A pavement aggregate gradation design method based on recycled material cluster gradation reconstruction

Abstract

The present application relates to asphalt pavement design, and discloses a pavement aggregate gradation design method based on the reconstruction of the aggregate gradation of recycled materials, which comprises the following steps: firstly, determining the initial mass proportion of coarse, medium and fine three-grade mixed aggregates according to the initial design gradation curve, and determining the initial mixing amount proportion of recycled materials in the mixed aggregates that meet the road performance requirements; secondly, determining the total mass of the remaining mixed aggregates and the mass of the medium and fine aggregates in the remaining mixed aggregates after the hot mixing and reconstruction of the recycled materials through the hot mixing test and the screening method; thirdly, calculating the gradation reconstruction coefficient according to the gradation change rule before and after the reconstruction of the recycled materials; fourthly, calculating the gradation variation coefficient of the recycled materials of each size range according to the gradation change rule before and after the reconstruction of the recycled materials; and finally, calculating the actual mass proportion of the natural aggregates in the mixed aggregates. The method considers the gradation reconstruction rule and gradation variation characteristics of the agglomerated particles of the recycled materials under the action of temperature and mechanical force in the hot mixing process, so that the actual proportion of the mixed aggregates after mixing is consistent with the initial proportion, and the road performance of the mixed aggregates mixed with the recycled materials is effectively ensured.

Description

TECHNICAL FIELD

[0001] The application relates to a pavement aggregate gradation design method based on reconstruction of reclaimed material agglomerate gradation and relates to the technical field of aggregate design of asphalt pavement. BACKGROUND

[0002] Recycling of reclaimed asphalt pavement (RAP or reclaimed material) is an important way to achieve resource conservation and environmental protection in modern road engineering. Agglomerate particles usually exist in RAP material, which are formed by repeated action of traffic load and long-term environmental influence on asphalt and aggregate in the use process. The agglomerate particles are significantly different from ordinary aggregate in particle size distribution, internal structure and mechanical properties, and are influenced by factors such as processing technology, material source and production source. The proportion of agglomerate particles, internal gradation and asphalt adhesion strength have obvious differences. The main characteristic of the agglomerate particles is that some smaller aggregate particles are cemented by asphalt to form a larger aggregate particle. This structural characteristic causes the gradation to change in the production and construction process of road recycled materials, and the gradation reconstruction phenomenon easily occurs in the mixing, stirring and paving process. If the gradation reconstruction is not considered, the proportion of the agglomerate particles in the RAP material is unknown, and the existence of the agglomerate particles changes the final mix proportion of the mixed aggregate in the pavement mixing process, resulting in a difference from the initial design mix proportion. The more RAP material, the more agglomerate particles, and the greater the influence on the mix proportion of the mixed aggregate, which seriously affects the mechanical properties and durability of the pavement.

[0003] The internal cementing material of the reclaimed material agglomerate is aged asphalt, which is inferior to new asphalt in performance. Not considering the gradation reconstruction means not considering the process of dispersing the aggregate particles in the agglomerate particles into the asphalt mixture, resulting in a difference between the final produced gradation skeleton and the design gradation skeleton. The reconstruction of the agglomerate particles usually produces more fine aggregate by reconstructing the large-diameter agglomerate, and the excess fine aggregate after filling the interstitial space of the skeleton reduces the friction between the skeletons and weakens the crack resistance and water stability of the overall asphalt mixture. After considering the gradation reconstruction of the agglomerate particles, the skeleton structure of the asphalt mixture is not affected by the increase of the fine aggregate after the gradation reconstruction, so that the final gradation is consistent with the design gradation.

[0004] Therefore, it is necessary to provide a pavement aggregate gradation design method based on reconstruction of reclaimed material agglomerate gradation. SUMMARY

[0005] The purpose of the present application is to overcome the problem that the existing mix design method of RAP-containing asphalt mixture does not fully consider that the particle size distribution of RAP clumps is reconstructed due to the separation of fine particles from the clumped particles during mixing and construction, which further affects the performance of the mixture, and proposes a pavement aggregate grading design method based on the reconstruction of the particle size distribution of recycled material clumps, which can improve the grading variation and performance of RAP-containing asphalt mixture.

[0006] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0007] A pavement aggregate grading design method based on the reconstruction of the particle size distribution of recycled material clumps, comprising the following steps:

[0008] Step one: Obtain the initial design grading curve of the pavement mixture aggregate, divide it into three grades of coarse, medium and fine according to the particle size range, and record the initial mass proportion A of each grade of mixture aggregate i ; i represents the coarse, medium and fine three grades of mixture aggregate;

[0009] Step two: According to the road performance test of asphalt mixture, determine the initial mixing amount proportion R of each grade particle size recycled asphalt mixture in the corresponding grade mixture aggregate that meets the road performance requirements i ;

[0010] Step three: Weigh the initial mass M of each grade particle size recycled asphalt mixture i , carry out hot mixing test on each grade particle size recycled asphalt mixture, and obtain the remaining mixture after cooling, and measure the mass M of the remaining mixture under the j level screen by screening method i-j , j represents the medium and fine two grades of remaining mixture; according to M i and M i-j , the grading reconstruction coefficient C of each grade particle size recycled asphalt mixture in the mixing process is calculated i-j ; Repeat the hot mixing test several times to calculate the average value of C i-j ;

[0011] Step four: Define the difference between the mass proportion of each grade particle size recycled asphalt mixture in the clumped state and after hot mixing reconstruction as the grading variation coefficient Ki; according to the grading change rule of each grade particle size recycled asphalt mixture before and after reconstruction and the average value of C i-j , the grading variation coefficient K of each grade particle size recycled asphalt mixture is calculated i ;

[0012] Step five: According to A i obtained in step one, R i obtained in step two and K i obtained in step four, the actual mass proportion q of recycled asphalt mixture in the mixture aggregate after adding recycled asphalt mixture is calculatedi and the adjusted mass proportion p of the natural aggregate i .

[0013] It should be noted that in step one, when dividing the particle size range of the mixed aggregate, the maximum particle size of the design gradation is divided by 1 / 3 and 2 / 3, and then the corresponding particle size range is determined according to the sieve size.

[0014] It should be noted that in step three, the gradation reconstruction coefficient C of each range of particle size of the recycled asphalt mixture in the mixing process i-j is determined according to formula (3.1):

[0015] (3.1);

[0016] In the formula: C i-j is the gradation reconstruction coefficient; M i is the initial mass of each range of particle size of the recycled asphalt mixture; M i-j is the mass of the recycled mixture under the jth screen after hot mixing and reconstruction.

[0017] It should be noted that in step four, the gradation variation coefficient K of each range of particle size of the recycled asphalt mixture i is determined according to formula (4.1)-(4.3):

[0018] (4.1);

[0019] (4.2);

[0020] (4.3);

[0021] In the formula: K 粗 , K 中 , K 细 are the gradation variation coefficients of coarse, medium and fine ranges of particle size of the recycled asphalt mixture, respectively.

[0022] It should be noted that in step five, the actual mass proportion q of the recycled asphalt mixture after gradation reconstruction i is determined according to formula (5.1)-(5.3):

[0023] (5.1);

[0024] (5.2);

[0025] (5.3);

[0026] In the formula: q 粗 , q 中 , q 细The actual mass proportion of the coarse, medium and fine three-grade particle size reclaimed asphalt mixture after gradation reconstruction.

[0027] It should be noted that in step five, the adjusted mass proportion p of the natural aggregate in the mixed aggregate after adding the reclaimed asphalt mixture i Determined according to formula (5.4)-(5.6):

[0028] (5.4);

[0029] (5.5);

[0030] (5.6);

[0031] In the formula: p 粗 , p 中 , p 细 The adjusted mass proportions of the coarse, medium and fine three-grade particle size natural aggregate.

[0032] It should be noted that the above method is applied according to the adjusted mass proportion p i The initial mass proportion A of the reclaimed asphalt mixture i R i , and the pavement aggregate mixing construction is carried out.

[0033] Compared with the prior art, the advantages of the present application are:

[0034] 1) The method of the present application can effectively improve the road performance of the reclaimed asphalt mixture: considering the reconstruction of the agglomerated particle gradation, the overall skeleton and the uniform dispersion of the interface weak points of the mixture can be effectively improved during the construction mixing process, and the road performance of the asphalt mixture is further improved.

[0035] 2) The method of the present application is reasonable and widely applicable: the gradation reconstruction coefficient of RAP material is proposed in the present application, which can directly reflect the variation characteristics of the internal gradation of RAP under the action of temperature and mechanical force during high-temperature mixing, and can be used for RAP materials of different agglomeration rates and different sources. The gradation reconstruction coefficient can effectively adjust RAP materials of different sources and agglomeration rates, solve the problem that the traditional method does not consider the internal gradation reconstruction of RAP agglomerated particles in the design of the reclaimed asphalt mixture with RAP content, and the present application is applicable to RAP materials of different sources.

[0036] 3) The method is simple to operate and has strong implementability: for RAP materials of different sources and agglomeration rates, the gradation reconstruction coefficient of the RAP materials is determined by the mixing test in the method, so that the gradation variation characteristics of the RAP materials in the asphalt mixture can be quickly obtained, the gradation variation of the same batch of RAP materials can be quickly obtained, and the mixture ratio design for the batch of RAP materials can be adjusted, and the method is suitable for RAP materials of different sources and agglomeration rates. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 The design flowchart of the method is shown in the figure;

[0038] Figure 2 The gradation composition schematic diagram of the natural aggregate and the RAP material in the mixed aggregate is shown in the figure;

[0039] Figure 3 The schematic diagram of the RAP material agglomeration particle gradation reconstruction and the natural aggregate ratio adjustment in the mixing process is shown in the figure;

[0040] Figure 4 The schematic diagram of the RAP material agglomeration particle gradation reconstruction and the natural aggregate ratio adjustment in the mixing process is shown in the figure;

[0041] Figure 5 The schematic diagram of the gradation variation coefficient is shown in the figure. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application.

[0043] Embodiment 1;

[0044] Please refer to Figure 1 , the method is implemented according to the SMA-13 gradation design, and the specific process of the method is as follows:

[0045] Step 1: Obtain the initial design gradation curve of the pavement mixed aggregate, divide it into three grades of coarse, medium and fine according to the particle size range, the maximum particle size of the SMA-13 is 16.16 mm, divide the particle size grades according to the positions of 1 / 3 and 2 / 3 of the maximum particle size of the design gradation, 16.16 / 3=5.33, 16.16×(2 / 3)=10.67, determine the particle size grades combined with the commonly used sieve hole sizes, which are 9.5-15 mm, 4.75-9.5 mm and 0-4.75 mm for coarse, medium and fine, respectively, and record the mass proportions of the coarse aggregate (9.5-15 mm) A 粗 , the medium aggregate (4.75-9.5 mm) A 中 , and the fine aggregate (0-4.75 mm) A 细 ;

[0046] Step two: Determine the total percentage of RAP material in the corresponding grade of mixed aggregate in different particle size ranges R by road performance test i (where i = coarse, medium, fine);

[0047] Step three: Respectively weigh 2 kg of each grade of particle size RAP group particles (M i ) in a 130°C mixing pot (i.e. hot mixing test), and after cooling, obtain the remaining aggregate, then sieve the remaining aggregate, with a sieve size of 9.5 mm (corresponding to j = medium) and 4.75 mm (corresponding to j = fine), and after weighing, obtain the mass M i-j of the remaining aggregate under the j level screen, and according to M i and M i-j , calculate the gradation reconstruction coefficient C i-j of each grade of particle size RAP group particles in the mixing process; where j = medium, fine, corresponding to 4.75-9.5 mm and 0-4.75 mm respectively; C i-j includes: C 粗-中 , C 粗-细 and C 中-细 ; repeat the hot mixing test multiple times to calculate the average value of C i-j ; wherein the fine grade RAP group particles can not carry out the hot mixing test;

[0048] Step four: According to the change rule of each grade of particle size of recycled asphalt mixture before and after reconstruction, combined with the average value of the RAP mixing gradation reconstruction coefficient C i-j , calculate the gradation variation coefficient K i of the RAP material; K i includes K 粗 , K 中 and K 细 ;

[0049] Step five: According to the initial mass percentage A i of each grade of mixed aggregate, the initial dosage percentage R i of RAP material and the gradation variation coefficient K i , calculate the actual mass percentage q i of the recycled asphalt mixture in the mixed aggregate after gradation reconstruction and the adjusted mass percentage p i of the natural aggregate after adding the recycled asphalt mixture.

[0050] The above mix design method can be expressed as Table 1:

[0051] .

[0052] Figure 2The figure is a schematic diagram of gradation composition of natural aggregate and RAP material in mixed aggregate. The natural aggregate and RAP material of different particle size have different mixing amount range, but the aggregate of same particle size should be consistent with the initial proportion. Figure 3 The figure is a schematic diagram of particle gradation of RAP material before reconstruction in mixing process. 粗-中 The figure is a schematic diagram of particle gradation of RAP material before reconstruction in mixing process. 粗-细 The figure reflects the amount of coarse particle size RAP material that will be reconstructed. 中-细 The figure reflects the amount of medium particle size RAP material that will be reconstructed. Figure 4 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 粗-中 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 粗-细 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 粗-中 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 粗-细 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 中-细 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 粗-细 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 中-细 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 粗-细 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 中-细 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 粗-细 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 中-细 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C 粗-细 The figure is a schematic diagram of particle gradation reconstruction of RAP material in mixing process and a schematic diagram of natural aggregate proportion adjustment. After the gradation reconstruction, the coarse particle size RAP material is reduced by the amount of C Figure 5 The figure is a schematic diagram of gradation variation coefficient, which reflects the variation process of RAP material.

[0053] In the traditional design method, the RAP material (i.e. recycled asphalt mixture) is added to the natural aggregate as a part of the mixed aggregate as a single particle of ordinary aggregate. However, due to the old aggregate of different particle sizes contained in the agglomerated particles, the RAP material agglomerated particles will be re-graded after hot mixing, which seriously affects the final mixture and road performance of the mixed aggregate. The RAP material agglomerated particles are composed of multiple old aggregate particles and old asphalt cement adhering to the surface of the old aggregate. During the hot mixing process of the mixed aggregate and new asphalt, the old asphalt softens due to heating, and part of the adhered old aggregate particles fall off from the RAP material agglomerated particles during the mixing process to form new aggregate particles. This part of the aggregate particles causes the original design gradation of the mixture skeleton structure to deviate, and the fine aggregate increases and the coarse aggregate decreases, which is the re-gradation phenomenon. After part of the aggregate particles are loose and peeled off, the remaining mixture still maintains the agglomeration, and this part of the agglomerated particles still maintains the agglomeration state after heating and mixing, which indicates that the particles composed of aggregate and asphalt cement are almost not affected by heating and mixing, and the strength of the RAP particles is restored after cooling, which is regarded as a single particle of aggregate. Therefore, in the method of the present application, the old asphalt in the RAP material is fully melted through the hot mixing test, so that the melted old asphalt adheres to a few or a single old aggregate particle and then cools to obtain the remaining mixture (i.e. very small agglomerated particles). Then, the remaining mixture is sieved, and the mass of the sieve residue mixture is determined, and the re-gradation coefficient of the RAP material is calculated according to the mass, which fully reflects the re-gradation phenomenon of the RAP material during the hot mixing process, and is basically consistent with the actual hot mixing construction.

[0054] In the application of the above method, the mass proportion p of each particle size natural aggregate after adjustment i and the initial mass proportion A of the recycled asphalt mixture i R i , the road aggregate mixing construction is carried out.

[0055] Example 2;

[0056] The initial mass proportions of the coarse, medium and fine three particle sizes of the SMA-13 gradation are determined to be 30%, 45% and 25% respectively, and the mass proportions of the recycled asphalt mixture of each particle size are determined to be 60%, 50% and 40% respectively after the initial asphalt mixture performance test. The initial parameters of the gradation are shown in Table 2.

[0057] .

[0058] The coarse and medium particle size aggregates of the recycled asphalt mixture are taken for hot mixing test, and then the coarse particle size aggregate is sieved to determine the re-gradation coefficients C 粗-中 and C 粗-细 ; the medium particle size aggregate is sieved to determine the re-gradation coefficient C 中-细 ; as shown in Table 3.

[0059] .

[0060] After determining the coarse, medium and fine recycled material gradation reconstruction coefficients, the mass of three-grade particle size aggregate is calculated:

[0061] The mass proportion of coarse recycled material after mixing = 18% - 18% x 29% - 18% x 25% = 8.28%;

[0062] The mass proportion of medium recycled material after mixing = 22.5% + 18% x 29% - 22.5% x 42% = 18.27%;

[0063] The mass proportion of fine recycled material after mixing = 10% + 18% x 25% + 22.5% x 42% = 23.95%;

[0064] The mass proportion of coarse natural aggregate = 12% + 18% x 29% + 18% x 25% = 21.72%;

[0065] The mass proportion of medium natural aggregate = 22.5% - 18% x 29% + 22.5% x 42% = 26.73%;

[0066] The mass proportion of fine natural aggregate = 15% - 18% x 25% - 22.5% x 42% = 1.05%.

[0067] The adjusted mass proportions of natural aggregate and recycled material are shown in Table 4.

[0068] .

[0069] When mixing recycled asphalt mixture in subsequent construction, the mass proportions of natural aggregate gradation are p 粗 = 21.72%, p 中 = 26.73%, p 细 = 1.05%; and the mass proportions of recycled asphalt mixture gradation before reconstruction are A 粗 R 粗 = 18%, A 中 R 中 = 22.5%, A 细 R 细=10%; the natural aggregate and the recycled asphalt mixture are mixed according to the above-mentioned proportion, and the skeleton gradation meeting the design requirement can be obtained after hot mixing. When the gradation reconstruction is not considered, the actual mass proportions of the coarse, medium and fine three-grade particle size aggregates in the hot mixing process are 20.28%, 40.77% and 38.95% respectively, compared with the design mass proportions, the coarse-grade particle size aggregate is reduced by 9.72%, the medium-grade particle size aggregate is reduced by 4.23%, and the fine-grade particle size aggregate is increased by 13.95%. Obviously, when the gradation reconstruction is not considered, the actual proportion of the mixed aggregate with RAP after hot mixing is greatly different from the design proportion, the fine particles increase, the friction between aggregates decreases, and the crack resistance and water stability of the asphalt mixture are seriously weakened. On the contrary, after considering the gradation reconstruction, based on the method of the present application, the natural aggregate changes, and the actual final proportion is consistent with the design proportion. The crack resistance and water stability of the asphalt mixture are guaranteed.

[0070] The above merely describes preferred embodiments of the present application, but is not intended to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for designing pavement aggregate gradation based on reconstructed gradation of recycled material, characterized in that, Includes the following steps: Step 1: Obtain the initial design gradation curve of the road aggregate mixture, divide it into three grades (coarse, medium, and fine) according to the particle size range, and record the initial mass percentage (A) of the aggregate mixture in each grade. i ;i represents the three grades of mixed aggregate: coarse, medium, and fine; Step 2: Based on the asphalt mixture road performance test, determine the initial admixture ratio R of each particle size of recycled asphalt mixture that meets the road performance requirements in the corresponding grade of aggregate mixture. i ; Step 3: Weigh the initial mass of each grade of recycled asphalt mixture as M. i Hot-mix tests were conducted on recycled asphalt mixtures of each particle size. After cooling, the remaining mixture was obtained. The mass M of the remaining mixture after sieving under a grade j sieve was measured using the sieve method. i-j j represents the medium and fine grades of the remaining mixture; according to M i and M i-j The gradation reconstruction coefficient C of recycled asphalt mixtures of various particle sizes during the mixing process was calculated. i-j Repeat the hot-mixing experiment multiple times and calculate C. i-j The average value; In step three, the gradation reconstruction coefficient C of recycled asphalt mixtures of different particle sizes during the mixing process is... i-j Determine according to formula (3.1): (3.1)； In the formula: C i-j M is the gradation reconstruction coefficient; i The initial mass of recycled asphalt mixtures of various particle sizes; M i-j The mass of the remaining mixture after hot mixing and reconstruction is the mass of the mixture remaining after sieving through a grade j sieve. Step 4: Define the difference in mass percentage of each particle size of recycled asphalt mixture before and after hot-mix reconstitution as the coefficient of variation Ki; based on the gradation change law of each particle size of recycled asphalt mixture before and after reconstitution and the obtained C i-j Calculate the coefficient of variation K for each particle size of the recycled asphalt mixture based on the average value. i ; In step four, the coefficient of variation K for each particle size of the recycled asphalt mixture is... i Determine according to formulas (4.1) to (4.3): (4.1)； (4.2)； (4.3)； Where: K 粗 K 中 K 细 These are the gradation variation coefficients of recycled asphalt mixtures with coarse, medium, and fine particle sizes, respectively. Step 5: Based on A obtained in Step 1 i The R obtained in step two i K obtained in step four i The actual mass proportion q of recycled asphalt mixture in the aggregate after gradation reconstruction was calculated. i And the adjusted mass percentage of natural aggregates p i .

2. The method for pavement aggregate gradation design based on recycled material agglomeration gradation reconstruction according to claim 1, characterized in that, In step one, when dividing the aggregate into particle size ranges, the aggregate is divided into 1 / 3 and 2 / 3 of the maximum particle size of the design gradation, and then the corresponding particle size range is determined according to the sieve aperture size.

3. The method for pavement aggregate gradation design based on recycled material agglomeration gradation reconstruction according to claim 1, characterized in that, In step five, the actual mass percentage q of the recycled asphalt mixture after gradation reconstruction is... i Determine according to formulas (5.1) to (5.3): (5.1)； (5.2)； (5.3)； In the formula: q 粗 q 中 q 细 These represent the actual mass percentages of recycled asphalt mixtures with coarse, medium, and fine particle sizes after gradation reconstruction.

4. The method for pavement aggregate gradation design based on recycled material agglomeration gradation reconstruction according to claim 1, characterized in that, In step five, the adjusted mass percentage p of natural aggregate in the aggregate mixture after adding recycled asphalt mixture is determined. i Determine according to formulas (5.4) to (5.6): (5.4)； (5.5)； (5.6)； In the formula: p 粗 p 中 p 细 These represent the adjusted mass percentages of natural aggregates in three particle sizes: coarse, medium, and fine.

5. The method for pavement aggregate gradation design based on reconstructed aggregate agglomeration of recycled materials according to any one of claims 1-4, characterized in that, When applying, adjust the mass percentage p of the natural aggregates of each particle size. i Initial mass ratio A of recycled asphalt mixture i R i , to carry out road aggregate mixing construction.

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