CN109085073B - New and old asphalt mixing degree characterization method based on dynamic modulus of mixture - Google Patents
New and old asphalt mixing degree characterization method based on dynamic modulus of mixture Download PDFInfo
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Abstract
The invention relates to a new and old asphalt mixing solubility degree characterization method based on the dynamic modulus of a mixture, which is used for testing various performance indexes of an RAP material, matrix asphalt, aggregate and mineral powder; preparing a hot-mix recycled asphalt mixture according to the existing recycling standard, and preparing a test piece; testing the dynamic modulus of each test piece, and drawing a dynamic modulus main curve obtained by actual measurement; adding different amounts of old asphalt and regenerant into the matrix asphalt to prepare asphalt mucilage of different mixing degrees of new and old asphalt; respectively carrying out DSR tests on different asphalt mucilages to measure the composite modulus and the phase angle of each asphalt mucilage; predicting the dynamic modulus of the mixture in different asphalt cement states, and drawing a dynamic modulus prediction main curve; and (5) representing the miscibility degree of the new asphalt and the old asphalt in each reclaimed mixture. The invention selects the method of indirect performance test with the maximum controllability for research, eliminates the influence of mixing factors, personal errors and mineral aggregate gradation as much as possible and improves the test precision of the test.
Description
Technical Field
The invention belongs to the technical field of preparation of road building materials, and relates to a method for representing the mixing and dissolving degree of new and old asphalt based on the dynamic modulus of a mixture.
Background
The existing methods for characterizing the miscibility degree of the new asphalt and the old asphalt are roughly divided into a macroscopic test method and a microscopic test method, wherein the macroscopic test method comprises a step-by-step extraction method and an indirect performance test method, and the microscopic test method comprises a binder marking method and a differential identification method. The two methods have advantages and disadvantages, and the microscopic testing method has expensive testing equipment and complex operation and is mainly suitable for the research of the microscopic mixing and dissolving mechanism; the macroscopic test method has slightly low precision, but the operation comparison method is simple, and the influence of the mixing degree change on the performance of the mixture can be reflected macroscopically.
Karlsson and Isacsson mark the regenerant by using 8 substances such as polystyrene which are sensitive to infrared light, and then observe the mixing and dissolving process between old asphalt, new asphalt and the regenerant by a Fourier infrared spectrometer, thereby preliminarily showing the influence of the temperature and the composition structure of the regenerant on the mixing and dissolving process.
Selecting RAP material with mesh size below 4.75mm and new aggregate with particle size of 9.5mm, adding new asphalt with the same amount as that of the old asphalt, mixing to form mixture, and detecting the content of mineral powder in asphalt mucilage attached to the new aggregate so as to calculate the mixing degree between the new asphalt and the old asphalt through the powder-to-glue ratio in the regenerated mixture.
Huang carries out four-step extraction test on the recycled mixture, and then analyzes the mixing degree of the new and old asphalts by comparing the viscosity and the composite modulus of each layer of asphalt and combining the difference of the performances of different layers of asphalt, and the test result shows that the new and old asphalts are in an incomplete mixing state.
Tests on mixtures with different RAP contents by McDaniel and Shah with Bonaquist show that the compatibility of the old and new asphalt is nearly 100% when the RAP content is less than 15%, and that the compatibility of the old and new asphalt is not 100% when the RAP content is more than 40%.
In the research of the test method for the miscibility degree of the new asphalt and the old asphalt, a plurality of scholars make a plurality of effective researches. However, the methods have advantages and disadvantages, and cannot accurately test the true mixing degree of the new asphalt and the old asphalt.
The invention patent with the patent application number of CN201610503004.0 discloses a test method for measuring the fusion degree of new and old asphalt of a hot recycled asphalt mixture, which comprises the following steps: (1) designing and drafting production conditions according to the mixing proportion to prepare test materials; (2) mixing, separating, recovering and measuring the test material prepared in the step (1) according to a set production condition; (3) and (3) finishing the test results measured in the step (2) and calculating the fusion degree of the new asphalt and the old asphalt. The fusion degree is based on the proportion of the old asphalt in the hot recycled asphalt mixture in the total asphalt, and the larger the value is, the better the fusion degree of the new asphalt and the old asphalt is. However, the patent can not test the true miscibility degree of the new asphalt and the old asphalt, on one hand, the control of the raw material gradation and the asphalt content is not well carried out, and on the other hand, the error of the test result is larger.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a method for representing the mixing degree of new asphalt and old asphalt based on the dynamic modulus of a mixture, a method for indirectly testing the performance with the maximum controllability is selected for research, the influence of mixing factors, human errors and mineral aggregate gradation is eliminated as much as possible, and the test precision is improved.
The invention provides the following technical scheme:
a new and old asphalt miscibility degree characterization method based on mixture dynamic modulus comprises the following steps:
the method comprises the following steps: testing various performance indexes of RAP materials, matrix asphalt, aggregates and mineral powder;
step two: preparing a hot-mix recycled asphalt mixture according to the existing recycling standard, and preparing a test piece;
step three: testing the dynamic modulus of each test piece, and drawing a dynamic modulus main curve obtained by actual measurement;
step four: adding different amounts of old asphalt and regenerant into the matrix asphalt to prepare asphalt mucilage of different mixing degrees of new and old asphalt;
step five: respectively carrying out DSR tests on different asphalt mucilages to measure the composite modulus and the phase angle of each asphalt mucilage;
step six: predicting the dynamic modulus of the mixture with different mixing degrees in the asphalt cement state, and drawing a dynamic modulus prediction main curve;
step seven: quantitatively representing the mixing and dissolving degree of the new asphalt and the old asphalt in each reclaimed mixture.
Preferably, when the hot-mix recycled asphalt mixture is prepared in the second step, the RAP mixing amount is 40-60%, the mixing temperature is 150-170 ℃, the mixing time is not more than 3mins, and the RAP material preheating temperature is 100-120 ℃.
Preferably, in any of the above schemes, when the hot-mix recycled asphalt mixture is prepared in the second step, the mixing amount of the RAP is 40%, the mixing temperature is 150 ℃, the mixing time is 2mins, and the preheating temperature of the RAP material is 100 ℃.
Preferably, in any of the above schemes, when the hot-mix recycled asphalt mixture is prepared in the second step, the mixing amount of the RAP is 50%, the mixing temperature is 165 ℃, the mixing time is 3mins, and the preheating temperature of the RAP material is 110 ℃.
Preferably, in any of the above schemes, when the hot-mix recycled asphalt mixture is prepared in the second step, the mixing amount of the RAP is 60%, the mixing temperature is 170 ℃, the mixing time is 3mins, and the preheating temperature of the RAP material is 120 ℃.
In any of the above embodiments, preferably, in the second step, the test piece is a cylindrical test piece.
In any of the above embodiments, preferably, in the second step, the test piece is a cylindrical test piece having a height of 100mm and a diameter of 100 mm.
In any of the above embodiments, preferably, in step three, the uniaxial compression test is used to test the dynamic modulus of the test piece.
In any of the above embodiments, it is preferable that the uniaxial compression test is carried out at test temperatures of 20 ℃, 35 ℃ and 50 ℃ and loading frequencies of 0.1Hz, 0.5Hz, 1Hz, 5Hz, 10Hz and 25 Hz.
In any of the above schemes, preferably, in the fourth step, old asphalt and regenerant with different mixing amounts are added into the base asphalt to prepare asphalt mucilage with four mixing degrees of 100%, 90%, 80% and 70% of new and old asphalt.
Preferably, in any of the above schemes, in the fourth step, new and old mixed asphalts with old asphalt contents of 100%, 90%, 80% and 70% are prepared, and a proper amount of mineral powder is added according to the powder-to-rubber ratio in the actual regenerated mixture, and four asphalt mucilages with different mixing degrees of the new and old asphalts are obtained after fully and uniformly mixing.
In any of the above embodiments, preferably, the preparation method of the asphalt cement when the new asphalt and the old asphalt are 100% miscible is as follows: according to the total asphalt consumption of 4.4 percent in the reclaimed mixture, the proportion of the old asphalt to the new asphalt (reclaiming agent) is 1.3 percent: 3.1 percent, then adding mineral powder according to the powder-to-rubber ratio of 1:1.3 in the regenerated mixture, and fully and uniformly mixing to obtain the asphalt mucilage when the new asphalt and the old asphalt are mixed and dissolved at 100 percent.
In any of the above embodiments, preferably, the preparation method of the asphalt cement with the new and old asphalt mixing degree of 90% is as follows: according to the proportion of the old asphalt and the new asphalt (regenerant), the proportion of the old asphalt and the new asphalt (regenerant) is 1.17%: 3.1 percent, and adding mineral powder according to the powder-to-rubber ratio of 1:1.3 to obtain asphalt mucilage with the mixing degree of 90 percent of the new asphalt and the old asphalt. That is, 90% of the total old asphalt content (i.e., 1.3%: 1.17% of the added amount of old asphalt) was extracted and mixed with the same fresh asphalt (rejuvenating agent) according to the ratio (1.3%: 3.1%) of the old asphalt to the fresh asphalt (rejuvenating agent).
In any of the above embodiments, preferably, the preparation method of the asphalt cement with 80% miscibility degree of the old asphalt and the new asphalt is as follows: the ratio of old asphalt to new asphalt (regenerant) is 1.04%: 3.1 percent of the old asphalt with the powder-to-rubber ratio of 1:1.3 and 20 percent of the mixed asphalt is replaced by mineral powder with equal mass to obtain asphalt mucilage of the new asphalt and the old asphalt with the mixing degree of 80 percent.
According to the ratio of old asphalt to new asphalt (regenerant) (1.3%: 3.1%), 80% of the total old asphalt content (i.e. the added amount of old asphalt is 1.3% × 80% ═ 1.04%) was extracted and mixed with the same new asphalt (regenerant) to obtain a ratio of old asphalt to new asphalt (regenerant) of 1.04%: 3.1 percent, and adding mineral powder according to the powder-to-rubber ratio of 1:1.3 to obtain asphalt mucilage with the mixing degree of 80 percent of the new asphalt and the old asphalt.
In any of the above embodiments, preferably, the preparation method of the asphalt cement with 70% miscibility degree of the old asphalt and the new asphalt is as follows: the ratio of old asphalt to new asphalt (regenerant) was 0.91%: 3.1 percent, the powder-to-rubber ratio is 1:1.3, and 30 percent of old asphalt which does not participate in mixing is replaced by mineral powder with equal mass to obtain asphalt mucilage of new and old asphalt at the mixing degree of 70 percent.
According to the ratio (1.3%: 3.1%) of the old asphalt to the new asphalt (regenerant), 70% of the total old asphalt content (i.e. the added amount of the old asphalt is 1.3% × 70% ═ 0.91%) was extracted and mixed with the same new asphalt (regenerant) to obtain a ratio of the old asphalt to the new asphalt (regenerant) of 0.91%: 3.1 percent, and adding mineral powder according to the powder-to-rubber ratio of 1:1.3 to obtain asphalt mucilage with 70 percent of mixing degree of new asphalt and old asphalt.
In any of the above embodiments, in the fifth step, the test temperature in the DSR test is 20 ℃, 35 ℃ and 50 ℃, and the scanning frequency is 0.1Hz to 25 Hz.
Preferably, in any of the above schemes, in the fifth step, the measured coincidence modulus and phase angle of each asphalt cement are substituted into the improved Hirsch model, and a main prediction curve of the dynamic modulus of the mixture containing each asphalt cement is obtained as shown in the following formula.
In the formula:
in the formula: e1、E2、EaThe elastic modulus and the aggregate modulus of the springs 1 and 2 in the Burgers model are respectively; eta1、η2The viscosity of the sticky pot 1 and the viscosity of the sticky pot 2 are respectively set; omega is angular frequency; delta is a phase angle; upsilon is Poisson's ratio; VMA is mineral aggregate void fraction; VFA is the asphalt saturation;
and
the dynamic modulus and the dynamic shear modulus of the asphalt cement are respectively.
Preferably, in the sixth step, an improved Hirsch model is introduced, and relevant parameters such as the composite shear modulus and the phase angle of each asphalt cement are brought into the Hirsch model to predict the dynamic modulus of the mixture.
Preferably, in step seven, the predicted dynamic modulus master curve is used as a reference line, and compared with the actually measured dynamic modulus master curve, and the miscibility degree of the new asphalt and the old asphalt in each reclaimed mixture is quantitatively represented.
Has the advantages that: the invention provides a method for characterizing the mixing and dissolving degree of new and old asphalt based on the dynamic modulus of a mixture, firstly, from the aspect of raw material control, the method carries out variability analysis and treatment on an RAP material, and further reduces the variability of mineral aggregate synthetic gradation; then, the content of the old asphalt is controlled to be a single variable, so that the change of the modulus of the mixture is only influenced by the change of the content of the asphalt, the influence of mixing factors, human errors and mineral aggregate gradation is eliminated as much as possible, and the test precision is improved; secondly, selecting a semi-empirical semi-theoretical model to estimate the dynamic modulus of the mixture, which is more accurate than the prior full-empirical or full-theoretical model; and finally, comparing the actually measured dynamic modulus main curve with the estimated mixture main curve, and accurately representing the mixing and dissolving degree of the new asphalt and the old asphalt in the mixture by utilizing the comparison between the main curves. The invention eliminates the influence of mixing factors, personal errors and mineral aggregate gradation as much as possible and improves the test precision.
Drawings
FIG. 1 is a graph of the compositional grading of a blend;
FIG. 2 is a main curve of the actually measured dynamic modulus of a 50% RAP blending quantity regeneration mixture;
FIG. 3 is a main curve of the predicted dynamic modulus of each recycled blend;
FIG. 4 is a master curve representation of the predicted dynamic modulus of the reclaimed blend.
Detailed Description
In order to further understand the technical features of the present invention, the present invention is described in detail with reference to the specific embodiments below. The embodiments are given by way of illustration only and not by way of limitation, and any insubstantial modifications, based on the present disclosure, may be made by those skilled in the art without departing from the scope of the present disclosure.
The present invention will be further described with reference to the following specific examples, but the present invention is not limited to the following examples.
Take 50% RAP mixed regenerated asphalt mixture as an example.
(1) The performance indexes of the recycled mixture with the AC-16 type RAP mixing amount of 50 percent, the old asphalt, the matrix asphalt (AH-70 road petroleum asphalt), the A type regenerant, the aggregate and the mineral powder are respectively shown in tables 1.1-1.6.
TABLE 1.1 Performance test results for old asphalts
TABLE 1.2 AH-70 Pitch Main technical Performance test results
TABLE 1.3 regenerant Performance indices
TABLE 1.4 Fine aggregate Performance test results
TABLE 1.5 coarse aggregate Performance test results
TABLE 1.6 mineral powder Performance test results
The technical indexes of the AH-70 road petroleum asphalt meet the technical regulation about No. 70 asphalt in the technical Specification for road asphalt pavement construction (JTG F40-2004). The performance indexes of the coarse aggregate, the fine aggregate and the mineral powder all meet the relevant regulations in the Highway engineering aggregate test regulation (JTG E42-2005).
(2) And determining the optimal asphalt dosage of the reclaimed asphalt mixture according to the current regeneration specification and a Marshall mix proportion design method. The synthesis grading is shown in FIG. 1.
Primarily selecting the content of asphalt according to actual engineering experience, taking the primarily selected asphalt as a median and the primarily selected asphalt as 4.3%, taking 5 asphalt dosages according to a variation gradient of 0.5%, wherein the asphalt dosages are respectively 3.3%, 3.8%, 4.3%, 4.8% and 5.3%, then manufacturing a Marshall test piece (the Marshall test piece is a cylindrical test piece with the height of 100mm and the diameter of 100 mm) to test each volume index, and finally measuring that the optimal asphalt dosage of the regenerated asphalt mixture under the condition of 50% of RAP dosage is 4.4%.
(3) Firstly, the dynamic modulus of the regeneration mixture is measured actually, and then a dynamic modulus main curve is drawn according to the dynamic moduli. The invention adopts a uniaxial compression test according to the specification, adopts three test temperatures of 20 ℃, 35 ℃ and 50 ℃ and six loading frequencies of 0.1Hz, 0.5Hz, 1Hz, 5Hz, 10Hz and 25Hz, respectively draws a dynamic modulus main curve of the regeneration mixture under 50 percent of RAP doping according to the test result, draws a double logarithmic coordinate as shown in figure 2 with the reference temperature of 35 ℃.
(4) Preparing the asphalt mucilage with the old asphalt contents of 100%, 90%, 80% and 70% respectively. The preparation process of the asphalt mucilage comprises the following steps: preparing asphalt mucilage with the mixing degree of 100 percent of new asphalt and old asphalt: firstly, according to the total asphalt consumption of 4.4% in the regeneration mixture, wherein the proportion of the old asphalt to the new asphalt (regenerant) is 1.3%: 3.1 percent, finally adding mineral powder according to the powder-to-rubber ratio of 1:1.3 in the regenerated mixture, and fully and uniformly mixing to obtain asphalt mucilage when the new asphalt and the old asphalt are mixed and dissolved at 100 percent; ② preparing the asphalt mucilage with 90 percent mixing degree of new and old asphalt: according to the proportion of old asphalt and new asphalt (regenerant), 90% of old asphalt is selected to be mixed with the same new asphalt and regenerant, namely the proportion of the old asphalt to the new asphalt (regenerant) is 1.17%: 3.1 percent, and adding mineral powder according to the powder-to-rubber ratio of 1:1.3 to finally obtain asphalt mucilage of the new asphalt and the old asphalt at the mixing degree of 90 percent; preparing asphalt mucilage with 80% mixing degree of new and old asphalt: similarly, the ratio of the old asphalt to the new asphalt (regenerant) is 1.04%: 3.1 percent and the powder-to-rubber ratio is 1:1.3, and asphalt cement with the mixing degree of 80 percent of new and old asphalt is obtained; preparing asphalt mucilage with 70% miscibility degree of new and old asphalt: the ratio of old asphalt to new asphalt (regenerant) was 0.91%: 3.1 percent and the powder-to-rubber ratio is 1:1.3, and the asphalt cement with the mixing degree of 70 percent of the new asphalt and the old asphalt is obtained.
(5) DSR (HR-1 type) tests are respectively carried out on the four kinds of asphalt mucilage, dynamic frequency scanning is adopted in the tests, the test temperature is 20 ℃, 35 ℃ and 50 ℃, and the scanning frequency is 0.1Hz-25 Hz. And substituting the measured conforming modulus and phase angle of each asphalt cement into the improved Hirsch model, wherein the formula is shown as 1-1, and obtaining a main prediction curve of the dynamic modulus of the mixture containing each asphalt cement, which is shown as a figure 3.
In the formula:
in the formula: e1、E2、EaThe elastic modulus and the aggregate modulus of the springs 1 and 2 in the Burgers model are respectively; eta1、η2The viscosity of the sticky pot 1 and the viscosity of the sticky pot 2 are respectively set; omega is angular frequency; delta is a phase angle; upsilon is Poisson's ratio; VMA is mineral aggregate void fraction; VFA is the asphalt saturation;
and
the dynamic modulus and the dynamic shear modulus of the asphalt cement are respectively.
(6) And (3) taking the predicted dynamic modulus main curve as a reference line, comparing the predicted dynamic modulus main curve with the actually measured dynamic modulus main curve, and quantitatively representing the mixing and dissolving degree of the new asphalt and the old asphalt in each regeneration mixture. The characterization is shown in fig. 4.
In fig. 4, the main curve represented by the diamond block is the main curve of the dynamic modulus obtained through actual measurement, and the other four main curves (represented by the circular block, the triangular block and the rectangular block) predicted to obtain the main curve of which the dynamic modulus is gray are provided. According to the interpolation relation, the four gray main curves represent 70%, 80%, 90% and 100% from top to bottom, the endpoint A is 71%, the endpoint B is 78%, so that the endpoint A is 71% and the endpoint B is 78%, and the mixing mode of the recycled mixture with 50% RAP mixing amount obtained by averaging is that the mixing degree of the new and old asphalt in the recycled mixture is 74.5% at 165 ℃.
Similarly, taking the reclaimed mixture with 30 percent and 40 percent of RAP as an example, the mixing degrees of the new asphalt and the old asphalt in the mixture are respectively 92.5 percent and 86.0 percent according to the method in the mixing mode at 165 ℃.
Firstly, from the aspect of raw material control, the method performs variability analysis and treatment on the RAP material, and further reduces the variability of mineral aggregate synthesis gradation; then, the content of the old asphalt is controlled to be a single variable, so that the change of the modulus of the mixture is only influenced by the change of the content of the asphalt, the influence of mixing factors, human errors and mineral aggregate gradation is eliminated as much as possible, and the test precision is improved; secondly, selecting a semi-empirical semi-theoretical model to estimate the dynamic modulus of the mixture, which is more accurate than the prior full-empirical or full-theoretical model; and finally, comparing the actually measured dynamic modulus main curve with the estimated mixture main curve, and accurately representing the mixing and dissolving degree of the new asphalt and the old asphalt in the mixture by utilizing the comparison between the main curves. The invention eliminates the influence of mixing factors, personal errors and mineral aggregate gradation as much as possible and improves the test precision.
It should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (7)
1. A new and old asphalt mixing degree characterization method based on mixture dynamic modulus is characterized in that: the method comprises the following steps:
the method comprises the following steps: testing various performance indexes of RAP materials, matrix asphalt, aggregates and mineral powder;
step two: preparing a hot-mix recycled asphalt mixture according to the existing recycling specification, and preparing a test piece, wherein when the hot-mix recycled asphalt mixture is prepared, the RAP mixing amount is 40-60%, the mixing temperature is 150-170 ℃, the mixing time is not more than 3mins, and the RAP material preheating temperature is 100-120 ℃;
step three: testing the dynamic modulus of each test piece, and drawing a dynamic modulus main curve obtained by actual measurement;
step four: adding different amounts of old asphalt and regenerant into the base asphalt to prepare new and old asphalt
Asphalt mucilages with different miscibility degrees;
step five: DSR test is respectively carried out on different asphalt mucilage to measure the composite modulus of each asphalt mucilage
And a phase angle;
step six: predicting the dynamic modulus of the mixture with different mixing degrees in the state of the asphalt cements, drawing a dynamic modulus prediction main curve, introducing an improved Hirsch model, and substituting the composite shear modulus and phase angle related parameters of each asphalt cement into the Hirsch model to predict the dynamic modulus of the mixture, wherein the formula is as follows;
in the formula:
in the formula:E 1、E 2、E athe elastic modulus and the aggregate modulus of the springs 1 and 2 in the Burgers model are respectively; eta1、η2The viscosity of the sticky pot 1 and the viscosity of the sticky pot 2 are respectively set; omega is angular frequency; delta is a phase angle; upsilon is Poisson's ratio;VMAthe mineral aggregate void fraction;VFAis the asphalt saturation;
and
the dynamic modulus and the dynamic shear modulus of the asphalt cement are respectively;
step seven: quantitatively representing the mixing and dissolving degree of the new and old asphalt in each regeneration mixture, comparing the predicted dynamic modulus main curve with the actually measured dynamic modulus main curve by taking the predicted dynamic modulus main curve as a reference line, and quantitatively representing the mixing and dissolving degree of the new and old asphalt in each regeneration mixture.
2. The method for characterizing the miscibility degree of the old asphalt and the new asphalt based on the dynamic modulus of the mixture as claimed in claim 1, wherein: in the second step, the test piece is a cylindrical test piece.
3. The method for characterizing the miscibility degree of the old asphalt and the new asphalt based on the dynamic modulus of the mixture as claimed in claim 1, wherein: in the third step, the dynamic modulus of the test piece is tested by using a uniaxial compression test.
4. The method for characterizing the miscibility degree of the old asphalt and the new asphalt based on the dynamic modulus of the mixture as claimed in claim 3, wherein: in the uniaxial compression test, the test temperatures were 20 ℃, 35 ℃ and 50 ℃ and the loading frequencies were 0.1Hz, 0.5Hz, 1Hz, 5Hz, 10Hz, and 25 Hz.
5. The method for characterizing the miscibility degree of the old asphalt and the new asphalt based on the dynamic modulus of the mixture as claimed in claim 1, wherein: in the fourth step, old asphalt and regenerant with different mixing amounts are added into the base asphalt to prepare asphalt mucilage with four mixing degrees of 100%, 90%, 80% and 70% of new and old asphalt.
6. The method for characterizing the miscibility degree of the old asphalt and the new asphalt based on the dynamic modulus of the mixture as claimed in claim 1, wherein: and in the fourth step, new and old mixed asphalts with the old asphalt contents of 100%, 90%, 80% and 70% are prepared respectively, a proper amount of mineral powder is added according to the powder-to-rubber ratio in the actual regenerated mixture, and four kinds of asphalt mucilage with different mixing degrees of the new and old asphalts are obtained after the four kinds of asphalt mucilage are fully and uniformly mixed.
7. The method for characterizing the miscibility degree of the old asphalt and the new asphalt based on the dynamic modulus of the mixture as claimed in claim 1, wherein: in the fifth step, the test temperature in the DSR test is 20 ℃, 35 ℃ and 50 ℃, and the scanning frequency is 0.1Hz-25 Hz.
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| CN110196318B (en) * | 2019-06-03 | 2021-11-26 | 交通运输部公路科学研究所 | Method for detecting fusion degree of cement emulsified asphalt and old asphalt |
| CN110196319A (en) * | 2019-06-19 | 2019-09-03 | 重庆交通大学 | Asphalt material dynamic shear modulus low-temperature test method |
| CN111785338B (en) * | 2020-07-16 | 2023-06-27 | 山东交通学院 | Grading method, grading system, grading medium and grading equipment suitable for recycled asphalt mixture |
| CN111812308B (en) * | 2020-07-21 | 2022-06-17 | 山东交通学院 | Method for quantifying new-old asphalt interface fusion degree based on asphalt binder performance |
| CN111739592B (en) * | 2020-07-21 | 2023-08-04 | 山东交通学院 | Method for quantifying new-old asphalt interface fusion degree based on asphalt mixture performance |
| CN113702427B (en) * | 2021-06-03 | 2023-06-13 | 东南大学 | Evaluation method for miscibility characteristics of new asphalt and old asphalt and regenerant in-situ thermal regeneration |
| CN114002093B (en) * | 2021-12-27 | 2022-04-05 | 山东省交通科学研究院 | Method for determining resilience modulus of pavement aggregate layer material in real time |
| CN114459918B (en) * | 2022-01-19 | 2023-08-29 | 同济大学 | Method for predicting high-low temperature performance grade of regenerated asphalt with different proportions of new asphalt and old asphalt |
| CN116579223B (en) * | 2023-07-14 | 2023-09-29 | 中南大学 | Dynamic modulus prediction method for reclaimed asphalt mixture |
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