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CN-121974601-A - Environment-friendly recycled asphalt concrete and preparation method thereof

CN121974601ACN 121974601 ACN121974601 ACN 121974601ACN-121974601-A

Abstract

The invention belongs to the technical field of concrete, and particularly relates to environment-friendly recycled asphalt concrete and a preparation method thereof. The invention provides environment-friendly recycled asphalt concrete, which comprises, by weight, 100 parts of recycled asphalt mixture RAP, 15-20 parts of asphalt, 4-8 parts of sodium stearate modified basalt fiber, 5-15 parts of HY-102 and octanediamine modified vermiculite nano sheets, and 9-15 parts of polyolefin modifier. The recycled asphalt mixture can save cost, the dispersibility of the basalt fibers in the concrete can be improved by modifying the basalt fibers by sodium stearate, the mechanical property of asphalt concrete is further improved, the dispersibility of the vermiculite nano sheets in the asphalt concrete can be improved by HY-102 and octanediamine modified vermiculite nano sheets, the bonding strength of the vermiculite nano sheets and a base material is enhanced, the mechanical property of the asphalt concrete is enhanced, and the interface property of asphalt and aggregate can be improved by the polyolefin modifier, so that the overall property of the mixture is improved.

Inventors

  • CAI YANCHANG

Assignees

  • 广州致高环保新材料科技有限公司

Dates

Publication Date
20260505
Application Date
20260211

Claims (10)

  1. 1. The environment-friendly recycled asphalt concrete is characterized by comprising the following raw materials in parts by weight: 100 parts of recycled asphalt mixture RAP; 15-20 parts of asphalt; 4-8 parts of sodium stearate modified basalt fiber; 5-15 parts of HY-102 and subelamine modified vermiculite nano sheets; 9-15 parts of polyolefin modifier.
  2. 2. The environment-friendly recycled asphalt concrete of claim 1, wherein the preparation method of the sodium stearate modified basalt fiber comprises the following steps: Adding sodium stearate and basalt fiber into deionized water, stirring, filtering, and then vacuum drying to constant weight to obtain modified basalt fiber.
  3. 3. The environment-friendly recycled asphalt concrete according to claim 1, wherein the mass ratio of basalt fiber to sodium stearate is 100:3-7, the length of the basalt fiber is 6-10 mm, and the length-diameter ratio is 30-50:1.
  4. 4. The environment-friendly recycled asphalt concrete according to claim 2, wherein the stirring condition is that stirring is carried out for 2-4 hours at 55-65 ℃, and the vacuum drying temperature is 50-70 ℃.
  5. 5. The environment-friendly recycled asphalt concrete of claim 1, wherein the preparation method of the HY-102 and octanediamine modified vermiculite nano sheets comprises the following steps: (1) Crushing raw vermiculite ore, sieving, and then placing the vermiculite powder in a muffle furnace for heat treatment to obtain expanded vermiculite; (2) Adding the expanded vermiculite obtained in the step (1) into deionized water, rotating at a speed, performing ultrasonic treatment, standing, taking the upper suspension for solid-liquid separation, and drying to obtain vermiculite nano sheets; (3) Dispersing the vermiculite nano sheet obtained in the step (2) and the titanate coupling agent HY-102 into absolute ethyl alcohol, carrying out ultrasonic treatment, filtering, washing, drying to constant weight, dispersing the mixture and subelamine into deionized water, carrying out stirring reaction, filtering, washing, and drying to constant weight to obtain the modified vermiculite nano sheet.
  6. 6. The environment-friendly recycled asphalt concrete according to claim 5, wherein in the step (1), the vermiculite powder after sieving is 1-3 mm, and the heat treatment condition is that the heat treatment is carried out for 4-6 min at 650-750 ℃.
  7. 7. The environment-friendly recycled asphalt concrete according to claim 5 is characterized in that in the step (2), stirring is carried out for 5-15 min at a rotating speed of 2000-3000 rpm, ultrasonic treatment is carried out for 40-60 min under the condition that ultrasonic power is 200-400W, standing time is 10-14 h, and drying temperature is 70-90 ℃.
  8. 8. The environment-friendly recycled asphalt concrete according to claim 5, wherein in the step (3), the ultrasonic treatment condition is that ultrasonic treatment is carried out for 10-20 min at 35-45 ℃, and the mass ratio of the vermiculite nano sheet, the titanate coupling agent HY-102 and the octanediamine is 10:0.5-0.7:0.1-0.3.
  9. 9. The environment-friendly recycled asphalt concrete according to claim 5, wherein in the step (3), the drying is at 60-80 ℃, and the stirring reaction condition is that the stirring reaction is carried out at 45-55 ℃ for 30-50 min.
  10. 10. The method for preparing the environment-friendly recycled asphalt concrete according to any one of claims 1 to 9, which is characterized by comprising the following steps: (1) Preheating the waste asphalt mixture at 130-140 ℃ for 10-20min to obtain a preheated waste asphalt mixture; (2) Preheating asphalt at 150-170 ℃ for 5-10min, adding a polyolefin modifier, modified basalt fibers and modified vermiculite nano sheets, stirring for 3-5min, and then stirring and mixing with the preheated waste asphalt mixture obtained in the step (1) to obtain the environment-friendly recycled asphalt concrete.

Description

Environment-friendly recycled asphalt concrete and preparation method thereof Technical Field The invention belongs to the technical field of concrete. More particularly, relates to an environment-friendly recycled asphalt concrete and a preparation method thereof. Background Along with the rapid development of highway traffic in China, asphalt concrete pavement has become a main pavement structure form. However, the increasing traffic flow and heavy traffic demands have led to many highways being damaged to varying degrees shortly after they are put into service. Although the pavement performance can be ensured by adopting the brand new high-quality asphalt concrete, the construction cost is greatly increased, and the economic burden of highway maintenance is increased. Therefore, the recycling of the waste asphalt concrete is explored, the maintenance cost can be effectively reduced, the maintenance efficiency is improved, the dependence on natural resources can be reduced, and the method has remarkable social and economic benefits. Aiming at the problems, researchers develop a recycled asphalt concrete technology, and the asphalt recycling technology is to optimally design the recycled asphalt concrete, the new aggregate and the new asphalt through composition. When the mixing amount of the waste asphalt concrete is higher than 30%, a certain amount of regenerant can be added to improve the performance of the mixture, so that the regenerated asphalt concrete material meeting the use requirement is prepared. Polyolefin is used as a high molecular material, and is widely applied to asphalt modification due to excellent oxidation resistance, heat resistance and good mechanical properties. The polyolefin modifier can effectively improve the interface performance of asphalt and aggregate, thereby improving the overall performance of the mixture. CN118993618a discloses a recycled asphalt concrete, a preparation method and application thereof, wherein the recycled asphalt concrete raw material contains SBS modified asphalt, recycled asphalt mixture, aggregate, modified microporous silica, waste mineral oil, guaiac oil, dioctyl phthalate, curing agent and anti-aging agent. The modified microporous silica, the waste mineral oil, the guaiac oil, the dioctyl phthalate, the curing agent and the anti-aging agent are used for regenerating the aged asphalt in the recycled asphalt mixture, and the aggregate and the SBS modified asphalt are used for preparing the recycled asphalt concrete, wherein the proportion of the recycled asphalt mixture in the recycled asphalt concrete is improved to more than 50%, and the recycled asphalt concrete has better high-temperature rutting resistance, low-temperature crack resistance and the like and has higher flexural strength. CN114956671A discloses a preparation method of recycled asphalt concrete, which comprises the following steps of S1, collecting asphalt concrete, conveying the dug old material through a conveying piece after digging the old material on a pavement where the recycled asphalt concrete is required, conveying the dug old material into the collecting piece through the conveying piece, S2, preheating asphalt concrete, preheating the old material through a preheating cylinder, then mixing a regenerant with the preheated old material, further softening the old material asphalt, and after softening, fully mixing the processed old material asphalt and the new material asphalt through heating and stirring the new asphalt, fully regenerating asphalt in the old material, recovering original performance, ensuring quality of a recycled asphalt mixture, and avoiding poor quality of asphalt caused by the fact that the new asphalt and the old material cannot be fully mixed in the existing preparation method. CN105837105A discloses a fiber composite recycled asphalt concrete, which is prepared from, by weight, 30 parts of 0-5mm recycled asphalt concrete RAP, 25 parts of 5-10mm recycled asphalt concrete RAP, 28 parts of 10-30mm recycled asphalt concrete RAP, 15 parts of 10-30mm new aggregate, 2 parts of mineral powder, 1.5 parts of cement, 4 parts of emulsified asphalt, 1 part of a regenerant, and 1.2 parts of glass fiber. By adding the glass fiber, the length is 6mm, the material performance of the cold-recycled mixture is improved, the material performance is obviously higher than that of other fibers, the dispersing effect of the special fiber in the cold-recycled mixture is obviously better than that of the other fibers, and the recycled mixture is smoothly discharged. The fiber composite recycled concrete material provided by the invention has the advantages that the performance is obviously better than the standard requirement, the tensile property, namely the splitting strength, of the mixture is improved, the cracking resistance of the material is better, the reflection crack resistance is stronger, the material is denser, the water loss resistance is stronger, and the dur