Plant-mixed warm regenerated asphalt mixture and preparation method thereof

1. A preparation method of a plant-mixed warm regenerated asphalt mixture, comprising the following steps of:

(1) preparing a RAP material, an aggregate, a mineral powder, a new asphalt and a regenerant with a total mass percentage of 100%, wherein the aggregate is obtained by screening aggregates with four groups of particle sizes, the first group of particle sizes is less than 2.36 mm; the second group of particle sizes is 2.36 to 4.75 mm; the third group of particle sizes is more than 4.75 to 9.5 mm; and the fourth group of particle sizes is more than 9.5 to 16.0 mm;

(2) heating and stirring the RAP material, adding the regenerant, and then continuing to heat and stir, wherein the regenerant comprises a density of 1.017 g/cm 3 at 20° C.; a flash point of 259.5° C.; a kinematic viscosity of 60000 mm 2 /s at 60° C.; a water content (v/v) of 0.13%; an aromatic content (m) of 86.21%; a resin, asphaltene content (m) of 11.01%; and a furfural content of 0.11 mg/kg;

(3) placing a product of step (2) in a development bin for development, wherein a development temperature is 40° C. to 150° C., and a development time is 0.5 h to 6 h;

(4) mixing, heating and stirring a product of step (3) with the aggregate; and

(5) mixing and heating a product of step (4) with the asphalt, adding the mineral powder, stirring, and placing a mixture comprising the asphalt and the mineral powder in a mold.

2. A preparation method of a plant-mixed warm regenerated asphalt mixture, comprising following steps of:

(1) preparing an RAP material, an aggregate, a mineral powder, an asphalt and a regenerant with a total mass percentage of 100%, wherein the aggregate is obtained by screening aggregates with four groups of particle sizes, the first group of particle sizes is less than 2.36 mm; the second group of particle sizes is 2.36 to 4.75 mm; the third group of particle sizes is more than 4.75 to 9.5 mm; and the fourth group of particle sizes is more than 9.5 to 16.0 mm;

(2) mixing and stirring the RAP material and the aggregate which are respectively heated;

(3) adding the regenerant and the asphalt into a product of step (2), and mixing, heating and stirring, wherein the regenerant comprises a density of 1.017 g/cm 3 at 20° C.; a flash point of 259.5° C.; a kinematic viscosity of 60000 mm 2 /s at 60° C.; a water content (v/v) of 0.13%; an aromatic content (m) of 86.21%; a resin, asphaltene content (m) of 11.01%; and a furfural content of 0.11 mg/kg;

(4) adding the mineral powder into a product of step (3), and mixing and stirring; and

(5) placing a product of step (4) in a development bin for development, and then taking out of the bin for molding, wherein a development temperature is 40° C. to 170° C., and a development time is 0.5 h to 6 h.

3. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 1 , wherein the development bin comprises a storage bin, and a stirrer and a heater arranged therein, a volume of the storage bin is 1 to 5000 tons, and a heating method of a heater is one of a heat-transfer oil, an electric heating, or flue discharges of an asphalt mixing plant.

4. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 1 , wherein the RAP material is 20 to 85%, the new aggregate is 10 to 70%, the mineral powder is 0.9 to 8%, the new asphalt is 0.5 to 5% and the regenerant is 0.21 to 0.5% by the mass percentage.

5. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 1 , wherein in step (2), a temperature of the heating of the RAP material is 70 to 160° C., and a time of the stirring is 5 to 10 s.

6. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 1 , wherein in step (2), after the regenerant is added, a temperature of the heating is 40 to 120° C., and a time of the stirring is 15 to 25 s.

7. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 1 , wherein in step (4), a temperature of the heating is 90 to 190° C., and a time of the stirring is 10 to 15 s.

8. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 1 , wherein in step (5), a temperature of the heating is 60 to 160° C., and a time of the stirring is 15 to 25 s.

9. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 2 , wherein in step (2), a temperature of the heating of the RAP material is 80 to 170° C., a temperature of the heating of the aggregate is 90 to 190° C., and a time of the stirring is 15 to 25 s.

10. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 2 , wherein in step (3), a temperature of the heating is 40 to 120° C., and a time of the stirring is 15 to 30 s.

11. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 2 , wherein in step (4), a time of the stirring is 10 to 20 s.

12. A plant-mixed warm regenerated asphalt mixture prepared by the preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 1 .

13. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 2 , wherein the development bin comprises a storage bin, and a stirrer and a heater arranged therein, a volume of the storage bin is 1 to 5000 tons, and a heating method of a heater is one of a heat-transfer oil, an electric heating, or flue discharges of an asphalt mixing plant.

14. The preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 2 , wherein the RAP material is 20 to 85%, the aggregate is 10 to 70%, the mineral powder is 0 to 8%, the asphalt is 0.5 to 5% and the regenerant is 0 to 0.5% by the mass percentage.

15. A plant-mixed warm regenerated asphalt mixture prepared by the preparation method of the plant-mixed warm regenerated asphalt mixture according to claim 2 .