Normal-temperature asphalt, preparation method thereof and application of normal-temperature asphalt in asphalt concrete pavement

Abstract

The invention discloses normal-temperature asphalt, a preparation method thereof and application of the normal-temperature asphalt in an asphalt concrete pavement, and the preparation method of the normal-temperature asphalt comprises the following steps: a) preparing emulsified asphalt; b) preparation of emulsified waste plastics; c) preparing emulsified waste rubber tires; and d) preparing the normal-temperature asphalt: uniformly stirring the emulsified asphalt, the emulsified waste plastics and the emulsified waste rubber tires according to the mass ratio of 1: 0.5: 0.5-1: 1: 1 at room temperature to obtain the normal-temperature asphalt. And uniformly stirring and mixing the normal-temperature asphalt, the stone / steel slag mixture, river sand and filler at room temperature to obtain the normal-temperature asphalt concrete. The normal-temperature asphalt concrete has the properties of rut resistance, water damage resistance, low-temperature crack resistance, environmental protection, long service life and normal-temperature construction, can meet the use requirements of heavy traffic road sections, and can be applied to asphalt concrete pavements as a surface layer material.

Description

Technical Field

[0001] This invention relates to a room-temperature asphalt, its preparation method, and its application in asphalt concrete pavement, belonging to the technical field of asphalt concrete pavement materials. Background Technology

[0002] Currently, asphalt concrete pavement structures typically consist of a subgrade, a base course (composed of a subbase and an upper base course), and a surface course, arranged sequentially from bottom to top. The base course is usually a water-stabilized crushed stone structure, with a thickness generally between 50cm and 70cm. The surface course is typically divided into a base layer, an intermediate layer, and a top layer, with the top layer usually being an asphalt concrete structure. Currently, the asphalt concrete material used for the top layer is usually hot-mix asphalt mixed with heated aggregate mineral fillers at a high temperature of 160℃-180℃. During construction, it needs to be laid and compacted at temperatures exceeding 150℃. This construction method suffers from high energy consumption and significant pollution.

[0003] To address the aforementioned issues, some scholars and institutions are currently researching design and construction methods for warm-mix asphalt pavements, while others are studying design and construction methods for emulsified asphalt pavements. However, both warm-mix and emulsified asphalt exhibit poor resistance to water damage and rutting, resulting in short service lives, which limits their application, particularly the use of room-temperature emulsified asphalt, which is typically only used for pavement maintenance and repair. Carbon emissions from asphalt pavements are a significant component of highway construction. To reduce carbon emissions and achieve the goals of environmentally friendly, efficient, and long-life pavements, it is necessary to develop a room-temperature asphalt with rutting resistance, water damage resistance, low-temperature crack resistance, environmental friendliness, long service life, and the ability to be constructed at room temperatures, along with its preparation method and application in asphalt concrete pavements.

[0004] Waste rubber (usually waste rubber tires) contains both natural and synthetic rubber components, possessing excellent elasticity and aging resistance. Adding it to asphalt can effectively improve the high-temperature stability, low-temperature crack resistance, and fatigue resistance of asphalt mixtures. Waste plastics (e.g., waste PE, PP, PET, PS, EVA, etc.) have good thermoplasticity and weather resistance. Adding them to asphalt can improve the high-temperature stability and low-temperature crack resistance of asphalt mixtures. Therefore, some scholars and institutions are currently adding waste rubber and waste plastics to asphalt, which not only improves the performance of asphalt but also effectively promotes resource recycling and reduces solid waste. This has broad application prospects and significant environmental benefits in promoting green and low-carbon road construction. However, the poor compatibility of waste rubber, waste plastics, and asphalt leads to uneven performance of the modified asphalt. Summary of the Invention

[0005] In view of the above-mentioned problems in the existing technology, the purpose of this invention is to provide room temperature asphalt, its preparation method and its application in asphalt concrete pavement.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a method for preparing room temperature asphalt, comprising the following steps: a) Preparation of emulsified asphalt: Heat the heavy traffic asphalt to 152-158℃ and keep it at that temperature for 25-35 minutes, then set it aside. Heat 20-30 parts by weight of softened water to 63-67℃, then add 1.5-2.5 parts by weight of emulsifier while stirring, and stir until homogeneous. Then add 1-3 parts by weight of stabilizer and stir until homogeneous. Then add 2.5-3.5 parts by weight of waterborne epoxy resin and stir until homogeneous. Then add 1.5-2.5 parts by weight of acrylate emulsion and stir until homogeneous. Then add 2-3 parts by weight of styrene-butadiene latex and stir until homogeneous. Then add 0.8-1.2 parts by weight of interface modifier and stir until homogeneous. Finally, slowly add dilute hydrochloric acid to adjust the pH of the system to 2-3 to obtain the asphalt aqueous phase. Heavy traffic asphalt and asphalt water phase are simultaneously pumped into a colloid mill at a mass ratio of 6:4-9:1 to mix them evenly and obtain emulsified asphalt. b) Preparation of emulsified waste plastics: 40-50 parts by weight of waste plastic granules and 1-3 parts by weight of POE-grafted GMA copolymer are stirred and mixed at 75-85℃ for 25-35 minutes to obtain modified waste plastic granules. Heat 35-45 parts by weight of softened water to 53-57℃, then add 3-5 parts by weight of emulsifier while stirring, and stir until the mixture is uniform. Then add 1.5-2.5 parts by weight of stabilizer and stir until the mixture is uniform. Finally, add sodium hydroxide aqueous solution to adjust the pH of the system to 8-9 to obtain the waste plastic aqueous phase. Modified waste plastic granules and waste plastic aqueous phase are mixed and then subjected to high-speed shear emulsification to obtain emulsified waste plastic; c) Preparation of emulsified waste rubber tires: Mix 1.5-2.5 parts by weight of vegetable oleic acid, 0.8-1.2 parts by weight of sodium bicarbonate, and 1-2 parts by weight of wood vinegar at room temperature until homogeneous to obtain an activator premix. Mix 3-5 parts by weight of softened water and 0.5-1.5 parts by weight of APG emulsifier evenly, then add 6.5-7.5 parts by weight of SBS powder and stir evenly. Then add 1.8-2.2 parts by weight of maleic anhydride, 0.2-0.4 parts by weight of ammonium persulfate and 0.05-0.15 parts by weight of ascorbic acid and stir evenly to obtain SBS grafting premix solution. 35-45 parts by weight of waste rubber tire granules, 2.5-3.5 parts by weight of interface modifier and 3-4 parts by weight of coupling agent are stirred at room temperature for 25-35 minutes. Then, the activator premix is ​​added and stirred at 58-62°C for 20-40 minutes. Then, the SBS grafted premix and 2-4 parts by weight of plasticizer are added and stirred at 58-62°C for 20-40 minutes. Then, the mixture is cooled to below 50°C to obtain a modified rubber mixture. 20-25 parts by weight of softened water, 5-6 parts by weight of emulsifier, and 1-3 parts by weight of stabilizer are stirred and mixed evenly at 45-55℃ to obtain the aqueous phase of waste rubber. Modified rubber mixture and waste rubber aqueous phase are mixed and then subjected to high-speed shear emulsification to obtain emulsified waste rubber tires; d) Preparation of room temperature asphalt: Emulsified asphalt, emulsified waste plastic and emulsified waste rubber tire are mixed evenly at room temperature in a mass ratio of 1:0.5:0.5-1:1:1 to obtain room temperature asphalt.

[0007] In one implementation scheme, in step a), the heavy traffic asphalt is any one of 30#, 50#, 70#, 90#, and 110# heavy traffic asphalt.

[0008] In one embodiment, in step a), the emulsifier is at least one of cationic emulsifier, anionic emulsifier, and nonionic emulsifier; the cationic emulsifier is one or more of octadecyltrimethylammonium chloride, benzalkonium chloride, and octadecylamine hydrochloride; the anionic emulsifier is one or more of sodium dodecyl sulfate, sodium lauryl ether sulfate, sodium dioctyl succinate sulfonate, and fatty alcohol phosphate; and the nonionic emulsifier is one or more of fatty acid polyoxyethylene ether, fatty acid polyoxyethylene ester, and sorbitan laurate. The stabilizer is one or more of the following: clay / cooked clay, kaolin, attapulgite, bentonite, talc, polyacrylamide, polyvinyl alcohol, calcium chloride, and magnesium chloride.

[0009] In one embodiment, in step a), the waterborne epoxy resin is a waterborne epoxy resin with an epoxy equivalent of 450-500 (e.g., any one of Hansen Chemical EPIKOTE™ 6520-WH-53, Guodu Chemical KUKDO YD-011, Shanghai Yuanbang YB-EPW-50, and BASF Baxxodur® Eco 680), the acrylate emulsion is an acrylate emulsion that does not contain APEO substances (e.g., any one of BASF Acronal® 290D, Dow Chemical Primal™ SF-016, Jiangsu Sanmu SM-6188, and Wanhua Chemical Wancryl® 6100), and the styrene-butadiene latex is a formaldehyde-free styrene-butadiene latex (e.g., any one of BASF Styrofan® 250D, Lanxess Chemical Baystal® S 250, and Shandong Qilu SD-628).

[0010] In one embodiment, in steps a) and c), the interface modifier is a sunflower oil-based interface modifier, which is obtained by reacting epoxidized sunflower oil, diethylenetriamine, and ethanolamine in 10-15 parts by weight of deionized water at 60-65°C under the catalysis of a lipase catalyst. Specifically, the preparation of the sunflower oil-based interface modifier includes the following steps: 100 parts by weight of epoxidized sunflower oil, 15-18 parts by weight of diethylenetriamine, 5-8 parts by weight of ethanolamine, 10-15 parts by weight of deionized water, and 0.5-1.0 parts by weight of lipase catalyst were added to a reactor and stirred at 60-65°C for 4-6 hours. After the reaction was completed, the mixture was filtered, washed with water, and dehydrated under vacuum to obtain a sunflower oil-based interface modifier. The lipase catalyst was Novozym 435.

[0011] In one embodiment, in step b), the waste plastic is one or more of polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), and acrylonitrile-butadiene-styrene (ABS); preferably, a mixture of polyethylene (PE) and polypropylene (PP). The POE-grafted GMA copolymer is any one of the following: Shanghai Rizhisheng RSG-101, Guangzhou Jusailong GS-GM01, Nanjing Julong JLR-GM1, Zhejiang Juner JEP-G01, Kingfa Science & Technology, Mitsui Chemicals, Dow Chemical AMPLIFY™ GR216, BASF Ecovio® F Blend C1200, Total Energy LOTRYL® 35BA320, and Shanghai Huayi HY-GM08E.

[0012] In one embodiment, in step b), the emulsifier is one or more of fatty alcohol polyoxyethylene ether, sodium dodecylbenzene sulfonate, and benzyl dimethyl alkyl ammonium chloride; The stabilizer is one or more of montmorillonite, magnesium aluminum hydrotalcite, and polyethylene oxide.

[0013] In one embodiment, in step c), the vegetable oleic acid refers to a mixture of unsaturated fatty acids extracted from vegetable oils (such as soybean oil, rapeseed oil, cottonseed oil, etc.), with the main components being oleic acid (C18:1) and linoleic acid (C18:2), for example, Shandong Bohai BH-FA188, Zhejiang Zancheng ZC-901, etc. The wood vinegar is an acidic liquid produced during the dry distillation of wood. Its main components are acetic acid (5-10%), methanol (2-5%), phenols (1-3%), ketones, etc. For example, Jiangsu Senyou SY-MCL-3, Fujian Luyuan LY-JZ, Zhejiang Zhuhai ZH-100, Shandong Huatai HT-MV, etc.

[0014] In one embodiment, in step c), the APG emulsifier is any one of Guangzhou Tinci TCS-APG0810, Shanghai Fakai APG0814, BASF Plantacare® 810 UP, Corning Chemical Agnique® PG 8105, and China National Light Industry Daily Chemical ZQ-APG0810.

[0015] In one embodiment, in step c), the coupling agent is one or more selected from Si-69, KH-560, isopropoxytris(dioctyl phosphate) titanate, di(dioctyl phosphate) ethylene glycol titanate, and diisopropoxy(ethyl acetoacetate) aluminum. The plasticizer is one or more of the following: paraffin oil, epoxidized soybean oil, epoxidized fatty acid methyl ester, fatty acid ester, triethyl citrate, and phthalates; The emulsifier is one or more of nonylphenol polyoxyethylene ether, ethylene glycol butyl ether, and sorbitan fatty acid esters; The stabilizer is one or more of calcium chloride, sodium carboxymethyl cellulose, fumed silica, and hindered phenolic antioxidants.

[0016] The present invention also provides a room-temperature asphalt prepared by the method.

[0017] The present invention also provides a method for preparing room temperature asphalt concrete, comprising the following operations: mixing 5-10 parts by weight of the room temperature asphalt, 30-65 parts by weight of the aggregate / steel slag mixture, 10-30 parts by weight of the river sand, and 2-8 parts by weight of the filler at room temperature to obtain room temperature asphalt concrete.

[0018] In one embodiment, the aggregate / steel slag mixture is obtained by mixing aggregate and steel slag in a mass ratio of 1:1, wherein the aggregate is at least one of basalt and limestone; and the filler is at least one of lime, gypsum, and cement.

[0019] The present invention also provides a room-temperature asphalt concrete prepared by the method.

[0020] The present invention also provides an application of the aforementioned room-temperature asphalt concrete in concrete pavement, specifically as a surface layer material for asphalt concrete pavement.

[0021] This invention also provides an asphalt concrete pavement, comprising, from bottom to top, a subgrade, a base course, an asphalt sprayed slip layer, a high-ductility high-performance concrete layer, and a room-temperature asphalt concrete surface layer formed by the aforementioned room-temperature asphalt concrete. The base course includes a subbase and an upper base course. The thickness of the asphalt sprayed slip layer is 1-2 mm, and commercially available asphalt can be used, such as Shell Thiopave® series modified asphalt or Shell Cariphalte® DA, Koch PG-grade modified asphalt, Polytec SBS modified asphalt, rubber asphalt, etc.; the thickness of the high-ductility high-performance concrete layer is 80-150 mm, and commercially available high-ductility high-performance concrete can be used, such as Sika® MonoTop® series or Sika® ViscoCrete® series concrete, BASF MasterMatrix® series UHPC, Beijing Huaqian HQ-ECC series engineering cement-based composite materials or HQ-UHPC series ultra-high performance concrete, etc.; the thickness of the room-temperature asphalt concrete surface layer is 20-40 mm.

[0022] Compared with the prior art, the present invention has the following significant advantages: 1. This invention emulsifies and modifies asphalt, waste plastics, and waste rubber tire particles to obtain emulsified asphalt, emulsified waste plastics, and emulsified waste rubber tires, respectively. Then, the emulsified asphalt, emulsified waste plastics, and emulsified waste rubber tires are mixed to obtain room temperature asphalt. The prepared room temperature asphalt is mixed with stone / steel slag mixture, river sand, and filler at room temperature to obtain room temperature asphalt concrete. The prepared room temperature asphalt concrete can be used as a surface material in asphalt concrete pavement. The preparation of room temperature asphalt concrete does not require high-temperature heating, and the production and construction temperature can be controlled at room temperature. Compared with traditional hot-mix asphalt mixture, carbon emissions can be reduced by 75-90 kg per ton, energy consumption can be reduced by more than 80%, and VOCs emission concentration is ≤10mg / m³, which meets the low-carbon road construction standards. 2. In the ambient temperature asphalt concrete provided by this invention, emulsified asphalt, emulsified waste plastic and emulsified waste rubber tire have a synergistic effect. Combined with stone / steel slag mixture, river sand and filler, the ambient temperature asphalt concrete has good resistance to rutting, water damage, low temperature cracking resistance, environmental protection, long service life and can be constructed at ambient temperature, which can meet the requirements of heavy traffic sections. 3. The asphalt concrete pavement provided by the present invention comprises, from bottom to top, a subgrade, a base course, an asphalt spraying slip layer, a high-ductility high-performance concrete layer, and a normal-temperature asphalt concrete surface layer formed by the aforementioned normal-temperature asphalt concrete. The asphalt spraying slip layer, the high-ductility high-performance concrete layer, and the normal-temperature asphalt concrete surface layer together constitute the functional surface layer. The dense skeleton structure of the base course and the high porosity structure of the functional surface layer work together to ensure both load-bearing capacity and drainage performance. The interlayer bond strength is ≥1.0MPa, effectively preventing interlayer slippage. 4. The ambient temperature asphalt concrete provided by this invention makes full use of non-plastic, waste rubber, industrial waste (steel slag) and other waste materials, effectively promotes resource recycling, realizes the reduction of solid waste, and can extend the service life of the road surface to 12-15 years, reduce the maintenance frequency by more than 60%, and significantly reduce the road construction and maintenance costs and carbon emissions throughout the entire life cycle. Detailed Implementation

[0023] The technical solution of the present invention will be further described in detail and completely below with reference to the embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. Experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or as recommended by the manufacturer. Example 1

[0024] I. Preparation of sunflower oil-based interface modifier 100 parts by weight of epoxidized sunflower oil, 16.5 parts by weight of diethylenetriamine, 6.5 parts by weight of ethanolamine, 12.5 parts by weight of deionized water, and 0.8 parts by weight of lipase catalyst Novozym 435 were added to a reactor and stirred at 63°C for 5 hours. After the reaction was completed, the reaction solution was filtered (through a 100-mesh sieve) to remove the solid enzyme catalyst. The resulting crude liquid product was washed twice with warm water at 60°C. The resulting oil phase product was dehydrated under vacuum (-0.09 MPa, 70°C) to obtain a sunflower oil-based interface modifier.

[0025] II. Preparation of Emulsified Asphalt Heat 30# heavy traffic asphalt to 155℃ and keep it at that temperature for 30 minutes; set aside. Heat 25 parts by weight of softened water to 65°C, then add 2 parts by weight of emulsifier (octadecyltrimethylammonium chloride) while stirring, and stir until homogeneous. Then add 2 parts by weight of stabilizer (polyacrylamide) and stir until homogeneous. Then add 3 parts by weight of waterborne epoxy resin (Shanghai Yuanbang YB-EPW-50) and stir until homogeneous. Then add 2 parts by weight of acrylic emulsion (Jiangsu Sanmu SM-6188) and stir until homogeneous. Then add 2.5 parts by weight of styrene-butadiene latex (Shandong Qilu SD-628) and stir until homogeneous. Then add 1 part by weight of sunflower oil-based interface modifier and stir until homogeneous. Then slowly add 10wt% dilute hydrochloric acid to adjust the pH of the system to 2-3 to obtain the asphalt aqueous phase. Heavy traffic asphalt and asphalt water phase are simultaneously pumped into a colloid mill at a mass ratio of 6.5:3.5 to mix them evenly and obtain emulsified asphalt.

[0026] III. Preparation of Emulsified Waste Plastics The mixture of polyethylene (PE) and polypropylene (PP) (mass ratio of 1:1) was crushed to obtain waste plastic granules. 45 parts by mass of waste plastic granules and 2 parts by mass of POE-grafted GMA copolymer (Shanghai Rizhisheng RSG-101) were stirred and mixed at 80°C for 30 minutes to obtain modified waste plastic granules. Heat 40 parts by weight of softened water to 55°C, then add 4 parts by weight of emulsifier (sodium dodecylbenzene sulfonate) while stirring, and stir until the mixture is homogeneous. Then add 2 parts by weight of stabilizer (montmorillonite) and stir until the mixture is homogeneous. Finally, add a 10wt% sodium hydroxide aqueous solution to adjust the pH of the system to 8.5 to obtain the waste plastic aqueous phase. Modified waste plastic granules and aqueous phase of waste plastic were added to a high-speed shear emulsifier for high-speed shear emulsification at a speed of 8000 r / min for 60 minutes to obtain emulsified waste plastic.

[0027] IV. Preparation of Emulsified Waste Rubber Tires Two parts by weight of vegetable oleic acid (Shandong Bohai BH-FA188), one part by weight of sodium bicarbonate, and 1.5 parts by weight of wood vinegar (Jiangsu Senyou SY-MCL-3) were stirred and mixed evenly at room temperature to obtain an activator premix. Mix 4 parts by weight of softened water and 1 part by weight of APG emulsifier (Guangzhou Tianci TCS-APG0810) evenly, then add 7 parts by weight of SBS powder and stir evenly. Then add 2 parts by weight of maleic anhydride, 0.3 parts by weight of ammonium persulfate and 0.1 parts by weight of ascorbic acid and stir evenly to obtain SBS grafting premix. Steel wires and fibers were stripped from waste tires, crushed and sieved to obtain 80-mesh rubber particles. 40 parts by weight of waste rubber tire particles, 3 parts by weight of sunflower oil-based interface modifier and 3.5 parts by weight of coupling agent (KH-560) were stirred at room temperature for 30 minutes. Then the activator premix was added and stirred at 60°C for 30 minutes. Then the SBS grafted premix and 3 parts by weight of plasticizer (paraffin oil) were added and stirred at 60°C for 30 minutes. Then the temperature was lowered to below 50°C to obtain a modified rubber mixture. 23 parts by weight of softened water, 5.5 parts by weight of emulsifier (sorbitan fatty acid ester), and 2 parts by weight of stabilizer (sodium carboxymethyl cellulose) were stirred and mixed evenly at 50°C to obtain the aqueous phase of waste rubber. The modified rubber mixture and the aqueous phase of waste rubber were added to a high-speed shear emulsifier for high-speed shear emulsification at a speed of 6000 r / min for 60 minutes to obtain emulsified waste rubber tires.

[0028] V. Preparation of Asphalt at Room Temperature Emulsified asphalt, emulsified waste plastic, and emulsified waste rubber tires were mixed evenly at room temperature in a mass ratio of 1:0.8:0.5 to obtain room temperature asphalt.

[0029] VI. Preparation of Asphalt Concrete at Normal Temperature Five parts by mass of the ambient temperature asphalt, 60 parts by mass of the aggregate / steel slag mixture (aggregate:steel slag mass ratio of 1:1, aggregate is a mixture of basalt:limestone mass ratio of 1:1), 28 parts by mass of river sand, and 6 parts by mass of filler (plaster:cement mass ratio of 1:1) are mixed evenly at room temperature to obtain ambient temperature asphalt concrete.

[0030] Example 2 I. Preparation of sunflower oil-based interface modifier Same as Example 1.

[0031] II. Preparation of Emulsified Asphalt Heat 50# heavy traffic asphalt to 155℃ and keep it at that temperature for 30 minutes; set aside. Heat 25 parts by weight of softened water to 65°C, then add 2 parts by weight of emulsifier (octadecylamine hydrochloride) while stirring, and stir until homogeneous. Then add 2 parts by weight of stabilizer (polyvinyl alcohol), and stir until homogeneous. Then add 3 parts by weight of waterborne epoxy resin (Shanghai Yuanbang YB-EPW-50), and stir until homogeneous. Then add 2 parts by weight of acrylic emulsion (Jiangsu Sanmu SM-6188), and stir until homogeneous. Then add 2.5 parts by weight of styrene-butadiene latex (Shandong Qilu SD-628), and stir until homogeneous. Then add 1 part by weight of sunflower oil-based interface modifier, and stir until homogeneous. Then slowly add 10wt% dilute hydrochloric acid to adjust the pH of the system to 2-3 to obtain the asphalt aqueous phase. Heavy traffic asphalt and asphalt water phase are simultaneously pumped into a colloid mill at a mass ratio of 6.6:3.4 to mix them evenly and obtain emulsified asphalt.

[0032] III. Preparation of Emulsified Waste Plastics The modified waste plastic granules are the same as in Example 1; 40 parts by weight of softened water were heated to 55°C, and then 4 parts by weight of emulsifier (benzyl dimethyl alkyl ammonium chloride) were added while stirring. The mixture was stirred until homogeneous. Then 2 parts by weight of stabilizer (magnesium aluminum hydrotalcite) were added and stirred until homogeneous. Finally, a 10 wt% sodium hydroxide aqueous solution was added to adjust the pH of the system to 8.5 to obtain the waste plastic aqueous phase. Modified waste plastic granules and aqueous phase of waste plastic were added to a high-speed shear emulsifier for high-speed shear emulsification at a speed of 8000 r / min for 60 minutes to obtain emulsified waste plastic.

[0033] IV. Preparation of Emulsified Waste Rubber Tires Same as Example 1.

[0034] V. Preparation of Asphalt at Room Temperature Emulsified asphalt, emulsified waste plastic, and emulsified waste rubber tires were mixed evenly at room temperature in a mass ratio of 1:0.9:0.5 to obtain room temperature asphalt.

[0035] VI. Preparation of Asphalt Concrete at Normal Temperature 6 parts by mass of the ambient temperature asphalt, 61 parts by mass of the aggregate / steel slag mixture (aggregate:steel slag mass ratio of 1:1, aggregate is a mixture of basalt:limestone mass ratio of 1:1), 27 parts by mass of river sand, and 7 parts by mass of filler (plaster:cement mass ratio of 1:1) are mixed evenly at room temperature to obtain ambient temperature asphalt concrete.

[0036] Example 3 I. Preparation of sunflower oil-based interface modifier Same as Example 1.

[0037] II. Preparation of Emulsified Asphalt Heat 70# heavy traffic asphalt to 155℃ and keep it at that temperature for 30 minutes; set aside. Heat 25 parts by weight of softened water to 65°C, then add 2 parts by weight of emulsifier (sodium dioctyl succinate sulfonate) while stirring, and stir until homogeneous. Then add 2 parts by weight of stabilizer (calcium chloride) and stir until homogeneous. Then add 3 parts by weight of waterborne epoxy resin (Shanghai Yuanbang YB-EPW-50) and stir until homogeneous. Then add 2 parts by weight of acrylic emulsion (Jiangsu Sanmu SM-6188) and stir until homogeneous. Then add 2.5 parts by weight of styrene-butadiene latex (Shandong Qilu SD-628) and stir until homogeneous. Then add 1 part by weight of sunflower oil-based interface modifier and stir until homogeneous. Then slowly add 10 wt% dilute hydrochloric acid to adjust the pH of the system to 2-3 to obtain the asphalt aqueous phase. Heavy traffic asphalt and asphalt water phase are simultaneously pumped into a colloid mill at a mass ratio of 6.7:3.3 to mix them evenly and obtain emulsified asphalt.

[0038] III. Preparation of Emulsified Waste Plastics Same as Example 1.

[0039] IV. Preparation of Emulsified Waste Rubber Tires The modified rubber mixture is the same as in Example 1; 23 parts by weight of softened water, 5.5 parts by weight of emulsifier (nonylphenol polyoxyethylene ether), and 2 parts by weight of stabilizer (sodium carboxymethyl cellulose) were stirred and mixed evenly at 50°C to obtain the aqueous phase of waste rubber. The modified rubber mixture and the aqueous phase of waste rubber were added to a high-speed shear emulsifier for high-speed shear emulsification at a speed of 6000 r / min for 60 minutes to obtain emulsified waste rubber tires.

[0040] V. Preparation of Asphalt at Room Temperature Emulsified asphalt, emulsified waste plastic, and emulsified waste rubber tires were mixed evenly at room temperature in a mass ratio of 1:1:0.5 to obtain room temperature asphalt.

[0041] VI. Preparation of Asphalt Concrete at Normal Temperature 8 parts by mass of the ambient temperature asphalt, 62 parts by mass of the aggregate / steel slag mixture (aggregate:steel slag mass ratio of 1:1, aggregate is a mixture of basalt:limestone mass ratio of 1:1), 26 parts by mass of river sand, and 6 parts by mass of filler (plaster:cement mass ratio of 1:1) are mixed evenly at room temperature to obtain ambient temperature asphalt concrete.

[0042] Example 4 I. Preparation of sunflower oil-based interface modifier Same as Example 1.

[0043] II. Preparation of Emulsified Asphalt Heat 110# heavy traffic asphalt to 155℃ and keep it at that temperature for 30 minutes; set aside. Heat 25 parts by weight of softened water to 65°C, then add 2 parts by weight of emulsifier (sodium lauryl ether sulfate) while stirring, and stir until homogeneous. Then add 2 parts by weight of stabilizer (polyvinyl alcohol), and stir until homogeneous. Then add 3 parts by weight of waterborne epoxy resin (Shanghai Yuanbang YB-EPW-50), and stir until homogeneous. Then add 2 parts by weight of acrylic emulsion (Jiangsu Sanmu SM-6188), and stir until homogeneous. Then add 2.5 parts by weight of styrene-butadiene latex (Shandong Qilu SD-628), and stir until homogeneous. Then add 1 part by weight of sunflower oil-based interface modifier, and stir until homogeneous. Then slowly add 10wt% dilute hydrochloric acid to adjust the pH of the system to 2-3 to obtain the asphalt aqueous phase. Heavy traffic asphalt and asphalt water phase are simultaneously pumped into a colloid mill at a mass ratio of 7:3 to mix evenly and obtain emulsified asphalt.

[0044] III. Preparation of Emulsified Waste Plastics The modified waste plastic granules are the same as in Example 1; Heat 40 parts by weight of softened water to 55°C, then add 4 parts by weight of emulsifier (fatty alcohol polyoxyethylene ether) while stirring, and stir until the mixture is homogeneous. Then add 2 parts by weight of stabilizer (montmorillonite) and stir until the mixture is homogeneous. Finally, add a 10 wt% sodium hydroxide aqueous solution to adjust the pH of the system to 8.5 to obtain the waste plastic aqueous phase. Modified waste plastic granules and aqueous phase of waste plastic were added to a high-speed shear emulsifier for high-speed shear emulsification at a speed of 8000 r / min for 60 minutes to obtain emulsified waste plastic.

[0045] IV. Preparation of Emulsified Waste Rubber Tires The activator premix is ​​the same as in Example 1; The SBS grafted premix solution is the same as in Example 1; The modified rubber mixture is the same as in Example 1; 23 parts by weight of softened water, 5.5 parts by weight of emulsifier (nonylphenol polyoxyethylene ether), and 2 parts by weight of stabilizer (sodium carboxymethyl cellulose) were stirred and mixed evenly at 50°C to obtain the aqueous phase of waste rubber. The modified rubber mixture and the aqueous phase of waste rubber were added to a high-speed shear emulsifier for high-speed shear emulsification at a speed of 6000 r / min for 60 minutes to obtain emulsified waste rubber tires.

[0046] V. Preparation of Asphalt at Room Temperature Emulsified asphalt, emulsified waste plastic, and emulsified waste rubber tires were mixed evenly at room temperature in a mass ratio of 1:1:0.8 to obtain room temperature asphalt.

[0047] VI. Preparation of Asphalt Concrete at Normal Temperature Nine parts by mass of the ambient temperature asphalt, 63 parts by mass of the aggregate / steel slag mixture (aggregate:steel slag mass ratio of 1:1, aggregate is a mixture of basalt:limestone mass ratio of 1:1), 27 parts by mass of river sand, and 6 parts by mass of filler (plaster:cement mass ratio of 1:1) are mixed evenly at room temperature to obtain ambient temperature asphalt concrete.

[0048] Comparative Example 1 I. Preparation of sunflower oil-based interface modifier This step is not required.

[0049] II. Preparation of Emulsified Asphalt Heat 30# heavy traffic asphalt to 155℃ and keep it at that temperature for 30 minutes; set aside. Heat 25 parts by weight of softened water to 65°C, then add 2 parts by weight of emulsifier (octadecyltrimethylammonium chloride) while stirring, and stir until the mixture is homogeneous. Then slowly add 10wt% dilute hydrochloric acid to adjust the pH of the system to 2-3, and then add 2 parts by weight of stabilizer (polyacrylamide), and stir until the mixture is homogeneous to obtain the asphalt aqueous phase. Heavy traffic asphalt and asphalt water phase are simultaneously pumped into a colloid mill at a mass ratio of 6.5:3.5 to mix them evenly and obtain emulsified asphalt.

[0050] III. Preparation of Emulsified Waste Plastics The mixture of polyethylene (PE) and polypropylene (PP) (mass ratio of 1:1) is crushed to obtain waste plastic granules; Heat 40 parts by weight of softened water to 55°C, then add 4 parts by weight of emulsifier (sodium dodecylbenzene sulfonate) while stirring, and stir until the mixture is homogeneous. Then add 2 parts by weight of stabilizer (montmorillonite) and stir until the mixture is homogeneous. Finally, add a 10wt% sodium hydroxide aqueous solution to adjust the pH of the system to 8.5 to obtain the waste plastic aqueous phase. Waste plastic granules and aqueous phase of waste plastic are added to a high-speed shear emulsifier for high-speed shear emulsification at a speed of 8000 r / min for 60 minutes to obtain emulsified waste plastic.

[0051] IV. Preparation of Emulsified Waste Rubber Tires Steel wires and fibers are stripped from waste tires, crushed and screened to obtain 80-mesh rubber granules. 40 parts by weight of waste rubber tire granules and 3.5 parts by weight of coupling agent (KH-560) are stirred at room temperature for 30 minutes, then 3 parts by weight of plasticizer (paraffin oil) are added, and the mixture is stirred at 60°C for 30 minutes. Then the temperature is lowered to below 50°C to obtain a rubber mixture. 23 parts by weight of softened water, 5.5 parts by weight of emulsifier (sorbitan fatty acid ester), and 2 parts by weight of stabilizer (sodium carboxymethyl cellulose) were stirred and mixed evenly at 50°C to obtain the aqueous phase of waste rubber. The rubber mixture and the aqueous phase of waste rubber were added to a high-speed shear emulsifier for high-speed shear emulsification at a speed of 6000 r / min for 60 minutes to obtain emulsified waste rubber tires.

[0052] V. Preparation of Asphalt at Room Temperature Emulsified asphalt, emulsified waste plastic, and emulsified waste rubber tires were mixed evenly at room temperature in a mass ratio of 1:0.8:0.5 to obtain room temperature asphalt.

[0053] VI. Preparation of Asphalt Concrete at Normal Temperature Five parts by mass of the ambient temperature asphalt, 60 parts by mass of the aggregate / steel slag mixture (aggregate:steel slag mass ratio of 1:1, aggregate is a mixture of basalt:limestone mass ratio of 1:1), 28 parts by mass of river sand, and 6 parts by mass of filler (plaster:cement mass ratio of 1:1) are mixed evenly at room temperature to obtain ambient temperature asphalt concrete.

[0054] Comparative Example 2 10 parts by weight of hot-mix asphalt (Xi'an Zhongli Asphalt Co., Ltd., model GAB), 62 parts by weight of aggregate / steel slag mixture (aggregate:steel slag mass ratio of 1:1, aggregate is a mixture of basalt:limestone mass ratio of 1:1), 25 parts by weight of river sand, and 5 parts by weight of filler (plaster:cement mass ratio of 1:1) are added to a mixer and mixed evenly to obtain hot-mix asphalt concrete.

[0055] Comparative Example 3 Eight parts by weight of warm-mix asphalt (China Petroleum & Chemical Corporation, model 70#), 64 parts by weight of aggregate / steel slag mixture (aggregate:steel slag mass ratio of 1:1, aggregate is a mixture of basalt:limestone mass ratio of 1:1), 23 parts by weight of river sand, and 6 parts by weight of filler (plaster:cement mass ratio of 1:1) are added to a mixer and mixed evenly to obtain warm-mix asphalt concrete.

[0056] Performance testing: The performance of the ambient temperature asphalt concrete prepared in Examples 1-4, the ambient temperature asphalt concrete prepared in Comparative Example 1, the hot-mix asphalt concrete prepared in Comparative Example 2, and the warm-mix asphalt concrete prepared in Comparative Example 3 were tested in accordance with the current Technical Specification for Construction of Highway Asphalt Pavement JTG F40-2004. The test results are shown in Table 1.

[0057] Table 1. Test data of asphalt concrete prepared in Examples 1-4 and Comparative Examples 1-3

[0058]

[0059] As shown in Table 1, the ambient temperature asphalt concrete with waste rubber and waste plastic added in Examples 1-4 and Comparative Example 1 has better molding Marshall strength than the hot-mix asphalt concrete in Comparative Example 2 and the warm-mix asphalt concrete in Comparative Example 3, indicating better overall mechanical strength, longer service life and durability. It also has better water immersion Marshall stability and freeze-thaw splitting TSR, indicating better resistance to water damage (water damage). It has better dynamic stability at 60℃, indicating better resistance to rutting. It also has better maximum flexural tensile strain at -10℃, indicating better low-temperature crack resistance. Therefore, the ambient temperature asphalt concrete with waste rubber and waste plastic added has a longer service life, better resistance to water damage, rutting, and low-temperature crack resistance compared to traditional hot-mix asphalt and warm-mix asphalt. In addition, the ambient temperature asphalt concrete can be constructed at room temperature, with lower construction energy consumption and is more environmentally friendly than traditional hot-mix asphalt and warm-mix asphalt. Furthermore, as can be seen from Examples 1-4 and Comparative Example 1, the room-temperature asphalt concrete prepared using the embodiments of the present invention has a longer service life and better resistance to water damage, rutting, and low-temperature cracking compared to the room-temperature asphalt concrete of Comparative Example 1. This is because: Sunflower oil-based interface modifiers were used in the ambient temperature asphalt concrete in Examples 1-4. Sunflower oil-based interface modifiers have an amphiphilic structure, which can significantly enhance the compatibility of hydrophobic materials such as asphalt, plastics, and rubber with water-based systems, thereby effectively improving the Marshall strength, water stability, and low-temperature toughness of asphalt concrete. In Examples 1-4, the emulsified asphalt of the room temperature asphalt concrete uses a variety of high-molecular modifiers such as water-based epoxy resin, acrylic emulsion, and styrene-butadiene latex to form a three-dimensional network structure, which significantly improves the high-temperature stability, adhesion and elastic recovery ability of the asphalt, thereby effectively improving the dynamic stability and flexural strain of the asphalt concrete. In Examples 1-4, the waste plastics and waste rubber in the room temperature asphalt concrete are treated with surface activation, grafting modification and coupling agent to form chemical bonds and physical interweaving with asphalt, which improves the overall strength and flexibility of the material, thereby effectively improving the strength and durability of asphalt concrete. The stabilizers and modifiers (sunflower oil-based interface modifier, waterborne epoxy resin, acrylic emulsion, styrene-butadiene latex, etc.) used in the ambient temperature asphalt concrete in Examples 1-4 work synergistically to enhance the adhesion between asphalt and aggregate, thereby effectively improving the water immersion stability and freeze-thaw splitting strength of asphalt concrete. In Examples 1-4, the POE-grafted GMA copolymer and plasticizer used in the room-temperature asphalt concrete have a synergistic effect, which can effectively improve the low-temperature ductility and crack resistance of asphalt concrete.

[0060] In summary, the room-temperature asphalt concrete provided by this invention exhibits a synergistic effect between emulsified asphalt, emulsified waste plastics, and emulsified waste rubber tires. Combined with aggregate / steel slag mixture, river sand, and fillers, this results in room-temperature asphalt concrete with improved resistance to rutting, water damage, and low-temperature cracking, as well as environmental friendliness, long service life, and the ability to be constructed at room temperature, thus meeting the requirements for use on heavy-duty traffic sections.

[0061] Finally, it should be noted that the above are only some preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A method for preparing room-temperature asphalt, characterized in that, Includes the following steps: a) Preparation of emulsified asphalt: Heat the heavy traffic asphalt to 152-158℃ and keep it at that temperature for 25-35 minutes, then set aside. Heat 20-30 parts by weight of softened water to 63-67℃, then add 1.5-2.5 parts by weight of emulsifier while stirring, and stir until homogeneous. Then add 1-3 parts by weight of stabilizer and stir until homogeneous. Then add 2.5-3.5 parts by weight of waterborne epoxy resin and stir until homogeneous. Then add 1.5-2.5 parts by weight of acrylate emulsion and stir until homogeneous. Then add 2-3 parts by weight of styrene-butadiene latex and stir until homogeneous. Then add 0.8-1.2 parts by weight of interface modifier and stir until homogeneous. Finally, slowly add dilute hydrochloric acid to adjust the pH of the system to 2-3 to obtain the asphalt aqueous phase. Heavy traffic asphalt and asphalt water phase are simultaneously pumped into a colloid mill at a mass ratio of 6:4-9:1 to mix them evenly and obtain emulsified asphalt. b) Preparation of emulsified waste plastics: 40-50 parts by weight of waste plastic granules and 1-3 parts by weight of POE-grafted GMA copolymer are stirred and mixed at 75-85℃ for 25-35 minutes to obtain modified waste plastic granules. Heat 35-45 parts by weight of softened water to 53-57℃, then add 3-5 parts by weight of emulsifier while stirring, and stir until the mixture is uniform. Then add 1.5-2.5 parts by weight of stabilizer and stir until the mixture is uniform. Finally, add sodium hydroxide aqueous solution to adjust the pH of the system to 8-9 to obtain the waste plastic aqueous phase. Modified waste plastic granules and waste plastic aqueous phase are mixed and then subjected to high-speed shear emulsification to obtain emulsified waste plastic; c) Preparation of emulsified waste rubber tires: Mix 1.5-2.5 parts by weight of vegetable oleic acid, 0.8-1.2 parts by weight of sodium bicarbonate, and 1-2 parts by weight of wood vinegar at room temperature until homogeneous to obtain an activator premix. Mix 3-5 parts by weight of softened water and 0.5-1.5 parts by weight of APG emulsifier evenly, then add 6.5-7.5 parts by weight of SBS powder and stir evenly. Then add 1.8-2.2 parts by weight of maleic anhydride, 0.2-0.4 parts by weight of ammonium persulfate and 0.05-0.15 parts by weight of ascorbic acid and stir evenly to obtain SBS grafting premix solution. 35-45 parts by weight of waste rubber tire granules, 2.5-3.5 parts by weight of interface modifier and 3-4 parts by weight of coupling agent are stirred at room temperature for 25-35 minutes. Then, the activator premix is ​​added and stirred at 58-62°C for 20-40 minutes. Then, the SBS grafting premix and 2-4 parts by weight of plasticizer are added and stirred at 58-62°C for 20-40 minutes. Then, the mixture is cooled to below 50°C to obtain a modified rubber mixture. 20-25 parts by weight of softened water, 5-6 parts by weight of emulsifier, and 1-3 parts by weight of stabilizer are stirred and mixed evenly at 45-55℃ to obtain the aqueous phase of waste rubber. Modified rubber mixture and waste rubber aqueous phase are mixed and then subjected to high-speed shear emulsification to obtain emulsified waste rubber tires; d) Preparation of room temperature asphalt: Emulsified asphalt, emulsified waste plastic and emulsified waste rubber tire are mixed evenly at room temperature in a mass ratio of 1:0.5:0.5-1:1:1 to obtain room temperature asphalt.

2. The method for preparing room-temperature asphalt according to claim 1, characterized in that: In step a), the emulsifier is at least one of cationic emulsifier, anionic emulsifier, and nonionic emulsifier. The cationic emulsifier is one or more of octadecyltrimethylammonium chloride, benzalkonium chloride, and octadecylamine hydrochloride. The anionic emulsifier is one or more of sodium dodecyl sulfate, sodium lauryl ether sulfate, sodium dioctyl succinate sulfonate, and fatty alcohol phosphate. The nonionic emulsifier is one or more of fatty acid polyoxyethylene ether, fatty acid polyoxyethylene ester, and sorbitan laurate. The stabilizer is one or more of the following: clay / cooked clay, kaolin, attapulgite, bentonite, talc, polyacrylamide, polyvinyl alcohol, calcium chloride, and magnesium chloride.

3. The method for preparing room-temperature asphalt according to claim 1, characterized in that: In steps a) and c), the interface modifier is a sunflower oil-based interface modifier, which is obtained by reacting epoxidized sunflower oil, diethylenetriamine and ethanolamine in 10-15 parts by mass of deionized water at 60-65°C under the catalysis of lipase catalyst.

4. The method for preparing room-temperature asphalt according to claim 1, characterized in that, In step b), the waste plastic is one or more of polyethylene, polypropylene, polystyrene, polyvinyl chloride, and acrylonitrile-butadiene-styrene.

5. The method for preparing room-temperature asphalt according to claim 1, characterized in that, In step c), the coupling agent is one or more of Si-69, KH-560, isopropoxytris(dioctyl phosphate) titanate, di(dioctyl phosphate) ethylene glycol titanate, and diisopropoxy(ethyl acetoacetate) aluminum; The plasticizer is one or more of the following: paraffin oil, epoxidized soybean oil, epoxidized fatty acid methyl ester, fatty acid ester, triethyl citrate, and phthalates; The emulsifier is one or more of nonylphenol polyoxyethylene ether, ethylene glycol butyl ether, and sorbitan fatty acid esters; The stabilizer is one or more of calcium chloride, sodium carboxymethyl cellulose, fumed silica, and hindered phenolic antioxidants.

6. Room temperature asphalt prepared by the method according to any one of claims 1-5.

7. A method for preparing room-temperature asphalt concrete, characterized in that, The process includes the following steps: mixing 5-10 parts by weight of the ambient temperature asphalt, 30-65 parts by weight of the aggregate / steel slag mixture, 10-30 parts by weight of the river sand, and 2-8 parts by weight of the filler at room temperature until homogeneous, to obtain ambient temperature asphalt concrete.

8. The ambient temperature asphalt concrete prepared by the method of claim 7.

9. The application of the ambient temperature asphalt concrete according to claim 8 in concrete pavement, characterized in that, As a surface layer material for asphalt concrete pavements.

10. An asphalt concrete pavement, characterized in that, From bottom to top, it includes a roadbed, a base course, an asphalt spraying slip layer, a high-ductility high-performance concrete layer, and a normal-temperature asphalt concrete surface layer formed by the normal-temperature asphalt concrete as described in claim 8.

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