Method for determining optimal regeneration scheme of aged high-viscosity asphalt

Abstract

The invention discloses a method for determining an optimal regeneration scheme of aged high-viscosity asphalt, which comprises the following steps: selecting different types and mixing amounts of regenerant to prepare various regenerated high-viscosity asphalt; obtaining a regeneration performance index set; carrying out dimension reduction on the regeneration performance index set based on principal component analysis; and clustering the principal component score points based on system clustering analysis, and determining the regenerated high-viscosity asphalt belonging to the same cluster as the original high-viscosity asphalt, namely an optimal regeneration scheme. By adopting the technical scheme provided by the invention, the optimal type and mixing amount of the regenerant can be conveniently determined while the comprehensive recovery effect of the performance of the aged asphalt is considered.

Description

Technical Field

[0001] The present invention belongs to the technical field of road engineering materials, and in particular relates to a method for determining an optimal regeneration scheme for aged high-viscosity asphalt. Background Art

[0002] At present, with the continuous increase of traffic load and the continuous deterioration of climate environment, the aging phenomenon of asphalt binder in asphalt pavement is becoming more and more serious, which seriously affects the service level and service life of asphalt pavement. The maintenance and reconstruction of asphalt pavement will produce a large amount of recycled asphalt mixture. With the increasing depletion of fossil energy, the reuse of recycled asphalt mixture has received widespread attention in the road industry. The use of recycled asphalt mixture can save a lot of asphalt materials, reduce greenhouse gas emissions, and promote economic and environmental sustainable development. However, the widespread application of high-proportion recycled asphalt mixture still faces many challenges. Direct use of these highly hardened aged asphalts seriously affects the stability of asphalt pavement. In this case, adding regeneration agent is an effective means to increase the amount of recycled asphalt mixture and ensure the performance of recycled asphalt pavement.

[0003] High-viscosity asphalt is a polymer-modified asphalt with a high polymer content (6wt%-8wt%), which is widely used in large-void permeable asphalt pavements. Due to the well-developed void structure and strong environmental exposure of permeable asphalt pavements, high-viscosity asphalt will suffer extremely severe aging during service, leading to oxidation of the asphalt phase and degradation of the polymer phase. Oxidation of the asphalt phase causes the aromatic components in the asphalt to undergo oxidation and aromatization reactions, gradually transforming into colloids and asphaltene. Polymer degradation will lead to polymer degradation and destruction of the phase structure. Due to the rich polymer phase structure and complex aging process of high-viscosity asphalt, how to regenerate aged high-viscosity asphalt has become one of the main problems that plague road researchers at home and abroad.

[0004] Light component-based regeneration agents generally contain a high aromatic content, which can replenish the light components lost during asphalt aging, dissolve asphaltene components, and restore the colloidal structure of aged asphalt. In recent years, researchers have developed a variety of light component-based regeneration agents to reactivate the performance of aged asphalt by replenishing aromatic components and diluting polar products generated during aging. Different types of light component-based regeneration agents are mainly derived from petroleum-based products (such as engine oil, aromatic oil, rubber oil, etc.) and biological resources (such as vegetable oil, waste cooking oil, etc.). Light component-based regeneration agents have been proven to effectively improve the low-temperature cracking performance and fatigue resistance of aged asphalt. However, although light component-based regeneration agents can better restore the performance of aged asphalt, there are still many problems in their widespread application. The thermal stability and anti-aging performance of light component-based regeneration agents are still the key issues that need to be addressed.

[0005] For aged polymer modified asphalt, light component-based regeneration agents can only adjust the components of asphalt, but cannot reverse the degradation of polymers and phase structure decay, and the viscoelastic properties and ductility of aged polymer modified asphalt cannot be restored. For this reason, some researchers have proposed using a polymer-based regeneration agent compounded with multiple components to regenerate aged polymer modified asphalt. Patent CN116875067A discloses a vegetable oil-based SBS modified asphalt regeneration agent, which is mainly composed of 1 part by weight of vegetable oil, 0.29-0.6 parts by weight of cyclohexane oil, 0.04-0.05 parts by weight of phenolic antioxidants, 0.02-0.03 parts by weight of benzotriazole ultraviolet absorbers, 0.001-0.003 parts by weight of glutamine transaminase, 0.02-0.1 parts by weight of polyisocyanates, and 0.05-0.2 parts by weight of SBS modifiers. The composite regeneration agent can restore the performance of aged SBS modified asphalt to the pre-aging state. Patent CN113265153A discloses an asphalt composite regeneration agent composed of 4-6 parts of styrene-isoprene-styrene block copolymer, 2-5 parts of antioxidant, 100 parts of plasticizer, 3-6 parts of anti-stripping agent and 6-12 parts of powdered rubber, which can improve the low temperature resistance of recycled asphalt mixture.

[0006] Although a lot of research has been done on the regeneration of aged asphalt and aged polymer-modified asphalt, these research results are not completely applicable to the regeneration of aged high-viscosity asphalt with high polymer content. In addition, current research also has certain limitations in the optimization of regeneration agents. The traditional method for determining the type and dosage of regeneration agents is based on needle penetration, softening point, viscosity and low-temperature ductility tests. Although this method is simple to operate, it is not suitable for polymer-modified asphalt. Patent CN111241713A discloses a method for determining the amount of regeneration agent based on the critical temperature corresponding to the critical values ​​of asphalt rutting factor and fatigue factor. Purdy and other scholars suggested using multiple stress creep tests to optimize the type and dosage of regeneration agents in regenerated asphalt. Lin and other scholars proposed using low, medium and high temperature rheological tests to evaluate the regeneration effects of different regeneration agents on aged SBS modified asphalt, and then determine the best regeneration agent type and reasonable dosage range. Patent CN109486221A discloses a method for determining the amount of regeneration agent for waste SBS modified asphalt based on the phase structure parameters (SBS particle area ratio) of SBS modified asphalt. Although researchers have conducted extensive research on the optimal selection of regeneration agents in regenerated asphalt, the optimal types and dosages of regeneration agents determined by different evaluation methods and research methods are sometimes inconsistent, resulting in confusion in the research conclusions. In the current optimization methods for regeneration agents, it is difficult to simultaneously consider the comprehensive recovery effects of the macro and micro properties of aged asphalt. There is still a lack of a scientific regeneration evaluation system that can more conveniently determine the optimal type and dosage of regeneration agents while taking into account the comprehensive recovery effects of aged asphalt properties. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a method for determining the best regeneration scheme for aged high-viscosity asphalt, based on experiments, comprehensive macro and micro performance tests are conducted on a variety of regenerated high-viscosity asphalts to obtain a set of performance evaluation indicators for regenerated high-viscosity asphalt; based on principal component analysis, the regeneration performance indicator set is reduced in dimension to convert it into two-dimensional or three-dimensional principal component score points; based on system clustering analysis, the principal component score points are clustered to find the regenerated high-viscosity asphalt that belongs to the same cluster as the original high-viscosity asphalt, which is the best regeneration scheme.

[0008] To achieve the above object, the present invention adopts the following technical solution:

[0009] A method for determining an optimal regeneration scheme for aged high-viscosity asphalt, comprising:

[0010] Select different types and dosages of regeneration agents to prepare a variety of regenerated high-viscosity asphalts;

[0011] Get the regeneration performance index set;

[0012] Based on principal component analysis, the dimension of the regeneration performance index set is reduced, and the performance evaluation index set is converted into limited principal components;

[0013] Based on the system cluster analysis, the principal component score points are clustered to determine the recycled high-viscosity asphalt that belongs to the same cluster as the original high-viscosity asphalt, which is the best regeneration solution.

[0014] Preferably, the types of regeneration agents include light component-based regeneration agents and polymer-based regeneration agents, and the dosage of the regeneration agents is 4%, 8% and 12% of the mass of the aged high-viscosity asphalt.

[0015] Preferably, the regeneration performance evaluation indexes include: phase angle main curve platform, phase angle platform area frequency value, platform area phase angle difference, viscoelastic transition temperature, strain recovery rate, irreversible creep compliance, GR parameter, fracture ductility, low temperature toughness index, polymer peak elution time, and polymer peak corresponding molecular weight.

[0016] Preferably, the system cluster analysis combines and classifies different recycled high-viscosity asphalts by comparing the distances between the principal component score points of different recycled high-viscosity asphalts, and the number of clusters is determined comprehensively based on the number of high-viscosity asphalt regeneration schemes and the distribution of principal component score points.

[0017] Preferably, the optimal regeneration scheme should include the type and dosage of the regeneration agent.

[0018] The optimal regeneration scheme of the present invention comprehensively considers the macro-micro performance recovery effect of high-viscosity asphalt, and the regeneration scheme is more scientific and reasonable. At the same time, the method reduces the dimension and clusters the regeneration performance index data set based on mathematical statistical methods, while ensuring the high reliability of the results, effectively avoiding the confusion of evaluation results caused by the numerous performance evaluation indicators. In addition, the regeneration scheme determination method has simple steps, strong operability, accurate and reasonable results, can meet the needs of actual projects, and is suitable for wide promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0020] Figure 1 This is a flow chart of the method for determining the best regeneration solution for aged high-viscosity asphalt of the present invention;

[0021] Figure 2 The main rheological curve of the regenerated high-viscosity asphalt in the embodiment of the present invention;

[0022] Figure 3 GR parameters for the anti-cracking of regenerated high-viscosity asphalt in the embodiment of the present invention;

[0023] Figure 4 is the viscoelastic transition temperature of the regenerated high-viscosity asphalt in the embodiment of the present invention;

[0024] Figure 5 The MSCR test results of the regenerated high-viscosity asphalt in the embodiment of the present invention;

[0025] Figure 6 The force-ductility test result of the regenerated high-viscosity asphalt in the embodiment of the present invention;

[0026] Figure 7 This is the molecular weight distribution curve of the regenerated high-viscosity asphalt in the embodiment of the present invention;

[0027] Figure 8 is the main component contribution rate and cumulative contribution rate of the recycled high-viscosity asphalt in the embodiment of the present invention;

[0028] Fig. 9 This is a main component score diagram of regenerated high-viscosity asphalt in an embodiment of the present invention;

[0029] Fig.10 It is a pedigree diagram and cluster analysis results of the cluster analysis of the method for determining the best regeneration scheme in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Embodiment 1:

[0033] The embodiment of the present invention provides a method for determining the best regeneration scheme for aged high-viscosity asphalt. According to the degree of aging of the high-viscosity asphalt, multiple different types of regeneration agents are selected, and their dosage ranges are determined to prepare multiple regenerated high-viscosity asphalts; the regeneration performance of the regenerated high-viscosity asphalt is tested based on macro-rheological tests and micro-component composition tests to obtain a data set of performance evaluation indicators for the regenerated high-viscosity asphalt; based on principal component analysis, the performance data set is reduced in dimension to be converted into principal components that can reflect most of the information of the original data; based on system clustering analysis, the principal component score points are clustered to determine the regenerated high-viscosity asphalt with the same cluster as the original high-viscosity asphalt, that is, the best regeneration scheme is obtained, such as Figure 1 As shown, the following steps are included:

[0034] (1) Preparation of recycled high-viscosity asphalt

[0035] Aged high-viscosity asphalt is obtained by on-site core sample extraction and recovery or indoor accelerated aging test. After aging, the high-viscosity asphalt is uniformly collected and heated and stirred evenly to obtain aged high-viscosity asphalt with uniform and stable performance. The aged high-viscosity asphalt is regenerated by light component-based regeneration agent and polymer-based regeneration agent, and the amount of regeneration agent is 4%, 8% and 12% of the mass of the aged high-viscosity asphalt. The light component-based regeneration agent includes petroleum-based regeneration agent (such as aromatic oil, rubber oil, engine oil, etc.) and bio-based regeneration agent (such as waste cooking oil, vegetable oil, etc.). In addition to the light component, the polymer-based regeneration agent also includes polymers (SBS, SBR, rubber powder, high-viscosity modifiers, etc.), plasticizers, and anti-aging agents. The regenerated high-viscosity asphalt is prepared according to the following steps: first, the aged high-viscosity asphalt is heated to a fluid state at 160°C, and then a specified mass of regeneration agent is added, and stirred at a speed of 500r / min for 30 minutes to obtain the regenerated high-viscosity asphalt.

[0036] (2) Performance test of recycled high-viscosity asphalt

[0037] Based on the dynamic shear rheological test, the frequency sweep test of the recycled high-viscosity asphalt was carried out to construct the rheological master curve of the recycled high-viscosity asphalt, and the phase angle master curve platform, the frequency value of the phase angle platform area, the phase angle difference in the platform area, and the GR parameter were obtained; based on the dynamic shear rheological test, the temperature sweep test of the recycled high-viscosity asphalt was carried out to test the viscoelastic transition temperature of the high-viscosity asphalt; based on the multiple stress repeated creep test, the elastic recovery performance and high-temperature permanent deformation resistance of the recycled high-viscosity asphalt were tested to obtain the strain recovery rate and irrecoverable creep compliance; based on the low-temperature force-ductility test, the fracture ductility and low-temperature toughness of the recycled high-viscosity asphalt were obtained; based on the gel permeation chromatography test, the polymer peak elution time and the corresponding molecular weight of the polymer peak of the recycled high-viscosity asphalt were tested. Finally, a set of evaluation indicators for the regeneration performance of the recycled high-viscosity asphalt was constructed.

[0038] (3) Dimensionality reduction of regeneration performance index data based on principal component analysis

[0039] Based on principal component analysis, the regeneration performance evaluation index data set of regenerated high-viscosity asphalt is linearly changed, and its dimension is reduced to a limited, linearly unrelated principal component that can reflect most of the information of the original data set, thereby simplifying the evaluation process of the regeneration effect of high-viscosity asphalt. The calculation steps of principal component analysis are as follows:

[0040] ① Construction of sample matrix x: Assuming there are n types of recycled high-viscosity asphalt and p recycling performance indicators, an n×p sample matrix x can be constructed, as shown in Formula 1.

[0041]

[0042] ② Standardization: The purpose of standardization is to eliminate the impact of the magnitude differences between different regeneration performance indicators, while ensuring that the coordinate axis is located at the center of the data point. First, calculate the mean of the regeneration performance indicator by column. and standard deviation S j (Formula 2, Formula 3), and then calculate the standardized data X according to Formula 4 ij The form of the original matrix after normalization is shown in Formula 5.

[0043]

[0044] ③ Calculate the covariance matrix of the standardized sample matrix, as shown in Formula 6.

[0045]

[0046] ④ Calculate the eigenvalues ​​and eigenvectors of the covariance matrix, as shown in Equation 7-Equation 8.

[0047] Eigenvalue: λ1≥λ2≥L≥λ p ≥0(7)

[0048] Eigenvectors:

[0049] ⑤ Calculate the principal component contribution rate CR and the cumulative contribution rate CCR, as shown in Formula 9 and Formula 10.

[0050]

[0051] ⑥ Selection of principal components: Take the first, second, ..., mth (m≤p) principal components corresponding to the eigenvalues ​​with cumulative contribution rates greater than 80%. The principal component is a linear combination of all evaluation indicators, and its expression is shown in Formula 11. For a principal component, the larger the coefficient in front of the performance indicator, the greater the impact of the performance indicator on the principal component. In general, 2 or 3 principal components are usually selected for result visualization analysis.

[0052] PC i =a 1i X1+a 2i X2+L+a pi X p (i=1,2,L,m) (11)

[0053] (4) Determination of the optimal regeneration scheme based on system cluster analysis

[0054] According to the principal component data, a systematic cluster analysis is used to combine and classify different recycled high-viscosity asphalts by comparing the distances between the principal component score points of different recycled high-viscosity asphalts, and the recycled high-viscosity asphalts are divided into several clusters with similar characteristics. First, the initial clusters and distance measurement methods are assigned, such as Euclidean distance, Manhattan distance, etc.; then, the distances between all cluster variable data points are calculated, and the most similar clusters are merged iteratively until the stopping criteria are met (such as the number of clusters reaches a predetermined value). The number of clusters should generally be determined based on the number of high-viscosity asphalt regeneration schemes and the distribution of principal component score points. Finally, the recycled high-viscosity asphalt that belongs to the same cluster as the original high-viscosity asphalt is found, which is the best regeneration scheme. The best regeneration scheme should include the best regeneration agent type and the best regeneration agent dosage.

[0055] The embodiment of the present invention selects different types and dosages of regeneration agents to prepare a variety of regenerated high-viscosity asphalts; obtains a set of regeneration performance indicators based on macro-micro tests; reduces the dimension of the regeneration performance indicator set based on principal component analysis; clusters the principal component score points based on system cluster analysis, and determines that the regenerated high-viscosity asphalt that belongs to the same cluster as the original high-viscosity asphalt is the best regeneration scheme. Among them, the number of principal components is determined based on the cumulative contribution rate greater than 80%, the number of clusters is determined based on the number of high-viscosity asphalt regeneration schemes and the distribution of principal component score points, and the best regeneration scheme should include the type and dosage of regeneration agent; compared with the existing method, the method of the present invention not only takes into account the comprehensive recovery effect of macro-micro performance, but also effectively avoids the confusion of evaluation results caused by numerous performance indicators, is simple to operate, has accurate results, and is suitable for wide promotion.

[0056] Embodiment 2:

[0057] The method for determining the optimal regeneration scheme for aged high-viscosity asphalt based on principal component analysis and system cluster analysis in this embodiment includes the following steps:

[0058] (1) Preparation of recycled high-viscosity asphalt

[0059] Based on the indoor accelerated pressure vessel aging equipment, the aging test of high-viscosity asphalt samples was carried out. After aging, the high-viscosity asphalt was uniformly collected, heated and stirred evenly, and aged high-viscosity asphalt with uniform and stable performance was obtained. Light component-based regeneration agents and polymer-based regeneration agents were selected to regenerate the aged high-viscosity asphalt. The light component-based regeneration agents were selected as furfural extracted oil, rubber oil and waste cooking oil, named A, B and C regeneration agents respectively, and the polymer-based regeneration agent was composed of SBS, light oil (furfural extracted oil, rubber oil, waste cooking oil), plasticizer and anti-aging agent, named D, E and F regeneration agents respectively, and the specific material ratio was SBS: light oil: plasticizer: anti-aging agent = 69.0%: 10.3%: 13.8%: 6.9%. The preparation process of regenerated high-viscosity asphalt is as follows: First, the aged high-viscosity asphalt is heated to a fluid state at 160°C, and then a specified mass of light component-based regeneration agent or polymer-based regeneration agent is added, and stirred at a speed of 500r / min for 30 minutes to obtain regenerated high-viscosity asphalt. The dosage of regeneration agent is 4%, 8% and 12% of the mass of aged high-viscosity asphalt respectively.

[0060] (2) Performance test of recycled high-viscosity asphalt

[0061] Based on the dynamic shear rheological test, a frequency sweep test of 0.1Hz-30 Hz was carried out on the recycled and original high-viscosity asphalt. The temperature of the frequency sweep test was set to 15℃, 25℃, 35℃, 45℃, 55℃, 65℃, and 75℃. In order to ensure that the test was within the linear viscoelastic range of high-viscosity asphalt, the strain of the frequency sweep test was 0.15% at 15℃ and 25℃; the strain of the frequency sweep test was 1.5% within 35℃-75℃. The complex modulus |G*| and phase angle δ of the high-viscosity asphalt during the frequency sweep process were recorded. At a reference temperature of 45℃, the master curves of the complex modulus and phase angle of high-viscosity asphalt were constructed. The complex modulus master curve was constructed using the sigmoid model (Equation 12), and the phase angle master curve was constructed using the double-logistic (DL) model (Equation 13). The transfer factor of the phase angle master curve was consistent with the complex modulus master curve. The construction results of the complex modulus and phase angle master curves of the recycled and original high-viscosity asphalt are shown in Figure 1. Figure 2 According to the results of the rheological master curve, the phase angle master curve platform values ​​(δ p ), phase angle platform frequency value (logf p ), the phase angle difference in the platform area (Δδ), as shown in Table 1.

[0062]

[0063] In formula 12, f r is the frequency reduction (Hz), δ is the low asymptote, α is the difference between the high and low asymptotes, β and γ are shape parameters, β represents the horizontal position of the turning point of the curve, and γ represents the slope of the mid-frequency asymptote.

[0064] In formula 13, δ is the phase angle (°), f r To reduce the frequency (Hz), f p is the frequency (Hz) at which the phase angle reaches the plateau region, δ p is the phase angle of the platform area (°), S R ,S L ,δ L is the shape parameter, S R Controls the rate at which high frequencies approach the asymptote, S L Controls the rate at which the low frequency approaches the asymptote, δ L Controls the amplitude of the phase angle change at low frequencies, H(f r -f p ) and H(f p -f r ) is the Heaviside step function.

[0065] Table 1

[0066]

[0067]

[0068] Based on the frequency sweep test data, the master curve of complex modulus and phase angle at a reference temperature of 15°C was constructed, and the complex modulus and phase angle at 15°C and 0.005 rad / s were determined. The GR parameters of the recycled and original high-viscosity asphalt were calculated according to formula 14, as shown in Table 2. The position of its GR parameter in the black spot diagram is shown in Figure 3 shown.

[0069]

[0070] In formula (14), GR is the GR parameter (kPa), |G * | is the complex modulus (kPa), δ is the phase angle (°).

[0071] Table 2

[0072] High viscosity asphalt type GR parameter (kPa) High viscosity asphalt type GR parameter (kPa) 4% A regeneration 152.0 4% D regeneration 157.0 8% A regeneration 68.0 8% D regeneration 75.5 12% A regeneration 42.8 12% D regeneration 40.7 4% B regeneration 155.4 4% E regeneration 148.4 8% B regeneration 69.8 8% E regeneration 65.3 12% B regeneration 29.4 12% E regeneration 38.3 4% C regeneration 29.7 4% F regeneration 83.0 8% C regeneration 11.6 8% F regeneration 19.2 12% C regeneration 2.9 12% F regeneration 8.6 As is 26.4

[0073] Based on the dynamic shear rheology test, the recycled and original high-viscosity asphalt was subjected to a 15℃-25℃ temperature sweep test. The frequency of the temperature sweep test was 10Hz, the high temperature (25℃-75℃) strain level was 1.5%, and the low temperature (15℃-25℃) strain level was 0.15%. Based on the complex modulus and phase angle data, the storage modulus G' and loss modulus G" of the high-viscosity asphalt were calculated. Based on the intersection of the G' curve and the G" curve, the viscoelastic transition temperature of the recycled and original high-viscosity asphalt was determined, such as Figure 4 shown.

[0074] The elastic recovery performance and high temperature resistance to permanent deformation of recycled and original high-viscosity asphalt were studied based on multiple stress repeated creep tests. The test temperature was 82°C, and the performance index measured was the strain recovery rate R at 3.2 kPa. 3.2 and irreversible creep compliance J nr3.2 , the results are as follows Figure 5 shown.

[0075] Based on the force-ductility test, the low-temperature deformation capacity of recycled and original high-viscosity asphalt at 5°C was studied. The low-temperature force-displacement curves are shown in Figure 6 As shown in the figure, the performance index measured is the fracture ductility (D d ) and low temperature toughness (S cd ), and the results are shown in Table 3.

[0076] Table 3

[0077] High viscosity asphalt type <![CDATA[D d (cm)]]> <![CDATA[S cd (N·cm)]]> 4% A regeneration 2.8 0 8% A regeneration 27.2 764 12% A regeneration 43 874 4% B regeneration 24.9 393 8% B regeneration 36.4 625 12% B regeneration 51.7 586 4% C regeneration 38.2 458 8% C regeneration 45.2 356 12% C regeneration 48.8 157 4% D regeneration 4.6 0 8% D regeneration 53.2 1530 12% D regeneration 61.9 1595 4% E regeneration 48.9 1498 8% E regeneration 77 1717 12% E regeneration 78.9 1101 4% F regeneration 33.2 496 8% F regeneration 45.1 476 12% F regeneration 65 528 As is 51.8 1813

[0078] The molecular weight distribution curves of regenerated and original high-viscosity asphalt were tested based on gel chromatography test, such as Figure 7 According to the molecular weight distribution curve, the polymer peak elution time (t p ), the corresponding molecular weight of the polymer peak (M p ) and other performance indicators, as shown in Table 4.

[0079] Table 4

[0080]

[0081]

[0082] In summary, according to the above macro and micro test results, there are 18 recycled high-viscosity asphalts and 1 original high-viscosity asphalt, and there are 11 recycling performance evaluation indicators, as shown in Table 5.

[0083] Table 5

[0084]

[0085] (3) Dimensionality reduction of regeneration performance index data based on principal component analysis

[0086] As shown in Table 5, the sample matrix dimension in principal component analysis is 19 × 11. The sample matrix is ​​standardized, and then the covariance matrix, eigenvalues ​​and eigenvectors of the standardized sample matrix are calculated. Finally, the principal component contribution rate CR and cumulative contribution rate CRR are calculated based on the eigenvalues, as follows: Figure 8 As shown. Figure 8 It can be seen that the cumulative contribution rate of the first three principal components reaches 86.3%. This shows that the original variable information can be well summarized. Therefore, the first three principal components (PC1, PC2, PC3) are used to effectively describe the performance of recycled high-viscosity asphalt. After using the first three principal components, the principal component score of recycled high-viscosity asphalt is shown in the figure below: Fig. 9 shown.

[0087] (4) Determination of the optimal regeneration scheme based on system cluster analysis

[0088] The principal component score graph is subjected to a systematic cluster analysis to determine the regenerated cluster that is closest to the original high-viscosity asphalt performance. In this embodiment, the number of clusters is set to 8, and the pedigree diagram of the cluster analysis is as follows: Fig.10 The cluster analysis results are shown in Fig.10 As shown. Fig.10 It can be seen that 12%E recycled high-viscosity asphalt and 8%E recycled high-viscosity asphalt belong to the same cluster as the original high-viscosity asphalt, which shows that the polymer furfural extracted oil-based regeneration agent is the best regeneration agent for aged high-viscosity asphalt, and the optimal regeneration agent dosage is 12% and 8%.

[0089] In summary, in this embodiment, the best regeneration scheme for aged high-viscosity asphalt is to add 12% or 8% of the polymer furfural extraction oil-based regeneration agent, which can restore the macro and micro properties of the aged high-viscosity asphalt to the original level to the greatest extent.

[0090] The embodiments described above are only descriptions of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for determining the best regeneration scheme for aged high-viscosity asphalt, characterized in that: include: Select different types and dosages of regeneration agents to prepare a variety of regenerated high-viscosity asphalts; Get the regeneration performance index set; Based on principal component analysis, the dimension of the regeneration performance index set is reduced, and the performance evaluation index set is converted into limited principal components; Based on the system cluster analysis, the principal component score points are clustered to determine the recycled high-viscosity asphalt that belongs to the same cluster as the original high-viscosity asphalt, which is the best regeneration solution.

2. The method for determining the optimal regeneration scheme for aged high-viscosity asphalt according to claim 1, characterized in that: The types of regeneration agents include light component-based regeneration agents and polymer-based regeneration agents, and the dosage of the regeneration agents is 4%, 8% and 12% of the mass of the aged high-viscosity asphalt.

3. The method for determining the optimal regeneration scheme for aged high-viscosity asphalt according to claim 2, characterized in that: The regeneration performance evaluation index includes: phase angle main curve platform, phase angle platform area frequency value, platform area phase angle difference, viscoelastic transition temperature, strain recovery rate, irreversible creep compliance, GR parameter, fracture ductility, low temperature toughness index, polymer peak elution time, and polymer peak corresponding molecular weight.

4. The method for determining the optimal regeneration scheme for aged high-viscosity asphalt according to claim 3, characterized in that: The system cluster analysis combines and classifies different recycled high-viscosity asphalts by comparing the distances between the main component score points of different recycled high-viscosity asphalts. The number of clusters is determined comprehensively based on the number of high-viscosity asphalt recycling schemes and the distribution of the main component score points.

5. The method for determining the optimal regeneration scheme for aged high-viscosity asphalt according to claim 4, characterized in that: The optimal regeneration scheme includes: the type and dosage of the regeneration agent.

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