Water resistant epoxy resin based emulsified asphalt mixture and method of making and testing

Abstract

The present application belongs to the technical field of emulsified asphalt material, and particularly relates to water-resistant emulsified asphalt mixture based on epoxy resin and its preparation and test method, which comprises the following components in parts by weight: 90-95 parts of aggregate, 3-5 parts of early strength agent, 1-2 parts of water, 2-3 parts of mineral powder and 10-15 parts of modified emulsified asphalt; the modified emulsified asphalt comprises the following components in parts by weight: 45-55 parts of modified asphalt, 3-8 parts of emulsifier, 20-25 parts of epoxy resin and 15-22 parts of water; the modified asphalt comprises the following components in parts by weight: 80-100 parts of base asphalt, 3-5 parts of SBR, 2-5 parts of petroleum resin, 1-2 parts of toughening agent and 5-10 parts of composite curing agent. Through step-by-step preparation, the mixture has good low-temperature toughness and mechanical properties, and can improve the water resistance of the material, so that it can be applied to the surface layer of asphalt pavement, and the application scenarios of the emulsified asphalt mixture are widened.

Description

Technical Field

[0001] This invention belongs to the field of emulsified asphalt material technology, specifically relating to epoxy resin-based water-resistant emulsified asphalt mixtures and their preparation and testing methods. Background Technology

[0002] Currently, hot-mix asphalt mixtures are widely used on asphalt roads in China. These mixtures are made by heating asphalt (modified asphalt) to 165–170°C and then heating aggregate to 190–220°C, mixing them in a mixing plant according to a specific ratio. After long-distance transportation, hot-mix asphalt mixtures require a paving temperature of no less than 160°C and a compaction temperature of no less than 150°C. This traditional asphalt pavement construction material and process, characterized by high energy consumption and high carbon emissions, is gradually becoming incompatible with the current needs of my country's highway transportation. Therefore, developing an energy-saving, carbon-reducing, and environmentally friendly high-performance asphalt road construction technology is a new challenge facing my country's highway transportation system.

[0003] To address the aforementioned issues, developing energy-saving and carbon-reducing "emulsified asphalt mixture" technology has become an option. This technology eliminates the need to heat the aggregate and asphalt, allowing for construction at room temperature. On-site mixing, paving, and compaction enable traffic to resume within 3-5 hours. Furthermore, because emulsified asphalt is not subjected to high-temperature hot mixing and paving, thermal aging is reduced, extending the service life of the asphalt.

[0004] In the prior art, such as Chinese Patent Publication No. CN111099855A, an emulsified asphalt mixture and its preparation method are provided, including aggregates, asphalt, water-based acrylic acid, emulsifier, stabilizer, pH adjuster, curing agent and water. By adjusting the water-based acrylic acid, stabilizer and curing agent, the demulsification speed and molding speed of the mixture can be improved.

[0005] For example, Chinese patent CN105418041A discloses an emulsified asphalt mixture and its preparation method, comprising 4-8 parts by weight of emulsified asphalt, 2-15 parts by weight of added water, 85-95 parts by weight of aggregate, and 0-6 parts by weight of filler. By adding fibers and plasticizers to the cement-added emulsified asphalt mixture, the flexibility of the cement emulsified asphalt mixture is improved, while meeting the requirements for rapid road opening. In addition, the amphoteric oxides, cement, fibers, and plasticizers in the emulsified asphalt mixture can ensure rapid road opening while also taking into account pavement strength, flexibility, and resistance to water damage.

[0006] However, the emulsified asphalt mixtures prepared using the aforementioned existing technologies still have the following problems: Existing water-resistant emulsified asphalt mixtures can only be used in base courses. When used in surface courses, they have the following problems: 1. Low-temperature toughness and mechanical properties cannot be balanced, making them unsuitable for use in areas with large temperature variations; 2. Poor water resistance, especially during the initial laying stage when encountering rainwater impact, resulting in severe secondary emulsification. Summary of the Invention

[0007] To address the aforementioned problems with current emulsified asphalt mixtures, this invention provides an epoxy resin-based water-resistant emulsified asphalt mixture and its preparation and testing methods, which can be applied to the surface layer of asphalt pavements. The specific technical solution is as follows: Firstly, this invention provides a water-resistant emulsified asphalt mixture based on epoxy resin. The mixture comprises the following components by weight: 90-95 parts aggregate, 3-5 parts early-strength agent, 1-2 parts water, 2-3 parts mineral powder, and 10-15 parts modified emulsified asphalt. The modified emulsified asphalt comprises the following components by weight: 45-55 parts modified asphalt, 3-8 parts emulsifier, 20-25 parts epoxy resin, and 15-22 parts water. The modified asphalt comprises the following components by weight: 80-100 parts base asphalt, 3-5 parts SBR, 2-5 parts petroleum resin, 1-2 parts toughening agent, and 5-10 parts composite curing agent.

[0008] Inventive Concept: Through long-term practical work, the inventors discovered that existing research on epoxy resin-modified emulsified asphalt and its mixtures focuses on the modifying components and their interaction with asphalt, such as adding elastomers like SBR / SBS or polyurethane elastomers to improve the poor low-temperature toughness of epoxy resin-modified emulsified asphalt and its mixtures. The inventors have also conducted numerous related attempts, finding no significant difference in performance and effect compared to existing technologies. Based on this, the inventors have taken a different approach, innovatively using curing agents and emulsifiers in the modified emulsification process. By employing compounding schemes, they have been able to solve the low-temperature toughness problem of existing epoxy resin-modified emulsified asphalt and its mixtures while maintaining good mechanical strength. Further use and research on modified emulsified asphalt and its mixtures have revealed that mixtures prepared under various compounding schemes exhibit significantly improved water resistance, preventing phenomena such as emulsification and collapse under rain impact.

[0009] Furthermore, the composite curing agent comprises the following components by weight fraction: 55-65% polyoxypropylene diamine curing agent and 35-45% phenolic amine curing agent. Furthermore, the emulsifier comprises a cationic emulsifier and a nonionic emulsifier, wherein the mass ratio of the cationic emulsifier to the nonionic emulsifier is 1-3:1; the cationic emulsifier is a quaternary ammonium salt emulsifier, and the nonionic emulsifier is an alkyl glycoside emulsifier.

[0010] Furthermore, the early strength agent comprises the following components by mass fraction: 50% quick-setting cement, 30% silicate cement, 13% interface agent, 2% expansion agent, 1.5% accelerator, 2% retarder and 1.5% anti-caking agent.

[0011] Furthermore, the aggregate includes coarse aggregate and fine aggregate, wherein the mass ratio of coarse aggregate to fine aggregate is 1 to 4:1. The aggregate particle size ranges from 2.36 to 9.5 mm, and the fine aggregate particle size ranges from ≤2.36 mm; the aggregate surface is coated with a silane coupling agent, which includes 20-30% titanate coupling agent and 70-80% isooctyltriethoxysilane, and the amount of silane coupling agent used is 0.2-0.3% of the aggregate weight.

[0012] Furthermore, the toughening agent is an acrylic polymer, including polybutylene acrylate and epoxy resin. One or two of the acrylate copolymers. The addition of polybutyl acrylate and epoxy acrylate copolymers in this invention can lower the glass transition temperature of the epoxy resin, accelerate the reaction rate, and provide better low-temperature performance and impact resistance for the mixture.

[0013] This invention also provides a method for preparing an epoxy resin-based water-resistant emulsified asphalt mixture, comprising the following steps: S1 Preparation of Modified Asphalt: After heating the base asphalt, SBR, petroleum resin and curing agent are added to it, and after swelling and shearing, modified asphalt is obtained. S2 Preparation of Modified Emulsified Asphalt: The emulsifier is dissolved in water to make an emulsifier aqueous solution. The modified asphalt is then heated and pumped together with the emulsifier aqueous solution and epoxy resin into a mixing device for emulsification to obtain modified emulsified asphalt. S3 Preparation of Mixture: Preheat the aggregate in the mixing device, spray the aggregate with silane coupling agent solution, add early strength agent and mix evenly, then add emulsified asphalt and mix quickly and evenly to obtain the mixture.

[0014] Furthermore, in step S1, the heating temperature of the base asphalt is 140-145℃, the heating temperature is 175-180℃, the stirring time is 10-15 min, the swelling time is 30-45 min, the shearing time is 120-150 min, and the development time is 90-120 min.

[0015] Furthermore, in step S2, the hot water temperature is 55-60°C, the pH value of the emulsifier aqueous solution is 1.5-3, and the heating temperature of the modified asphalt is 175-180°C.

[0016] This invention also provides a test method for water-resistant emulsified asphalt mixtures based on epoxy resin, comprising the following steps: Step 1: Prepare the test specimen; Step 2: Conduct ultraviolet weathering aging tests on the test specimens. Use ultraviolet lamps to simulate the effect of sunlight exposure and use condensation moisture to simulate rain and dew. Place the test specimens in a cyclic program at -20 to 40°C for 24 hours. Step 3: Immerse the test specimens from Step 2 into a container filled with water. After 15 minutes, remove the specimens and place them in an inclined container. Rinse the specimens with a shower head for 15-20 minutes, and use a container to collect the rinsed water at the bottom. After rinsing, calculate the solubility and turbidity.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1) This invention uses SBR and petroleum resin composite modified matrix asphalt. Compared with conventionally used SBS or SBS+rubber powder modified asphalt, the addition of petroleum resin and its interfacial film-forming properties can enhance the tensile strength of the asphalt and aggregate, thus improving the performance of the modified asphalt. Furthermore, the use of these three materials in the composite modified matrix asphalt, along with the interaction between them and the early-strength agent, enables the emulsified asphalt mixture to achieve or even exceed the performance indicators of hot-mix asphalt mixtures, significantly expanding the application range and usability scenarios of emulsified asphalt mixtures.

[0018] 2) This invention innovatively utilizes curing agents and emulsifiers in the modified emulsification process. The compounding scheme addresses the low-temperature toughness issue of existing epoxy resin-modified emulsified asphalt and its mixtures, while maintaining good mechanical strength. Further application and research on modified emulsified asphalt and its mixtures revealed that mixtures prepared under various compounding schemes exhibit significantly improved water resistance, making them particularly suitable for rainy areas with large temperature differences.

[0019] 3) This invention proposes a test method for water-resistant emulsified asphalt mixture based on epoxy resin. Compared with the current standards or test methods, this method, after aging test of the test specimens, simulates rain erosion, which can best reflect the water resistance performance of the mixture, and provides a new test method. Attached Figure Description

[0020] Figure 1 This is a physical image of the epoxy resin-based water-resistant emulsified asphalt mixture in Embodiment 1 of the present invention; Figure 2 This is a graph showing the test results in Experiment Example 1 of the present invention; Figure 3 This is a graph showing the test results in Experiment Example 1 of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with embodiments.

[0022] This invention provides a method for preparing a water-resistant emulsified asphalt mixture based on epoxy resin, specifically including the following steps: S1 Preparation of Modified Asphalt: After heating the base asphalt, SBR, petroleum resin and curing agent are added to it, and after swelling and shearing, modified asphalt is obtained. Specifically, the base asphalt is heated to 140-145℃, SBR and petroleum resin are added, and the temperature is raised to 175-180℃. After swelling for 30-45 minutes, it is sheared at 3000-5000 rpm for 90-120 minutes, then a composite curing agent is added, and shearing continues for another 30 minutes. Finally, it is developed under the action of a stirrer for 90-120 minutes to obtain modified asphalt. In this invention, commercially available base asphalt, such as Sinopec AH-70, is used. SBR and petroleum resin are purchased from commercial products and have no special requirements. In this invention, the addition of SBR and petroleum resin to modify the base asphalt can improve the low-temperature toughness of the asphalt, enhance the interfacial strength between the asphalt and aggregate in the mixture, and reduce the water penetration capacity. The composite curing agent of this invention includes a polyoxypropylene diamine curing agent and a phenolic amine curing agent, wherein the content of the polyoxypropylene diamine curing agent is 55-65%, and the content of the phenolic amine curing agent is 35-45%. In this invention, the polyoxypropylene diamine curing agent can be the JEFFAMINE D-230 series curing agent, and the phenolic amine curing agent can be the T-31 series epoxy resin curing agent. This invention uses a composite curing agent component, leveraging the rapid curing characteristic of the polyoxypropylene diamine curing agent to avoid excessive moisture intrusion at the interface during the initial solidification stage, while the phenolic amine curing agent enables deep curing. The combination of these two curing agents not only enables rapid curing of the epoxy resin, shortening the traffic opening time, but also ensures the cured strength and guarantees the strength performance of the mixture.

[0023] S2 Preparation of Modified Emulsified Asphalt: The emulsifier is dissolved in water to make an emulsifier aqueous solution. The modified asphalt is then heated and pumped together with the emulsifier aqueous solution and epoxy resin into a mixing device for emulsification to obtain modified emulsified asphalt. Specifically, after weighing the emulsifier according to the specified ratio, it is added to water at 55-60°C and stirred thoroughly to dissolve. The prepared modified asphalt is then heated to 175-180°C and pumped together with the emulsifier aqueous solution and epoxy resin into a colloid mill for emulsification to obtain modified emulsified asphalt. It should be noted that the emulsifier in this invention includes cationic and nonionic emulsifiers, with a mass ratio of cationic to nonionic emulsifier of 2-3:1. When adding the emulsifier, the cationic emulsifier is added first, and the mixture is stirred for 20 minutes, followed by the addition of the nonionic emulsifier and stirring for another 20 minutes.

[0024] In this invention, the cationic emulsifier is a quaternary ammonium salt emulsifier, such as hexadecyltrimethylammonium oxide, a single long-chain quaternary ammonium salt, to avoid steric hindrance conflict caused by double long chains after emulsification, which would damage the emulsification effect. The nonionic emulsifier is an alkyl glycoside emulsifier, limited to an HLB value of 8-10, to facilitate mixing with asphalt. Specific products such as APG-0810, APG-0814, or APG-1214 are all acceptable. The use of both cationic and nonionic emulsifiers in this invention improves the emulsification effect of epoxy resin, SBR, and petroleum resin, ensuring that the modified components are fully emulsified and combined with the base asphalt, preventing demulsification and improving the stability of the emulsified modified asphalt. Simultaneously, the two-component emulsifier improves the waterproof performance of the emulsified asphalt. The cationic emulsifier reduces water adsorption by changing the charge at the aggregate-asphalt interface, while the nonionic emulsifier, through its hydrophobic long chains, prevents water penetration. The properties of the modified emulsified asphalt prepared above are shown in Table 1 below: Table 1 Performance of Modified Emulsified Asphalt In this invention, the transport and mechanical stability of modified emulsified asphalt refers to its stability under mechanical impact during mixing, flow, transport, and pumping.

[0025] The experimental results show that the modified emulsified asphalt prepared using this invention exhibits a significant improvement in transportation and mechanical stability compared to existing technologies. After 4-6 hours of transportation, the residual amount on the sieve is ≤0.05, greatly enhancing the stability of the modified emulsified asphalt during transportation and preventing demulsification and flocculation. Furthermore, the softening point of the emulsified asphalt can be selectively customized based on the amount of emulsifier and modifier used to meet different application requirements. When the amount of modifier and the ratio of modified emulsified asphalt in the modified asphalt are changed, the transportation and mechanical stability of the prepared modified emulsified asphalt deteriorates significantly, leading to a significant increase in the residual amount on the sieve, obvious demulsification, and significant flocculation during transportation.

[0026] S3 Preparation of Mixture: Preheat the aggregate in the mixing device, spray the aggregate with silane coupling agent solution, add early strength agent and mix evenly, then add emulsified asphalt and mix quickly and evenly to obtain the mixture.

[0027] Specifically, aggregates, including coarse and fine aggregates, are added to the mixing device. The coarse aggregates should be hard, rough, and angular in appearance, and their technical requirements should comply with the "Technical Specifications for Construction of Highway Asphalt Pavement." The fine aggregates should be clean, dry, unweathered, and free of impurities. After the coarse and fine aggregates are mixed in the correct proportions, they are placed in the mixing device for preheating and drying. After drying, a silane coupling agent solution is sprayed onto the aggregates to allow the silane coupling agent to adhere to them. In this invention, the silane coupling agent includes isooctyltriethoxysilane, etc. After spraying, an early-strength agent is added to the aggregates and mixed evenly. Then, modified emulsified asphalt is added and mixed evenly. Water is then poured in and quickly mixed to ensure a uniform mixture. After even mixing, mineral powder is added in a dry state and mixed thoroughly. The early-strength agent used in this invention is composed of 50% quick-setting cement, 30% silicate cement, 13% interface agent, 2% expansion agent, 1.5% accelerator, 2% retarder, and 1.5% anti-caking agent. The mineral powder used in this invention is talc or mica powder, with a particle size of 5–15 μm. It should be noted that the talc or mica powder in this invention has a flaky structure. By setting the filler shape, the filler can be more easily filled into the gaps in the aggregate, thereby forming a denser structure and effectively reducing the permeability coefficient.

[0028] In this invention, the components of the emulsified asphalt mixture are in the following weight proportions: 95-98 parts aggregate, 3-5 parts early strength agent, 1-2 parts water, 2-3 parts mineral powder, and 10-15 parts modified emulsified asphalt.

[0029] Experimental Example 1: The Influence of Modifying Components on the Properties of Modified Emulsified Asphalt Experimental objective: To verify the effects of modified components and other ingredients on the properties of modified emulsified asphalt. Experimental Methods: Following the preparation method described above, experimental and control groups were set up to compare the effects of different modified components and combinations of modified components on the properties of modified emulsified asphalt. The component differences between the experimental and control groups are shown in Table 2 below, and the performance tests of the modified emulsified asphalt are also shown in Table 3 below. Table 2. Distribution ratio of modified emulsified asphalt in experimental and control groups serial number Modified components curing agent emulsifier toughening agent experimental group WER+SBR+HR PD+PA CE+NE PBA+EAC Comparison Group 1 WER+SBR PD+PA CE+NE PBA+EAC Comparison Group 2 WER PD+PA CE+NE PBA+EAC Comparison Group 3 WER+SBR+HR PD CE+NE PBA+EAC Comparison Group 4 WER+SBR+HR PA CE+NE PBA+EAC Comparison Group 5 WER+SBR+HR PD+PA CE PBA+EAC Comparison Group 6 WER+SBR+HR PD+PA NE PBA+EAC Comparison Group 7 WER+SBR+HR PD+PA CE+NE / Table 3 Performance of Modified Emulsified Asphalt in Experimental and Control Groups serial number Glass transition temperature (°C) Tensile strength (MPa) Elongation at break (%) Shear strength (MPa) experimental group -3.6 3.1 103.4 1.9 Comparison Group 1 -5.1 2 124.2 0.9 Comparison Group 2 10.5 0.5 214.7 0.1 Comparison Group 3 -4.1 1.6 128.3 0.8 Comparison Group 4 -1.3 3.9 64.5 2.4 Comparison Group 5 -2.3 3.3 89.4 1.6 Comparison Group 6 -3.7 2.4 111.9 1.3 Comparison Group 7 0.4 2.6 58.1 1.7 Analysis of experimental results: This invention presents a detailed comparative study of the modifying components, curing agents, emulsifiers, and toughening agents in modified emulsified asphalt. Addressing the current problems in research on epoxy resin-based modified emulsified asphalt, this invention, through the compounding of multiple components in specific proportions and incorporation sequences, can balance the mechanical strength, toughness, and low-temperature performance of modified emulsified asphalt, enabling epoxy resin-based modified emulsified asphalt to have a wider range of applications.

[0030] Data from comparative groups 1 and 2 show that by adding SBR and petroleum resin, SBR improves the low-temperature toughness and deformation resistance of emulsified asphalt, while petroleum resin improves its strength and high-temperature stability. This compound modification significantly broadens the application range of emulsified asphalt, making it suitable for both low-temperature and high-temperature environments and exhibiting significant enhancements in strength and toughness.

[0031] Data from comparison groups 3 and 4 show that the dual-curing agent system ensures a balance in various properties of the modified emulsified asphalt. In particular, compared to using a single curing agent such as phenolic amine curing agent, the loss in low-temperature ductility is significant, severely limiting the service life of current epoxy resin-modified emulsified asphalt in low-temperature environments.

[0032] Data from comparative groups 5 and 6 show that using a dual emulsifier component significantly improves the tensile and shear strength of modified emulsified asphalt without significantly sacrificing its low-temperature performance. This is because cationic emulsifiers enhance the strength properties of emulsified asphalt by altering its charge, while nonionic emulsifiers, with their long organic chains, enhance the ductility of emulsified asphalt without affecting its strength.

[0033] Data from comparison group 7 shows that, compared to existing technologies that often use rubber elastomers such as SBR or SBS as toughening agents, the technical solution of this invention goes a step further by adding PBA and EAC as toughening agents. Experiments have demonstrated that these two materials, even at low addition levels, can significantly enhance the strength and low-temperature toughness of the modified emulsified asphalt, especially its low-temperature toughness. This is because these two materials, under the action of the emulsifier, can achieve good compatibility and bonding with epoxy resin, and their excellent low-temperature toughness further improves the material's properties.

[0034] Furthermore, this experimental example further investigated the proportions of the above-mentioned compound components, and the results are shown in the appendix. Figure 2 and 3 As shown, the attached Figure 2 The middle section shows a line graph of the mass ratio of polyoxypropylene diamine to phenolic amine in the curing agent versus the tensile strength and elongation at break of the modified emulsified asphalt. (Attached) Figure 3This is a line graph showing the relationship between the mass ratio of cationic to nonionic emulsifiers in the emulsifier and the tensile strength and elongation at break of the modified emulsified asphalt. (See attached...) Figure 2 It can be seen from the data that when the mass ratio of polyoxypropylene diamine to phenolic amine is between 65:35 and 55:45, a balance is achieved between toughness and mechanical strength. (From the attached...) Figure 3 It can be seen that the balance between toughness and mechanical strength is achieved when the mass ratio of cationic emulsifier to nonionic emulsifier is between 1 and 3:1.

[0035] Experiment Example 2: Asphalt Mixture Road Performance Test Experimental objective: To verify the road performance of epoxy resin-based water-resistant emulsified asphalt mixture.

[0036] Experimental method: In accordance with the JTG E20-2011 experimental procedure, experimental groups and control groups were set up to prepare water-resistant emulsified asphalt mixture test specimens and test their Marshall stability, low temperature stability and high temperature stability. Among them, the experimental group is the water-resistant emulsified asphalt mixture prepared according to the method in the example, and the control group includes control group 8 without silane coupling agent sprayed in the aggregate, control group 9 without early strength agent added, and control group 10, control group 11 and control group 12 water-resistant emulsified asphalt mixtures prepared according to the modified emulsified asphalt prepared according to control group 1, control group 3 and control group 6 in Experimental Example 1. The steps for making Marshall standard test specimens are as follows: (1) Weigh 1200g of aggregate according to the gradation AC-13 requirements and add it to the mixing basin, add early strength agent and mix evenly; (2) Pour in water and mix evenly; (3) Add emulsified asphalt and mix for 1min. (4) After mixing, the thick emulsified asphalt slurry fully coats the stone and does not flow, and the aggregate is semi-loose. (5) After the specimen is compacted, immediately use tweezers to remove the release paper underneath and start demolding. After demolding, immediately use tweezers to remove the release paper on top. Remove the specimen and place it indoors or outdoors. (6) Depending on the required placement time, the Marshall stability test of the mixture can be performed, such as 3 hours, 4 hours, 5 hours, 22 days, etc. Before determining the stability and flow value, measure the height of the specimen to ensure that the height meets 63.5mm±1.3mm (standard specimen); when the specimen is placed outdoors and the temperature of the specimen to be tested is higher than the indoor temperature, the specimen should be restored to room temperature before the Marshall stability test is performed. (7) If the test time is too tight and the relevant test conditions (such as residual stability, etc.) require natural placement for 22 days, the prepared Marshall specimen can also be placed in an oven at 60℃ and dried to constant weight. The test results are shown in Table 4 below: Table 4. Test Results of Asphalt Mixture Road Performance serial number Marshall stability (KN) Freeze-thaw splitting strength ratio (%) Dynamic stability at 60℃ (cycles / mm) Maximum bending strain (με) at -10℃ experimental group 21.35 95.2 18540 5254 Comparison Group 8 12.81 68.3 4405 2175 Comparison Group 9 15.11 86.3 2818 2691 Control group 10 15.47 82.6 5596 4307 Comparison Group 11 14.35 78.9 4520 3678 Control group 12 16.05 83.1 5747 4512 Analysis of experimental results: Based on Experiment 1, this invention further prepared emulsified asphalt mixture and tested its key road performance indicators, including Marshall stability, low-temperature stability, and high-temperature stability.

[0037] In comparison group 8, no silane coupling agent was sprayed on the aggregates during the preparation process. The experimental results show a significant decrease in all performance parameters of the mixture. This is because various organic materials, such as curing agents, emulsifiers, various modifiers, and toughening agents, were used in the emulsified asphalt stage of this invention. When these materials are mixed with the aggregates, uneven mixing and demulsification are very likely to occur. This is especially true for epoxy resin-based modified emulsified asphalt. Improving the compatibility between epoxy resin and aggregates and avoiding agglomeration has always been a very important research direction. Therefore, this invention treats the aggregates before mixing by spraying a silane coupling agent onto the dried aggregates. One end of the silane coupling agent bonds with the silica on the aggregate surface to form a covalent bond, while the other end bonds with the organic components in the modified emulsified asphalt.

[0038] No petroleum resin was added to the mixture in Comparative Example 10. In this invention, petroleum resin can improve the high-temperature stability of the mixture, and its addition amount is crucial. If too much petroleum resin is added, it can easily lead to phase separation in the mixture, causing demulsification.

[0039] In Comparative Example 11, only conventional polyetheramine curing agents were used. Polyetheramine curing agents have good compatibility with asphalt and are suitable for use in mixtures in low-temperature and cold regions. However, the mixture cured with polyetheramine curing agents has poor rigidity and weak load-bearing capacity. The comparison shows that adding a portion of phenolic amine curing agents, which react more slowly with epoxy resin, allows for deeper curing and improves the stability of the mixture.

[0040] Experiment Example 3: Water Resistance Test of Asphalt Mixture Experimental Objective: To verify the water resistance of epoxy resin-based water-resistant emulsified asphalt mixtures. Experimental Method: Following the experimental and control group setup in Example 3, test specimens were prepared according to the method specified in JTGE20-2011. The test specimens were circular, with a diameter of 101.6 mm ± 0.2 mm and a height of 63.5 mm ± 1.3 mm. After 5 hours of natural placement, the specimens were tested using the following method: The specimens were placed in an ultraviolet weathering test chamber. Ultraviolet lamps simulated sunlight exposure, and condensation simulated rain and dew. The specimens were subjected to alternating cycles of light and moisture at temperatures ranging from -20°C to 40°C for 24 hours. After the test, the specimens were immersed in a container of clean water, with the water level approximately 2-3 cm below the top. After 15 minutes, the specimens were removed and placed in an inclined container. The specimens were then rinsed with a showerhead for 15 minutes, with the bottom of the container collecting the rinsed water.

[0041] After rinsing, the turbidity in the container was scored, and the solubility of the test specimen was calculated. The turbidity score in the container ranged from 1 to 5, with higher scores indicating greater turbidity. The solubility of the test specimen was calculated as (weight of the test specimen before testing - weight of the test specimen after testing) / weight of the test specimen before testing × 100%. The test results are shown in Table 5 below. Table 5. Test Results of Water Resistance of Asphalt Mixtures serial number Solubility (%) Turbidity experimental group 2.1 1 Comparison Group 8 9.4 5 Comparison Group 9 10.6 5 Control group 10 5.2 3 Comparison Group 11 4.9 3 Control group 12 6.5 4 Analysis of Experimental Results: The experimental results show that the emulsified asphalt mixture prepared in this application exhibits excellent water resistance. After testing using the methods described in this application, the emulsified asphalt mixture prepared in this application showed virtually no loss, and the test specimens did not undergo secondary deemulsification in water. In contrast, other emulsified asphalt mixtures prepared using the control groups all exhibited a certain degree of secondary emulsification, particularly control groups 8 and 9. Because no siloxane coupling agent was sprayed onto the aggregates during the preparation process, or no early-strength agent was used, the water resistance of the emulsified asphalt mixtures decreased.

[0042] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered exemplary and not restrictive in all respects. Furthermore, it should be understood that although this specification describes embodiments, it does not encompass only one technical solution. This descriptive method is merely for clarity, and those skilled in the art should consider the specification as a whole. The technical solutions in the embodiments can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A water-resistant emulsified asphalt mixture based on epoxy resin, characterized in that: Water-resistant emulsified asphalt mixture based on epoxy resin, the mixture includes the following components by weight: 90-95 parts aggregate, 3-5 parts early strength agent, 1-2 parts water, 2-3 parts mineral powder and 10-15 parts modified emulsified asphalt; The modified emulsified asphalt comprises the following components by weight: 45-55 parts modified asphalt, 3-8 parts emulsifier, 20-25 parts epoxy resin, and 15-22 parts water. The modified asphalt also comprises the following components by weight: 80-100 parts base asphalt, 3-5 parts SBR, 2-5 parts petroleum resin, 1-2 parts toughening agent, and 5-10 parts composite curing agent. The aggregate surface is sprayed with a silane coupling agent, which comprises 20-30% titanate coupling agent and 70-80% isooctyltriethoxysilane. The amount of silane coupling agent used is 0.2-0.3% of the aggregate weight. The composite curing agent comprises the following components by weight fraction: 55-65% polyoxypropylene diamine curing agent and 35-45% phenolic amine curing agent; the emulsifier comprises a cationic emulsifier and a nonionic emulsifier, wherein the mass ratio of the cationic emulsifier to the nonionic emulsifier is 1-3:1; the cationic emulsifier is a quaternary ammonium salt emulsifier, and the nonionic emulsifier is an alkyl glycoside emulsifier; The early strength agent comprises the following components by mass fraction: 50% quick-setting cement, 30% silicate cement, 13% interface agent, 2% expansion agent, 1.5% accelerator, 2% retarder and 1.5% anti-caking agent; The toughening agent is an acrylic polymer, which is a mixture of polybutyl acrylate and epoxy acrylate copolymer.

2. The epoxy resin-based water-resistant emulsified asphalt mixture according to claim 1, characterized in that: The aggregates include coarse aggregates and fine aggregates, with a mass ratio of coarse aggregates to fine aggregates of 1 to 4:

1. The particle size range of the coarse aggregates is 4.75 to 16 mm, and the particle size range of the fine aggregates is ≤4.75 mm.

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