Multi-index quantitative evaluation method for performance of bio-oil regenerant

Abstract

This application relates to the field of rejuvenator performance testing technology, and particularly to a multi-index quantitative evaluation method for the performance of bio-oil rejuvenators. The method includes: obtaining control group and test group samples of modified asphalt, wherein the control group samples are continuously aged samples without the rejuvenator to be evaluated, and the test group samples are aged samples with the rejuvenator to be evaluated added during the aging process; using an aging node where the total cumulative aging time of the control group and test group samples is the same; collecting multiple performance indicators of the control group and test group samples at the aging node; calculating the performance change rate based on the difference in performance indicators between the two groups of samples; and evaluating the rejuvenator to be evaluated based on the performance change rate. This application improves the comprehensiveness of bio-oil rejuvenator evaluation.

Description

Technical Field

[0001] This application relates to the field of regenerator performance testing technology, and in particular to a multi-index quantitative evaluation method for the performance of bio-oil regenerators. Background Technology

[0002] Asphalt materials are widely used in road construction due to their excellent bonding, waterproofing, and mechanical properties. However, with increasing road service life, asphalt is subjected to the combined effects of high temperatures, oxygen, ultraviolet radiation, moisture, and vehicle loads. This leads to the continuous volatilization of its lightweight components and ongoing oxidation, resulting in hardening, embrittlement, and a decline in viscoelastic properties. Ultimately, this affects the pavement's high-temperature rutting resistance, low-temperature crack resistance, and fatigue life. For road projects using SBS (styrene-butadiene-styrene block copolymer) modified asphalt or recycled asphalt, the aging process involves not only oxidation of the asphalt matrix but also changes in polymer structure and the attenuation of rejuvenating agent effectiveness. Therefore, accurately evaluating the performance evolution of asphalt materials during the aging process is crucial for rejuvenating agent selection, formulation optimization, and road durability prediction.

[0003] Currently, various testing methods exist for evaluating the aging performance of asphalt. For example, existing technologies use physical or rheological indicators such as penetration, softening point, ductility, rotational viscosity, complex modulus, and phase angle to evaluate the degree of asphalt aging. Other technologies establish stress-strain curves, extract parameters such as peak stress, initial modulus, and yield strength, and combine them with the analytic hierarchy process (AHP) to form a comprehensive evaluation index to assess the anti-aging performance of SBS-modified asphalt. Still other technologies collect multiple performance indicators and use principal component analysis to construct a comprehensive aging evaluation index to characterize the degree of thermo-oxidative aging of asphalt materials. All of these methods can reflect the performance changes of asphalt materials during the aging process from different perspectives and have certain reference value for evaluating the performance of asphalt materials.

[0004] Existing evaluation methods typically compare performance before and after recycling. For example, using penetration as an example, the penetration of aged asphalt is used as the performance parameter before recycling, and the penetration after adding a recycling agent is used as the performance parameter after recycling. If the penetration increases, the recycling agent is considered to have a better recovery effect. Alternatively, indicators such as complex modulus, phase angle, and fatigue life are used as evaluation objects, and the changes in the corresponding indicators before and after recycling are compared to evaluate the recycling performance of the recycling agent. However, there is a lack of comparison with continuously aged samples under the same cumulative aging conditions. Therefore, it is difficult to determine whether the performance changes during the secondary aging process after recycling come from the initial recovery effect of the recycling agent or from its improvement on the subsequent aging rate, making it impossible to conduct a more comprehensive and accurate evaluation of the recycling agent performance. Summary of the Invention

[0005] To address the problem that related technologies cannot comprehensively evaluate the quality of bio-oil regenerators, this application provides a multi-index quantitative evaluation method for the performance of bio-oil regenerators.

[0006] Firstly, this application provides a multi-index quantitative evaluation method for the performance of bio-oil regenerators, employing the following technical solution: A multi-index quantitative evaluation method for the performance of bio-oil regenerators includes: obtaining control group samples and test group samples of modified asphalt, wherein the control group samples are continuously aged samples without the regenerator to be evaluated, and the test group samples are aged samples with the regenerator to be evaluated added during the aging process. The aging node is defined as the time point at which the total cumulative aging time of the control group sample and the test group sample is the same; at the aging node, multiple performance indicators of the control group sample and the test group sample are collected. The performance change rate is calculated based on the difference in performance indicators between the two groups of samples, and the regenerant to be evaluated is assessed based on the performance change rate.

[0007] By constructing a parallel comparison between a control group without bio-oil and an experimental group regenerated with bio-oil, both with the same total cumulative aging time, this application can separate the contribution of the regenerator at different stages of the long-term aging process from the aging effect of the asphalt itself. This allows for an effective distinction between the regenerator's improvement on the initial performance of asphalt and its long-term regulation of the secondary aging rate in real road service scenarios. This provides an accurate quantitative assessment basis for the scientific screening, dosage optimization, and long-term durability prediction of bio-oil regenerators in practical engineering. In actual engineering, this can reduce the occurrence of early cracking and fatigue failure of pavement due to inaccurate evaluation.

[0008] Optionally, the control group sample includes a first control sample and a second control sample, and the test group sample includes at least a first test sample and a second test sample; The first control sample and the first test sample correspond to the first aging node, the second control sample and the second test sample correspond to the second aging node, and the total cumulative aging time of the second aging node is greater than the total cumulative aging time of the first aging node.

[0009] Setting up at least two nodes with different total cumulative aging times for dynamic comparative testing can further track and reveal the evolution of the regenerator's effect as the road service time increases, thereby more accurately capturing the dynamic differences in the impact of the regenerator on the long-term performance of the pavement at different aging stages in practical applications.

[0010] Optionally, the control group samples are obtained based on the RTFOT and PAV coupled aging process; the total cumulative aging time of the first control sample is 40h, and the total cumulative aging time of the second control sample is 60h.

[0011] The specific aging process and two key time points of 40h and 60h were clarified for the control group under the coupling of rotating film oven and pressure aging container. This design can realistically reproduce the real thermo-oxidative aging environment during road paving construction and subsequent long-term service.

[0012] Optionally, the test samples are obtained by adding a bio-oil regenerator and undergoing a second aging process after completing the first aging based on the RTFOT and PAV coupled aging process; the duration of the first aging is 20 hours; the duration of the second aging of the first test sample is 20 hours, and the duration of the second aging of the second test sample is 40 hours.

[0013] The test group was first aged for 20 hours to simulate the service state of the old material before milling, and then a recycling agent was added and a second aging process of different durations was applied. This sampling method completely reproduced the real engineering process of "early aging - recycling - re-service" of old asphalt pavement.

[0014] Optionally, performance metrics include multiple dimensions: High-temperature application dimension: dynamic viscosity at 135℃; dynamic viscoelastic dimension index: 10 at 25℃ 4 rad / s high-frequency complex modulus, 10 at 25℃ - ² rad / s low-frequency complex modulus, high-frequency phase angle and low-frequency phase angle; Rheological dimensions of road applications: rutting factor at 64℃, fatigue factor at 22℃ and low-temperature bending cracking index; Microscopic chemical dimension: carbonyl index (CI) and molecular weight distribution index (PDI).

[0015] This application considers multiple performance indicators across four dimensions: high-temperature construction, dynamic viscoelasticity, road rheology, and microchemistry. Compared to traditional single-dimensional penetration or softening point tests, this application comprehensively reflects the real-world service condition of recycled asphalt under complex climates and traffic loads, from macroscopic mechanical properties to microscopic molecular structure, ensuring the comprehensiveness and engineering reliability of the final evaluation conclusions. Optionally, for any performance index, the difference between the performance index of the test group sample and the control group sample is calculated, and the ratio of this difference to the performance index of the control group is taken as the performance change rate.

[0016] By constructing a calculation model for the performance change rate using the difference and the benchmark ratio, the performance drift interference caused by the continuous aging of the base asphalt itself is effectively eliminated.

[0017] Optionally, the regenerant to be evaluated is assessed based on the performance change rate, including: comparing multiple performance indicators with preset evaluation conditions of multiple dimensions, and determining the regenerant to be qualified in response to meeting all evaluation conditions.

[0018] The evaluation method that uses a multi-dimensional performance index to comprehensively compare and evaluate the conditions is more effective than the method of recognizing a single index as sufficient. This method can effectively reduce the problem of recycling agents performing well in a single performance aspect while other key performance aspects are severely degraded in actual material selection, and ensure that the recycling agents selected in the end have comprehensive and balanced road performance.

[0019] Optionally, the evaluation criteria include: The performance change rate corresponding to the low-frequency complex modulus at the second aging node is less than the first preset value, indicating that the bio-oil has reduced the long-term stiffness of the asphalt and restored its plastic deformation capacity. If the rate of change of performance corresponding to the high-frequency complex modulus of the second aging node is within the preset range, it is determined that the high-temperature stiffness remains stable.

[0020] By combining the long-term significant decrease in low-frequency complex modulus with the short-term stability of high-frequency complex modulus, high-quality recyclers can be accurately identified in engineering applications that can effectively restore the plastic deformation capacity of aged asphalt without weakening the high-temperature rutting stiffness of asphalt.

[0021] Optionally, the evaluation criteria also include: the carbonyl index performance change rate at the first aging node is negative, and the carbonyl index performance change rate at the second aging node is positive, indicating that the regenerator inhibits asphalt oxidation in the short term.

[0022] By tracking the changes in carbonyl index from negative to positive at different aging stages, the true inhibitory ability of regenerators on asphalt oxidation rate was revealed from the microscopic mechanism of molecular structure anti-oxidation, providing a basis for predicting the anti-aging life of recycled pavement under natural environments with strong ultraviolet radiation and high oxygen exposure.

[0023] Optionally, the evaluation criteria also include: the fatigue factor performance change rate at both the first and second aging nodes is negative, and the performance change rate at the second aging node is less than that at the first aging node, thus determining that the regenerator has a long-term effect of improving fatigue resistance.

[0024] This application has the following technical effects: A continuous aging control group with aligned total cumulative aging time and a secondary aging test group with added rejuvenator were constructed. By collecting multiple indicators at the same node and calculating the performance change rate, the net effect of the bio-oil rejuvenator was separated from the influence of asphalt's own aging. Compared with the simple comparison before and after traditional recycling, this application further combines construction fluidity, viscoelastic properties, road rheology, and microchemical indicators to comprehensively evaluate the quality of the rejuvenator from the perspectives of physical softening, molecular reconstruction, and performance regulation. This provides a standardized and quantitative method for rejuvenator screening, formulation optimization, and prediction of the long-term durability of recycled pavements. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of a multi-index quantitative evaluation method for the performance of bio-oil regenerators according to embodiments of this application.

[0026] Figure 2 This is an example chart of measured data from the multi-index quantitative evaluation method for the performance of bio-oil regenerators in this application. Detailed Implementation

[0027] This application discloses a multi-index quantitative evaluation method for the performance of bio-oil regenerators.

[0028] Reference Figure 1 The multi-index quantitative evaluation method for the performance of bio-oil regenerators includes steps S1-S3.

[0029] S1. Obtain control group samples and test group samples of modified asphalt. The control group samples are continuously aged samples without the recycling agent to be evaluated, and the test group samples are aged samples with the recycling agent to be evaluated added during the aging process.

[0030] In this step, two sets of samples were prepared using SBS modified asphalt of the same origin, and the total cumulative aging time of the two sets of samples was controlled at the same aging node.

[0031] The two groups of samples were a control sample and an experimental sample. The control sample was a continuously aged sample. The experimental sample was a sample that underwent one aging process, was regenerated by adding bio-oil, and then underwent a second aging process.

[0032] The control samples consist of two samples, differing only in their aging duration. For ease of description, the two samples in the control group are designated as the first control sample and the second control sample, respectively.

[0033] The first control sample was subjected to an RTFOT+PAV coupled aging process, and a total cumulative aging of 40 hours was completed.

[0034] The second control sample was subjected to an RTFOT+PAV coupled aging process, and a total cumulative aging of 60 hours was completed.

[0035] The RTFOT+PAV coupled aging process is as follows: SBS modified asphalt is placed in a rotating thin film oven and aged for a short period (e.g., 85 minutes) according to JTG3410-2025 T0610 to obtain short-term aged asphalt; then it is transferred to a pressure aging vessel and subjected to long-term PAV (Pressure Aging Vessel) aging at 100℃ and 2.1MPa according to JTG 3410-2025T0630. The total duration of the two aging processes is 40h or 60h, and no bio-oil regeneration agent is added throughout the process.

[0036] The test group also includes two test specimens. For ease of description, the two test specimens are defined as the first test specimen and the second test specimen.

[0037] Both the first and second test samples underwent two aging processes, with the difference being the duration of the second aging process.

[0038] For the first test sample, the homologous SBS modified asphalt was first aged for 20 hours using RTFOT coupled with PAV to simulate the pre-service aging of the old material before milling. Then, bio-oil regenerator was added to the temperature-controlled mixing device by external admixture method. The amount of regenerator was 5% in this example, and it was stirred at 145°C for 20 minutes to fully disperse it, thus obtaining bio-oil regenerated asphalt. Subsequently, the regenerated asphalt was subjected to a second aging process using RTFOT coupled with PAV, with the second PAV duration being 20 hours.

[0039] For the second test sample, the homologous SBS modified asphalt was first aged for 20 hours using RTFOT coupled with PAV to simulate the pre-service aging of the old material before milling. Then, bio-oil regenerator was added to the temperature-controlled mixing device using the external admixture method. The amount of regenerator was 5% in this example, and the mixture was stirred at 145°C for 20 minutes to ensure full dispersion, thus obtaining bio-oil regenerated asphalt. Subsequently, the regenerated asphalt was subjected to a second aging process using RTFOT coupled with PAV, with the second PAV duration being 40 hours.

[0040] In another embodiment, the aging time can also be adjusted from 20 hours to 40 hours to simulate the recycling conditions of old materials with a deeper degree of aging in the early service stage, and the adjustment does not change the core feature that the total cumulative aging time of the two paths is aligned with each other.

[0041] It is understandable that, apart from the variable of whether or not bio-oil rejuvenator was added, the control group and the experimental group had completely identical asphalt raw materials, SBS content, shear preparation process, temperature parameters, and total cumulative aging time. This step, through a dual-path design that aligns the total cumulative aging time, ensures that the aging effects of the asphalt substrate and SBS itself occur simultaneously in the control group and the experimental group, laying the foundation for the subsequent separate separation of the rejuvenator contribution.

[0042] S2. The time aging node with the same total cumulative aging time for the control group sample and the test group sample is taken as the aging node; at the aging node, multiple performance indicators of the control group sample and the test group sample are collected.

[0043] The performance indicators include ten performance indicators across four dimensions: high-temperature construction, dynamic viscoelasticity, road rheology, and microchemistry.

[0044] The first and second control samples and the first and second test samples were tested at two aging points: 40 hours and 60 hours.

[0045] For high-temperature construction: dynamic viscosity at 135℃. Asphalt is a fluid at high temperatures. It is measured by a rotational viscometer to characterize the flow and coating capacity of asphalt during high-temperature mixing and construction.

[0046] For the dynamic viscoelastic dimension: a dual-frequency scan was performed at 25°C using a DSR (Dynamic Shear Rheometer), with the high frequency fixed. With low frequency Two points were used to collect the complex modulus. With phase angle The former reflects the total stiffness of asphalt at the corresponding frequency, while the latter reflects the proportion of viscous and elastic components. High-frequency points correspond to short-term (rapid) loading behavior, while low-frequency points correspond to long-term (slow) loading behavior.

[0047] For road rheological dimensions: 64℃ rutting factor, the larger the value, the stronger the resistance to permanent deformation at high temperature; 22℃ fatigue factor, the smaller the value, the stronger the resistance to fatigue cracking; and low temperature bending crack index, the closer its algebraic value is to zero, the better the low temperature crack resistance.

[0048] At the microscopic chemical level, the infrared carbonyl index (CI) is collected to characterize the degree of asphalt oxidation; the gel chromatography molecular weight distribution index (PDI) characterizes the width of the molecular weight distribution. The carbonyl index is obtained from FTIR (Fourier Transform Infrared Spectroscopy) infrared spectroscopy at 1700 cm⁻¹. -¹ Calculation of the ratio of carbonyl characteristic peak area to reference characteristic peak area; Molecular weight distribution index PDI = weight average molecular weight Mw / number average molecular weight Mn, determined by GPC (Gel Permeation Chromatography).

[0049] This step simultaneously acquires ten data points covering both macroscopic application and microscopic molecule at a unified aging node, forming a complete data base that can be compared item by item.

[0050] S3. Calculate the performance change rate based on the difference in performance indicators between the two groups of samples, and evaluate the regenerant to be evaluated based on the performance change rate.

[0051] This step receives the numerical values ​​of various indicators for the two types of samples output from step S2. To independently isolate the net contribution of the rejuvenator during secondary aging from the aging effects of the asphalt substrate and SBS itself, the indicators of the control group with the same total aging time are used as a benchmark. The deviation of the test group's indicators relative to the benchmark is quantified, and the performance change rate is constructed accordingly. For any performance indicator, its calculation formula can be expressed as: ; In the formula, Let be the rate of change of performance, and be a dimensionless percentage. This refers to the value of a certain index at a certain aging point in the bio-oil blending test group. The values ​​are for the same indicator in the control group without bio-oil at the same aging stage, and the physical units of the two values ​​depend on the corresponding indicator.

[0052] The denominator is taken from the control group baseline, when Time represents the improvement of this indicator relative to the benchmark, when The term "time-based" indicates a decrease relative to the baseline. This means that the relative increase or decrease in the index only reflects the rise or fall of the exponential value and does not directly reflect the change in asphalt performance. For example, a higher rutting factor value indicates stronger resistance to permanent deformation at high temperatures, while a lower fatigue factor value indicates stronger resistance to fatigue cracking. Here, the performance change rate is mainly used to represent the magnitude of the relative change. The larger the absolute value, the stronger the regulatory effect of the regenerant on this indicator.

[0053] The performance of bio-oil regenerators is evaluated based on the rate of performance change of each performance index at different aging stages.

[0054] In one embodiment, the performance of the bio-oil regenerator can be evaluated by comprehensively comparing multiple performance indicators with preset evaluation conditions from multiple dimensions.

[0055] At the level of physical softening, the long-term performance change rate of low-frequency complex modulus is used as the main criterion: when the performance change rate of its 60-hour aging node is less than the first preset value (set by those skilled in the art based on experience, and taken as -20% in this embodiment), it is determined that the bio-oil has reduced the long-term stiffness of asphalt and restored its plastic deformation capacity. The performance change rate corresponding to the high-frequency complex modulus at the 60-hour aging node is within the preset range (e.g., (5%), indicating that the high-temperature stiffness remains stable.

[0056] At the molecular reconstruction level, the performance change rate of PDI at both aging nodes is used as the criterion: when the performance change rate of PDI at both the 40-hour aging node and the 60-hour aging node is less than the second preset value (-20% in this embodiment), it is determined that the small molecule component of the regenerator has broken the macromolecular aggregation and optimized the molecular weight distribution. The carbonyl index is negative in the short term (i.e., at the 40-hour aging node), and the performance change rate corresponding to the 60-hour aging node is positive, indicating that the regenerator inhibits asphalt oxidation in the short term.

[0057] For example, the performance change rates of PDI at 40 hours and 60 hours were -25.64% and -24.51%, respectively, and the molecular weight distribution narrowed, indicating that the small molecule components of the regenerator broke up the macromolecular aggregation and optimized the molecular weight distribution; the performance change rate of carbonyl index at 40 hours was -2.15% and the performance change rate at 60 hours was +12.78%, showing an evolution of short-term oxidation inhibition and long-term mild recovery from oxidation, indicating that the regenerator inhibited asphalt oxidation in the short term.

[0058] At the performance control level, a balance judgment is made by comprehensively considering three factors: fatigue factor, low-temperature cracking index, and rutting factor. The performance change rate corresponding to the fatigue factor of both the 40-hour and 60-hour aging nodes is negative, and the negative value increases with the aging time. That is, the performance change rate corresponding to the 60-hour aging node is less than the performance change rate corresponding to the 40-hour aging node (for example, the performance change rate of the 60-hour aging node is -20%, and the performance change rate of the 40-hour aging node is -10%). The performance change rate of the low-temperature bending cracking index of both the 40-hour and 60-hour aging nodes is less than 0. The performance change rate corresponding to the rutting factor is negative and within a preset range (e.g., -30%-0%). It is determined that a balanced control of low-temperature crack resistance, long-term fatigue resistance improvement, and moderate softening and hardening prevention at high temperatures has been achieved.

[0059] In addition, the recycling agent can be further evaluated based on dynamic viscosity. For example, when the performance change rate of dynamic viscosity at both the 40-hour aging node and the 60-hour aging node is greater than the third preset threshold (50%), it is determined that the recycling agent will significantly increase the viscosity of asphalt, and high mixing temperature is required for construction.

[0060] In this embodiment, the bio-oil is considered qualified when the bio-oil regenerator meets all the above conditions.

[0061] Combination Figure 2 The figure shows a set of data measured for the experimental group and the control group. Combined with... Figure 2 It can be seen that, at the level of physical softening, the performance change rate at the 60-hour aging node with low-frequency complex modulus is -25.59%, indicating that bio-oil reduces the long-term stiffness of asphalt and restores its plastic deformation capacity. The performance change rates corresponding to the high-frequency complex modulus at the 40-hour and 60-hour aging nodes were 0.76% and -1.6%, respectively, both within the preset range (e.g., (5%), indicating that the high-temperature stiffness remains stable.

[0062] At this point, it can be determined that the bio-oil regenerator meets the requirements of the physical softening level.

[0063] At the molecular reconstruction level, the performance change rates of PDI at the 40-hour aging node and the 60-hour aging node were -25.64% and -24.51%, respectively; both were less than -20%, indicating that the small molecule components of the regenerator broke up the macromolecular aggregation and optimized the molecular weight distribution. The carbonyl indices at the 40-hour and 60-hour aging nodes were -2.15% and 12.78%, respectively. The carbonyl index was negative in the short term (i.e., at the 40-hour aging node), and the performance change rate at the 60-hour aging node was positive, indicating that the regenerator inhibited asphalt oxidation in the short term.

[0064] At this point, it can be determined that the bio-oil regenerator meets the requirements at the molecular reconstruction level.

[0065] In terms of performance regulation, the fatigue factors of the 40-hour aging node and the 60-hour aging node were -5.90% and -44.57%, respectively; the performance change rates of the low-temperature bending crack index of the 40-hour aging node and the 60-hour aging node were -52.70% and -65.56%, respectively; and the performance change rates of the rutting factor of the 40-hour aging node and the 60-hour aging node were -25.26% and -6.81%, respectively.

[0066] The performance change rates corresponding to the fatigue factors at both the 40-hour and 60-hour aging nodes are negative, and the negative value increases with the aging time, meaning that the performance change rate corresponding to the 60-hour aging node is less than that corresponding to the 40-hour aging node; the performance change rates of the low-temperature bending crack index at both the 40-hour and 60-hour aging nodes are less than 0; the performance change rate corresponding to the rutting factor is negative and within the range of -30% to 0%, indicating that a balanced control of low-temperature crack resistance, long-term fatigue resistance improvement, and moderate softening and hardening prevention at high temperatures has been achieved.

[0067] In addition, the dynamic viscosity at the 40-hour aging node and the 60-hour aging node were 72.94% and 124.12% respectively, indicating that the asphalt viscosity increased and high mixing temperature was required for construction.

[0068] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A multi-index quantitative evaluation method for the performance of bio-oil regeneration agents, characterized in that, include: Control group samples and test group samples of modified asphalt were obtained. The control group samples were continuously aged samples without the recycling agent to be evaluated, and the test group samples were aged samples with the recycling agent to be evaluated added during the aging process. The aging node is defined as the time point at which the total cumulative aging time of the control group sample and the test group sample is the same; at the aging node, multiple performance indicators of the control group sample and the test group sample are collected. The performance change rate is calculated based on the difference in performance indicators between the two groups of samples, and the regenerant to be evaluated is assessed based on the performance change rate.

2. The multi-index quantitative evaluation method for the performance of bio-oil regenerator according to claim 1, characterized in that, The control group samples include a first control sample and a second control sample, and the test group samples include at least a first test sample and a second test sample; The first control sample and the first test sample correspond to the first aging node, the second control sample and the second test sample correspond to the second aging node, and the total cumulative aging time of the second aging node is greater than the total cumulative aging time of the first aging node.

3. The multi-index quantitative evaluation method for the performance of bio-oil regenerator according to claim 2, characterized in that, The control group samples were obtained based on the RTFOT and PAV coupled aging process; the total cumulative aging time of the first control sample was 40h, and the total cumulative aging time of the second control sample was 60h.

4. The multi-index quantitative evaluation method for the performance of bio-oil regenerator according to claim 2, characterized in that, The test samples were obtained by first aging using the RTFOT and PAV coupled aging process, followed by the addition of a bio-oil regenerator and a second aging process. The first aging process lasted 20 hours. The second aging process for the first test sample lasted 20 hours, and the second aging process for the second test sample lasted 40 hours.

5. The multi-index quantitative evaluation method for the performance of bio-oil regenerator according to claim 1, characterized in that, Performance metrics include multiple dimensions: High-temperature application dimension: dynamic viscosity at 135℃; dynamic viscoelastic dimension index: 10 at 25℃ 4 rad / s high-frequency complex modulus, 10 at 25℃ - ² rad / s low-frequency complex modulus, high-frequency phase angle and low-frequency phase angle; Rheological dimensions of road applications: rutting factor at 64℃, fatigue factor at 22℃ and low-temperature bending cracking index; Microscopic chemical dimension: carbonyl index (CI) and molecular weight distribution index (PDI).

6. The multi-index quantitative evaluation method for the performance of bio-oil regenerator according to claim 5, characterized in that, The calculation of the performance change rate includes: for any performance index, calculating the difference between the performance index of the test group sample and the control group sample, and using the ratio of this difference to the performance index of the control group as the performance change rate.

7. The multi-index quantitative evaluation method for the performance of bio-oil regenerator according to claim 5, characterized in that, The regenerant to be evaluated is assessed based on the rate of performance change, including comparing multiple performance indicators with preset evaluation conditions of multiple dimensions, and determining the regenerant to be qualified in response to meeting all evaluation conditions.

8. The multi-index quantitative evaluation method for the performance of bio-oil regenerator according to claim 7, characterized in that, The evaluation criteria include: The performance change rate corresponding to the low-frequency complex modulus at the second aging node is less than the first preset value, indicating that the bio-oil has reduced the long-term stiffness of the asphalt and restored its plastic deformation capacity. If the rate of change of performance corresponding to the high-frequency complex modulus of the second aging node is within the preset range, it is determined that the high-temperature stiffness remains stable.

9. The multi-index quantitative evaluation method for the performance of bio-oil regenerator according to claim 7, characterized in that, The evaluation criteria also include: the carbonyl index performance change rate at the first aging node is negative, and the carbonyl index performance change rate at the second aging node is positive, indicating that the regenerator inhibits asphalt oxidation in the short term.

10. The multi-index quantitative evaluation method for the performance of bio-oil regenerator according to claim 7, characterized in that, The evaluation criteria also include: the performance change rate of fatigue factor at both the first and second aging nodes is negative, and the performance change rate at the second aging node is less than that at the first aging node, thus determining that the regenerator has a long-term effect of improving fatigue resistance.

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