A kind of factory-mixed hot recycled asphalt mixture and preparation method thereof

Abstract

The invention discloses a factory-mixed hot-regenerated asphalt mixture. The raw materials of the mixture include the following components in parts by weight: 80-90 parts of old SBS asphalt mixture, 4-8 parts of asphalt, 10-20 parts of aggregate, 2-6 parts of mineral powder, 1-3 parts of polyvinyl chloride powder, 1-3 parts of warm mix agent, and 1-3 parts of composite regeneration agent; the raw materials of the composite regeneration agent include in parts by weight 90-110 parts of furfural extracted oil, 5-10 parts of triallyl isocyanurate, 2-6 parts of triethoxysilane, 4-10 parts of three-dimensional porous material, 3-8 parts of penetrant, 20-30 parts of toluene-2,4-diisocyanate, 10-20 parts of terminal hydroxyl polybutadiene, 5-12 parts of plasticizer, and 5-10 parts of tackifier; the hot-regenerated asphalt mixture has enhanced high-temperature stability, low-temperature stability and water stability, and has good anti-skid performance and sound absorption performance. In the application of the factory-mixed hot-regenerated asphalt mixture engineering, the mixing amount of milling material can reach more than 85%, thereby saving economic cost.

Description

Technical Field

[0001] The invention relates to a regenerated asphalt mixture, and in particular to a factory-mixed hot regenerated asphalt mixture and a preparation method thereof. Background Art

[0002] Asphalt pavement recycling is a process of excavating, recycling, crushing, screening, adding appropriate amounts of new aggregates and new asphalt, remixing, and forming a recycled asphalt mixture that meets the road performance requirements, and then using it to pave the road or base. According to the construction temperature, asphalt pavement recycling technology can be divided into hot recycling and cold recycling; according to the different waste material mixing sites, it can be divided into on-site recycling and factory-mixed recycling. Therefore, asphalt pavement recycling technology includes: factory-mixed hot recycling, on-site hot recycling, factory-mixed cold recycling, on-site cold recycling and other construction methods. Factory-mixed hot recycling: It is to recycle the old asphalt mixture and concentrate it in the recycling mixing plant. Through crushing and screening, and according to the asphalt content, asphalt aging degree, crushed stone grading and other indicators in the recycled material, a certain amount of new aggregates, asphalt and regeneration agent (if necessary) and other materials are added, and then heated and mixed into a recycled mixture that meets the technical performance requirements of the road. Factory-mixed hot recycled asphalt mixture can be used for all pavement surface layers. The pavement paved with it and the pavement paved with a mixture made entirely of new materials almost meet the same performance requirements. For waste asphalt mixtures, hot recycling is an ideal recycling method that can maximize the role of asphalt pavement waste. The component blending theory is generally used in the design of the hot recycled mixture ratio. The performance of aged asphalt in RAP is restored by adding a higher grade asphalt or adding a regeneration agent. This not only increases the production cost of hot recycled asphalt mixtures, but also reduces the high temperature stability of hot recycled asphalt mixtures. Traditional hot recycled asphalt mixtures also have the problem of poor low temperature performance and fatigue resistance, which to a certain extent limits the promotion and application of hot recycled asphalt mixtures with high RAP content. In addition, the stability and skid resistance of hot recycled asphalt mixtures need to be further improved, and the sound absorption needs to be further strengthened.

[0003] Therefore, it is necessary to solve the problems of stability, fatigue resistance, skid resistance and sound absorption of factory-mixed hot recycled asphalt mixture. Summary of the invention

[0004] In view of this, the object of the present invention is to provide a factory-mixed hot-regenerated asphalt mixture and a preparation method thereof, so as to solve the problems of stability, fatigue resistance, skid resistance and sound absorption of the factory-mixed hot-regenerated asphalt mixture.

[0005] The factory-mixed hot-regenerated asphalt mixture of the present invention comprises the following components in parts by weight: 80-90 parts of old SBS asphalt mixture, 4-8 parts of asphalt, 10-20 parts of aggregate, 2-6 parts of mineral powder, 1-3 parts of polyvinyl chloride powder, 1-3 parts of warm mix agent, and 1-3 parts of composite regeneration agent; the composite regeneration agent raw materials comprise in parts by weight 90-110 parts of furfural extracted oil, 5-10 parts of triallyl isocyanurate, 2-6 parts of triethoxysilane, 4-10 parts of three-dimensional porous material, 3-8 parts of penetrant, 20-30 parts of toluene-2,4-diisocyanate, 10-20 parts of terminal hydroxyl polybutadiene, 5-12 parts of plasticizer, and 5-10 parts of tackifier;

[0006] Furthermore, the aggregate is a mixture of steel slag and basalt fiber, and the mass ratio of basalt fiber to steel slag is 3:1;

[0007] Further, the penetrant is petroleum ether, and the plasticizer is dioctyl phthalate;

[0008] Furthermore, the viscosity enhancer is petroleum resin, and the three-dimensional porous material is three-dimensional porous fiber or metal material;

[0009] Further, the warm mix agent is Sasobit warm mix agent;

[0010] Furthermore, the raw materials of the mixture include the following components in parts by weight: 85 parts of old SBS asphalt mixture, 6 parts of asphalt, 15 parts of aggregate, 4 parts of mineral powder, 2 parts of polyvinyl chloride powder, 2 parts of warm mix agent, and 2 parts of composite regeneration agent; the raw materials of the composite regeneration agent include 100 parts of furfural extracted oil, 7 parts of triallyl isocyanurate, 4 parts of triethoxysilane, 6 parts of three-dimensional porous material, 6 parts of penetrant, 25 parts of toluene-2,4-diisocyanate, 15 parts of terminal hydroxyl polybutadiene, 8 parts of plasticizer, and 8 parts of viscosity enhancer.

[0011] The present invention also discloses a method for preparing a factory-mixed hot-regenerated asphalt mixture, comprising the following steps:

[0012] S1, mix the old SBS asphalt mixture with the warm mix agent and heat it to 120-130℃

[0013] S2, heating the aggregate to 180-190° C., and then mixing and stirring with the material in step S1;

[0014] S3, mixing the asphalt and the composite regeneration agent and heating them to 150-165°C, then adding and mixing with the materials in step S2, and finally adding polyvinyl chloride powder and mineral powder and stirring, and controlling the discharge temperature to be 150-165°C;

[0015] Furthermore, the preparation method of the composite regeneration agent comprises the following steps:

[0016] a. Mix toluene-2,4-diisocyanate and dibutyltin dilaurate catalyst and heat to 80-100°C under nitrogen protection, then slowly add hydroxyl-terminated polybutadiene to react until the isocyanate group content is constant, and then vacuum distill the product for standby use;

[0017] b. Mix the furfural extracted oil, triallyl isocyanurate, triethoxysilane and toluene diisocyanate evenly, then add the penetrant, plasticizer and tackifier, and finally add the product in step S1 and continue stirring at a temperature of 60-90° C. for 1-4 hours.

[0018] Beneficial effects of the present invention: The factory-mixed hot-regenerated asphalt mixture and the preparation method thereof of the present invention enhance the high-temperature stability, low-temperature stability and water stability of the hot-regenerated asphalt mixture, and have good anti-skid and sound absorption properties. In the application of factory-mixed hot-regenerated asphalt mixture engineering, the amount of milling material can reach more than 85%, saving economic costs. DETAILED DESCRIPTION

[0019] For a better understanding of the present invention, the following examples are provided to further illustrate the present invention, but the present invention is not limited to the following examples.

[0020] In the examples, the experimental methods used are conventional methods unless otherwise specified, and the materials, reagents, etc. used are all commercially available unless otherwise specified.

[0021] The factory-mixed hot-regenerated asphalt mixture of this embodiment comprises the following components in parts by weight: 80-90 parts of old SBS asphalt mixture, 4-8 parts of asphalt, 10-20 parts of aggregate, 2-6 parts of mineral powder, 1-3 parts of polyvinyl chloride powder, 1-3 parts of warm mix agent, and 1-3 parts of composite regeneration agent; the composite regeneration agent raw materials comprise in parts by weight 90-110 parts of furfural extracted oil, 5-10 parts of triallyl isocyanurate, 2-6 parts of triethoxysilane, 4-10 parts of three-dimensional porous material, 3-8 parts of penetrant, 20-30 parts of toluene-2,4-diisocyanate, 10-20 parts of terminal hydroxyl polybutadiene, and plasticizer. 5-12 parts of agent, 5-10 parts of viscosity enhancer; adding polyvinyl chloride powder can strengthen the structural strength of asphalt and enhance the mechanical properties of the mixture; using triallyl isocyanurate can reconnect the broken SBS polymer to form a three-dimensional cross-linked network structure; using viscosity enhancer and permeability agent to work together, and through the diffusion of the permeability agent, the compatibility and anti-aging performance of the regeneration agent are improved, so that the high temperature stability and adhesion of the regenerated asphalt are better; using three-dimensional porous materials to improve the anti-skid and sound absorption of hot regenerated asphalt mixtures, and can significantly improve the high temperature performance, low temperature performance, water stability and anti-cracking performance of the regenerated asphalt mixture. At the same time, the three-dimensional porous material also plays a "bridging" role, which can also improve the anti-aging and fatigue resistance of the asphalt mixture. The use of three-dimensional porous materials can reduce the creep rate of recycled asphalt mixtures, prevent the flow deformation of asphalt, and improve its high-temperature stability; at low temperatures, basalt fiber can greatly increase the dissipated energy ratio of recycled asphalt mixtures, thereby improving the stress relaxation ability of recycled asphalt mixtures. At the same time, triethoxysilane, toluene-2,4-diisocyanate, and terminal hydroxyl polybutadiene are combined to hydrogenate and reduce the aged asphalt and hydroxylate it, achieving the dual effects of chemical repair and physical repair. After hydrogenation and reduction, the strong polar oxygen-containing functional groups (carbonyl, sulfoxide, etc.) in the aged asphalt are converted into weakly polar ethers, esters and a small amount of hydroxyl groups, and toluene diisocyanate further reacts with hydroxyl groups. Hydrogenation and hydroxylate esterification significantly weaken the interaction between the aged asphalt molecules caused by hydrogen bonds, reduce the polarity of the aged asphalt, and thus significantly improve the macroscopic properties of the aged asphalt.

[0022] In this embodiment, the aggregate is a mixture of steel slag and basalt fiber, and the mass ratio is basalt fiber: steel slag = 3:1; 4. The addition of steel slag can slow down the temperature loss inside the mixture, which is conducive to promoting the activation-fusion degree of new and old asphalt. Through the joint action of the regeneration agent and steel slag, the activation degree of old asphalt can be effectively improved, and its fusion with new asphalt can be promoted, thereby improving the high temperature stability, low temperature crack resistance and water stability of the hot regenerated asphalt mixture. Basalt fiber can significantly reduce the creep rate of the regenerated asphalt mixture, prevent the flow deformation of asphalt, and improve its high temperature stability; at low temperatures, basalt fiber can greatly increase the dissipated energy ratio of the regenerated asphalt mixture, which can quickly dissipate the accumulated stress, thereby improving the stress relaxation ability of the regenerated asphalt mixture.

[0023] Preferably, the penetrant is petroleum ether, the plasticizer is dioctyl phthalate; the tackifier is petroleum resin, and the three-dimensional porous material is a three-dimensional porous fiber or a metal material.

[0024] In this embodiment, the warm mix agent is Sasobit warm mix agent; the Sasobit warm mix agent used is provided by Henan Lupeng Transportation Technology Co., Ltd.

[0025] A preferred embodiment is that the mixture raw materials include the following components in parts by weight: 85 parts of old SBS asphalt mixture, 6 parts of asphalt, 15 parts of aggregate, 4 parts of mineral powder, 2 parts of polyvinyl chloride powder, 2 parts of warm mix agent, and 2 parts of composite regeneration agent; the composite regeneration agent raw materials include 100 parts of furfural extracted oil, 7 parts of triallyl isocyanurate, 4 parts of triethoxysilane, 6 parts of three-dimensional porous material, 6 parts of penetrant, 25 parts of toluene-2,4-diisocyanate, 15 parts of terminal hydroxyl polybutadiene, 8 parts of plasticizer, and 8 parts of viscosity enhancer.

[0026] This embodiment also discloses a method for preparing a factory-mixed hot recycled asphalt mixture, comprising the following steps:

[0027] S1, mix the old SBS asphalt mixture with the warm mix agent and heat it to 120-130℃;

[0028] S2, heating the aggregate to 180-190° C., and then mixing and stirring with the material in step S1;

[0029] S3, mixing the asphalt and the composite regeneration agent and heating them to 150-165°C, then adding and mixing with the materials in step S2, and finally adding polyvinyl chloride powder and mineral powder and stirring, and controlling the discharge temperature to be 150-165°C;

[0030] In this embodiment, the preparation method of the composite regeneration agent comprises the following steps:

[0031] a. Mix toluene-2,4-diisocyanate and dibutyltin dilaurate catalyst and heat to 80-100°C under nitrogen protection, then slowly add hydroxyl-terminated polybutadiene to react until the isocyanate group content is constant, and then vacuum distill the product for standby use;

[0032] b. Mix the furfural extracted oil, triallyl isocyanurate, triethoxysilane and toluene diisocyanate evenly, then add the penetrant, plasticizer and tackifier, and finally add the product in step S1 and continue stirring at a temperature of 60-90° C. for 1-4 hours.

[0033] Embodiment 1

[0034] The factory-mixed hot-regenerated asphalt mixture of this embodiment, the mixture raw materials include the following components in parts by weight: 80 parts of old SBS asphalt mixture, 4 parts of asphalt, 10 parts of aggregate, 2 parts of mineral powder, 1 part of polyvinyl chloride powder, 1 part of warm mix agent, and 1 part of composite regeneration agent; the composite regeneration agent raw materials include in parts by weight 90 parts of furfural extracted oil, 5 parts of triallyl isocyanurate, 2 parts of triethoxysilane, 4 parts of three-dimensional porous material, 3 parts of penetrant, 20 parts of toluene-2,4-diisocyanate, 10 parts of terminal hydroxyl polybutadiene, 5 parts of plasticizer, and 5 parts of viscosity enhancer.

[0035] The preparation method comprises the following steps:

[0036] S1, mix the old SBS asphalt mixture with the warm mix agent and heat it to 120℃

[0037] S2, heating the aggregate to 180° C., and then mixing and stirring with the material in step S1;

[0038] S3, mixing the asphalt and the composite regeneration agent and heating them to 150°C, then adding them to the materials in step S2 and mixing them, and finally adding polyvinyl chloride powder and mineral powder and mixing them, and controlling the discharge temperature to be 150°C.

[0039] In this embodiment, the preparation method of the composite regeneration agent comprises the following steps:

[0040] a. Mix toluene-2,4-diisocyanate and dibutyltin dilaurate catalyst and heat to 80°C under nitrogen protection, then slowly add hydroxyl-terminated polybutadiene to react until the isocyanate content is constant, and then vacuum distill the product for standby use;

[0041] b. Mix furfural extracted oil, triallyl isocyanurate, triethoxysilane and toluene diisocyanate evenly, then add penetrant, plasticizer and tackifier, and finally add the product in step S1 and continue stirring at 60° C. for 4 h.

[0042] Embodiment 2

[0043] The factory-mixed hot-regenerated asphalt mixture of this embodiment comprises the following components in parts by weight: 90 parts of old SBS asphalt mixture, 8 parts of asphalt, 20 parts of aggregate, 6 parts of mineral powder, 3 parts of polyvinyl chloride powder, 3 parts of warm mix agent, and 3 parts of composite regeneration agent; the composite regeneration agent raw materials comprise, in parts by weight, 110 parts of furfural extracted oil, 10 parts of triallyl isocyanurate, 6 parts of triethoxysilane, 10 parts of three-dimensional porous material, 8 parts of penetrant, 30 parts of toluene-2,4-diisocyanate, 20 parts of terminal hydroxyl polybutadiene, 12 parts of plasticizer, and 10 parts of viscosity enhancer.

[0044] The preparation method comprises the following steps:

[0045] S1, mix the old SBS asphalt mixture with the warm mix agent and heat it to 130℃

[0046] S2, heating the aggregate to 190° C., and then mixing and stirring with the material in step S1;

[0047] S3, mixing the asphalt and the composite regeneration agent and heating them to 165°C, then adding them to the materials in step S2 and mixing them, and finally adding polyvinyl chloride powder and mineral powder and mixing them, and controlling the discharge temperature to be 165°C.

[0048] In this embodiment, the preparation method of the composite regeneration agent comprises the following steps:

[0049] a. Mix toluene-2,4-diisocyanate and dibutyltin dilaurate catalyst and heat to 100°C under nitrogen protection, then slowly add hydroxyl-terminated polybutadiene to react until the isocyanate group content is constant, and then vacuum distill the product for standby use;

[0050] b. Mix furfural extracted oil, triallyl isocyanurate, triethoxysilane and toluene diisocyanate evenly, then add penetrant, plasticizer and tackifier, and finally add the product in step S1 and continue stirring at 90° C. for 1 h.

[0051] Embodiment 3

[0052] The factory-mixed hot-regenerated asphalt mixture of this embodiment comprises the following components in parts by weight: 80 parts of old SBS asphalt mixture, 8 parts of asphalt, 10 parts of aggregate, 6 parts of mineral powder, 1 part of polyvinyl chloride powder, 3 parts of warm mix agent, and 1 part of composite regeneration agent; the composite regeneration agent raw materials comprise, in parts by weight, 90 parts of furfural extracted oil, 10 parts of triallyl isocyanurate, 2 parts of triethoxysilane, 10 parts of three-dimensional porous material, 3 parts of penetrant, 30 parts of toluene-2,4-diisocyanate, 10 parts of terminal hydroxyl polybutadiene, 12 parts of plasticizer, and 5 parts of viscosity enhancer.

[0053] The preparation method comprises the following steps:

[0054] S1, mix the old SBS asphalt mixture with the warm mix agent and heat it to 125℃

[0055] S2, heating the aggregate to 182° C., and then mixing and stirring with the material in step S1;

[0056] S3, mixing the asphalt and the composite regeneration agent and heating them to 155°C, then adding them to the materials in step S2 and mixing them, and finally adding polyvinyl chloride powder and mineral powder and mixing them, and controlling the discharge temperature to be 155°C.

[0057] In this embodiment, the preparation method of the composite regeneration agent comprises the following steps:

[0058] a. Mix toluene-2,4-diisocyanate and dibutyltin dilaurate catalyst and heat to 90°C under nitrogen protection, then slowly add hydroxyl-terminated polybutadiene to react until the isocyanate group content is constant, and then vacuum distill the product for standby use;

[0059] b. Mix furfural extracted oil, triallyl isocyanurate, triethoxysilane and toluene diisocyanate evenly, then add penetrant, plasticizer and tackifier, and finally add the product in step S1 and continue stirring at 85° C. for 3 h.

[0060] Embodiment 4

[0061] The factory-mixed hot-regenerated asphalt mixture of this embodiment comprises the following components in parts by weight: 88 parts of old SBS asphalt mixture, 5 parts of asphalt, 16 parts of aggregate, 3 parts of mineral powder, 2 parts of polyvinyl chloride powder, 1 part of warm mix agent, and 3 parts of composite regeneration agent; the composite regeneration agent raw materials comprise, in parts by weight, 92 parts of furfural extracted oil, 8 parts of triallyl isocyanurate, 4 parts of triethoxysilane, 5 parts of three-dimensional porous material, 6 parts of penetrant, 23 parts of toluene-2,4-diisocyanate, 18 parts of terminal hydroxyl polybutadiene, 6 parts of plasticizer, and 7 parts of viscosity enhancer.

[0062] The preparation method comprises the following steps:

[0063] S1, mix the old SBS asphalt mixture with the warm mix agent and heat it to 122℃

[0064] S2, heating the aggregate to 184° C., and then mixing and stirring with the material in step S1;

[0065] S3, mixing the asphalt and the composite regeneration agent and heating them to 160°C, then adding them to the materials in step S2 and mixing them, and finally adding polyvinyl chloride powder and mineral powder and mixing them, and controlling the discharge temperature to be 160°C.

[0066] In this embodiment, the preparation method of the composite regeneration agent comprises the following steps:

[0067] a. Mix toluene-2,4-diisocyanate and dibutyltin dilaurate catalyst and heat to 85°C under nitrogen protection, then slowly add hydroxyl-terminated polybutadiene to react until the isocyanate group content is constant, and then vacuum distill the product for standby use;

[0068] b. Mix furfural extracted oil, triallyl isocyanurate, triethoxysilane and toluene diisocyanate evenly, then add penetrant, plasticizer and tackifier, and finally add the product in step S1 and continue stirring at 70° C. for 2.5 h.

[0069] Embodiment 5

[0070] The factory-mixed hot-regenerated asphalt mixture of this embodiment, the mixture raw materials include the following components in parts by weight: 85 parts of old SBS asphalt mixture, 4 parts of asphalt, 20 parts of aggregate, 4 parts of mineral powder, 1.5 parts of polyvinyl chloride powder, 2.5 parts of warm mix agent, and 1 part of composite regeneration agent; the composite regeneration agent raw materials include in parts by weight 100 parts of furfural extracted oil, 6 parts of triallyl isocyanurate, 5 parts of triethoxysilane, 8 parts of three-dimensional porous material, 5 parts of penetrant, 22 parts of toluene-2,4-diisocyanate, 18 parts of terminal hydroxyl polybutadiene, 10 parts of plasticizer, and 8 parts of viscosity enhancer.

[0071] The preparation method comprises the following steps:

[0072] S1, mix the old SBS asphalt mixture with the warm mix agent and heat it to 125℃

[0073] S2, heating the aggregate to 188° C., and then mixing and stirring with the material in step S1;

[0074] S3, mixing the asphalt and the composite regeneration agent and heating them to 1160°C, then adding them to the materials in step S2 and mixing them, and finally adding polyvinyl chloride powder and mineral powder and mixing them, and controlling the discharge temperature to be 160°C.

[0075] In this embodiment, the preparation method of the composite regeneration agent comprises the following steps:

[0076] a. Mix toluene-2,4-diisocyanate and dibutyltin dilaurate catalyst and heat to 95°C under nitrogen protection, then slowly add hydroxyl-terminated polybutadiene to react until the isocyanate group content is constant, and then vacuum distill the product for standby use;

[0077] b. Mix furfural extracted oil, triallyl isocyanurate, triethoxysilane and toluene diisocyanate evenly, then add penetrant, plasticizer and tackifier, and finally add the product in step S1 and continue stirring at 85° C. for 1.5 h.

[0078] Embodiment 6

[0079] The factory-mixed hot-regenerated asphalt mixture of this embodiment includes the following components in parts by weight: 85 parts of old SBS asphalt mixture, 6 parts of asphalt, 15 parts of aggregate, 4 parts of mineral powder, 2 parts of polyvinyl chloride powder, 2 parts of warm mix agent, and 2 parts of composite regeneration agent; the composite regeneration agent raw materials include 100 parts of furfural extracted oil, 7 parts of triallyl isocyanurate, 4 parts of triethoxysilane, 6 parts of three-dimensional porous material, 6 parts of penetrant, 25 parts of toluene-2,4-diisocyanate, 15 parts of terminal hydroxyl polybutadiene, 8 parts of plasticizer, and 8 parts of viscosity enhancer.

[0080] The preparation method comprises the following steps:

[0081] S1, mix the old SBS asphalt mixture with the warm mix agent and heat it to 125℃

[0082] S2, heating the aggregate to 185° C., and then mixing and stirring with the material in step S1;

[0083] S3, mixing the asphalt and the composite regeneration agent and heating them to 155°C, then adding them to the materials in step S2 and mixing them, and finally adding polyvinyl chloride powder and mineral powder and mixing them, and controlling the discharge temperature to be 155°C.

[0084] In this embodiment, the preparation method of the composite regeneration agent comprises the following steps:

[0085] a. Mix toluene-2,4-diisocyanate and dibutyltin dilaurate catalyst and heat to 85°C under nitrogen protection, then slowly add hydroxyl-terminated polybutadiene to react until the isocyanate group content is constant, and then vacuum distill the product for standby use;

[0086] b. Mix furfural extracted oil, triallyl isocyanurate, triethoxysilane and toluene diisocyanate evenly, then add penetrant, plasticizer and tackifier, and finally add the product in step S1 and continue stirring at 85° C. for 2 h.

[0087] In the above embodiment, the penetrant is petroleum ether, the plasticizer is dioctyl phthalate, the tackifier is petroleum resin, the three-dimensional porous material is three-dimensional porous fiber (polyester fiber or polyvinyl alcohol fiber), and the warm-mixing agent is Sasobit warm-mixing agent.

[0088] The hot recycled asphalt mixture of the above embodiment was subjected to the water immersion Marshall test, freeze-thaw splitting test, freeze-thaw splitting test, rutting dynamic stability test, and low-temperature beam bending test according to conventional methods. The test results are as follows:

[0089] project Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Residual stability after immersion in water (%) 98.1 98.9 97.2 97.9 97.8 98.6 Freeze-thaw splitting strength ratio (%) 92.7 94.1 92.6 92.9 90.8 95.1 Dynamic stability (%) 2555 2567 2539 2545 2569 2568 Destructive Strength 13.1 13.88 13.54 11.69 12.15 13.99 Stiffness modulus 3451 3476 3489 3471 3491 3496 Failure strain 2897 2905 2897 2914 2893 2912

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A factory-mixed hot recycled asphalt mixture, characterized by: The raw materials of the mixture include the following components by weight: 80-90 parts of old SBS asphalt mixture, 4-8 parts of asphalt, 10-20 parts of aggregate, 2-6 parts of mineral powder, 1-3 parts of polyvinyl chloride powder, 1-3 parts of warm mix agent, and 1-3 parts of composite regeneration agent; the raw materials of the composite regeneration agent include 90-110 parts of furfural extracted oil, 5-10 parts of triallyl isocyanurate, 2-6 parts of triethoxysilane, 4-10 parts of three-dimensional porous material, 3-8 parts of penetrant, 20-30 parts of toluene-2,4-diisocyanate, 10-20 parts of terminal hydroxyl polybutadiene, 5-12 parts of plasticizer, and 5-10 parts of tackifier.

2. The factory-mixed hot recycled asphalt mixture according to claim 1, characterized in that: The aggregate is a mixture of steel slag and basalt fiber, and the mass ratio of basalt fiber to steel slag is 3:

1.

3. The factory-mixed hot recycled asphalt mixture according to claim 1, characterized in that: The penetrant is petroleum ether, and the plasticizer is dioctyl phthalate.

4. The factory-mixed hot recycled asphalt mixture according to claim 1, characterized in that: The viscosity enhancer is petroleum resin, and the three-dimensional porous material is three-dimensional porous fiber or metal material.

5. The factory-mixed hot recycled asphalt mixture according to claim 1, characterized in that: The warm mix agent is Sasobit warm mix agent.

6. The factory-mixed hot recycled asphalt mixture according to claim 1, characterized in that: The raw materials of the mixture include the following components in parts by weight: 85 parts of old SBS asphalt mixture, 6 parts of asphalt, 15 parts of aggregate, 4 parts of mineral powder, 2 parts of polyvinyl chloride powder, 2 parts of warm mix agent, and 2 parts of composite regeneration agent; the raw materials of the composite regeneration agent include 100 parts of furfural extracted oil, 7 parts of triallyl isocyanurate, 4 parts of triethoxysilane, 6 parts of three-dimensional porous material, 6 parts of penetrant, 25 parts of toluene-2,4-diisocyanate, 15 parts of terminal hydroxyl polybutadiene, 8 parts of plasticizer, and 8 parts of viscosity enhancer.

7. The method for preparing factory-mixed hot recycled asphalt mixture according to claim 1, characterized in that: The following steps are involved: S1, mix the old SBS asphalt mixture with the warm mix agent and heat it to 120-130℃ S2, heating the aggregate to 180-190° C., and then mixing and stirring with the material in step S1; S3, mixing the asphalt and the composite regeneration agent and heating them to 150-165°C, then adding them to the materials in step S2 and mixing them, and finally adding polyvinyl chloride powder and mineral powder and mixing them, and controlling the discharge temperature to be 150-165°C.

8. The method for preparing factory-mixed hot-regenerated asphalt mixture according to claim 7, characterized in that: The preparation method of the composite regeneration agent comprises the following steps: a. Mix toluene-2,4-diisocyanate and dibutyltin dilaurate catalyst and heat to 80-100°C under nitrogen protection, then slowly add hydroxyl-terminated polybutadiene to react until the isocyanate group content is constant, and then vacuum distill the product for standby use; b. Mix the furfural extracted oil, triallyl isocyanurate, triethoxysilane and toluene diisocyanate evenly, then add the penetrant, plasticizer and tackifier, and finally add the product in step S1 and continue stirring at a temperature of 60-90° C. for 1-4 hours.