Recycled cement stabilized macadam base course materials and cement stabilized macadam base course

Abstract

The present invention discloses a re-mixed recycled cement stabilized macadam base material and a cement stabilized macadam base, belonging to the field of road engineering. The cement stabilized macadam base material includes a skeleton aggregate, a recycled aggregate interfacial treatment agent and a recycled powder composite filler. The skeleton aggregate includes recycled aggregates. The recycled aggregate interfacial treatment agent is composed of cement, slaked lime, vitrified microspheres and a powder moisturizer. The recycled powder composite filler is composed of a main material and an additive. The main material is composed of recycled powder, fine aggregate and cement, and the weight ratio of the recycled powder, the fine aggregate and the cement is (55-65):(20-40):(10-15). Compared with the prior art, by adopting a special grading and construction process, the present invention can improve the dry shrinkage and temperature shrinkage properties of the water-stabilized macadam base, reduce the transverse cracks of the semi-rigid base, and improve the service life of the pavement structure, and has good popularization and application value.

Description

Technical Field

[0001] The present invention relates to the field of road engineering, and particularly provides a remixing recycled cement stabilized macadam base material and a cement stabilized macadam base. Background Art

[0002] At present, most existing roads use asphalt pavements. During the construction of asphalt pavements, due to excessive powder in fine aggregates, the mixing plant will generate too much waste powder, which is also called recycled powder. With the improvement of environmental awareness, the amount of high-quality stone materials available to construction units is decreasing, and the dust content in the fine aggregates used is increasing, resulting in a very considerable amount of recycled powder generated by each mixing plant.

[0003] The following methods are mostly used to treat recycled powder in the prior art:

[0004] (1) Simple landfill, dumping or paid treatment. With the improvement of environmental awareness, this method has been gradually replaced;

[0005] (2) Solidification treatment, which is difficult to achieve ideal performance. The main reason is that the recycled powder is unstable, and the properties of the recycled powder in each batch of materials are different. Moreover, the particle and composition of the recycled powder are relatively close to silt or sandy soil, and the particles of the material are extremely fine. There is still a blank for high-quality and stable solidification methods for recycled powder;

[0006] (3) Some domestic scholars have also tried to use recycled powder in cement stabilized soil or cement concrete. However, using it in cement stabilized soil is a low-value utilization with low added value. Using it in cement concrete has a great impact on its performance, and the admixing amount is extremely low, so it has not been widely promoted on a large scale. Summary of the Invention

[0007] In view of the above deficiencies in the prior art, the present invention provides a remixing recycled cement stabilized macadam base material, which can achieve a large proportion of admixing of recycled powder.

[0008] A further technical task of the present invention is to provide a remixing recycled cement stabilized macadam base paved with the above material.

[0009] The technical solution adopted by the present invention to solve its technical problems is: the remixing recycled cement stabilized macadam base material is characterized by including a skeleton aggregate, a recycled aggregate interfacial treatment agent, and a recycled powder composite filler. The skeleton aggregate includes recycled aggregates. The recycled aggregate interfacial treatment agent is composed of cement, slaked lime, vitrified microspheres, and a powder moisturizer. The recycled powder composite filler is composed of a main material and an additive. The main material is composed of recycled powder, fine aggregate, and cement, and the weight ratio of recycled powder, fine aggregate, and cement is (50 - 70):(20 - 40):(10 - 15).

[0010] Preferably, the mass ratio relationship between the recycled powder composite filler and the skeleton aggregate is determined according to the following method:

[0011] (1) Calculate the mass ratio A of the recycled powder composite filler to the skeleton aggregate according to formula (I) 1

[0012] A 1 =(1 - ρ 骨捣 / ρ 骨理 ) × ρ 粉湿 / ρ 骨捣 Formula (I)

[0013] Where: ρ 骨捣 is the compacted density of the skeleton aggregate;

[0014] ρ 骨理 is the theoretical density of the skeleton aggregate;

[0015] ρ 粉湿 is the wet density corresponding to the maximum dry density of the recycled powder composite filler under heavy compaction conditions;

[0016] (2) Experimentally verify the mass ratio of the recycled powder composite filler to the skeleton aggregate to obtain the mass ratio A 2

[0017] Respectively carry out heavy compaction tests on the recycled powder composite filler and the skeleton aggregate according to A 1 ×80%, A 1 ×90%, A 1 ×100%, A 1 ×110%, A 1 ×120% to determine the optimal mass ratio A through the maximum dry density 2 ;

[0018] (3) Calculate the mass ratio A of the recycled powder composite filler to the skeleton aggregate according to formula (II) 3 :

[0019] A 3 =(A 1 +A 2 ) / 2 Formula (II).

[0020] In the present invention, the aggregate is mainly used to provide skeleton support.

[0021] Preferably, the grading range of the skeleton aggregate is as follows: the passing rate of the standard sieve hole of 37.5 mm is 100%; the passing rate range of the standard sieve hole of 31.5 mm is 80 - 100%; the passing rate range of the standard sieve hole of 26.5 mm is 30 - 60%; the passing rate range of the standard sieve hole of 19 mm is 0 - 10%. Within this grading range, the aggregate material can not only provide skeleton support for the crushed stone base course, but also provide the best mineral aggregate voids, ensuring the support strength while maximizing the utilization efficiency of the recycled powder.

[0022] Preferably, the skeleton aggregate can be 100% new aggregate or 100% recycled aggregate, as long as it can meet the grading range requirements of the above-mentioned skeleton aggregate.

[0023] The recycled aggregate is obtained by processing road water stable milling materials or water stable crushing materials, which are milling materials or crushing materials with a particle size of 19 - 37.5 mm.

[0024] Preferably, the skeleton aggregate can also be composed of recycled aggregate and new aggregate, with the recycled aggregate as the main component. By adding an appropriate amount of new aggregate, the synthesized grading can meet the grading range requirements of the above-mentioned skeleton aggregate. The weight ratio of the recycled aggregate to the new aggregate can be (60 - 80):(20 - 40), preferably (65 - 75):(25 - 35).

[0025] Preferably, the mass ratio of the recycled aggregate interface treatment agent to the skeleton aggregate is (1 - 3):100, and particularly preferably (1.5 - 2):100.

[0026] The main function of the recycled aggregate interface treatment agent described in the present invention is to improve the interface characteristics of the water stable milling material in the skeleton aggregate, enhance its bonding effect, and also enable the paved skeleton structure to have a certain strength, thereby providing a hard construction interface for the paving of the recycled powder composite filler.

[0027] Preferably, the weight ratio of each raw material of the recycled aggregate interface treatment agent is as follows:

[0028]

[0029] Particularly preferably:

[0030]

[0031] The hydrated lime powder is used to form strength, improve the bonding characteristics of the interface, and the lime forms strength slowly, has small shrinkage, and has the effect of improving the bonding characteristics between asphalt. The fineness is preferably 100 - 200 mesh.

[0032] The vitrified microspheres are mainly used to improve the density and durability of the binder, as well as the fluidity and coating ability of the binder. Preferably, those with a fineness less than 1 micron account for 80-90% (by mass percentage), the average particle size is 0.1-0.15 microns, and the specific surface area is 20-30 m² / g.

[0033] The powder moisturizer, preferably polyacrylamide, mainly functions to increase the consistency and stability of the interfacial treatment agent. After the interfacial treatment agent is mixed with the recycled aggregate, it reduces the loss of surface moisture and acts as a water retention agent.

[0034] The recycled powder composite filler of the present invention mainly forms a framework-dense cement stabilized macadam material with the framework aggregate through on-site remixing. The recycled powder composite filler fully fills the voids formed by the framework aggregate and bonds the framework aggregate into a whole.

[0035] Preferably, the weight ratio of the recycled powder, fine aggregate, and cement in the main material of the recycled powder composite filler is (55-65):(25-30):(11-13).

[0036] Preferably, the additive of the recycled powder composite filler is a water reducing agent and / or an expansion agent.

[0037] The water reducing agent is a naphthalene-based water reducing agent or a polycarboxylate water reducing agent, and the dosage accounts for 0.2-1.0% of the mass of the main material of the recycled powder composite filler.

[0038] The expansion agent is a UEA series expansion agent, and the dosage accounts for 1%-2% of the mass of the main material of the recycled powder composite filler.

[0039] Preferably, the fine aggregate in the recycled powder composite filler is manufactured sand or river sand with a particle size of 3 mm - 6 mm. The dosage of the fine aggregate is 30%-40% of the total mass of the recycled powder composite filler, and the gradation meets the following requirements:

[0040] The passing rate of the standard sieve hole of 9.5 mm is 100%; the passing rate range of the standard sieve hole of 4.75 mm is 90-100%; the passing rate range of the standard sieve hole of 2.36 mm is 0-10%; the passing rate range of the standard sieve hole of 0.075 mm is 0-2%. Within this gradation range, the fine aggregate can not only increase the fluidity of the system during mixing and the strength of the recycled powder composite filler, but also, since the fine aggregate is coarser than the recycled powder particles, its role is similar to that of a micro mixer, which can improve the mixing performance of the recycled powder composite filler.

[0041] The remixing recycled cement stabilized macadam base layer is characterized by being paved with the base layer material of the present invention and includes the following processes:

[0042] S1. Mix the skeletal aggregate, interfacial treatment agent, and appropriate amount of water evenly according to a certain ratio, and obtain a skeletal structure through paving, leveling, compaction, and curing.

[0043] S2. Mix the recycled powder composite filler and appropriate amount of water evenly according to a ratio, and spread it on the surface of the skeletal structure after curing.

[0044] S3. Re-mix the recycled powder composite filler and the skeletal aggregate on-site, and complete the paving of the crushed stone base after compaction.

[0045] Preferably, after the skeletal aggregate, interfacial treatment agent, and water in step S1 are mixed evenly, they are paved and leveled to an appropriate height, then vibrated and compacted 2 - 3 times with a single-drum roller, and a double-drum roller is used to eliminate excessive compaction marks on the surface, and moisturizing and curing for 2 - 3 days to obtain a skeletal structure. The unconfined compressive strength of the specimens of the skeletal structure cured indoors for 7 days is not less than 1.5 MPa.

[0046] Preferably, in step S1, the amount of water used is to ensure that the materials are not dry and do not flow slurry, and the interfacial treatment agent is evenly coated on the skeletal aggregate. The proportion of water is generally 1% - 3% of the mass of the skeletal aggregate. The optimal water consumption of the skeletal aggregate is determined by the critical state where the recycled aggregate does not flow slurry after ramming.

[0047] Preferably, in step S2, the mixing water consumption is determined by increasing the optimal water consumption determined by the indoor heavy compaction test by 1%. After the recycled powder composite filler and appropriate amount of water are mixed evenly, a recycled powder composite filler specimen is prepared by the static pressure forming method of the cement stabilized crushed stone base. The 7-day unconfined compressive strength of the specimen is 12 - 16 MPa.

[0048] Compared with the prior art, the re-mixed recycled cement stabilized crushed stone base material of the present invention has the following prominent beneficial effects:

[0049] (1) It can make the most of waste materials. The main material of the coarse aggregate in the present invention is the water stable milled material or water stable crushed material, and the main component of the recycled powder composite filler is the recycled powder from the asphalt mixing plant. Both of them belong to waste resources that need to be treated. The present invention uses these materials in the construction of the water stable crushed stone base of the road, achieving high-value utilization of resource recycling;

[0050] (2) The treatment efficiency of the recycled powder is high. The relative dosage of the recycled powder in the present invention is high. In the prior art, the dosage of the recycled powder in the water stable base is generally about 5%. Calculated according to the mass ratio of the recycled powder composite filler to the composite skeletal aggregate of 0.378:1 and the recycled powder accounting for 60% in the recycled powder composite filler in the present invention, the recycled powder accounts for about 16% of the mass of the whole system, and its dosage is more than 3 times that of the conventional use method of the recycled powder, realizing a qualitative leap in recycling;

[0051] (3) The cement stabilized macadam base material of the present invention belongs to the framework dense structure. Since there is no material with intermediate particle size, the mixture has high strength, strong overall anti-cracking ability, and is not prone to thermal shrinkage and dry shrinkage. The shrinkage characteristics of the recycled powder composite filler are controlled by an expansive agent (UEA series expansive agent), so that the water stable macadam of the present invention can be used for the semi-rigid base of high-grade roads, thus generating higher economic benefits;

[0052] (4) The construction technology of the cement stabilized macadam base of the present invention belongs to the step-by-step construction method, and has the following characteristics: ① The framework aggregate is paved after being mixed, and a structural layer with a certain strength can be formed after rolling and curing, which is convenient for the paver and the material truck to walk on it. Otherwise, the paver cannot work on it for a long time, which is likely to cause the engine to overheat; ② After being mixed with the interfacial treatment agent, the surface characteristics of the recycled aggregate are changed, making it better adhere to the fine recycled powder. Moreover, the step-by-step construction of the framework aggregate and the recycled powder composite filler can solve the segregation problem during the construction process. Since the content of the recycled powder in the present invention is high, there is an essential difference from the traditional water stable materials. If the conventional construction method is used, segregation is likely to occur.

[0053] (5) The design method of the framework aggregate and the recycled powder composite filler of the present invention is based on the heavy compaction test method, realizing the combination of theoretical calculation and on-site conditions, and can effectively guide practice through verification by physical projects. Detailed implementation mode

[0054] The present invention will be further described below in conjunction with specific embodiments, but it is not limited to the present invention.

[0055] Embodiment:

[0056]

Raw materials

[0057] Framework aggregate: It is composed of water stable milled material and new aggregate. The material ratio and gradation are shown in Table 1. The water stable milled material and the new aggregate are air-dried and mixed evenly according to the ratio to prepare the framework aggregate.

[0058] Recycled aggregate interfacial treatment agent (optimal): It is composed of cement, slaked lime, vitrified microspheres, and powder moisturizer, as shown in Table 2 in detail. The cement, slaked lime, vitrified microspheres, and moisturizer are mixed evenly through dry mortar equipment according to the corresponding ratio to obtain the recycled aggregate interfacial treatment agent.

[0059] Recycled powder composite filler (optimal): It is composed of recycled powder, fine aggregate, cement, water reducing agent, and expansive agent, as shown in Table 3 in detail. The recycled powder, fine aggregate, cement, water reducing agent, and agent are mixed evenly through a stabilized soil mixing equipment to obtain the recycled powder composite filler.

[0060] In this embodiment,

[0061] The cement used is ordinary Portland cement;

[0062] The slaked lime has a fineness of 100 - 200 mesh;

[0063] For the vitrified microspheres, those with a fineness less than 1 μm account for 80 - 90% (by mass percentage), the average particle size is 0.1 - 0.15 μm, and the specific surface area is 20 - 30 ㎡ / g;

[0064] The powder moisturizer used is polyacrylamide;

[0065] The water - reducing agent used is a naphthalene - based water - reducing agent;

[0066] The expansive agent used is UEA expansive agent.

[0067] The fine aggregate used is river sand with a particle size of 3 mm - 6 mm, and its gradation meets the requirements of Table 4.

[0068] Table 1 Specific - gradation recycled aggregate

[0069]

[0070] Table 2 Interface treatment agent

[0071]

[0072] Table 3 Recycled powder composite filler

[0073] Example 1 (optimal) Example 2 Example 3 Example 4 Example 5 Example 6 Recycled powder (Kg) 60 88 80 60 60 60 Fine aggregate (Kg) 28 0 0 28 28 28 Cement (Kg) 12 12 20 12 12 12 Water reducing agent (Kg) 0.8 0.8 1.0 0 1.0 0 Expansive agent (kg) 1.5 1.5 1.5 1.5 0 0

[0074] Table 4 Fine - aggregate gradation

[0075]

[0076]

Mixture ratio design

[0077] 1. Calculation method for the mass ratio relationship between recycled powder composite filler and skeleton aggregate:

[0078] (1) Calculate the mass A of recycled powder composite filler and skeleton aggregate 1

[0079] ① Determine the compacted relative density ρ of the skeleton aggregate in Table 1 according to the aggregate compaction density test method 骨捣 , and ρ can be obtained 骨捣 = 1.842, and determine its theoretical relative density ρ according to the aggregate surface - dry method 骨理 , and ρ can be obtained 骨理 = 2.640.

[0080] Determine the optimum moisture content of the recycled powder composite filler under the heavy compaction condition to be 13% according to the water - stable macadam test method, and the relative wet density ρ corresponding to the maximum dry density 粉湿 , and ρ can be obtained粉湿 = 2.198.

[0081] ② Calculate the theoretical mass ratio A of the recycled powder composite filler to the skeleton aggregate 1

[0082] A 1 = (1 - ρ 骨捣 / ρ 骨理 ) × ρ 粉湿 / ρ 骨捣

[0083] = (1 - 1.842 / 2.64) × 2.198 / 1.842 = 0.36

[0084] (2) Test and verify the theoretical mass ratio A of the recycled powder composite filler to the skeleton aggregate 1 , and obtain the measured mass ratio A 2

[0085] Conduct heavy compaction tests on the mass ratios of the recycled powder composite filler to the skeleton aggregate according to A 1 × 80%, A 1 × 90%, A 1 × 100%, A 1 × 110%, A 1 × 120% respectively, and obtain the dry densities under different mass ratios (see Table 4).

[0086] Table 4 Dry density test results

[0087] Weight ratio <![CDATA[A 1 ×80%]]> <![CDATA[A 1 × 90%]]> <![CDATA[A 1 ×100%]]> <![CDATA[A 1 × 110%]]> <![CDATA[A 1 ×120%]]> Dry density 2.312 2.388 2.411 2.453 2.433

[0088] It can be seen that when the mass ratio is A 1 × 110%, the maximum dry density of the mixture is 2.453, then A 2 = 0.396;

[0089] (3) Calculate the optimal mass ratio A of the recycled powder composite filler to the skeleton aggregate 3

[0090] A 3 = (A 1 + A 2 ) / 2 = (0.36 + 0.396) / 2 = 0.378

[0091] In this embodiment, the optimal mass ratio of the recycled powder composite filler to the skeleton aggregate is 0.378:1.

[0092] 2. The mass ratio of the skeleton aggregate to the interface treatment agent is 100:1.5.

[0093]

Cement stabilized macadam base paving

[0094] 1. Skeleton Structure Pavement

[0095] S11. Mix the skeleton aggregate, interface treatment agent, and water proportionally through a stabilized soil mixing equipment. The amount of water used ensures that the materials are neither dry nor flowing. The interface treatment agent is evenly coated on the skeleton aggregate. The optimal water consumption of the skeleton aggregate is determined based on the critical state where the recycled aggregate does not flow after ramming. Different interface treatment agents result in varying water addition amounts in different examples. See Table 5 for details.

[0096] S12. Transport the above - mixed materials to the site. Use an excavator for paving and a grader to level them to an appropriate height. Then, vibrate and compact them 2 times with a single - drum roller, and use a double - drum roller to eliminate excessive compaction marks on the surface. The paved skeleton structure is maintained moist for 2 days.

[0097] The unconfined compressive strength of the specimens of the obtained skeleton structure cured indoors for 7 days is shown in Table 5:

[0098] Table 5 7 - day Indoor Test

[0099]

[0100] It can be seen from the above tests that the difference between Example 1 and Example 2 lies in the addition of lime. After the addition of lime, the water demand of the system is significantly reduced. For water - stable waste materials, the addition of lime can better handle the interface problems of the materials, thereby improving their strength. Compared with Example 2 and Example 3, it mainly reflects the role of expanded glass microspheres. The reduction of expanded glass microspheres further increases the water demand of the system, thus affecting the later - stage performance of the materials. Example 4 is a scheme using only lime, and Example 5 is a scheme using only microspheres. Both schemes show that using any one of these materials alone cannot achieve the expected effect, and the participation of cement materials is necessary to meet the requirements. Example 6 is to remove expanded glass microspheres from the optimal system. It can be seen that the water demand of its system increases, resulting in a decrease in the strength of the system. Example 7 reflects the role of the moisturizer. The test shows that the strength is basically the same as that of Example 6, but in actual production, the role of the moisturizer is more significant. It can effectively improve the workability of the system during construction. The surface of the aggregate is not easily dried, and the curing strength of the cement is higher. However, due to the constant temperature and humidity in the indoor test, it is difficult to reflect its role. The control group, Example 8, reflects the scheme of using all cement, and obviously the system effect is not ideal.

[0101] 2. Comprehensive Performance of Recycled Powder Composite Filler

[0102] S21. Use a stabilized soil mixing equipment to mix the recycled powder composite filler and water proportionally. The water consumption for mixing is determined by increasing the optimal water consumption determined by the indoor heavy compaction test by 1%, and measure its strength and dry shrinkage coefficient. The results are shown in Table 6:

[0103] Table 6 Performance of Recycled Powder Composite Filler

[0104] Example 1 (optimal) Example 2 Example 3 Example 4 Example 5 Example 6 External water content (mass ratio, %) 8.6 12.3 14.8 11.8 8.6 11.7 Unconfined compressive strength, MPa 13.5 8.8 11.7 10.4 13.4 11.0 <![CDATA[7d drying shrinkage coefficient, ×10 -4 > 31 44 41 35 52 56

[0105] It can be seen from the above data that compared with Example 2, in Example 1, fine aggregate is mainly used. The use of fine aggregate can significantly reduce the water consumption of the system, thereby increasing the strength of the system, and the dry shrinkage coefficient is significantly reduced. Compared with Example 2, the cement dosage is increased in Example 3. Although the strength of the system is improved to a certain extent with the increase of cement dosage, due to the lack of fine aggregate, its strength and dry shrinkage performance cannot be effectively controlled. Compared with Example 1, no water reducer is added in Example 4, resulting in an increase in the water demand of the system and a decrease in strength; compared with Example 1, no expansion agent is added in Example 5. Although the difference in water demand and strength is not significant, a large change in the dry shrinkage coefficient occurs, resulting in the system being more prone to cracking. Compared with Example 1, no water reducer and expansion agent are used in Example 6, resulting in an increase in water demand, a decrease in the strength of the system, and an increase in the dry shrinkage coefficient, not meeting the requirements.

[0106] S22. Spread the mixed recycled powder composite filler on the surface of the skeleton aggregate that has completed curing according to the mass ratio A 3 = 0.378.

[0107] S3. Strength of Recycled Powder Composite Filler and Skeleton Aggregate

[0108] Use an in-situ recycling machine to remix the recycled powder composite filler and the skeleton aggregate on-site, and then use a single-drum roller and a tire roller to complete compaction. Mix the skeleton aggregate with the recycled powder composite filler in Examples 1 - 6 respectively, and the strength changes are shown in Table 7:

[0109] Table 7 Performance of Recycled Powder Composite Filler and Skeleton Aggregate

[0110] Example 1 (optimal) Example 2 Example 3 Example 4 Example 5 Example 6 Recycled powder (Kg) 60 88 80 60 60 60 Fine aggregate (Kg) 28 0 0 28 28 28 Cement (Kg) 12 12 20 12 12 12 Water reducing agent (Kg) 0.8 0.8 1.0 0 1.0 0 Expansive agent (kg) 1.5 1.5 1.5 1.5 0 0 Maximum dry density 2.263 2.212 2.210 2.232 2.261 2.241 Unconfined compressive strength, MPa 5.2 3.2 3.4 4.3 5.0 4.1 <![CDATA[7d drying shrinkage coefficient, ×10 -4 > 21 34 38 36 42 44

[0111] From the analysis of the above test results, the strength of the compound of the recycled powder composite filler and the skeleton aggregate follows the same variation law as the performance of the recycled powder composite filler, and it plays an important role in the influence on the material performance.

[0112] According to the optimal mix ratio of cement-stabilized macadam, the usage amount of recycled powder per unit volume is close to 16% of the total mass, which is nearly 3 times higher than the conventional utilization rate of 5%, and can consume a large amount of recycled powder, reducing environmental pressure.

[0113] The above-described embodiments are only relatively preferred specific implementation manners of the present invention, and the general changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. Re-mixed recycled cement stabilized macadam base course material, Characterized in that: It includes skeleton aggregate, recycled aggregate interface treatment agent and recycled powder composite filler, and the mass ratio of the recycled powder composite filler to the skeleton aggregate is 0.378:1; The skeleton aggregate includes recycled aggregate, The recycled aggregate interface treatment agent is composed of cement, slaked lime, vitrified microspheres and powder moisturizer, and the powder moisturizer is polyacrylamide, The recycled powder composite filler is composed of main material and additive. The main material is composed of recycled powder, fine aggregate and cement, and the weight ratio of recycled powder, fine aggregate and cement is (55 - 65):(20 - 40):(10 - 15); the additive is water reducing agent and expansive agent.

2. The re-mixed recycled cement stabilized macadam base course material according to claim 1, Characterized in that: The mass ratio relationship between the recycled powder composite filler and the skeleton aggregate is determined according to the following method: (1) Calculate the mass ratio A of the recycled powder composite filler to the skeleton aggregate according to formula (I) 1 ， Where: ρ 骨捣 is the compacted density of the skeletal aggregate; ρ 骨理 is the theoretical density of the skeletal aggregate; ρ 粉湿 is the wet density corresponding to the maximum dry density obtained by the recycled powder composite filler under the heavy compaction condition; (2)Recheck the mass ratio of the recycled powder composite filler to the skeleton aggregate in the test to obtain the mass ratio A 2 ; The recycled powder composite filler and the skeleton aggregate are respectively subjected to the heavy compaction test according to A 1 ×80%, A 1 ×90%, A 1 ×100%, A 1 ×110%, A 1 ×120% to determine the optimal mass ratio A through the maximum dry density 2 ; (3)Calculate the mass ratio A of the recycled powder composite filler to the skeleton aggregate according to formula (II). 3 : 。 3. The re-mixed recycled cement stabilized macadam base course material according to claim 1 or 2, Characterized in that, The grading range of the skeleton aggregate is: The passing rate of the standard sieve hole of 37.5mm is 100%; The passing rate range of the standard sieve hole of 31.5mm is 80 - 100%; The passing rate range of the standard sieve hole of 26.5mm is 30 - 60%; The passing rate range of the standard sieve hole of 19mm is 0 - 10%.

4. The re-mixed recycled cement stabilized macadam base course material according to claim 3, Characterized in that: The skeleton aggregate is composed of recycled aggregate and new aggregate.

5. The re-mixed recycled cement stabilized macadam base course material according to claim 1 or 2, Characterized in that, The mass ratio of the recycled aggregate interface treatment agent to the skeleton aggregate is (1 - 3):100, The weight ratio of each raw material of the recycled aggregate interface treatment agent is respectively: Cement 50 - 60 parts Slaked lime 20 - 40 parts Vitrified microspheres 5 - 10 parts Powder moisturizer 0.5 - 1 part.

6. The re-mixed recycled cement stabilized macadam base course material according to claim 1 or 2, Characterized in that: The water reducing agent is naphthalene series water reducing agent or polycarboxylate water reducing agent, and the dosage accounts for 0.2 - 1.0% of the mass of the main material of the recycled powder composite filler; The expansive agent is UEA series expansive agent, and the dosage accounts for 1% - 2% of the mass of the main material of the recycled powder composite filler.

7. The re-mixed recycled cement stabilized macadam base course material according to claim 1 or 2, Characterized in that: The fine aggregate is manufactured sand or river sand with a particle size of 3mm - 6mm, and its grading meets the following requirements: The passing rate of the standard sieve hole of 9.5mm is 100%; The passing rate range of the standard sieve hole of 4.75mm is 90 - 100%; The passing rate range of the standard sieve hole of 2.36mm is 0 - 10%; The passing rate range of the standard sieve hole of 0.075mm is 0 - 2%.

8. Re-mixed recycled cement stabilized macadam base course, Characterized in that, It is paved with the base course material according to claim 1, and includes the following processes: S1. Mix the skeleton aggregate, interface treatment agent and appropriate amount of water evenly according to a certain ratio, and obtain a skeleton structure through paving, leveling, compaction and curing; S2. Mix the recycled powder composite filler and appropriate amount of water evenly according to the ratio, and pave it on the surface of the skeleton structure after curing; S3. Mix the recycled powder composite filler and the skeleton aggregate on-site, and complete the paving of the crushed stone base after compaction.

9. The re-mixed recycled cement stabilized crushed stone base according to claim 8, characterized in that: In step S1, after the skeleton aggregate, the interface treatment agent, and water are mixed evenly, level it to a suitable height, then vibrate and compact it 2-3 times with a single-drum roller, and use a double-drum roller to eliminate excessive compaction marks on the surface. The compacted skeleton structure is maintained moist for 2-3 days, and the unconfined compressive strength of the specimens cured indoors for 7 days is not less than 1.5 MPa. The added amount of water is 1% - 3% of the mass of the skeleton aggregate.

10. The re-mixed recycled cement stabilized crushed stone base according to claim 8, characterized in that: In step S2, the mixing water consumption is determined by increasing the optimal water consumption determined by the indoor heavy compaction test by 1%.

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