Rapid prototyping cold-mixed and cold-laid asphalt thin-layer material and preparation method and application thereof

Abstract

The application discloses a kind of rapid prototyping cold mixing and cold paving asphalt thin layer material and its preparation method and application, it is related to road engineering material technical field, the asphalt thin layer material is composed of the following mass parts materials: aggregate 100 parts, emulsified asphalt 10~12 parts, fiber 0.5~1.5 parts, composite aqueous solution 4~6 parts, cement 1~2 parts, high toughness glue powder 0.6~0.8 parts;Wherein, the emulsified asphalt includes A type emulsified asphalt and B type emulsified asphalt, the raw material of A type emulsified asphalt includes polyurethane;The raw material of B type emulsified asphalt includes polyurethane curing agent.The application realizes the rapid prototyping of asphalt thin layer material after paving by the synergies of A type emulsified asphalt, B type emulsified asphalt;The synergies of waterborne epoxy resin and curing agent in composite aqueous solution, and guarantee that asphalt thin layer material has higher strength, toughness and anti-cracking performance;Prepared asphalt thin layer material can be widely used in road preventive maintenance, repair, improve road performance.

Description

Technical Field

[0001] This invention relates to the field of road engineering materials technology, and in particular to a cold-mixed asphalt thin-layer material suitable for rapid road repair and preventive maintenance, and its preparation method. Background Technology

[0002] Potholes in road surfaces have a significant impact on traffic. The impact loads caused by vehicle bumps and vibrations are extremely harmful, easily affecting driving safety and causing various traffic accidents. Furthermore, rainwater easily seeps into potholes, accelerating the damage to the original road surface, further shortening the road's lifespan, and causing even greater economic losses.

[0003] Asphalt pavement is widely used in road paving projects due to its advantages such as good driving comfort, low noise, and ease of maintenance. However, increased traffic volume, higher vehicle load ratings, higher driving speeds, and overloading have caused serious damage to asphalt pavements. Preventive maintenance techniques are frequently used to improve pavement performance and durability, and ultra-thin wearing courses are one of the key technologies in preventive maintenance.

[0004] Currently, hot-mix asphalt mixtures and cold-mix asphalt mixtures are mainly used for pothole repair and road maintenance. Traditional hot-mix asphalt mixtures suffer from high energy consumption (construction temperature of 160-180℃), significant pollution, and easy segregation during thin-layer construction. Existing cold-mix materials generally suffer from low initial strength (forming strength < 1.5MPa), long open-to-traffic time (> 4 hours), and insufficient interlayer adhesion. Especially in thin-layer (10-20mm) construction scenarios, existing materials struggle to simultaneously meet the technical requirements of rapid curing, skid resistance, wear resistance, and low-temperature construction adaptability. Summary of the Invention

[0005] The purpose of this invention is to provide a rapid-forming cold-mixed and cold-laid asphalt thin-layer material to solve the technical problems existing in the prior art, so that the asphalt thin-layer material can simultaneously meet the requirements of rapid curing, anti-skid and wear-resistant properties, and low-temperature construction.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] This invention provides a rapid-forming cold-mix cold-lay asphalt thin-layer material, the raw materials of which are composed of the following parts by weight: 100 parts aggregate, 10-12 parts emulsified asphalt, 0.5-1.5 parts modified fiber, 4-6 parts composite aqueous solution, 1-2 parts cement, and 0.6-0.8 parts high-toughness rubber powder.

[0008] Preferably, the aggregate comprises 40-50% coarse aggregate with a particle size of 5-10 mm, 10-20% medium aggregate with a particle size of 3-5 mm, and 35-45% fine aggregate with a particle size of 0-3 mm.

[0009] Preferably, the coarse and medium aggregates are made of basalt or diabase, and the fine aggregates are made of limestone.

[0010] Preferably, the aggregate ratio is a discontinuous gradation, with a 2.36mm sieve aperture as the key sieve aperture, and its passing rate is controlled within the range of 28-32%.

[0011] Preferably, the emulsified asphalt is composed of type A emulsified asphalt and type B emulsified asphalt in a mass ratio of 2:1.

[0012] Preferably, the preparation method of the type A emulsified asphalt is as follows: 57-60 parts of base asphalt, 3-5 parts of SBS modifier, 2-3 parts of emulsifier, 2-4 parts of polyurethane, and 0.1-0.3 parts of phosphoric acid are mixed evenly, and water is added to adjust the pH value to 2-2.5.

[0013] Further preferably, the preparation method of the type A emulsified asphalt includes the following steps:

[0014] (1) Mix the base asphalt, SBS modifier and polyurethane evenly to form a mixture;

[0015] (2) Mix the emulsifier and phosphoric acid, add water to adjust the pH, and make soap solution;

[0016] (3) Mix the mixture from step (1) and the soap solution from step (2) to obtain type A emulsified asphalt.

[0017] Preferably, the preparation method of the type B emulsified asphalt is as follows: 57-60 parts of base asphalt, 3-5 parts of SBS modifier, 2-3 parts of emulsifier, 0.5-1 parts of polyurethane curing agent, and 0.1-0.3 parts of phosphoric acid are mixed evenly, and water is added to adjust the pH value to 2-2.5.

[0018] Further preferably, the preparation method of the type B emulsified asphalt includes the following steps:

[0019] (1) Mix the base asphalt, SBS modifier and polyurethane curing agent evenly to form a mixture;

[0020] (2) Mix the emulsifier and phosphoric acid, add water to adjust the pH, and make soap solution;

[0021] (3) Mix the mixture from step (1) and the soap solution from step (2) to obtain type B emulsified asphalt.

[0022] Preferably, the polyurethane curing agent is a modified polyisocyanate compound obtained by hydrophilic modification of polyisocyanate with polyethylene glycol monomethyl ether (MPEG) or polyethylene glycol (PEG).

[0023] Preferably, the SBS modifier is a linear SBS modifier.

[0024] Preferably, the emulsifier is a cationic emulsifier.

[0025] Preferably, the base asphalt is 70# base asphalt.

[0026] Preferably, the modified fiber is a hydrophobic modified fiber, which is obtained by selecting one or more of polyester fiber, basalt fiber or lignin fiber, and drying it after hydrophobic treatment with organosilicon resin solution or polyvinyl alcohol solution. The polyester fiber, basalt fiber or lignin fiber has a length of 3-6 mm and a diameter of 15-25 μm.

[0027] More preferably, the drying conditions are: drying temperature 60°C and drying time 2 hours.

[0028] Preferably, the cement is rapid-hardening sulfoaluminate cement with a specific surface area ≥ 400 m². 2 / kg, initial setting time 15-25min.

[0029] Preferably, the composite aqueous solution is composed of 100 parts water, 0.4 to 0.6 parts waterborne epoxy resin, 0.3 to 0.5 parts surfactant, 0.08 to 0.12 parts curing agent, and 0.4 to 0.6 parts penetration promoter.

[0030] Further preferably, the waterborne epoxy resin is a modified epoxy resin obtained by hydrophilic modification of an organosilicon acrylate hybrid epoxy resin.

[0031] Further preferably, the curing agent is a modified polyamide or modified tertiary amine material obtained by hydrophilic modification of polyamide or modified tertiary amine material.

[0032] Further preferably, the penetration enhancer is a fatty alcohol polyoxyethylene ether.

[0033] More preferably, the surfactant is dodecyl dimethyl benzyl ammonium chloride.

[0034] Preferably, the high-toughness rubber powder is prepared by: taking waste tire rubber powder with a particle size of 0.3-0.6mm, activating it with microwave, adding a tackifier, a toughening agent and a compatibilizer, and then granulating it by high-temperature double-helix extrusion.

[0035] This invention also provides a method for preparing a rapid-forming cold-mix cold-lay asphalt thin-layer material, wherein aggregates and modified fibers are dry-mixed until uniformly dispersed, and composite aqueous solution, type A emulsified asphalt, and type B are added sequentially, and wet-mixed to form a continuous asphalt film. Cement and high-toughness rubber powder are added, and stirring is continued until the material is in a uniform and loose state to obtain the asphalt thin-layer material.

[0036] Preferably, the aggregate is pre-dried at 105°C to a moisture content of <0.5%.

[0037] Preferably, the dry mixing time is 60s, the wet mixing time is 90s, and the stirring time is 45s.

[0038] This invention also provides an application of a rapid-forming cold-mix asphalt thin-layer material in preventive maintenance, repair, and improvement of road performance.

[0039] Preferably, the application method includes the following steps: cleaning the road surface to be repaired to ensure that the surface is clean and free of debris; taking corresponding measures to remove existing markings and signs on the road surface; evenly spreading the rapid-forming cold-mix cold-lay asphalt thin-layer material on the road surface, with the spreading thickness controlled at 1-2 cm; after the emulsified asphalt has initially broken down, compacting it with a road roller to ensure that the material is tightly bonded to the road surface; after compaction, letting it stand for 0.5-1 hour until the material has solidified, at which point traffic can be opened.

[0040] The present invention discloses the following technical effects:

[0041] A two-component emulsified asphalt system is combined with a composite aqueous solution. The polyurethane in type A emulsified asphalt and the polyurethane curing agent in type B emulsified asphalt undergo a curing reaction after demulsification, rapidly solidifying the thin asphalt layer. By adjusting the ratio of the two emulsified asphalts, the demulsification rate can be precisely controlled. Furthermore, cement hydration consumes water in the mixture, increasing the concentration of water-based epoxy resin and curing agent in the composite aqueous solution, leading to rapid curing and further accelerating the asphalt material's solidification rate. This allows for rapid shaping of the cold-mixed asphalt mixture after paving, reducing the time required for road opening after maintenance. High-toughness rubber powder further enhances the mixture's toughness and reduces traffic noise after the thin overlay is opened to traffic. A penetration accelerator improves interlayer bond strength, overcoming the weak interlayer interface problem of traditional cold-mixed materials. Detailed Implementation

[0042] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0043] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0044] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0045] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0046] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0047] This invention provides a rapid-forming cold-mix cold-lay asphalt thin-layer material, characterized in that the raw materials consist of the following parts by weight: 100 parts aggregate, 10-12 parts emulsified asphalt, 0.5-1.5 parts modified fiber, 4-6 parts composite aqueous solution, 1-2 parts cement, and 0.6-0.8 parts high-toughness rubber powder. The emulsified asphalt includes type A emulsified asphalt and type B emulsified asphalt. The type A emulsified asphalt raw material includes polyurethane; the type B emulsified asphalt raw material includes a polyurethane curing agent.

[0048] In some embodiments of the present invention, the aggregate comprises 40-50% coarse aggregate with a particle size of 5-10 mm, 10-20% medium aggregate with a particle size of 3-5 mm, and 35-45% fine aggregate with a particle size of 0-3 mm.

[0049] In some embodiments of the present invention, the coarse and medium aggregates are made of basalt or diabase, and the fine aggregates are made of limestone.

[0050] In some embodiments of the present invention, the aggregate ratio is a discontinuous gradation, with a 2.36mm sieve aperture as the key sieve aperture, and its passing rate is controlled within the range of 28-32%.

[0051] In some embodiments of the present invention, the emulsified asphalt is composed of type A emulsified asphalt and type B emulsified asphalt in a mass ratio of 2:1.

[0052] In some embodiments of the present invention, the preparation method of the type A emulsified asphalt is as follows: 57-60 parts of base asphalt, 3-5 parts of SBS modifier, 2-3 parts of emulsifier, 2-4 parts of polyurethane, and 0.1-0.3 parts of phosphoric acid are mixed evenly, and water is added to adjust the pH value to 2-2.5.

[0053] As a typical but not limiting example, the method for preparing type A emulsified asphalt includes the following steps:

[0054] The base asphalt, SBS modifier, and polyurethane are mixed evenly to form a mixture;

[0055] Mix emulsifier and phosphoric acid, add water to adjust the pH, and make soap solution;

[0056] The above mixture and the soap solution are mixed to obtain type A emulsified asphalt.

[0057] In some embodiments of the present invention, the preparation method of the type B emulsified asphalt is as follows: 57-60 parts of base asphalt, 3-5 parts of SBS modifier, 2-3 parts of emulsifier, 0.5-1 parts of polyurethane curing agent, and 0.1-0.3 parts of phosphoric acid are mixed evenly, and water is added to adjust the pH value to 2-2.5.

[0058] As a typical but not limiting example, the method for preparing type B emulsified asphalt includes the following steps:

[0059] (1) Mix the base asphalt, SBS modifier and polyurethane curing agent evenly to form a mixture;

[0060] (2) Mix the emulsifier and phosphoric acid, add water to adjust the pH, and make soap solution;

[0061] (3) Mix the mixture from step (1) and the soap solution from step (2) to obtain type B emulsified asphalt.

[0062] In some embodiments of the present invention, the polyurethane curing agent is a modified polyisocyanate compound obtained by hydrophilic modification of polyisocyanate with polyethylene glycol monomethyl ether (MPEG) and polyethylene glycol (PEG). This polyurethane curing agent not only possesses a certain degree of hydrophilicity, but its -NCO groups are also encapsulated, allowing it to remain stably in water for a period of time, which is beneficial for the workability and application of the mixture. Compared to single-component polyurethane materials, the introduction of the polyurethane curing agent can not only improve the crosslinking degree and cohesive energy of the cured material, but also enhance the strength and weather resistance of the mixture.

[0063] In some embodiments of the present invention, the modified fiber is a hydrophobic modified fiber, obtained by selecting one or more of polyester fiber, basalt fiber, or lignin fiber, and drying it after hydrophobic treatment with organosilicon resin solution or polyvinyl alcohol solution. The polyester fiber, basalt fiber, or lignin fiber has a length of 3-6 mm and a diameter of 15-25 μm. After hydrophobic modification, the fibers are prevented from clumping due to electrostatic water absorption, improving the dispersion uniformity of the modified fibers in the cold-mixed and cold-laid mixture, forming a three-dimensional network structure reinforcement mechanism, and significantly improving the crack resistance of the thin-layer material.

[0064] In some embodiments of the present invention, the cement is rapid-hardening sulfoaluminate cement with a specific surface area ≥ 400 m². 2 / kg, initial setting time 15-25min.

[0065] In some embodiments of the present invention, the composite aqueous solution is composed of 100 parts water, 0.4 to 0.6 parts waterborne epoxy resin, 0.3 to 0.5 parts surfactant, 0.08 to 0.12 parts curing agent, and 0.4 to 0.6 parts penetration promoter.

[0066] This invention also provides a method for preparing a rapid-forming cold-mix cold-lay asphalt thin-layer material, characterized in that aggregates and modified fibers are dry-mixed until uniformly dispersed, and then composite aqueous solution, type A emulsified asphalt, and type B are added sequentially, followed by wet mixing to form a continuous asphalt film. Cement and high-toughness rubber powder are added, and the mixture is stirred until the material is in a uniform and loose state to obtain the asphalt thin-layer material.

[0067] In some embodiments of the present invention, the aggregate is pre-dried at 105°C to a moisture content of <0.5%.

[0068] In some embodiments of the present invention, the dry mixing time is 60s, the wet mixing time is 90s, and the stirring time is 45s.

[0069] In the following embodiments and comparative examples of the present invention, the waterborne epoxy resin is a modified epoxy resin obtained by hydrophilic modification of organosilicon acrylate hybrid epoxy resin; the curing agent is a modified polyamide or modified tertiary amine material obtained by hydrophilic modification of polyamide or tertiary amine material; the penetration promoter is fatty alcohol polyoxyethylene ether; the surfactant is dodecyl dimethyl benzyl ammonium chloride; the preparation method of the high-toughness rubber powder is as follows: waste tire rubber powder with a particle size of 0.3-0.6 mm is subjected to microwave activation treatment, and tackifier, toughening agent and compatibilizer are added, followed by high-temperature twin-screw extrusion granulation.

[0070] Example 1

[0071] A rapid-forming cold-mix asphalt thin-layer material, composed of the following raw materials in parts by weight:

[0072] 100 parts aggregate, 12 parts emulsified asphalt, 1.5 parts modified basalt fiber, 4 parts composite aqueous solution, 2 parts cement, and 0.8 parts high-toughness rubber powder.

[0073] The aggregates consist of 45 parts of fine limestone crushed stone with a particle size of 0-3mm, 15 parts of medium basalt crushed stone with a particle size of 3-5mm, and 40 parts of coarse basalt crushed stone with a particle size of 5-10mm; the passing rate through a 2.36mm sieve is 31.4%.

[0074] Emulsified asphalt includes type A emulsified asphalt and type B emulsified asphalt, with 8 parts of type A emulsified asphalt and 4 parts of type B emulsified asphalt.

[0075] The preparation method of type A emulsified asphalt is as follows: 57 parts of base asphalt, 3 parts of SBS modifier, and 2 parts of polyurethane are mixed to form a mixture; 2 parts of emulsifier and 0.1 parts of phosphoric acid are added with water to adjust the pH value to 2.5 to form a soap solution; the soap solution is added to the mixture to obtain type A emulsified asphalt.

[0076] The preparation method of type B emulsified asphalt is as follows: 57 parts of base asphalt, 3 parts of SBS modifier, and 0.5 parts of polyurethane curing agent are mixed to form a mixture; 2 parts of emulsifier and 0.1 parts of phosphoric acid are added with water to adjust the pH value to 2.5 to form a soap solution; the soap solution is added to the mixture to obtain type B emulsified asphalt.

[0077] The modified basalt fiber has a length of 6 mm. The modification method is as follows: first, the basalt fiber is initially dispersed, then it is soaked in an organosilicon resin solution for 2 hours and then dried (60℃, 2 hours) to constant weight.

[0078] The composite aqueous solution contains 100 parts water, 0.5 parts surfactant, 0.6 parts waterborne epoxy resin, 0.12 parts curing agent, and 0.6 parts penetration promoter.

[0079] A method for preparing a rapid-form cold-mix asphalt thin-layer material, the specific steps of which are as follows:

[0080] (1) The aggregates were dried at 105℃ until the moisture content was <0.5%;

[0081] (2) Dry mix the aggregate and modified fiber at 10-15℃ for 60s until they are evenly dispersed;

[0082] (3) Add the composite aqueous solution, type A emulsified asphalt, and type B emulsified asphalt in sequence, and mix wet for 90 seconds to form a continuous asphalt film;

[0083] (4) Add cement and high-toughness adhesive powder, and continue stirring for 45 seconds until the material is in a uniform and loose state to obtain a rapid-forming cold-mixed cold-laying asphalt thin-layer material.

[0084] Example 2:

[0085] A rapid-forming cold-mix asphalt thin-layer material, composed of the following raw materials in parts by weight:

[0086] 100 parts aggregate, 11 parts emulsified asphalt, 1.0 part modified basalt fiber, 5 parts composite aqueous solution, 1.5 parts cement, and 0.7 parts high-toughness rubber powder.

[0087] The aggregates consist of 40 parts of 0-3mm limestone crushed stone fine aggregate, 10 parts of 3-5mm basalt crushed stone medium aggregate, and 50 parts of 5-10mm basalt crushed stone coarse aggregate; the 2.36mm sieve passing rate is 29.3%.

[0088] Emulsified asphalt includes type A emulsified asphalt and type B emulsified asphalt, with 8 parts of type A emulsified asphalt and 4 parts of type B emulsified asphalt.

[0089] The preparation method of type A emulsified asphalt is as follows: 58 parts of base asphalt, 4 parts of SBS modifier, and 3 parts of polyurethane are mixed evenly to form a mixture; 2.5 parts of emulsifier and 0.2 parts of phosphoric acid are added with water to adjust the pH value to 2.2 to form a soap solution; the soap solution is added to the mixture to make type A emulsified asphalt.

[0090] The preparation method of type B emulsified asphalt is as follows: 58 parts of base asphalt, 4 parts of SBS modifier, and 0.75 parts of polyurethane curing agent are mixed evenly to form a mixture; 2.5 parts of emulsifier and 0.2 parts of phosphoric acid are added with water to adjust the pH value to 2.2 to form a soap solution, and the soap solution is added to the mixture to form type B emulsified asphalt.

[0091] The modified basalt fiber has a length of 6 mm. The modification method is as follows: first, the basalt fiber is initially dispersed, then it is soaked in an organosilicon resin solution for 2 hours and dried at 60°C for 2 hours until constant weight.

[0092] The composite aqueous solution contains 100 parts water, 0.4 parts surfactant, 0.5 parts waterborne epoxy resin, 0.1 parts curing agent, and 0.5 parts penetration promoter.

[0093] A rapid prototyping method for preparing cold-mixed and cold-laid asphalt thin-layer materials is as follows:

[0094] (1) The aggregates were dried at 105℃ until the moisture content was <0.5%;

[0095] (2) Dry mix the aggregate and modified fiber at 10-15℃ for 60s until they are evenly dispersed;

[0096] (3) Add the composite aqueous solution, type A emulsified asphalt, and type B emulsified asphalt in sequence, and mix wet for 90 seconds to form a continuous asphalt film;

[0097] (4) Add cement and high-toughness adhesive powder, and continue stirring for 45 seconds until the material is in a uniform and loose state to obtain a rapid-forming cold-mixed cold-laying asphalt thin-layer material.

[0098] Example 3:

[0099] A rapid-forming cold-mix asphalt thin-layer material, composed of the following raw materials in parts by weight:

[0100] 100 parts aggregate, 10 parts emulsified asphalt, 0.5 parts modified polyester fiber, 6 parts composite aqueous solution, 1 part cement, and 0.6 parts high-toughness rubber powder.

[0101] The aggregates consist of 35 parts of 0-3mm limestone crushed stone fine aggregate, 20 parts of 3-5mm basalt crushed stone medium aggregate, and 45 parts of 5-10mm basalt crushed stone coarse aggregate; the 2.36mm sieve passing rate is 28.3%.

[0102] Emulsified asphalt includes type A emulsified asphalt and type B emulsified asphalt, with 8 parts of type A emulsified asphalt and 4 parts of type B emulsified asphalt.

[0103] The preparation method of type A emulsified asphalt is as follows: 60 parts of base asphalt, 5 parts of SBS modifier, and 4 parts of polyurethane are mixed evenly to form a mixture; 3 parts of emulsifier and 0.3 parts of phosphoric acid are added with water to adjust the pH value to 2.0 to form a soap solution, and the soap solution is added to the mixture to make type A emulsified asphalt.

[0104] The preparation method of type B emulsified asphalt is as follows: 60 parts of base asphalt, 5 parts of SBS modifier, and 1 part of polyurethane curing agent are mixed evenly to form a mixture; 3 parts of emulsifier and 0.3 parts of phosphoric acid are added with water to adjust the pH value to 2.0 to form a soap solution; the soap solution is added to the mixture to make type B emulsified asphalt (60℃, 2h).

[0105] The modified polyester fiber has a length of 6 mm. The modification method is as follows: first, the fiber is initially dispersed, then it is soaked in a polyvinyl alcohol solution for 2 hours and then dried to constant weight.

[0106] The composite aqueous solution contains 100 parts water, 0.4 parts surfactant, 0.4 parts waterborne epoxy resin, 0.08 parts curing agent, and 0.4 parts penetration promoter.

[0107] A method for preparing a rapid-form cold-mix asphalt thin-layer material, the specific steps of which are as follows:

[0108] (1) The aggregates were dried at 105℃ until the moisture content was <0.5%;

[0109] (2) Dry mix the aggregate and modified fiber at 10-15℃ for 60s until they are evenly dispersed;

[0110] (3) Add the composite aqueous solution, type A emulsified asphalt, and type B in sequence, and mix wet for 90 seconds to form a continuous asphalt film.

[0111] (4) Add cement and high-toughness adhesive powder, and continue stirring for 45 seconds until the material is in a uniform and loose state to obtain a rapid-forming cold-mixed cold-laying asphalt thin-layer material.

[0112] Comparative Example 1:

[0113] A cold-mixed asphalt mixture I;

[0114] The raw material components of cold-mixed asphalt mixture I, according to parts by weight, are as follows:

[0115] The mixture consists of 45 parts of 5-10mm basalt crushed stone, 20 parts of 3-5mm basalt crushed stone, 35 parts of 0-3mm limestone manufactured sand, 5 parts of water, 2 parts of ordinary road silicate cement, and 10 parts of SBS modified emulsified asphalt; the modified emulsified asphalt has a solid content of 61% and a softening point of 76℃.

[0116] A method for preparing cold-mixed cold-laid asphalt mixture I involves mixing 5-10mm basalt crushed stone, 3-5mm basalt crushed stone, and 0-3mm limestone manufactured sand evenly, adding water and stirring for 60 seconds; then adding emulsified asphalt and stirring for 45 seconds to form cold-mixed cold-laid asphalt mixture I, and curing it at 60℃ for 12 hours.

[0117] Comparative Example 2

[0118] A cold-mix cold-lay asphalt mixture II, wherein, by mass parts, the raw material components of the cold-mix cold-lay asphalt mixture II are:

[0119] The mixture consists of 45 parts of 5-10mm basalt crushed stone, 15 parts of 3-5mm basalt crushed stone, 40 parts of 0-3mm limestone manufactured sand, 6 parts of water, 1.5 parts of ordinary road silicate cement, 0.5 parts of basalt fiber, and 11 parts of SBS modified emulsified asphalt; the modified emulsified asphalt has a solid content of 61% and a softening point of 76℃.

[0120] A method for preparing a cold-mixed asphalt mixture II involves mixing fiber, 5-10mm basalt crushed stone, 3-5mm basalt crushed stone, and 0-3mm limestone manufactured sand evenly, adding water and stirring for 60 seconds; then adding emulsified asphalt and stirring for 45 seconds to form a cold-mixed asphalt mixture, which is then cured at 60℃ for 12 hours.

[0121] Comparative Example 3

[0122] A cold-mixed asphalt mixture III is disclosed, wherein the difference between cold-mixed asphalt mixture III and Example 1 is that, in cold-mixed asphalt mixture III, drinking water of the same mass fraction is used to replace the composite aqueous solution in Example 1, while the other materials and their mass fractions are the same as in Example 1.

[0123] The preparation method of cold-mixed and cold-laid mixture III is the same as that in Example 1.

[0124] Comparative Example 4

[0125] A cold-mixed cold-laid asphalt mixture IV, wherein the difference between cold-mixed cold-laid asphalt mixture IV and Example 1 is that 12 parts of emulsified asphalt in cold-mixed cold-laid asphalt mixture IV are type A emulsified asphalt; wherein the composition of each material of type A emulsified asphalt is the same as that in Example 1, and the remaining materials and mass fractions are the same as those in Example 1.

[0126] The preparation method of cold-mixed asphalt mixture IV is the same as that in Example 1.

[0127] Comparative Example 5

[0128] A cold-mixed cold-laid asphalt mixture V, wherein the difference between cold-mixed cold-laid asphalt mixture V and Example 1 is that the 12 parts of emulsified asphalt used in cold-mixed cold-laid asphalt mixture V are all type B emulsified asphalt; wherein the composition of each material of type B emulsified asphalt is the same as that of Example 1, and the remaining materials and mass fractions are the same as those of Example 1.

[0129] The preparation method of cold-mixed asphalt mixture V is the same as that in Example 1.

[0130] Comparative Example 6

[0131] A cold-mixed cold-laid asphalt mixture VI, wherein the difference between cold-mixed cold-laid asphalt mixture VI and Example 1 is that the 1.5 parts of basalt fiber used in cold-mixed cold-laid asphalt mixture VI are pre-dispersed, dried and directly added to the mixture without hydrophobic treatment, and the remaining materials and mass fractions are the same as in Example 1.

[0132] The preparation method of cold-mixed asphalt mixture VI is the same as that in Example 1.

[0133] The cold-mixed asphalt mixtures of Examples 1-3 and Comparative Examples 1-6 were tested for relevant properties in accordance with the slurry mixture standard specified in the "Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011). The results are shown in Table 1 below.

[0134] Marshall specimens were prepared from the cold-mixed asphalt mixtures of Examples 1-3 and Comparative Examples 1-6. A certain mass of the mixture was placed into a Marshall mold, compacted 50 times on both sides at room temperature, and then cured in an oven at 110℃ for 24 hours. After cooling to room temperature, it was compacted 25 times on both sides and demolded to form a Marshall specimen. Similarly, a certain mass of the mixture was placed into a rutting mold, compacted 10 times (20 times) at room temperature, and then cured in an oven at 110℃ for 24 hours. After cooling to room temperature, it was compacted 2 times (4 times) to form a rutting specimen. The relevant properties were tested according to the standards specified in the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTG E20-2011), and the results are shown in Table 2.

[0135] Table 1. Performance Test Results of Cold-Mixed and Cold-Laminated Slurry Mixture

[0136]

[0137] Table 2 Performance Test Results of Cold-Mixed Asphalt Mixtures

[0138]

[0139] As can be seen from the performance test results of Examples 1-3 and Comparative Examples 1-2 in Table 1, the rapid-forming cold-mix cold-lay asphalt thin-layer material formed by this technical solution has a faster forming speed than ordinary emulsified asphalt mixture. It can achieve moderate forming in 30 minutes and complete forming in 60 minutes. Traditional emulsified asphalt slurry mixture can only achieve preliminary forming or even no forming in 30 minutes. In comparison, the cold-mix cold-lay asphalt thin-layer material obtained by this technology can realize rapid opening of traffic and reduce the impact of preventive maintenance on road traffic. Meanwhile, comparing Example 1 and Comparative Example 3, without the addition of the composite aqueous solution, the strength formation was slower, and the later abrasion value also increased, indicating that the composite aqueous solution helps the cold-mixed cold-laid asphalt mixture to form strength and improves the durability of the mixture after molding. Comparing Example 1 and Comparative Examples 4-5, using only Type A emulsified asphalt or Type B emulsified asphalt cannot achieve the purpose of rapid molding of cold-mixed cold-laid asphalt mixture, indicating that when Type A emulsified asphalt and Type B emulsified asphalt are used together, a cross-linking reaction will occur, rapidly forming strength and further improving durability. Comparing Example 1 and Comparative Example 6, without hydrophobic treatment of the fibers, the mixing time is short, which will cause the fibers to clump in the mixture and be difficult to disperse, resulting in poor workability of the mixture.

[0140] As can be seen from the performance test results of the mixtures in Examples 1-3 and Comparative Examples 1-2 in Table 2, the cold-mixed cold-laid thin-layer material formed by this technical solution has better strength, water stability, and high-temperature rutting resistance after molding than ordinary cold-mixed cold-laid thin-layer material. This indicates that the cold-mixed cold-laid thin layer formed by this technology has better service capability and a longer service life in harsh environments. Meanwhile, comparing Example 1 and Comparative Example 3, without the addition of the composite aqueous solution, its strength, water stability, and high-temperature rutting resistance all decreased, and its resistance to loosening under harsh environments was also worse than that of the mixture in Example 1. This indicates that the addition of the composite aqueous solution further induces a chemical reaction, which helps to improve the performance of the mixture and enhances its service capability in harsh environments. Comparing Example 1 and Comparative Examples 4-5, the performance of using type A emulsified asphalt or type B emulsified asphalt alone is worse than that of using both in combination. Comparing Example 1 and Comparative Example 6, without hydrophobic treatment of the fibers, the performance of the mixture will drop sharply, and its water stability and resistance to loosening are poor, making it difficult to meet the service environment of high temperature and high humidity in the south.

[0141] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A rapid-forming cold-mix asphalt thin-layer material, characterized in that, The raw materials consist of the following parts by weight: 100 parts aggregate, 10-12 parts emulsified asphalt, 0.5-1.5 parts modified fiber, 4-6 parts composite aqueous solution, 1-2 parts cement, and 0.6-0.8 parts high-toughness rubber powder. The emulsified asphalt includes type A emulsified asphalt and type B emulsified asphalt. The raw material of type A emulsified asphalt includes polyurethane, and the raw material of type B emulsified asphalt includes polyurethane curing agent. The emulsified asphalt is composed of type A emulsified asphalt and type B emulsified asphalt in a mass ratio of 2:1; The preparation method of the type A emulsified asphalt is as follows: 57-60 parts by weight of base asphalt, 3-5 parts by weight of SBS modifier, 2-3 parts by weight of emulsifier, 2-4 parts by weight of polyurethane, and 0.1-0.3 parts by weight of phosphoric acid are mixed evenly, and water is added to adjust the pH value to 2-2.

5. The preparation method of the type B emulsified asphalt is as follows: 57-60 parts by weight of base asphalt, 3-5 parts by weight of SBS modifier, 2-3 parts by weight of emulsifier, 0.5-1 parts by weight of polyurethane curing agent, and 0.1-0.3 parts by weight of phosphoric acid are mixed evenly, and water is added to adjust the pH value to 2-2.

5. The polyurethane curing agent is polyethylene glycol monomethyl ether or a modified polyisocyanate compound obtained by hydrophilic modification of polyisocyanate with polyethylene glycol. The modified fiber is a hydrophobic modified fiber; the preparation steps of the hydrophobic modified fiber are as follows: select one or more of polyester fiber, basalt fiber or lignin fiber, and obtain it by hydrophobic treatment with organosilicon resin solution or polyvinyl alcohol solution and then drying. The polyester fiber, basalt fiber, or lignin fiber has a length of 3–6 mm and a diameter of 15–25 μm; the cement is rapid-hardening sulfoaluminate cement with a specific surface area ≥400 m². 2 / kg, initial setting time 15-25min; By weight, the composite aqueous solution comprises 100 parts water, 0.4-0.6 parts waterborne epoxy resin, 0.3-0.5 parts surfactant, 0.08-0.12 parts curing agent, and 0.4-0.6 parts penetration promoter; The waterborne epoxy resin is a modified epoxy resin obtained by hydrophilic modification of an organosilicon acrylate hybrid epoxy resin; the curing agent is a modified polyamide or modified tertiary amine material obtained by hydrophilic modification of a polyamide or tertiary amine material; the penetration promoter is a fatty alcohol polyoxyethylene ether; and the surfactant is dodecyl dimethyl benzyl ammonium chloride. The high-toughness rubber powder is prepared by: taking waste tire rubber powder with a particle size of 0.3-0.6 mm, activating it with microwave, adding tackifier, toughening agent and compatibilizer, and then granulating it by high-temperature double spiral extrusion.

2. The rapid prototyping cold-mix cold-lay asphalt thin-layer material according to claim 1, characterized in that, The aggregate comprises 40-50% coarse aggregate with a particle size of 5-10 mm, 10-20% medium aggregate with a particle size of 3-5 mm, and 35-45% fine aggregate with a particle size of 0-3 mm. The coarse and medium aggregates are selected from basalt or diabase, and the fine aggregates are selected from limestone. The aggregate mix is ​​a discontinuous gradation, with a 2.36 mm sieve as the key sieve size, and the passing rate is controlled within the range of 28-32%.

3. A method for preparing a rapid-forming cold-mix asphalt thin-layer material as described in claim 1, characterized in that, The aggregate and the modified fiber are dry-mixed until uniformly dispersed. Then, a composite aqueous solution and emulsified asphalt are added sequentially, and wet-mixed to form a continuous asphalt film. Cement and high-toughness rubber powder are added, and the mixture is stirred until the material is in a uniform and loose state to obtain a thin asphalt layer material.

4. The method for preparing rapid-form cold-mix cold-lay asphalt thin-layer material according to claim 3, characterized in that, The aggregate is further dried to a moisture content of <0.5% at 105°C before use; the dry mixing time is 60s, the wet mixing time is 90s, and the stirring time is 45s.

5. The application of the rapid-forming cold-mix cold-lay asphalt thin-layer material according to claim 1 or the preparation method of the rapid-forming cold-mix cold-lay asphalt thin-layer material according to claim 3 in road preventive maintenance, repair, and improvement of road performance.

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