, quickly pack the material into moisture-proof woven bags, seal the packaging to prevent moisture intrusion and material dampness, ensure the storage stability of the cold patch material, extend its shelf life, and obtain composite asphalt cold patch material.

[0019] Furthermore, the composite bonding system formed in S2 has an initial viscosity range of 800-1200 mPa·s at 25°C, ensuring suitable fluidity during construction and facilitating thorough mixing with aggregates and powders; and the viscosity increase does not exceed 20% within 48 hours, ensuring the storage stability of the bonding system, avoiding premature curing and narrowing the construction window, and reserving sufficient operation time for subsequent mixing with aggregates and powders.

[0020] Furthermore, in step S3, the composite powder is added in three stages: 40% of the total amount in the first stage, 30% in the second stage, and 30% in the third stage. After each addition, the stirring speed is first increased to 1500 rpm and maintained for 3 minutes, then reduced to 1200 rpm and stirred continuously for 7 minutes. This avoids powder agglomeration caused by adding the powder all at once, while ensuring that the powder is in full contact with the binder system and aggregates and is evenly distributed, reducing internal voids in the material and significantly improving mechanical strength and resistance to wear.

[0021] This invention provides a composite asphalt cold patching material and its preparation method, which has the following beneficial effects: 1. This invention utilizes the synergistic design of modified asphalt and modified basalt aggregate to construct a strong and tough composite bonding system, effectively solving the problem of insufficient bonding in traditional cold patch materials. The modified asphalt undergoes multiple modifications, including waste tire rubber powder, nano-montmorillonite, and MDI-type isocyanate, significantly enhancing its molecular structure stability. The modified basalt aggregate is treated with silane coupling agents, an epoxy curing system, and graphene oxide, resulting in a substantial improvement in surface activity and interfacial compatibility. The combination of these two materials ensures a tight bond between the aggregate and the binder, resisting repeated crushing by heavy vehicles and erosion by rainwater. This reduces problems such as patch layer displacement and detachment, ensuring the product maintains a stable structure even under complex road conditions and extending the service life of the repaired area.

[0022] 2. Based on an optimized formulation of early-strength silicate cement, propylenediamine, and epoxy curing agent, the product exhibits excellent early-strength curing performance. At 25℃, it achieves over 80% curing within 24 hours, rapidly developing mechanical strength and significantly shortening traffic restoration time. This avoids the traffic congestion and secondary damage risks associated with the slow curing of traditional cold-applied patches. Furthermore, the product is suitable for room-temperature construction, requiring no large heating equipment, and is easy and flexible to operate. Whether for emergency repairs or routine road surface maintenance, it can efficiently complete the work, improving the timeliness and economy of road repair.

[0023] 3. This invention's product, through the integration of multiple anti-aging components, possesses excellent environmental adaptability and can withstand natural erosion under various climatic conditions. Among them, the UV-531 anti-ultraviolet agent delays asphalt oxidative embrittlement, nano-silica and graphene oxide enhance the material's impermeability and freeze-thaw resistance, and the modified aggregate's quartz sand micro-powder coating further improves wear resistance. Whether subjected to high-temperature exposure, low-temperature freezing, rain immersion, or ultraviolet radiation, the product maintains stable performance, reducing aging problems such as cracking and loosening of the repair layer, and is suitable for the road maintenance needs of different regions.

[0024] 4. While optimizing performance, the product prioritizes environmental protection and resource recycling. By introducing waste tire rubber powder to modify the asphalt, it achieves the recycling of waste resources, reduces solid waste pollution, and enhances the low-temperature crack resistance of the asphalt through the elasticity of the rubber powder. Simultaneously, the aggregate and powder gradation design is reasonable, avoiding material waste and aligning with the trend of green engineering development. Furthermore, the improved long-term durability of the product reduces material consumption and construction waste from frequent maintenance, minimizing environmental impact from a life-cycle perspective and balancing road maintenance effectiveness with sustainable development needs. Detailed Implementation

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1: Preparation of composite asphalt cold patching material. The specific preparation steps are as follows: S1. Pass 27 parts of basalt aggregate and 18 parts of modified basalt aggregate through a 10-mesh sieve, and pass 15 parts of limestone manufactured sand through a 100-mesh sieve. Then put them together in an oven at 105℃ and dry for 2 hours. After cooling to room temperature, mix them evenly to obtain pretreated mixed aggregate. Three parts of early-strength silicate cement, 0.3 parts of nano-silica, 0.2 parts of propylenediamine, and 0.1 parts of UV inhibitor UV-531 were ground through a 200-mesh sieve and mixed evenly to prepare a composite powder. Mix 0.8 parts of epoxy resin E-44 with 0.8 parts of polyamide 650, add 0.3 parts of acetone to dilute, and stir for 10 minutes to prepare an epoxy curing agent system; S2. Take 10 parts of modified asphalt and put it into a reaction vessel. Add 2 parts of diesel oil and stir to adjust the viscosity to 1500 mPa·s at 60℃. Stir at 1000 r / min for 15 min. Add 1 part of SBS modifier and maintain the temperature at 87℃. Shear with a high-speed shear machine at 2500 r / min for 30 min. Then raise the temperature to 100℃ and hold for 10 min. Then lower the temperature to 80℃ and add the prepared epoxy curing agent system. Adjust the stirring speed to 1500 r / min and react for 20 min to form a composite bonding system. Ensure that the curing degree of this system is ≥80% at 25℃ for 24 h. S3. Add the pretreated mixed aggregate to the composite bonding system in the reactor. Reduce the stirring speed to 800 r / min and maintain the temperature at 70℃ for 30 minutes to initially coat the aggregate surface with asphalt binder. Add the composite powder in three batches: 40% of the total amount in the first batch, 30% in the second batch, and 30% in the third batch. After each addition, increase the stirring speed to 1500 r / min and maintain it for 3 minutes, then reduce it to 1200 r / min and continue stirring for 7 minutes. Add the next batch after a 10-minute interval. Control the temperature at 65℃ to ensure uniform dispersion of the powder. Finally, add 0.05 parts of polydimethylsiloxane, adjust the stirring speed to 600 r / min, and continue stirring for 15 minutes to eliminate air bubbles. S4. Close the heating jacket, start the reactor cooling water device, and maintain stirring at 200r / min for maturation. Reduce the material temperature to 45℃ within 20 minutes. During this period, take samples to test the looseness of the material. It is qualified if it can be formed into a ball when squeezed by hand and crumbles when released. S5. After curing, quickly pack the material into moisture-proof woven bags, seal the packaging, and obtain composite asphalt cold patching material.

[0027] Example 2: Preparation of composite asphalt cold patching material. The specific preparation steps are as follows: S1. Pass 33 parts of basalt aggregate and 22 parts of modified basalt aggregate through a 10-mesh sieve, and pass 20 parts of limestone manufactured sand through a 100-mesh sieve. Then put them together in an oven at 105℃ and dry for 2 hours. After cooling to room temperature, mix them evenly to obtain pretreated mixed aggregate. Six parts of early-strength silicate cement, 0.8 parts of nano-silica, 0.5 parts of propylenediamine, and 0.3 parts of UV inhibitor UV-531 were ground through a 200-mesh sieve and mixed evenly to form a composite powder. Mix 1.5 parts of epoxy resin E-44 with 1.5 parts of polyamide 650, add 0.5 parts of acetone to dilute, and stir for 10 minutes to prepare an epoxy curing agent system; S2. Take 15 parts of modified asphalt and put it into a reaction vessel. Add 2.5 parts of diesel oil and stir to adjust the viscosity to 2500 mPa·s at 60℃. Stir at 1000 r / min for 15 min. Add 3 parts of SBS modifier and maintain the temperature at 93℃. Shear with a high-speed shear machine at 2500 r / min for 30 min. Then raise the temperature to 100℃ and hold for 10 min. Then lower the temperature to 80℃ and add the prepared epoxy curing agent system. Adjust the stirring speed to 1500 r / min and react for 20 min to form a composite bonding system. Ensure that the curing degree of this system is ≥80% at 25℃ for 24 h. S3. Add the pretreated mixed aggregate to the composite bonding system in the reactor. Reduce the stirring speed to 800 r / min and maintain the temperature at 80℃ for 30 minutes to initially coat the aggregate surface with asphalt binder. Add the composite powder in three batches: 40% of the total amount in the first batch, 30% in the second batch, and 30% in the third batch. After each addition, increase the stirring speed to 1500 r / min and maintain it for 3 minutes, then reduce it to 1200 r / min and continue stirring for 7 minutes. Add the next batch after a 10-minute interval. Control the temperature at 75℃ to ensure uniform dispersion of the powder. Finally, add 0.15 parts of polydimethylsiloxane, adjust the stirring speed to 600 r / min, and continue stirring for 15 minutes to eliminate air bubbles. S4. Close the heating jacket, start the reactor cooling water device, and maintain stirring at 200r / min for maturation. Reduce the material temperature to 45℃ within 20 minutes. During this period, take samples to test the looseness of the material. It is qualified if it can be formed into a ball when squeezed by hand and crumbles when released. S5. After curing, quickly pack the material into moisture-proof woven bags, seal the packaging, and obtain composite asphalt cold patching material.

[0028] Example 3: Preparation of composite asphalt cold patching material. The specific preparation steps are as follows: S1. Pass 30 parts of basalt aggregate and 20 parts of modified basalt aggregate through a 10-mesh sieve, and pass 17 parts of limestone manufactured sand through a 100-mesh sieve. Then put them together in an oven at 105℃ and dry for 2 hours. After cooling to room temperature, mix them evenly to obtain pretreated mixed aggregate. Four parts of early-strength silicate cement, 0.5 parts of nano silica, 0.3 parts of propylenediamine, and 0.2 parts of UV inhibitor UV-531 were ground through a 200-mesh sieve and mixed evenly to prepare a composite powder. Mix 1 part epoxy resin E-44 with 1 part polyamide 650, add 0.4 parts acetone to dilute, and stir for 10 minutes to prepare an epoxy curing agent system; S2. Take 12 parts of modified asphalt and put it into a reaction vessel. Add 2.2 parts of diesel oil and stir to adjust the viscosity to 2000 mPa·s at 60℃. Stir at 1000 r / min for 15 min. Add 2 parts of SBS modifier and maintain the temperature at 90℃. Shear with a high-speed shear machine at 2500 r / min for 30 min. Then raise the temperature to 100℃ and hold for 10 min. Then lower the temperature to 80℃ and add the prepared epoxy curing agent system. Adjust the stirring speed to 1500 r / min and react for 20 min to form a composite bonding system. Ensure that the curing degree of this system is ≥80% at 25℃ for 24 h. S3. Add the pretreated mixed aggregate to the composite bonding system in the reactor. Reduce the stirring speed to 800 r / min and maintain the temperature at 75℃ for 30 minutes to initially coat the aggregate surface with asphalt binder. Add the composite powder in three batches: 40% of the total amount in the first batch, 30% in the second batch, and 30% in the third batch. After each addition, increase the stirring speed to 1500 r / min and maintain it for 3 minutes, then reduce it to 1200 r / min and continue stirring for 7 minutes. Add the next batch after a 10-minute interval. Control the temperature at 70℃ to ensure uniform dispersion of the powder. Finally, add 0.1 parts of polydimethylsiloxane, adjust the stirring speed to 600 r / min, and continue stirring for 15 minutes to eliminate air bubbles. S4. Close the heating jacket, start the reactor cooling water device, and maintain stirring at 200r / min for maturation. Reduce the material temperature to 45℃ within 20 minutes. During this period, take samples to test the looseness of the material. It is qualified if it can be formed into a ball when squeezed by hand and crumbles when released. S5. After curing, quickly pack the material into moisture-proof woven bags, seal the packaging, and obtain composite asphalt cold patching material.

[0029] Example 4: Preparation of modified asphalt. The specific preparation steps are as follows: A1. Heat 1000g of 70# base asphalt to 160℃, add 400g of waste tire rubber powder that has passed through an 80-mesh sieve, and shear and disperse it using a high-speed shear machine at 3000r / min for 1h, keeping the temperature stable during this period to allow the rubber powder to fully swell; slowly add a mixture of 20ml maleic anhydride and 30ml xylene, raise the temperature to 175℃, and react at a constant temperature for 2h; then lower the temperature to 165℃, add 15ml of diethylenetriamine, and stir to react for 1.5h to obtain the first modified asphalt; A2. Take 1000g of the first modified asphalt, cool it to 140℃, add 30g of nano-montmorillonite, and ultrasonically disperse for 30min; dilute 50ml of styrene-acrylate emulsion with a solid content of 40% with 80ml of deionized water, and slowly spray it into the asphalt system while stirring at a speed of 1500r / min, and maintain the temperature at 140℃ for 1h; then add 10ml of tetrabutyl titanate coupling agent, raise the temperature to 145℃ and react for 1h to obtain the second modified asphalt; A3. Take 1000g of the second modified asphalt and cool it to 120℃. Add a mixture of 25g of polyethylene glycol 400 and 15ml of anhydrous ethanol and stir at 1000r / min for 30min. Use a constant pressure dropping funnel to slowly add 18ml of MDI isocyanate at a dropping rate of 0.3ml / min. Heat to 125℃ and stir for 40min. Then add 8ml of tributyl phosphate and stir at 800r / min for 20min to obtain the modified asphalt.

[0030] Example 5: Preparation of modified asphalt. The specific preparation steps are as follows: A1. Heat 1000g of 70# base asphalt to 170℃, add 500g of waste tire rubber powder that has passed through an 80-mesh sieve, and shear and disperse it using a high-speed shear machine at 3500r / min for 1h, keeping the temperature stable during this period to allow the rubber powder to fully swell; slowly add a mixture of 30ml maleic anhydride and 40ml xylene, raise the temperature to 185℃, and react at a constant temperature for 2h; then lower the temperature to 175℃, add 25ml of diethylenetriamine, and stir to react for 1.5h to obtain the first modified asphalt; A2. Take 1000g of the first modified asphalt, cool it to 150℃, add 40g of nano-montmorillonite, and ultrasonically disperse for 30min; dilute 60ml of styrene-acrylate emulsion with 40% solid content with 100ml of deionized water, and slowly spray it into the asphalt system while stirring at 2000r / min, maintaining the temperature at 150℃ for 1h; then add 15ml of tetrabutyl titanate coupling agent, raise the temperature to 155℃ and react for 1h to obtain the second modified asphalt; A3. Take 1000g of the second modified asphalt and cool it to 130℃. Add a mixture of 35g of polyethylene glycol 400 and 20ml of anhydrous ethanol and stir at 1000r / min for 30min. Use a constant pressure dropping funnel to slowly add 28ml of MDI isocyanate at a dropping rate of 0.5ml / min. Heat to 135℃ and stir for 40min. Then add 12ml of tributyl phosphate and stir at 800r / min for 20min to obtain the modified asphalt.

[0031] Example 6: Preparation of modified basalt aggregate. The specific preparation steps are as follows: B1. Rinse 1000g of basalt aggregate with clean water to remove impurities, dry it in an oven at 105℃ for 2 hours, and cool it to room temperature before placing it in a high-speed mixer. Mix 20ml of silane coupling agent KH-550, 5ml of 1mol / L hydrochloric acid and 100ml of deionized water, and stir for 30 minutes to form a hydrolysate. Spray the hydrolysate onto the surface of the aggregate, start the mixer and stir at 800r / min for 20 minutes, while adding 15g of nano-calcium carbonate and continuing to stir for 20 minutes to obtain the first modified basalt aggregate. B2. Take 1000g of the first modified basalt aggregate and preheat it in an oven at 60℃ for 30min. After taking it out, put it into a mixer. Mix and dilute 30ml of epoxy resin E-51 with 10ml of acetone, add 25ml of polyamide 650 and stir evenly to prepare an epoxy curing system. Spray the epoxy curing system evenly onto the surface of the preheated aggregate. Adjust the mixer speed to 1200r / min and stir for 30min. Then immediately add 15g of quartz sand powder that has passed through a 120-mesh sieve and continue stirring for 20min. Keep it at 80℃ for 1h to complete the curing and obtain the second modified basalt aggregate. B3. Cool 1000g of the second modified basalt aggregate to 40℃ and put it into a mixer. Add 40ml of 5% (w / w) polyvinyl alcohol 1788 aqueous solution and stir at 800r / min for 15min. Then add 10g of 0.5mg / mL graphene oxide dispersion, sonicate at 300W and stir at 1200r / min for 20min. Then add 8ml of propylene glycol and stir at 800r / min for 15min. Finally, let the aggregate air dry to obtain the modified basalt aggregate.

[0032] Example 7: Preparation of modified basalt aggregate. The specific preparation steps are as follows: B1. Rinse 1000g of basalt aggregate with clean water to remove impurities, dry it in an oven at 105℃ for 2 hours, and cool it to room temperature before placing it in a high-speed mixer. Mix 30ml of silane coupling agent KH-550, 8ml of 1mol / L hydrochloric acid and 120ml of deionized water, and stir for 30 minutes to form a hydrolysate. Spray the hydrolysate onto the surface of the aggregate, start the mixer and stir at 1000r / min for 20 minutes, while adding 20g of nano-calcium carbonate and continuing to stir for 20 minutes to obtain the first modified basalt aggregate. B2. Take 1000g of the first modified basalt aggregate and preheat it in an oven at 70℃ for 30min. After taking it out, put it into a mixer. Mix and dilute 40ml of epoxy resin E-51 with 15ml of acetone, add 35ml of polyamide 650 and stir evenly to prepare an epoxy curing system. Spray the epoxy curing system evenly onto the surface of the preheated aggregate. Adjust the mixer speed to 1500r / min and stir for 30min. Then immediately add 25g of quartz sand powder that has passed through a 120-mesh sieve and continue stirring for 20min. Keep it at 90℃ for 1h to complete the curing and obtain the second modified basalt aggregate. B3. Cool 1000g of the second modified basalt aggregate to 50℃ and put it into a mixer. Add 50ml of 5% (w / w) polyvinyl alcohol 1788 aqueous solution and stir at 800r / min for 15min. Then add 15g of 0.5mg / mL graphene oxide dispersion, sonicate at 300W and stir at 1200r / min for 20min. Then add 12ml of propylene glycol and stir at 800r / min for 15min. Finally, let the aggregate air dry to obtain the modified basalt aggregate.

[0033] Comparative Example 1: Preparation of composite asphalt cold patching material. The specific preparation steps are as follows: The remaining steps remain the same, except that the modified asphalt prepared in Example 4 used in Example 3 is replaced with unmodified asphalt to prepare composite asphalt cold patching material.

[0034] Comparative Example 2: Preparation of composite asphalt cold patching material. The specific preparation steps are as follows: The remaining steps remain the same, except that the modified basalt aggregate prepared in Example 7 used in Example 3 is replaced with unmodified basalt aggregate to prepare composite asphalt cold patching material.

[0035] Comparative Example 3: Preparation of composite asphalt cold patching material. The specific preparation steps are as follows: The remaining steps remain the same, except that the modified asphalt prepared in Example 4 used in Example 3 is replaced with unmodified asphalt, and the modified basalt aggregate is replaced with unmodified basalt aggregate to prepare composite asphalt cold patching material.

[0036] Performance testing Test Project Test Standards Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Marshall stability (kN) JTGE20-2011T0709 12.3 14.1 15.6 9.8 10.5 8.2 Splitting bond strength (25℃) (MPa) JTGE20-2011T0716 1.02 1.15 1.28 0.75 0.83 0.52 24-hour curing degree (%) JT / T740-2024 82.5 85.3 88.7 71.2 73.6 60.5 Strength loss rate after freeze-thaw cycles (-18℃~25℃, 10 cycles) (%) JTGE20-2011T0729 8.3 6.7 5.1 15.6 13.2 25.8 Weight loss rate after UV aging (168h UV irradiation) (%) JTGE20-2011T0734 3.2 2.5 2.1 6.8 5.7 8.3 Wear loss (load 4.2kg, 500 rpm) (%) JTGE20-2011T0736 4.8 3.9 3.2 7.5 6.3 10.1 Test results show that the composite asphalt cold patching materials of Examples 1-3 of this invention are superior to the comparative examples 1-3 in all core performance aspects: In terms of mechanical properties, the Marshall stability reaches a maximum of 15.6 kN and the splitting bond strength at 25℃ reaches a maximum of 1.28 MPa, which is significantly higher than the comparative examples without modified asphalt or modified basalt aggregate; in terms of curing efficiency, the degree of curing after 24 hours all exceed 82%, and Example 3 even reaches 88.7%, which is far superior to the 60.5%-73.6% of the comparative examples; the durability performance is outstanding, with the lowest freeze-thaw cycle strength loss rate of only 5.1%, the lowest UV aging mass loss rate of only 2.1%, and the lowest abrasion loss of only 3.2%, which are significantly lower than the corresponding values ​​of the comparative examples. This indicates that the synergistic design of modified asphalt and modified basalt aggregate effectively improves the material's adhesion, curing speed, and anti-aging and anti-loss capabilities, while the comparative examples without modified raw materials have obvious shortcomings in all performance aspects.

[0037] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A composite asphalt cold patch material, characterized by: The modified asphalt comprises the following raw materials by weight: 10-15 parts of modified asphalt, 27-33 parts of basalt aggregate, 18-22 parts of modified basalt aggregate, 15-20 parts of limestone machine-made sand, 3-6 parts of early strength Portland cement, 1-3 parts of styrene-butadiene-styrene block copolymer modifier, 0.8-1.5 parts of epoxy resin E-44, 0.8-1.5 parts of polyamide 650, 0.3-0.8 parts of nano silicon dioxide, 0.2-0.5 parts of propylene diamine, 0.1-0.3 parts of anti-ultraviolet agent UV-531, 0.05-0.15 parts of polydimethylsiloxane, 2-2.5 parts of diesel oil, and 0.3-0.5 parts of acetone. The modified asphalt is prepared by the following steps: A1, heat 70# base asphalt to 160-170 DEG C, add waste tire rubber powder through an 80-mesh sieve, and shear and disperse by using a high-speed shearing machine at a speed of 3000-3500 r / min for 1 h, during which the temperature is kept stable, so that the rubber powder is fully swollen; slowly add a mixed solution of maleic anhydride and dimethylbenzene, heat to 175-185 DEG C, and keep constant temperature for 2 h; then, cool to 165-175 DEG C, add diethylenetriamine, and stir for 1.5 h to obtain first modified asphalt; A2, take the first modified asphalt, cool to 140-150 DEG C, add nano montmorillonite, and ultrasonically disperse for 30 min; dilute styrene-acrylate emulsion with a solid content of 40% in deionized water, slowly spray into the asphalt system, and stir at a speed of 1500-2000 r / min, keep the temperature at 140-150 DEG C, and react for 1 h; then, add tetrabutyl titanate coupling agent, heat to 145-155 DEG C, and react for 1 h to obtain second modified asphalt; A3, take the second modified asphalt, cool to 120-130 DEG C, add a mixed solution of polyethylene glycol 400 and anhydrous ethanol, and stir at 1000 r / min for 30 min; slowly add MDI type isocyanate, heat to 125-135 DEG C, and stir for 40 min; then, add tributyl phosphate, and stir at 800 r / min for 20 min to obtain modified asphalt; The modified basalt aggregate is prepared by the following steps: B1, wash the basalt aggregate with clean water to remove impurities, put it into an oven at 105 DEG C for drying for 2 h, cool to room temperature, and then put it into a high-speed stirrer; mix silane coupling agent KH-550, concentrated hydrochloric acid with a concentration of 1 mol / L, and deionized water to form a hydrolysis solution by stirring for 30 min; spray the hydrolysis solution onto the surface of the aggregate, start the stirrer to stir at a speed of 800-1000 r / min for 20 min, and continuously stir for 20 min while adding nano calcium carbonate to obtain first modified basalt aggregate; B2, the first modified basalt aggregate is taken out from the oven and preheated at 60-70℃ for 30 min, and then put into a blender; the epoxy resin E-51 is mixed with acetone, diluted, and then polyamide 650 is added and stirred uniformly to form an epoxy curing system; the epoxy curing system is uniformly sprayed onto the surface of the preheated aggregate, the stirring speed of the blender is adjusted to 1200-1500r / min, and stirring is performed for 30 min, then quartz sand powder sieved through a 120 mesh sieve is immediately added, and stirring is continued for 20 min, and then curing is completed by keeping the temperature at 80-90℃ for 1 h, thereby obtaining the second modified basalt aggregate; B3, the second modified basalt aggregate is cooled to 40-50℃ and put into a blender, 5% polyvinyl alcohol 1788 aqueous solution by mass fraction is added, and stirring is performed at 800r / min for 15 min; then a graphene oxide dispersion liquid with a concentration of 0.5mg / mL is added, and ultrasonic treatment is performed at 300W and stirring is performed at 1200r / min for 20 min; then propylene glycol is added, and stirring is performed at 800r / min for 15 min, and finally the aggregate is naturally air-dried to obtain the modified basalt aggregate.

2. The composite asphalt cold patch material of claim 1, wherein: The early-strength Portland cement has a strength grade of 42.5R, a specific surface area of ≥350 m 2 / kg, an initial setting time of ≥45 min, and a final setting time of ≤6 h.

3. The composite asphalt cold patch material of claim 1, wherein: The NCO content of the MDI type isocyanate in A3 is 29%-31%, a constant pressure dropping funnel is used for adding, the dropping speed is controlled at 0.3-0.5ml / min, and the stirring speed is kept stable during the dropping process.

4. The composite asphalt cold patch material of claim 1, wherein: The amount ratio of 70# base asphalt, waste tire rubber powder, maleic anhydride, dimethylbenzene, and diethylenetriamine in A1 is 1000g:400-500g:20-30ml:30-40ml:15-25ml; The amount ratio of the first modified asphalt, nano-montmorillonite, styrene-acrylate emulsion, deionized water, and titanium tetrabutoxide coupling agent in A2 is 1000g:30-40g:50-60ml:80-100ml:10-15ml; The amount ratio of the second modified asphalt, polyethylene glycol 400, anhydrous ethanol, MDI type isocyanate, and tributyl phosphate in A3 is 1000g:25-35g:15-20ml:18-28ml:8-12ml.

5. The composite asphalt cold patch material of claim 1, wherein: The amount ratio of basalt aggregate, silane coupling agent KH-550, hydrochloric acid, deionized water, and nano-calcium carbonate in B1 is 1000g:20-30ml:5-8ml:100-120ml:15-20g; The amount ratio of the first modified basalt aggregate, epoxy resin E-51, acetone, polyamide 650, and quartz sand powder in B2 is 1000g:30-40ml:10-15ml:25-35ml:15-25g; The amount ratio of the second modified basalt aggregate, polyvinyl alcohol 1788 aqueous solution, graphene oxide dispersion liquid, and propylene glycol in B3 is 1000g:40-50ml:10-15g:8-12ml.

6. A method of preparing the composite asphalt cold patch material of claim 1, characterized by: Specifically comprising the following steps: S1, 27-33 parts of basalt aggregate, 18-22 parts of modified basalt aggregate, 15-20 parts of limestone machine-made sand were respectively passed through a 10-mesh sieve, then were put into a 105℃ oven and dried for 2h, and were mixed uniformly after being cooled to room temperature to obtain pretreated mixed aggregate; 3-6 parts of early strength Portland cement, 0.3-0.8 parts of nano silicon dioxide, 0.2-0.5 parts of propylene diamine, and 0.1-0.3 parts of anti-ultraviolet agent UV-531 were respectively ground through a 200-mesh sieve, and were mixed uniformly to prepare a composite powder; 0.8-1.5 parts of epoxy resin E-44 and 0.8-1.5 parts of polyamide 650 were mixed, 0.3-0.5 parts of acetone was added for dilution, and stirring was performed for 10 min to prepare an epoxy curing agent system; S2, 10-15 parts of modified asphalt were put into a reaction kettle, 2-2.5 parts of diesel oil was added, the viscosity was adjusted to 1500-2500 mPa·s at 60℃, stirring was performed at a speed of 1000 r / min for 15 min, 1-3 parts of styrene-butadiene-styrene block copolymer modifier was added, the temperature was kept at 87-93℃, a high-speed shearing machine was used for shearing at a speed of 2500 r / min for 30 min, and then the temperature was increased to 100℃ and kept for 10 min; The temperature was then decreased to 80℃, the prepared epoxy curing agent system was added, the stirring speed was adjusted to 1500 r / min, and reaction was performed for 20 min to form a composite bonding system, and the curing degree of the system was ensured to be ≥80% at 25℃ for 24 h; S3, the pretreated mixed aggregate was added to the composite bonding system in the reaction kettle, the stirring speed was reduced to 800 r / min, the temperature was kept at 70-80℃, and stirring was performed for 30 min to preliminarily coat the aggregate surface with asphalt binder; the composite powder was added in three times, each time interval was 10 min, the next time was added, the temperature was controlled at 65-75℃, and the powder was uniformly dispersed; finally, 0.05-0.15 parts of polydimethylsiloxane was added, the stirring speed was adjusted to 600 r / min, and stirring was continued for 15 min to eliminate bubbles; S4, the heating jacket was closed, the cooling water device of the reaction kettle was started, and aging was performed at a stirring speed of 200 r / min, and the material temperature was decreased to 45℃ within 20 min; the material loose degree was detected during the period, and the material was qualified when it was held together and scattered when the hand was released; S5, after aging was completed, the material was quickly packed into a moisture-proof woven bag, and was sealed and packaged to obtain a composite asphalt cold patching material.

7. The method for preparing a composite asphalt cold patching material according to claim 6, characterized in that: The initial viscosity of the composite bonding system formed in S2 was in the range of 800-1200 mPa·s at 25℃, and the viscosity growth was not more than 20% within 48 h.

8. The method for preparing a composite asphalt cold patching material according to claim 6, characterized in that: In S3, the composite powder was added in three times, the first time was 40% of the total amount, the second time was 30%, and the third time was 30%, the stirring speed was first increased to 1500 r / min for 3 min after each addition, and then was reduced to 1200 r / min for continuous stirring for 7 min.