Determination method of optimal construction temperature for warm-mixing synchronous regeneration of waste SBS (Styrene Butadiene Styrene) modified asphalt

Abstract

The invention relates to the technical field of road engineering, in particular to a method for determining the optimal construction temperature of warm-mixing synchronous regeneration of waste SBS (styrene butadiene styrene) modified asphalt, which comprises the following steps: customizing a two-component synchronous regeneration agent for SBS modified asphalt with different aging degrees; warm-mixing synchronous regenerated SBS modified asphalt at different temperatures is prepared, and thermal insulation treatment is performed to simulate the actual construction process; testing the typical rheological property of the warm mixing synchronous regenerated SBS modified asphalt; drawing a warm mixing synchronous regeneration temperature-rheological property scatter diagram, and constructing a corresponding fitting equation; ideal temperature intervals of high-temperature rutting resistance, medium-temperature cracking resistance and low-temperature fracture resistance are divided, and the intersection of the three temperature intervals is used as the optimal warm mixing synchronous regeneration temperature. According to the method, the warm mixing synchronous regeneration temperature can be quickly and accurately determined, the synergistic interaction effect of the double-component synchronous regeneration agent-warm mixing agent is exerted, and meanwhile, the performance loss of the regenerated asphalt mixture caused by secondary aging due to too high heating temperature is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of road engineering, and specifically relates to a method for determining the optimal construction temperature of warm-mix synchronous recycling of waste SBS modified asphalt. Background Technique

[0002] During the long-term service process of SBS modified asphalt, it will age (including the aging and hardening of the matrix asphalt component and the oxidation fracture of the SBS polymer molecular chain) due to direct contact with air, rainwater, etc. and being affected by ultraviolet radiation, resulting in rapid deterioration of performance. It is necessary to carry out renovation and reconstruction in a timely manner, and at the same time, it will also lead to the large generation of waste SBS modified asphalt mixture. Relevant statistical data shows that more than 15% of the old asphalt pavements in China need to be renovated and reconstructed every year, and the waste asphalt mixture (RAP) generated therefrom is expected to exceed 160 million tons. Among them, SBS modified asphalt pavement accounts for about 15% of the total asphalt pavement, and the waste materials generated are also very large, and high-quality recycling is urgently needed. At present, the most widely used recycling technology in China is the hot-mix recycling technology of waste asphalt mixture. According to the "Technical Specification for Construction of Highway Asphalt Pavements" (JT F40—2004) and the "Technical Specification for Highway Asphalt Pavement Recycling" (JTGT5521-2019), the discharge temperature of hot-mix recycled SBS modified asphalt mixture is usually 5-10°C higher than that of the corresponding type of ordinary hot-mix SBS modified asphalt mixture, reaching 175-195°C. At the same time, considering that the entire mixing, transportation, paving and compaction duration may be as long as 2h-4h. Obviously, such a long-term high-temperature environment will inevitably cause secondary aging of the recycled SBS modified asphalt, leading to the deterioration of its rheological properties, thereby affecting the service performance of the recycled SBS modified asphalt pavement. To avoid the adverse effects of high-temperature secondary aging, domestic and foreign scholars have proposed to introduce a warm-mix agent during the hot-mix recycling process to reduce the construction temperature, so as to achieve a large-scale warm-mix recycling of waste SBS modified asphalt mixture. Research shows that adding a warm-mix agent can reduce the construction temperature from the original 155-195°C (including the whole process of mixing, paving and compaction) to about 115-155°C.

[0003] When aging SBS modified asphalt is synchronously regenerated and repaired under simulated actual mixing conditions, a two-component synchronous regenerant (including an aging matrix asphalt component conditioner and a broken SBS molecular chain linker) needs to be added to the aging SBS modified asphalt. However, the reconditioning of the matrix asphalt component and the reconnecting of the broken SBS molecular chains in the aging SBS modified asphalt cannot be completely completed during the short mixing process (55 - 75 s). In particular, the residual broken SBS molecular chain linker in the asphalt will continue the repair reaction of the broken SBS copolymer network structure at the transportation, paving, and compaction temperatures. If the warm mixing synchronous regeneration temperature is not properly controlled, when the temperature is too low, the diffusion rate of the aging matrix asphalt component conditioner is low, and the ability to restore the stability of the aging matrix asphalt colloid structure is limited. At the same time, the reaction activity of the broken SBS molecular chain linker is also low, and it cannot effectively connect the aged and broken SBS copolymers, resulting in limited repair of the synchronous regeneration performance of the aging SBS modified asphalt and problems such as poor performance of the regenerated SBS modified asphalt pavement. When the temperature is too high, although the diffusion rate of the aging matrix asphalt component conditioner increases and the reaction activity of the broken SBS molecular chain linker improves, and the original performance of the aging SBS modified asphalt can be quickly restored, the high temperature is likely to cause secondary aging of the regenerated SBS modified asphalt. At the same time, high-temperature heating has disadvantages such as high energy consumption and large carbon emissions. Therefore, the warm mixing synchronous regeneration construction temperature of waste SBS modified asphalt needs to be accurately controlled. This temperature should not only maximize the synchronous regeneration and repair efficiency of the two-component synchronous regenerant but also avoid the performance deterioration caused by secondary aging of the regenerated asphalt due to excessive heating temperature and significantly reduce the energy consumption waste and carbon emissions caused by high-temperature construction. Based on this, a method for determining the optimal construction temperature for warm mixing synchronous regeneration of waste SBS modified asphalt is proposed. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention provides a method for determining the optimal construction temperature for warm mixing synchronous regeneration of waste SBS modified asphalt. The testing and analysis methods are simple and fast. At the optimal warm mixing synchronous regeneration temperature, the two-component regenerant can exert the maximum regeneration and repair effect, restore the original performance of the aged SBS modified asphalt, and avoid the phenomenon of secondary aging and deterioration of the regenerated SBS modified asphalt.

[0005] To achieve the above object, the present invention provides the following technical solution: A method for determining the optimal construction temperature for warm mixing synchronous regeneration of waste SBS modified asphalt, comprising the following steps,

[0006] (1) Aging the warm mixing original SBS modified asphalt, grouping the obtained aged SBS modified asphalt, and setting it aside;

[0007] (2) Heat each group of aged SBS modified asphalt to melting at different temperatures, add an aging matrix asphalt component conditioner and a broken SBS molecular chain linker, and after rapid stirring, add a warm mix additive while rapidly stirring again to obtain multiple groups of warm mix synchronous recycled SBS modified asphalt;

[0008] (3) Place each group of warm mix synchronous recycled SBS modified asphalt in an oven at different temperatures for heat preservation for 2 h to simulate the actual construction process;

[0009] (4) Test the typical rheological properties of the warm mix synchronous recycled SBS modified asphalt under different heat preservation conditions, including high temperature rutting resistance, medium temperature cracking resistance, and low temperature fracture resistance;

[0010] (5) Plot the scatter diagrams of the typical rheological properties of the warm mix synchronous recycled SBS modified asphalt under different heat preservation conditions, and simultaneously construct the corresponding fitting equations;

[0011] (6) Using the threshold values of the rheological properties of the warm mix as-received SBS modified asphalt, divide the three ideal temperature ranges corresponding to the high temperature rutting resistance, medium temperature cracking resistance, and low temperature fracture resistance of the warm mix synchronous recycled SBS modified asphalt;

[0012] (7) Take the intersection of the three ideal temperature ranges, which is the optimal construction temperature for the warm mix synchronous recycling of waste SBS modified asphalt.

[0013] Preferably, in step (2), the aging matrix asphalt component conditioner is selected from waste engine oil, aromatic oil, naphthenic oil, petroleum wax oil, cottonseed oil, compound castor oil, mustard oil, soybean oil, tall oil, cashew shell oil, and sunflower oil; the broken SBS molecular chain linker is one or more of epoxy compounds, isocyanate compounds, and polymer prepolymers; the warm mix additive is selected from organic wax-based warm mix additives and surfactant-based warm mix additives.

[0014] Preferably, in step (2), the rapid stirring time after adding the aging matrix asphalt component conditioner and the broken SBS molecular chain linker is 75 s; the rapid stirring time after adding the warm mix additive is 15 s.

[0015] Preferably, in step (2), the dosage of the aging matrix asphalt component conditioner is 4-7% of the mass of the aged SBS modified asphalt; the dosage of the broken SBS molecular chain linker is 4-6% of the mass of the aged SBS modified asphalt; the dosage of the warm mix additive is 1-3% of the mass of the aged SBS modified asphalt.

[0016] Preferably, in steps (2) to (3), the different temperatures are controlled between 115 and 195 °C, and the temperature gradient interval is 10 °C; among them, the melting temperature of the aged SBS modified asphalt is the same as the heat preservation temperature of the corresponding warm mix synchronous recycled SBS modified asphalt.

[0017] Preferably, in step (6), the unrecoverable creep compliance and 90% of the total shear strain of the warm mix virgin SBS modified asphalt are used as the high and low temperature rheological property thresholds of the warm mix synchronous regeneration SBS modified asphalt, and the G-R parameter equal to 180 kPa is used as the medium temperature rheological property threshold of the warm mix synchronous regeneration SBS modified asphalt.

[0018] Preferably, in step (6), the warm mix virgin SBS modified asphalt is prepared by adding a warm mix agent to the virgin SBS modified asphalt and rapidly stirring for 15 s at 150°C.

[0019] Preferably, according to the determined optimal construction temperature, the viscosity-temperature curve of the warm mix synchronous regeneration SBS modified asphalt at different dosages of the warm mix agent is tested and plotted, and the optimal dosage of the warm mix agent is calculated by back-calculation according to the specified optimal construction viscosity of the virgin SBS modified asphalt.

[0020] The present invention provides a method for determining the optimal construction temperature of warm mix synchronous regeneration of waste SBS modified asphalt, which has the following beneficial effects compared with the prior art:

[0021] The present invention proposes a method for determining the optimal construction temperature of warm mix synchronous regeneration of waste SBS modified asphalt. By means of typical rheological property tests, a scatter diagram of the change of warm mix synchronous regeneration temperature-rheological properties is plotted and a fitting equation is determined. Using 90% of the rheological properties of the warm mix virgin SBS modified asphalt or the existing rheological property thresholds, three ideal temperature ranges corresponding to the high temperature rutting resistance, medium temperature cracking resistance and low temperature fracture resistance of the warm mix synchronous regeneration SBS modified asphalt are divided. The optimal warm mix synchronous regeneration temperature is quantitatively determined through the three ideal temperature ranges. The test and analysis methods are simple and fast. At the optimal warm mix synchronous regeneration temperature, the two-component regenerant can exert the maximum regeneration and repair effect, restore the original properties of the aged SBS modified asphalt, and at the same time avoid the phenomenon of secondary aging and deterioration of the regenerated SBS modified asphalt.

[0022] The present invention proposes a method for determining the optimal construction temperature of warm mix synchronous regeneration of waste SBS modified asphalt. At the optimal warm mix synchronous regeneration temperature, the viscosity-temperature curve of the warm mix synchronous regeneration SBS modified asphalt at different dosages of the warm mix agent is tested and plotted. According to the optimal construction viscosity corresponding to the virgin SBS modified asphalt, the optimal dosage of the warm mix agent is quantitatively calculated, avoiding the increase in construction costs caused by excessive dosage of the warm mix agent or the insufficient temperature reduction caused by too little dosage. Description of the Drawings

[0023] The accompanying drawings described herein are used to provide a further understanding of the present application and form a part of the present application. The schematic embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:

[0024] Figure 1 It is a test chart of the high-temperature rheological properties of the warm mix synchronous recycled SBS modified asphalt in Example 1 of the present invention;

[0025] Figure 2 It is a test chart of the medium-temperature rheological properties of the warm mix synchronous recycled SBS modified asphalt in Example 1 of the present invention;

[0026] Figure 3 It is a test chart of the low-temperature rheological properties of the warm mix synchronous recycled SBS modified asphalt in Example 1 of the present invention;

[0027] Figure 4 It is a process chart for determining the optimal construction temperature of the Sasobit warm mix synchronous recycled SBS modified asphalt of the present invention;

[0028] Figure 5 It is a test chart of the rotational viscosity of the original SBS modified asphalt of the present invention;

[0029] Figure 6 It is a test chart of the rotational viscosity of the Sasobit warm mix synchronous recycled SBS modified asphalt of the present invention;

[0030] Figure 7 It is a process chart for determining the optimal construction temperature of the Evotherm warm mix synchronous recycled SBS modified asphalt of the present invention;

[0031] Figure 8 It is a test chart of the rotational viscosity of the Evotherm warm mix synchronous recycled SBS modified asphalt of the present invention. Detailed implementation manners

[0032] The following embodiments are used to detail the implementation manners of the present application, so as to fully understand how the present application uses technical means to solve technical problems and achieve the realization process of technical effects and implement accordingly.

[0033] Example 1

[0034] In this embodiment, the unaged original asphalt used is SBS I-D modified asphalt. The SBS polymer modifier is linear, the ratio of polystyrene / polybutadiene block (S / B) is 3:7, and the dosage is 5% of the matrix asphalt dosage. The artificial-aged SBS modified asphalt is prepared by subjecting the original SBS modified asphalt to Rotating Thin Film Oven Aging (RTFO) + 40h Extended Pressure Aging Vessel (PAV), which can simulate the aged asphalt in the actual service state for 6 - 8 years. To restore the original performance of the aged SBS modified asphalt, aromatic oil is used as the aging matrix asphalt component conditioner in this embodiment, and the isocyanate compound triallyl isocyanurate (TAIC) is used as the SBS molecular chain breaking linker. To reduce the hot mix recycling temperature, the organic wax Sasobit is selected as the warm mix agent.

[0035] A method for determining the optimal construction temperature of warm mix synchronous recycling of waste SBS modified asphalt, comprising the following steps:

[0036] (1) Group the RTFO + 40h PAV aged SBS modified asphalt into a total of 9 groups, which are sequentially designated as sample - 1, sample - 2, sample - 3, sample - 4, sample - 5, sample - 6, sample - 7, sample - 8, and sample - 9 for standby;

[0037] (2) Customize a two-component rejuvenator for the RTFO + 40h PAV aged SBS modified asphalt. Referring to Chinese invention patent CN118069976A, according to the aging loss and rejuvenation recovery of the infrared spectral characteristic peak area ratios related to the light components of the matrix asphalt and SBS copolymer before and after the aging and rejuvenation of the SBS modified asphalt, the optimal dosages of aromatic oil and TAIC are determined to be 6.96wt% and 5.05wt%;

[0038] (3) Heat the RTFO + 40h PAV aged SBS modified asphalt to melting at 115 - 195 °C (during which, control the melting temperature of sample - 1 at 115 °C, the melting temperature of sample - 2 at 125 °C, the melting temperature of sample - 3 at 135 °C, the melting temperature of sample - 4 at 145 °C, the melting temperature of sample - 5 at 155 °C, the melting temperature of sample - 6 at 165 °C, the melting temperature of sample - 7 at 175 °C, the melting temperature of sample - 8 at 185 °C, and the melting temperature of sample - 9 at 195 °C), add 6.96wt% of aromatic oil and 5.05wt% of TAIC, stir rapidly for 75 s, then add 3wt% of Sasobit, and stir rapidly again for 15 s to obtain the warm mix synchronous recycled SBS modified asphalt of the corresponding groups (sequentially designated as sample - 1', sample - 2', sample - 3', sample - 4', sample - 5', sample - 6', sample - 7', sample - 8', and sample - 9');

[0039] (4) Place the prepared warm mix synchronous recycled SBS modified asphalt in an oven at 115 - 195 °C for 2 h (during which, ensure that the insulation temperature of sample - 1' is the same as the melting temperature of sample - 1, and similar treatments are applied to the remaining samples) to simulate the transportation, paving, and compaction processes of the actual warm mix synchronous recycled SBS modified asphalt mixture;

[0040] (5) Test the typical rheological properties of the warm mix synchronous recycled SBS modified asphalt under different insulation conditions. Referring to the American ASTM D7157 test specification, test its multiple stress creep recovery test (reflecting high - temperature rutting resistance), G - R parameter test (reflecting intermediate - temperature cracking resistance), and low - temperature shear creep recovery test (reflecting low - temperature fracture resistance) respectively;

[0041] (6) According to the key evaluation indexes of the high - temperature, intermediate - temperature, and low - temperature rheological property test results, draw the scatter plots of the typical rheological property changes of the warm mix synchronous recycled SBS modified asphalt under different insulation conditions, and at the same time construct the corresponding fitting equations, as shown respectively in Figures 1 to 3 where the key evaluation index of the high - temperature rheological property is the non - recoverable creep compliance (J nr3.2 ), the smaller its value represents better high - temperature rutting resistance; the key evaluation index of the intermediate - temperature rheological property is the G - R parameter, and when its value is greater than 180 kPa, it indicates that the asphalt will crack at intermediate temperature, while the key evaluation index of the low - temperature rheological property is the total shear strain, and the larger its value represents better low - temperature creep performance;

[0042] (7) Take the J nr3.2 of the warm mix as - received SBS modified asphalt and 90% of the total shear strain as the high - and low - temperature rheological property thresholds of the warm mix synchronous recycled SBS modified asphalt, and take the G - R parameter equal to 180 kPa as the intermediate - temperature rheological property threshold of the warm mix synchronous recycled SBS modified asphalt. As can be seen from Figure 1 , the ideal temperature range for the high - temperature performance improvement region is ≤136 °C and ≥153 °C. As can be seen from Figure 2 , the ideal temperature range to ensure that the warm mix synchronous recycled SBS modified asphalt does not crack at intermediate temperature is 119 - 155 °C. As can be seen from Figure 3 , the ideal temperature range for the low - temperature performance improvement region is 139 - 158 °C;

[0043] The above - mentioned warm mix as - received SBS modified asphalt is prepared by adding 3 wt% of Sasobit to the as - received SBS modified asphalt and rapidly stirring at 150 °C for 15 s;

[0044] (8) Take the intersection of the three ideal temperature ranges, as shown in Figure 4As shown, the optimal construction temperature range for warm mix synchronous regeneration of the waste SBS modified asphalt is 153 - 155°C. To achieve green and low-carbon construction, 153°C can be determined as the final optimal construction temperature.

[0045] To further quantitatively determine the dosage of Sasobit when the warm mix synchronous regeneration temperature can reach 153°C, Sasobit warm mix synchronous regeneration SBS modified asphalts with Sasobit dosages of 1.5wt%, 2.0wt%, 2.5wt%, 3.0wt% and 3.5wt% were prepared at 153°C. The dosages of aromatic oil and TAIC, and the stirring time were the same as those mentioned above. Referring to the Chinese standard "Test Procedures for Bitumen and Bituminous Mixtures for Highway Engineering" (JTG E20—2011), first, the Brookfield rotational viscosity of the original SBS modified asphalt was tested at 115 - 175°C, the viscosity-temperature scatter plot was drawn, and the viscosity-temperature curve fitting equation was obtained, as Figure 5 shown; subsequently, according to the construction temperature (mixing temperature) of the original SBS modified asphalt recommended by the "Technical Specification for Construction of Highway Asphalt Pavement" (JT F40—2004), that is, 177.5°C was substituted into the viscosity-temperature curve fitting equation, and the optimal construction target viscosity of the original SBS modified asphalt was solved to be 568.87 mPa·s; then, the Brookfield rotational viscosity of the Sasobit warm mix synchronous regeneration SBS modified asphalt was tested at 153°C, and the viscosity-Sasobit dosage scatter plot was also drawn to obtain the fitting equation, as Figure 6 shown; finally, the target viscosity of 568.87 mPa·s was substituted into the Figure 6 fitting equation, and the dosage of Sasobit required for the RTFO + 40h PAV aged SBS modified asphalt during warm mix synchronous regeneration could be quantitatively calculated to be 2.84%.

[0046] Example 2

[0047] The original SBS modified asphalt used in this example is the same as that in Example 1. The SBS modified RAP aged asphalt was extracted from the milled old materials of the upper surface layer of the Hubei Expressway. The extraction experiment referred to the Chinese standard "Test Procedures for Bitumen and Bituminous Mixtures for Highway Engineering" (JTG E20—2011). The aged matrix asphalt component conditioner and the broken SBS molecular chain linker used in this example are the same as those in Example 1. To reduce the hot mix regeneration construction temperature, the surfactant Evotherm 3G was selected as the warm mix agent.

[0048] (1) The SBS modified RAP aged asphalt was grouped, also divided into 9 groups, and used as samples for standby;

[0049] (2) Customize a two-component rejuvenator for SBS-modified RAP aged asphalt. Also referring to Chinese invention patent CN118069976A, the optimal dosages of aromatic oil and TAIC are determined to be 4.20 wt% and 4.82 wt%, respectively.

[0050] (3) Heat the SBS-modified RAP aged asphalt to melting at 115 - 195 °C, add 4.20 wt% of aromatic oil and 4.82 wt% of TAIC, stir rapidly for 75 s, then add 1 wt% of Evotherm 3G and stir rapidly again for 15 s to obtain the warm mix synchronous regeneration SBS-modified asphalt of the corresponding group. Place the prepared warm mix synchronous regeneration SBS-modified asphalt in an oven at 115 - 195 °C for heat preservation for 2 h to simulate the transportation, paving, and compaction processes of the actual warm mix synchronous regeneration SBS-modified asphalt mixture. Refer to the operations in steps (3) and (4) of Example 1, and keep the heat preservation temperature of each sample the same as its corresponding melting temperature before.

[0051] (4) Conduct multiple stress creep recovery tests, G-R parameter tests, and low-temperature shear creep recovery tests on the warm mix synchronous regeneration SBS-modified asphalt under different heat preservation conditions.

[0052] (5) According to the key evaluation indexes of the high-temperature, medium-temperature, and low-temperature rheological property test results, draw the scatter diagrams of the typical rheological property changes of the warm mix synchronous regeneration SBS-modified asphalt under different heat preservation conditions, and construct the corresponding fitting equations at the same time.

[0053] (6) Take the warm mix original SBS-modified asphalt J nr3.2 and 90% of the shear total strain as the high- and low-temperature rheological property thresholds of the warm mix synchronous regeneration SBS-modified asphalt, and take the G-R parameter equal to 180 kPa as the medium-temperature rheological property threshold of the warm mix synchronous regeneration SBS-modified asphalt. Determine that the ideal temperature range for the high-temperature performance improvement area is ≤134 °C and ≥157 °C, the ideal temperature range for the medium-temperature without cracking is 121 - 159 °C, and the ideal temperature range for the low-temperature performance improvement area is 136 - 161 °C.

[0054] The above warm mix original SBS-modified asphalt is prepared by adding 3 wt% of Evotherm 3G to the original SBS-modified asphalt and stirring rapidly at 150 °C for 15 s.

[0055] (7) Take the intersection of the three ideal temperature ranges. As Figure 7 shown, that is, 157 - 161 °C is the optimal construction temperature range for the warm mix synchronous regeneration of this waste SBS-modified asphalt. In order to achieve green and low-carbon construction, 157 °C can be determined as the final optimal construction temperature.

[0056] To further clarify the dosage of Evotherm 3G when the warm mix synchronous regeneration temperature can reach 157°C, Evotherm 3G warm mix synchronous regeneration SBS modified asphalt with dosages of 0.25wt%, 0.50wt%, 0.75wt%, 1.0wt% and 1.25wt% were prepared at 157°C. The Brookfield rotational viscosity of the Evotherm 3G warm mix synchronous regeneration SBS modified asphalt was tested at 157°C, and a scatter plot of viscosity - Evotherm 3G dosage was drawn to obtain a fitting equation, as Figure 8 shown. Substituting the target viscosity of 568.87 mPa·s into the Figure 8 fitting equation, the dosage of Evotherm 3G required for SBS modified RAP aged asphalt mixture during warm mix synchronous regeneration can be quantitatively calculated to be 0.85%.

[0057] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for determining the optimal construction temperature for warm mix synchronous regeneration of waste SBS modified asphalt, characterized in that: The following steps are involved: (1) Grouping the aged SBS modified asphalt for standby use; (2) heating each group of aged SBS modified asphalt to melt at different temperatures, adding an aged matrix asphalt component blending agent and a broken SBS molecular chain connector, stirring rapidly, adding a warm mix agent and stirring rapidly again, to obtain multiple groups of warm mix synchronously regenerated SBS modified asphalt; (3) Each group of warm-mixed synchronously recycled SBS modified asphalt was placed in an oven at different temperatures for 2 h to simulate the actual construction process; (4) Testing the typical rheological properties of warm-mixed synchronously recycled SBS modified asphalt under different insulation conditions, including high-temperature anti-rutting performance, medium-temperature anti-cracking performance, and low-temperature anti-fracture performance; (5) Draw a scatter plot of the typical rheological properties of warm-mixed synchronously recycled SBS modified asphalt under different insulation conditions, and construct the corresponding fitting equation; (6) Based on the threshold of the rheological properties of warm-mixed original SBS modified asphalt, three ideal temperature ranges corresponding to the high-temperature anti-rutting performance, medium-temperature anti-cracking performance, and low-temperature anti-fracture performance of warm-mixed synchronously recycled SBS modified asphalt are divided; (7) The intersection of the three ideal temperature ranges is the optimal construction temperature for warm mix synchronous regeneration of waste SBS modified asphalt.

2. The method for determining the optimal construction temperature for warm mix synchronous regeneration of waste SBS modified asphalt according to claim 1, characterized in that: In step (2), the aged base asphalt component blending agent is selected from waste engine oil, aromatic oil, naphthenic oil, petroleum wax oil, cottonseed oil, composite castor oil, mustard oil, soybean oil, tall oil, cashew nut shell oil and sunflower oil; The SBS molecular chain breaking connecting agent is one or more of epoxy compounds, isocyanate compounds and polymer prepolymers; The warm-mix agent is selected from organic wax warm-mix agents and surfactant warm-mix agents.

3. The method for determining the optimal construction temperature for warm mix synchronous regeneration of waste SBS modified asphalt according to claim 1, characterized in that: In step (2), the rapid stirring time after adding the aged matrix asphalt component blending agent and the broken SBS molecular chain connecting agent is 75 seconds; the rapid stirring time after adding the warm mixing agent is 15 seconds.

4. The method for determining the optimal construction temperature for warm mix synchronous regeneration of waste SBS modified asphalt according to claim 1, characterized in that: In step (2), the dosage of the aged base asphalt component blending agent is 4-7% of the mass of the aged SBS modified asphalt; the dosage of the broken SBS molecular chain connecting agent is 4-6% of the mass of the aged SBS modified asphalt; and the dosage of the warm mix agent is 1-3% of the mass of the aged SBS modified asphalt.

5. The method for determining the optimal construction temperature for warm mix synchronous regeneration of waste SBS modified asphalt according to claim 1, characterized in that: In steps (2) to (3), the different temperatures are controlled between 115 and 195°C, with a temperature gradient interval of 10°C; wherein the melting temperature of the aged SBS modified asphalt is the same as the insulation temperature of the corresponding warm mix synchronously regenerated SBS modified asphalt.

6. The method for determining the optimal construction temperature for warm mix synchronous regeneration of waste SBS modified asphalt according to claim 1, characterized in that: In step (6), the irrecoverable creep compliance and 90% of the total shear strain of the warm-mixed original SBS modified asphalt are used as the high and low temperature rheological property thresholds of the warm-mixed synchronously regenerated SBS modified asphalt, and the GR parameter equal to 180 kPa is used as the medium temperature rheological property threshold of the warm-mixed synchronously regenerated SBS modified asphalt.

7. The method for determining the optimal construction temperature for warm mix synchronous regeneration of waste SBS modified asphalt according to claim 1, characterized in that: In step (6), the warm mix original SBS modified asphalt is prepared by adding a warm mix agent to the original SBS modified asphalt and rapidly stirring at 150° C. for 15 seconds.

8. The method for determining the optimal construction temperature for warm mix synchronous regeneration of waste SBS modified asphalt according to claim 1, characterized in that: According to the determined optimal construction temperature, the viscosity-temperature curve of warm-mix synchronously recycled SBS modified asphalt at different dosages of warm-mix agent is tested and plotted. According to the optimal construction viscosity corresponding to the original SBS modified asphalt specified in the specification, the optimal dosage of the warm-mix agent is calculated in reverse.

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