High-petroleum-ratio thin overlay asphalt mixture as well as preparation method and construction method thereof

Abstract

The invention discloses a high-petroleum-ratio thin overlay asphalt mixture as well as a preparation method and a construction method thereof, and the asphalt-aggregate ratio of the high-petroleum-ratio thin overlay asphalt mixture is 6.3-6.4; the raw materials comprise warm-mixed high-viscosity asphalt, aggregate, mineral powder and polyester fibers; the warm-mixed high-viscosity asphalt comprises the following raw materials: 90-93% of modified asphalt, 3-5% of a linear SBS modifier and 3-5% of high-elastic asphalt. The modified asphalt is prepared by grafting a furan group on asphalt and then reacting with maleimide-terminated polyethylene glycol; the high-elastic asphalt is prepared from common asphalt and modified ZTS high-elastic particles; the aggregate comprises basalt of 3-5 mm, basalt of 5-10 mm and machine-made sand, and the mass ratio of the basalt of 3-5 mm to the basalt of 5-10 mm to the machine-made sand to the mineral powder is 50: (20-22): (21-23): (6-8); and the mass dosage of the polyester fibers is 0.2-0.4% of the mass of the warm-mixed high-viscosity asphalt. The method is not only suitable for pavements with better road conditions, but also suitable for pavements with poorer road conditions, especially suitable for cement concrete white-to-black and additionally paved asphalt surface layers, and the adaptability is improved.

Description

Technical Field

[0001] The present invention relates to a high asphalt ratio thin layer wearing asphalt mixture, a preparation method thereof and a construction method thereof, belonging to the technical field of high asphalt ratio thin layer wearing asphalt mixture. Background Art

[0002] At present, the asphalt surface wearing course in China generally adopts AC-13 or SMA-13 with a thickness of 4 cm, and there are mainly the following problems: a large amount of stone materials and asphalt are required; the construction energy consumption is high; the anti-skid attenuation is fast; the material utilization rate is low. At present, some thin layer wearing asphalt mixtures have also been developed in China. The thin layer wearing asphalt mixture is an asphalt pavement structural layer with a relatively thin thickness (usually 2.5 to 5 cm), which is mainly used for preventive maintenance of old roads or surface functional layers of newly built roads, and has the characteristics of fast construction, quick opening to traffic, low cost, environmental protection and high efficiency.

[0003] There are still a large number of cement concrete pavements (bridge decks) in China, and various problems (noise and flatness) and diseases exist during the use process. The "white to black" conversion by paving an asphalt layer on the cement pavement is a trend, which combines the excellent road performance of the asphalt pavement and the high structural strength of the old cement concrete pavement, and has been widely used in the improvement and transformation projects of old concrete pavements. Practice has shown that the "white to black" pavement with reasonable design and construction can overall improve the pavement use quality, improve the road traffic capacity and extend the pavement service life.

[0004] Reflective cracks are common diseases or potential risks in the asphalt layer paved on the cement pavement. The thinner the paving mixture thickness, the shorter the propagation path of the reflective cracks, and the easier it is to generate reflective cracks. Considering the need to delay or prevent reflective crack problems, it is necessary to thicken the wearing layer, increasing the cost. Moreover, the quality and performance of the existing thin layer wearing asphalt mixtures vary, and there is room for further improvement.

[0005] The present invention adopts a stable skeleton structure with high density, and realizes performance improvement through a high asphalt-aggregate ratio and asphalt modification. It is applicable not only to pavements with good road conditions, but also to pavements with poor road conditions, especially for the "white to black" conversion by paving an asphalt surface layer on the cement concrete pavement. Summary of the Invention

[0006] The present invention provides a high asphalt ratio thin layer wearing asphalt mixture, a preparation method thereof and a construction method thereof, which have high asphalt content and self-healing performance, and can well solve problems such as the easy occurrence of reflective cracks in the asphalt layer paved on the cement pavement, etc.

[0007] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0008] A high asphalt ratio thin layer wearing asphalt mixture has an asphalt-aggregate ratio of 6.3 to 6.4; its raw materials include warm mix high viscosity asphalt, aggregates, mineral powder and polyester fiber;

[0009] The raw materials of the warm mix high-viscosity asphalt include 90-93% of modified asphalt, 3-5% of linear SBS modifier, and 3-5% of high-elastic asphalt;

[0010] The modified asphalt is prepared by grafting furan groups onto asphalt and then reacting with maleimide-capped polyethylene glycol;

[0011] The high-elastic asphalt is prepared from ordinary asphalt and modified ZTS high-elastic particles;

[0012] The aggregates include 3-5mm basalt, 5-10mm basalt, and manufactured sand. The mass ratio of 3-5mm basalt, 5-10mm basalt, manufactured sand, and mineral powder is 50:(20-22):(21-23):(6-8); the mass dosage of polyester fiber is 0.2-0.4% of the mass of the warm mix high-viscosity asphalt.

[0013] The modified asphalt in the present invention contains furan-maleimide dynamic covalent bonds. Utilizing the compatibility of the aromatic ring structure in the asphalt matrix, furan groups are introduced by free radical grafting, and then cross-linked with maleimide to form a thermoreversible network. It has strong environmental adaptability and improved repair efficiency. The self-repair performance can be activated by the heat generated by vehicle loads, taking into account high-temperature stability (bonding is stable below 160°C) and low-temperature flexibility (bonding is not brittle at -20°C).

[0014] The above-mentioned aggregate design is unique and can form a dense skeleton structure. The above 3-5mm includes 3mm and does not include 5mm; 5-10mm includes 5mm and does not include 10mm.

[0015] Adding linear SBS modifier to the above warm mix high-viscosity asphalt can increase the softening point of the asphalt by 10-15°C, and the low-temperature ductility is increased to more than 20cm, achieving a balance between high-temperature stability (softening point) and low-temperature toughness (ductility). The dynamic stability can reach more than 8000 times / mm.

[0016] The synergistic enhancement effect between ZTS high-elastic particles and linear SBS modifier is obvious, which can promote the improvement of dynamic stability and the like.

[0017] The most important disease of the road surface is the generation of cracks. In this application, through high asphalt-aggregate ratio and asphalt modification, the mixture has a function of elastic recovery. After cracks occur, through vehicle loads, high asphalt-aggregate ratio, and self-repair function, it can heal quickly, making this application suitable not only for road surfaces with good road conditions but also for road surfaces with poor road conditions, especially for the white-to-black overlay of cement concrete pavement with asphalt surface layer.

[0018] In order to improve the road surface performance, in the above warm mix high-viscosity asphalt, 70# base asphalt is used for the modified asphalt; 90# base asphalt is used for the high-elastic asphalt.

[0019] The above-mentioned combined use of 70# base asphalt and 90# base asphalt promotes the improvement of high-temperature stability (dynamic stability at 60°C).

[0020] The preparation method of the above-mentioned modified asphalt includes the following steps:

[0021] Step 1: Asphalt pre-activation and furan group grafting (free radical copolymerization): React 70# base asphalt, furan acrylate, and benzoyl peroxide at a temperature of 130 - 140°C for 1 - 2 h, then cool to 70 - 80°C in an ice bath, add hydroquinone to terminate free radicals and prevent side reactions, and stir evenly to obtain furan group grafted asphalt.

[0022] Step 2: Prepare maleimide-capped polyethylene glycol: Dissolve polyethylene glycol in a phosphate buffer solution (PBS) with a pH of 7.0 - 7.4 to obtain a PBS solution of PEG; dissolve N-succinimidyl 4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC) in anhydrous dimethyl sulfoxide (DMSO) to obtain a DMSO solution of SMCC; stir at room temperature and slowly add (60 - 90 drops / min) the DMSO solution of SMCC to the PBS solution of PEG. After the addition, continue to stir and react for 2 - 3 hours. After the reaction, dialyze (using a dialysis bag with a molecular weight cut-off of 3500 Da) to remove unreacted SMCC and other small molecule impurities. The dialysis time is 24 - 48 hours, and the external dialysis solution is changed every 6 - 8 h. Finally, freeze-dry the dialyzed solution to obtain maleimide-capped polyethylene glycol.

[0023] Step 3: Heat the furan group grafted asphalt to 110 - 120°C, add maleimide-capped polyethylene glycol under shear at 3000 - 4000 rpm, and then react at 110 - 120°C for 20 - 30 min to obtain modified asphalt.

[0024] In the above Step 1, benzoyl peroxide decomposes under heat to generate benzoyloxy free radicals, which attack the aromatic ring α-H in the asphalt molecules to form asphalt free radicals; the asphalt free radicals add to the acrylate double bond of furan acrylate, and the furan ring is grafted through a carbon-carbon bond (the grafting rate is controlled at 3% - 5% to avoid over-crosslinking).

[0025] In Step 3, the furan ring and maleimide form a six-membered ring structure (mainly the endo product) through a cycloaddition reaction, which can achieve self-healing.

[0026] The above-mentioned use of the compatibility of the asphalt's own aromatic ring structure to construct non-polar dynamic bonds through the Diels-Alder reaction solves the problem of poor compatibility between the traditional system and the asphalt matrix.

[0027] To better ensure the modification effect, in the above step 1, the mass ratio of asphalt: furan acrylate: benzoyl peroxide: hydroquinone is 100: (3 - 5): (0.5 - 1.5): (0.2 - 0.5).

[0028] In the above step 2, the molecular weight of polyethylene glycol is 2000 - 8000 Da.

[0029] Unless otherwise specified, the molecular weight in this application is the weight - average molecular weight.

[0030] In the above step 2, the molar ratio of polyethylene glycol to succinimidyl 4 - (N - maleimidomethyl) cyclohexane - 1 - carboxylate is 1: (1.1 - 1.3).

[0031] In the above step 3, the mass ratio of furan - group - grafted asphalt to maleimide - terminated polyethylene glycol is 100: 2.5 - 3.5.

[0032] The preparation method of the above high - elastic asphalt includes the following steps:

[0033] 1) Place the ZTS high - elastic particles in an oven at 120 - 130 °C for preheating for 20 - 30 minutes to remove surface moisture and reduce viscosity, and add a silane coupling agent (such as KH - 560) at 0.3% - 0.5% of the mass of the ZTS high - elastic particles, and stir at 130 - 140 °C for 1 - 2 hours to enhance the interfacial adhesion with asphalt;

[0034] 2) Put the ZTS particles obtained in step 1 and 90# base asphalt into a planetary mixer in a ratio of (0.8 - 1.2):10, and use intermittent stirring at 130 - 140 °C for 8 - 12 min. Every 2 - 3 min of stirring, let it stand for 0.5 - 1 min to avoid local shear overheating, and obtain a premixed liquid;

[0035] 3) Transfer the premixed liquid to a colloid mill, and use gradient shearing at 130 - 140 °C for 20 - 30 min. The first 5 - 10 minutes are at 2000 - 3000 rpm, and the last 15 - 20 minutes are at 4000 - 5000 rpm to form a stable system with a concentrated particle size distribution, and then cool naturally to obtain high - elastic asphalt.

[0036] The above high - elastic asphalt can effectively improve the softening point, low - temperature ductility and dynamic stability, and at the same time reduce the construction temperature.

[0037] The preparation method of the above high - petroleum - ratio thin - layer wearing - course asphalt mixture includes the following steps:

[0038] 1) Add linear SBS modifier and high-elastic asphalt into the modified asphalt, shear at 3000 - 4000 rpm for 20 - 30 min, then keep the temperature at 140 - 150 °C, transfer it to the development tank for development for 1.5 - 2 h to obtain warm mix high-viscosity asphalt;

[0039] 2) Mix the aggregates evenly, heat them to 140 - 150 °C, then add the warm mix high-viscosity asphalt and polyester fiber and mix for 25 - 30 s, finally add mineral powder and mix for 10 - 15 s and then take out of the pot to obtain the thin-layer wearing surface asphalt mixture with high asphalt-aggregate ratio.

[0040] The construction method of the above thin-layer wearing surface asphalt mixture with high asphalt-aggregate ratio: After the ultra-thin wearing surface is discharged, it can be transported to the construction site for paving. The paving speed reaches 10 - 12 m / min, the initial compaction temperature is 120 - 130 °C, the final compaction temperature is not lower than 90 °C, the comprehensive compaction passes are 4 - 5 times, and the loose paving coefficient is between 1.05 - 1.1.

[0041] Technologies not mentioned in the present invention shall refer to the prior art.

[0042] The present invention has the following beneficial effects:

[0043] 1. By means of high asphalt-aggregate ratio and asphalt self-healing modification, the problem that reflection cracks are likely to occur in the reconstruction and overlay of cement concrete pavements with asphalt concrete is solved. Once reflection cracks occur, due to the characteristics of high asphalt content and self-healing, the cracks will also heal quickly. At the same time, a small amount of polyester fiber is added to increase the cohesion and shear strength of the asphalt concrete, further enhancing the anti-reflection crack ability of the concrete pavement.

[0044] 2. Existing thin-layer wearing surface asphalt mixtures are mostly applicable to sections with good road conditions such as expressways and national and provincial trunk lines. However, this application is not only applicable to pavements with good road conditions but also applicable to pavements with poor road conditions, especially the white-to-black overlay of cement concrete pavements with asphalt surface layer, improving the adaptability.

[0045] 3. The thickness of this application is 1.5 - 2.5 cm, which greatly saves costs compared with the conventional 4 cm asphalt concrete;

[0046] 4. The present invention adopts warm mix high-viscosity asphalt, which can reduce the mixing temperature from 175 °C to 140 - 150 °C.

[0047] 5. During the actual construction process of the present invention, the paving speed is as fast as 10 - 12 m / min, and only 4 - 5 passes of steel wheel rolling are required, without the need for rubber wheel roller compaction, saving machine and labor costs. Description of the Drawings

[0048] Figure 1 It is the transportation process diagram of the thin-layer wearing surface asphalt mixture with high asphalt-aggregate ratio during the experiment of the present invention;

[0049] Figure 2 This is the site map of tack coat spraying during the experiment of the present invention;

[0050] Figure 3 This is the site map of double-drum roller compaction during the experiment of the present invention;

[0051] Figure 4 This is the test map of wearing course thickness during the experiment of the present invention;

[0052] Figure 5 This is the detection map of pavement performance of thin layer wearing course during the experiment of the present invention; Detailed implementation manners

[0053] To better understand the present invention, the content of the present invention will be further clarified below in conjunction with embodiments. However, the content of the present invention is not limited to the following embodiments only.

[0054] In each example:

[0055] Unless otherwise specified, the temperature is carried out at room temperature (20 - 25 °C). Unless otherwise specified, the stirring speed is 300 rpm.

[0056] The pH of the phosphate buffer solution is 7.0, which is formed by mixing 0.2M NaH2PO4 aqueous solution and 0.2M Na2HPO4 aqueous solution with a volume ratio of 39:61. The polyester fiber is purchased from 2mm long polyester fiber produced by Anhui Zhongzhiyuan Engineering Technology Co., Ltd. The 70# and 90# matrix asphalt (ordinary asphalt) are produced by Nanjing Refinery Co., Ltd. The ZTS high elastic particles are purchased from Beijing Zhongtian Road Industry Technology Co., Ltd. The linear SBS modifier is purchased from Baling Petrochemical (China), with the product number YH-791.

[0057] Example 1

[0058] The preparation method of modified asphalt includes the following steps:

[0059] Step 1: React 70# matrix asphalt, tetrahydrofurfuryl acrylate and benzoyl peroxide with a mass ratio of 100:5:1 at a temperature of 140 °C for 2 h, then cool down to 80 °C in an ice bath, add hydroquinone with a mass dosage of 0.3% relative to the 70# matrix asphalt, and stir evenly to obtain furan group grafted asphalt;

[0060] Step 2: Dissolve polyethylene glycol 2000 in phosphate buffered saline PBS with a pH of 7.0 - 7.4 to obtain a PBS solution of PEG (the mass ratio of polyethylene glycol 2000 to phosphate buffered saline is 1:3); dissolve N-succinimidyl 4-(N-maleimidomethyl) cyclohexane-1-carboxylate SMCC in anhydrous dimethyl sulfoxide DMSO to obtain a DMSO solution of SMCC (the concentration of SMCC is 10 mg / mL); stir at room temperature and add the DMSO solution of SMCC dropwise to the PBS solution of PEG at a rate of 60 drops / min. After the addition is completed (the molar ratio of polyethylene glycol to N-succinimidyl 4-(N-maleimidomethyl) cyclohexane-1-carboxylate is 1:1.2), continue to stir and react for 2 hours. After the reaction is completed, dialyze for 48 hours using a dialysis bag with a molecular weight cut-off of 3500 Da, changing the external dialysis solution every 8 hours. Freeze-dry the dialyzed solution (-45°C pre-freezing for 3 hours, -20°C, 20 Pa sublimation drying for 8 hours, 25°C, 10 Pa desorption drying for 5 hours) to obtain maleimide-terminated polyethylene glycol.

[0061] Step 3: Heat the furan-group grafted asphalt to 120°C, add maleimide-terminated polyethylene glycol under shear at 3000 rpm (the mass ratio of furan-group grafted asphalt to maleimide-terminated polyethylene glycol is 100:3), and then react at 120°C for 30 minutes to obtain modified asphalt. Through infrared spectroscopy (FTIR) detection, the C=C double bond absorption peak at 1600 - 1500 cm-1 disappears, and a new absorption peak of the in-ring C-C bond at 1100 - 1200 cm-1 appears.

[0062] Example 2

[0063] The preparation method of high-elastic asphalt is as follows:

[0064] 1) Place the ZTS high-elastic particles in an oven at 130°C and preheat for 30 minutes to remove surface moisture and reduce viscosity. Add silane coupling agent KH-560 at 0.3% of the mass of the ZTS high-elastic particles and stir at 130°C for 2 hours to enhance the interfacial adhesion with asphalt, obtaining ZTS modified particles;

[0065] 2) Put the ZTS modified particles obtained in step 1) and 90# base asphalt into a planetary mixer at a ratio of 1:10, and stir intermittently at 130°C for 12 minutes. Let it stand for 1 minute every 3 minutes of stirring to avoid local shear overheating, obtaining a premixed liquid;

[0066] 3) Transfer the premixed liquid to a colloid mill and perform gradient shearing at 140°C for 30 min, with 3000 rpm in the first 10 minutes and 5000 rpm in the next 20 minutes, to form a stable system with a concentrated particle size distribution. Then cool it naturally to obtain highly elastic asphalt. The performance is shown in Table 1. Observed by a fluorescence microscope (400 times), the size of the ZTS aggregates < 50 μm.

[0067] Table 1

[0068]

[0069]

[0070] Example 3

[0071] A preparation method of a high petroleum ratio thin layer wearing asphalt mixture, comprising the following steps:

[0072] 1) Add a linear SBS modifier and highly elastic asphalt (prepared by referring to the method of Example 2) to the modified asphalt (prepared by referring to the method of Example 1), shear at 3000 rpm for 30 min, then keep the temperature at 145°C, and transfer it to a development tank for 2 h to obtain warm mix high viscosity asphalt. The mass ratio of the linear SBS modifier, highly elastic asphalt, and modified asphalt is 4:5:91;

[0073] 2) Mix the aggregates evenly, heat them to 145°C, then add the warm mix high viscosity asphalt and polyester fiber and mix for 30 s, and finally add mineral powder and mix for 15 s and then take out of the pot to obtain a high petroleum ratio thin layer wearing asphalt mixture. The aggregates include 3 - 5 mm basalt, 5 - 10 mm basalt, and manufactured sand. The mass ratio of 3 - 5 mm basalt, 5 - 10 mm basalt, manufactured sand (particle size ≤ 2.36 mm), and mineral powder (particle size ≤ 0.6 mm) is 50:21:22:7. The asphalt-aggregate ratio is 6.3 (the mass ratio of the warm mix high viscosity asphalt to the aggregates is 6.3), and the mass dosage of the polyester fiber is 0.3% of the mass of the warm mix high viscosity asphalt. The mineral powder is ground and processed from limestone.

[0074] The performance of the basalt aggregate is shown in Table 2.

[0075] Table 2

[0076] Test Items Unit Test Results Technical Requirements Test Methods Los Angeles Abrasion Loss ％ 4.6 ≤20 T 0317 Crushing Value ％ 10.4 ≤18 T 0316 Apparent Relative Density <![CDATA[g / cm 3 > 2.738 ≥2.7 T 0304 Adhesion to Asphalt Grade 5 ≥5 T 0616 Particles Smaller than 0.075mm ％ 0.7 ≤3 T 0310

[0077] The performance of the manufactured sand is shown in Table 3.

[0078] Table 3

[0079]

[0080]

[0081] The performance of the mineral powder is shown in Table 4.

[0082] Table 4

[0083]

[0084] In a mold of 50×50×5 mm, it is filled with a high petroleum ratio thin layer wearing course asphalt mixture, flattened, cooled to room temperature, a gap with a width of 2 mm, a length of 40 cm, and a depth of 5 mm is scratched on the surface, placed in an oven at 60 °C for 2 h, and then the gap disappears. The tensile strength recovery rate tested by a universal testing machine is ≥98.3%. It can achieve "self-activation" repair during the daily service temperature rise (the road surface temperature can reach 60 - 100 °C when the vehicle is driving), without the need for additional heating equipment.

[0085] Comparative Example 1

[0086] The difference from Example 3 is that the modified asphalt is replaced with unmodified 70# base asphalt, and the rest are all referred to Example 3. The obtained thin layer wearing course asphalt mixture has no self-healing performance.

[0087] Comparative Example 2

[0088] The difference from Example 3 is that the highly elastic asphalt is replaced with unmodified 90# base asphalt, and the rest are all referred to Example 3.

[0089] Comparative Example 3

[0090] The difference from Example 3 is that the linear SBS modifier is omitted, and the rest are all referred to Example 3.

[0091] Comparative Example 4

[0092] The difference from Example 3 is that the highly elastic asphalt is prepared with 70# base asphalt, and the rest are all referred to Example 3.

[0093] The Marshall tests of the high petroleum ratio thin layer wearing course asphalt mixture for each example are shown in Table 5.

[0094] Table 5

[0095]

[0096] Construction method:

[0097] After the high petroleum ratio thin layer wearing course asphalt mixture is discharged, it is transported to the construction site (as shown, the side of the transport vehicle is equipped with thermal insulation cotton, and the top of the mixture is covered with a cotton quilt). The original road surface at the construction site is a cement concrete road surface. An emulsified tack coat (Shell, model: NovaBond Figure 1 high viscosity modified emulsified asphalt, as shown in TM is sprayed on the cement concrete road surface to be constructed Figure 2As shown, the thin layer surface dressing has been constructed on one side, and the emulsified tack coat has been sprayed on the other side. The spraying amount of the tack coat is 0.21 kg / m 2 ; As Figure 3 shown, it is paved using a paver with a paving temperature of 140°C and a paving speed of 10 - 12 m / min. It is rolled 4 times with a 10-ton double-drum roller, the initial rolling temperature is 130°C, and the final rolling temperature is not lower than 90°C. The loose paving coefficient is between 1.05 and 1.1. As Figure 4 shown, the paving thickness of the surface dressing is tested to be 2.5 cm by core drilling and sampling.

[0098] As Figure 5 shown, the pavement performance of the thin layer surface dressing is tested, and the results are shown in Table 6.

[0099] Table 6

[0100] Test Items Test Results Index Requirements Flatness σ mm 0.6 ＜1.5 Skid Resistance Value BPN 70 ≥45 Texture Depth 1.0 ≥0.6 Permeability Coefficient (mL / min) 6 Measured

Claims

1. A thin-layer surface course asphalt mixture with a high asphalt ratio, characterized in that: The asphalt-aggregate ratio is 6.3 - 6.4; its raw materials include warm mix high-viscosity asphalt, aggregate, mineral powder, and polyester fiber; The raw materials of the warm mix high-viscosity asphalt include 90 - 93% of modified asphalt, 3 - 5% of linear SBS modifier, and 3 - 5% of high-elastic asphalt, and the aforementioned percentages are mass percentages; The modified asphalt is prepared by reacting asphalt grafted with furan groups with maleimide-capped polyethylene glycol; The high-elastic asphalt is prepared from ordinary asphalt and modified ZTS high-elastic particles; The aggregate includes 3 - 5 mm basalt, 5 - 10 mm basalt, and manufactured sand. The mass ratio of 3 - 5 mm basalt, 5 - 10 mm basalt, manufactured sand, and mineral powder is 50:(20 - 22):(21 - 23):(6 - 8); the mass dosage of polyester fiber is 0.2 - 0.4% of the mass of the warm mix high-viscosity asphalt.

2. The high petroleum ratio thin surface asphalt mixture according to claim 1, characterized in that: In the warm mix high-viscosity asphalt, 70# base asphalt is used for the modified asphalt; 90# base asphalt is used for the high-elastic asphalt.

3. The high petroleum ratio thin layer surface asphalt mixture according to claim 1 or 2, characterized in that: The preparation method of the modified asphalt includes the following steps: Step 1: React 70# base asphalt, furan acrylate, and benzoyl peroxide at a temperature of 130 - 140 °C for 1 - 2 h, then cool to 70 - 80 °C in an ice bath, add hydroquinone, and stir evenly to obtain furan-group grafted asphalt; Step 2: Dissolve polyethylene glycol in a phosphate buffer solution with a pH of 7.0 - 7.4 to obtain a PBS solution of PEG; Dissolve N-succinimidyl 4-(N-maleimidomethyl) cyclohexane-1-carboxylate in anhydrous dimethyl sulfoxide to obtain a DMSO solution of SMCC; stir at room temperature, slowly drip the DMSO solution of SMCC into the PBS solution of PEG. After the dripping is completed, continue to stir and react for 2 - 3 hours. After the reaction is completed, dialyze for 24 - 48 hours, and finally freeze-dry the dialyzed solution to obtain maleimide-capped polyethylene glycol. Step 3: Heat the furan-group grafted asphalt to 110 - 120 °C, add maleimide-capped polyethylene glycol under shear at 3000 - 4000 rpm, and then react at 110 - 120 °C for 20 - 30 min to obtain modified asphalt.

4. The high petroleum ratio thin layer surface asphalt mixture according to claim 3, characterized in that: In Step 1, the mass ratio of asphalt: furan acrylate: benzoyl peroxide: hydroquinone is 100:(3 - 5):(0.5 - 1.5):(0.2 - 0.5).

5. The high petroleum ratio thin layer surface dressing asphalt mixture according to claim 3, characterized in that: In Step 2, the molecular weight of polyethylene glycol is 2000 - 8000 Da.

6. The high petroleum ratio thin layer surface dressing asphalt mixture according to claim 3, characterized in that: In Step 2, the molar ratio of polyethylene glycol to N-succinimidyl 4-(N-maleimidomethyl) cyclohexane-1-carboxylate is 1:(1.1 - 1.3).

7. The high petroleum ratio thin layer surface asphalt mixture according to claim 3, characterized in that: In Step 3, the mass ratio of furan-group grafted asphalt to maleimide-capped polyethylene glycol is 100:(2.5 - 3.5).

8. The high petroleum ratio thin layer surface dressing asphalt mixture according to claim 1 or 2, characterized in that: The preparation method of the high-elastic asphalt includes the following steps: 1) Preheat the ZTS high-elastic particles in an oven at 120 - 130 °C for 20 - 30 minutes, and add a silane coupling agent at 0.3% - 0.5% of the mass of the ZTS high-elastic particles, and stir at 130 - 140 °C for 1 - 2 hours; 2) Put the ZTS particles obtained in step 1) and 90# matrix asphalt into a planetary mixer at a ratio of (0.8 - 1.2):10, and carry out intermittent stirring at 130 - 140 °C for 8 - 12 min. For every 2 - 3 min of stirring, let it stand for 0.5 - 1 min to obtain a premixed liquid; 3) Transfer the premixed liquid to a colloid mill, and carry out gradient shearing at 130 - 140 °C for 20 - 30 min. The speed is 2000 - 3000 rpm in the first 5 - 10 minutes and 4000 - 5000 rpm in the last 15 - 20 minutes to form a stable system with a concentrated particle size distribution, and then cool it naturally to obtain highly elastic asphalt.

9. A method for preparing a high petroleum ratio thin layer surface asphalt mixture according to any one of claims 1-8, characterized in that: The steps include: 1) Add linear SBS modifier and highly elastic asphalt to the modified asphalt, shear at 3000 - 4000 rpm for 20 - 30 min, then keep the temperature at 140 - 150 °C, transfer it to a development tank and develop for 1.5 - 2 h to obtain warm mix high-viscosity asphalt; 2) Mix the aggregates evenly, heat them to 140 - 150 °C, then add the warm mix high-viscosity asphalt and polyester fiber and mix for 25 - 30 s, and finally add mineral powder and mix for 1)0 - 15 s and then take out of the pot to obtain a high petroleum ratio thin layer wearing surface asphalt mixture.

10. Construction method of high petroleum ratio thin layer wearing asphalt mixture according to any one of claims 1-8: characterized in that: After the high petroleum ratio thin layer wearing surface asphalt mixture is discharged, it can be transported to the construction site for paving. The paving speed is 10 - 12 m / min, the initial compaction temperature is 120 - 130 °C, the final compaction temperature is not lower than 90 °C, the comprehensive compaction passes are 4 - 5 times, and the loose paving coefficient is between 1.05 - 1.1.

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