Graphene composite modified asphalt concrete material for ultra-thin surface dressing and preparation method thereof

Abstract

The application discloses a kind of graphene composite modified asphalt concrete materials for ultra-thin surface dressing and preparation method, belong to asphalt concrete technical field;Including 70-85 parts petroleum asphalt, 18-25 parts activated rubber powder, 1.5-2.5 parts SBS modifier, 0.15-0.25 parts stabilizer, 0.1-0.3 parts auxiliary agent, 0.5-1 parts PVDF, 0.5-1 parts modified basalt fiber, 0.6-1 parts graphene oxide powder and 0.3-1 parts ceramic powder;Preparation, first PVDF, modified basalt fiber, graphene oxide, ceramic powder and auxiliary agent are mixed, after being uniformly dispersed, petroleum asphalt and SBS modifier are added and fully stirred;Then the material is ground by high temperature and high pressure colloid, after being fully ground, activated rubber powder is added and ground again;Finally, add stabilizer to develop, after development is finished, graphene composite modified asphalt concrete material is prepared;The concrete material has super strong oil film bonding force, and excellent high-temperature stability, anti-variety, dynamic stability, can meet heavy load traffic requirements.

Description

Technical Field

[0001] This invention relates to the field of asphalt concrete preparation technology, and in particular to an ultra-thin graphene composite modified asphalt concrete material for overlay and its preparation method. Background Technology

[0002] Thin-layer overlay is a relatively new technology in preventive maintenance of road surfaces. It can be applied to both asphalt and cement pavements, demonstrating its versatility. Typical thin-layer overlays are only 20mm to 25mm thick and offer numerous advantages, including noise reduction, skid resistance, rapid drainage, convenient construction, low cost, and quick reopening to traffic. While improving driving comfort and safety, thin-layer overlays also achieve energy conservation, emission reduction, and low-carbon environmental protection during construction, and are gradually developing into a promising form of high-grade highway maintenance.

[0003] Currently, ultra-thin overlay asphalt concrete is mostly produced by mixing SBS modified asphalt, which can meet the performance requirements of medium and light transportation. However, relying solely on SBS modified asphalt materials is difficult to meet the requirements of heavy-duty transportation for resistance to deformation and dynamic stability. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a graphene composite modified asphalt concrete material for ultra-thin overlay and its preparation method. This concrete material has super strong oil film adhesion, excellent high temperature stability, high and low temperature resistance to deformation and dynamic stability, and can meet the requirements of heavy traffic.

[0005] The technical objective of this invention is achieved through the following technical solution:

[0006] A graphene-modified asphalt concrete material for ultrathin overlays, comprising the following components in parts by weight:

[0007] 70-85 parts petroleum asphalt, 18-25 parts activated rubber powder, 1.5-2.5 parts SBS modifier, 0.15-0.25 parts stabilizer, 0.1-0.3 parts additives, 0.5-1 parts PVDF, 0.5-1 parts modified basalt fiber, 0.6-1 parts graphene oxide powder, and 0.3-1 parts ceramic powder.

[0008] As some possible embodiments of this application, the concrete material comprises the following components in parts by weight:

[0009] 73-83 parts petroleum asphalt, 20-23 parts activated rubber powder, 1.8-2.3 parts SBS modifier, 0.18-0.2 parts stabilizer, 0.15-0.25 parts additives, 0.6-0.9 parts PVDF, 0.6-0.8 parts modified basalt fiber, 0.7-0.9 parts graphene oxide powder, and 0.4-0.8 parts ceramic powder.

[0010] As some possible embodiments of this application, the concrete material comprises the following components in parts by weight:

[0011] 80 parts petroleum asphalt, 20 parts activated rubber powder, 2 parts SBS modifier, 0.18 parts stabilizer, 0.2 parts additives, 0.9 parts PVDF, 0.8 parts modified basalt fiber, 0.8 parts graphene oxide powder and 0.7 parts ceramic powder.

[0012] As some possible embodiments of this application, the ceramic powder is selected from zirconium oxide, aluminum oxide, magnesium oxide, silicon carbide, silicon nitride, and boron nitride; the particle size of the ceramic powder is 50-500 nm.

[0013] As one possible implementation of this application, the ceramic powder is subjected to low-temperature plasma modification treatment.

[0014] As some possible embodiments of this application, the stabilizer is sulfur; the additive is rubber oil; and the petroleum asphalt is No. 70.

[0015] Furthermore, to achieve the above objectives, this application also provides a method for preparing an ultrathin graphene composite modified asphalt concrete material for overlay, comprising the following steps:

[0016] S1 Premixing: First, premix PVDF, modified basalt fiber, graphene oxide, ceramic powder and additives are mixed and dispersed evenly. Then, petroleum asphalt and SBS modifier are added and stirred thoroughly.

[0017] S2 Over-grinding and shearing: The material that was thoroughly stirred in step S1 is subjected to high temperature and high pressure colloid over-grinding. After thorough over-grinding, activated rubber powder is added and over-grinding is performed again.

[0018] S3 Development: A stabilizer is added to the material after grinding in step S2 to carry out development. After development, graphene composite modified asphalt concrete material is obtained.

[0019] As some possible implementation methods of this application, the grinding shearing time is 15-30 min, the grinding temperature is 180-200℃, and the grinding pressure is above 5 atmospheres.

[0020] As one possible implementation method of this application, the development temperature is 180-190°C.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] This application describes a concrete material prepared by compounding petroleum asphalt, activated rubber powder, SBS modifier, stabilizer, additives, PVDF, modified basalt fiber, graphene oxide powder, and ceramic powder. The material exhibits superior oil film adhesion, excellent high-temperature stability, resistance to deformation, and dynamic stability. Specifically, the concrete material has an oil film thickness ≥12.8 μm, a dynamic stability of not less than 7235 cycles / mm, and a low-temperature crack resistance of not less than 3301 με, demonstrating significant high-temperature stability and low-temperature crack resistance, thus meeting the requirements of heavy-duty traffic. Detailed Implementation

[0023] Currently, ultra-thin overlay asphalt concrete is mostly produced by mixing SBS modified asphalt, which can meet the maintenance requirements of medium and light transportation. However, relying solely on SBS modified asphalt materials is difficult to meet the requirements of heavy-duty transportation for high-temperature stability, resistance to deformation, and dynamic stability.

[0024] Based on this, this application provides an ultrathin graphene composite modified asphalt concrete material for overlay, comprising the following components by weight:

[0025] 70-85 parts petroleum asphalt, 18-25 parts activated rubber powder, 1.5-2.5 parts SBS modifier, 0.15-0.25 parts stabilizer, 0.1-0.3 parts additives, 0.5-1 parts PVDF, 0.5-1 parts modified basalt fiber, 0.6-1 parts graphene oxide powder, and 0.3-1 parts ceramic powder;

[0026] Among the above components, SBS modifier is widely used in asphalt modification due to its good low-temperature resistance, air permeability, and anti-skid properties. The dynamic stability of the base concrete system modified by SBS is mostly less than 2500 cycles / mm, and the low-temperature crack resistance is less than 1800με, which is difficult to meet the requirements of current heavy traffic for high-temperature stability, anti-deformation, and dynamic stability. In addition, the added SBS modifier and asphalt have significant differences in chemical structure and relative molecular mass, so their actual compatibility is poor, and they are prone to two-phase separation at high temperatures.

[0027] Based on this, this application adds modified basalt fiber and PVDF to the aforementioned basic concrete system. Modified basalt fiber, as a reinforcing material, can penetrate and fill the matrix, acting as a skeleton and effectively improving the mechanical strength and toughness of the concrete system, as well as preventing the formation of microcracks. PVDF possesses extremely strong high and low temperature resistance, wear resistance, high mechanical strength, and toughness. The addition of both significantly increases dynamic stability and crack resistance, thereby effectively improving the high-temperature stability, deformation resistance, and dynamic stability of the concrete system. Although the addition of modified basalt fiber and PVDF can improve the system's compatibility to some extent, the improvement in strength is limited and difficult to meet actual needs. Furthermore, cracking still occurs after a period of heavy traffic use, severely affecting road surface conditions and failing to meet the performance requirements of heavy traffic.

[0028] Based on this, this application adds graphene oxide to the above-mentioned components. Graphene oxide has anisotropic properties and can form a stable cross-linked network structure in the asphalt system. At the same time, it can be embedded in the concrete system to act as a skeleton, improving the dynamic stability and low-temperature crack resistance of the concrete system. In addition, the large number of active oxygen-containing functional groups such as hydroxyl, epoxy, and carboxyl groups contained in graphene oxide can form hydrogen bonds with modified basalt fibers and PVDF, thereby further improving the bonding force and compatibility of the components in the concrete system.

[0029] However, the addition of the above components increases the overall viscosity of the concrete system, leading to a relatively high discharge temperature. The ultra-thin overlay, due to its thinness and the high thermal conductivity of graphene oxide between components, experiences rapid cooling. This results in high requirements for construction, paving, and compaction, and is prone to technical problems such as low overlay structural strength, severe water seepage, and poor performance due to insufficient compaction. Modified basalt fiber is a good thermal insulation material that can slow down the cooling rate; however, its addition is limited, resulting in a limited insulation effect. Therefore, it is necessary to add other thermal insulation materials to further improve the overall thermal insulation effect of the asphalt system. Based on this, this application further adds nano-ceramic powder to the above components. This, in conjunction with the modified basalt fiber, can significantly improve the thermal insulation performance of petroleum asphalt, effectively avoiding technical problems such as low overlay structural strength and water seepage caused by insufficient compaction during actual paving due to the rapid cooling rate of the concrete system. Furthermore, the added nano-ceramic powder can further improve the high-temperature stability and low-temperature crack resistance of the concrete.

[0030] Through the synergistic effect of the above components, the prepared concrete material can have excellent high-temperature stability, resistance to deformation, and dynamic stability, meeting the performance requirements of heavy-duty transportation.

[0031] To further improve the high-temperature stability, deformation resistance, and dynamic stability of concrete materials, as some possible embodiments of this application, the amount of each component in the concrete material is further limited, namely, the concrete material comprises the following components by weight:

[0032] 73-83 parts petroleum asphalt, 20-23 parts activated rubber powder, 1.8-2.3 parts SBS modifier, 0.18-0.2 parts stabilizer, 0.15-0.25 parts additives, 0.6-0.9 parts PVDF, 0.6-0.8 parts modified basalt fiber, 0.7-0.9 parts graphene oxide powder, and 0.4-0.8 parts ceramic powder.

[0033] To further improve the high-temperature stability, deformation resistance, and dynamic stability of concrete materials, as some possible embodiments of this application, the amount of each component in the concrete material is further limited, namely, the concrete material comprises the following components by weight:

[0034] 80 parts petroleum asphalt, 20 parts activated rubber powder, 2 parts SBS modifier, 0.18 parts stabilizer, 0.2 parts additives, 0.9 parts PVDF, 0.8 parts modified basalt fiber, 0.8 parts graphene oxide powder and 0.7 parts ceramic powder.

[0035] In order to further improve the high-temperature stability, anti-deformation properties, and dynamic stability of concrete materials, as some possible embodiments of this application, the amount of each component in the concrete material is further limited, namely, the ceramic powder is selected from zirconium oxide, alumina, magnesium oxide, silicon carbide, silicon nitride, and boron nitride; the particle size of the ceramic powder is 50-500 nm.

[0036] To effectively improve the dispersion of ceramic powder, as one of the embodiments of this application, the ceramic powder is further processed, namely, it undergoes low-temperature plasma modification treatment. In this scheme, the surface of the ceramic powder is modified by low-temperature plasma irradiation technology, which enables the ceramic powder to exhibit good dispersion in the concrete material and improves its bonding with other components. Specifically, the plasma treatment method is as follows: the ceramic powder is placed in the vacuum reaction vessel of the low-temperature plasma treatment equipment, the gas pressure is evacuated to 5 Pa, then oxygen is introduced, and the vacuum valve is adjusted to maintain the vacuum degree at 80 Pa; then the radio frequency power supply is turned on, and the radio frequency power is adjusted to 320 watts to ionize the gas in the reaction vessel and generate glow discharge.

[0037] In order to further improve the high-temperature stability, anti-deformation properties, and dynamic stability of concrete materials, as some possible embodiments of this application, the types of stabilizers, additives, and petroleum asphalt in the concrete materials are further limited, namely, the stabilizer is sulfur; the additive is rubber oil; and the petroleum asphalt is No. 70.

[0038] Furthermore, to achieve the above objectives, this application also provides a method for preparing an ultrathin graphene composite modified asphalt concrete material for overlay, comprising the following steps:

[0039] S1 Premixing: Premixing: First, mix PVDF, modified basalt fiber, graphene oxide, ceramic powder and additives, disperse evenly, then add petroleum asphalt and SBS modifier and mix thoroughly.

[0040] S2 Over-grinding and shearing: The material that was thoroughly stirred in step S1 is subjected to high temperature and high pressure colloid over-grinding. After thorough over-grinding, activated rubber powder is added and over-grinding is performed again.

[0041] S3 Development: A stabilizer is added to the material after grinding in step S2 to carry out development. After development, graphene composite modified asphalt concrete material is obtained.

[0042] The preparation process of concrete materials includes three parts: premixing, shearing, and development. In the premixing stage, PVDF, modified basalt fiber, graphene oxide, ceramic powder, and additives are first premixed and stirred to achieve the purpose of dispersing PVDF, modified basalt fiber, graphene oxide, and ceramic powder in the additives. Then, petroleum asphalt and SBS modifier are added and stirred to achieve the dispersion of PVDF, modified basalt fiber, graphene oxide, and ceramic powder in the asphalt. Finally, after grinding and development, concrete materials are obtained. The entire preparation process is simple and suitable for industrial production.

[0043] As some possible implementation methods of this application, the grinding shearing time is 15-30 min, the grinding temperature is 180-200℃, and the grinding pressure is above 5 atmospheres.

[0044] As one possible implementation method of this application, the development temperature is 180-190℃. During the preparation of asphalt concrete, clumping was found. The reason for this was that the graphene composite modified asphalt had a high viscosity, the asphalt heating temperature was too low, and there was a lot of mineral powder adhering locally, resulting in clumping. By controlling the asphalt heating temperature at 180-190℃, the clumping phenomenon disappeared, and the mixture was evenly mixed and clear.

[0045] The specific preparation of the concrete material described in this application will be further described in detail below with reference to specific embodiments.

[0046] Example 1

[0047] S1 Premixing: First, mix 0.5 parts PVDF, 0.5 parts modified basalt fiber (basalt fiber modified with alkyl coupling agent KH550), 0.8 parts graphene oxide powder, and 0.7 parts alumina powder with 0.3 parts rubber oil until evenly dispersed. Then, add 80 parts No. 70 petroleum asphalt and 2 parts SBS modifier and mix thoroughly.

[0048] S2 Over-grinding and shearing: The material thoroughly stirred in step S1 is subjected to high-temperature and high-pressure colloid over-grinding. The over-grinding and shearing time is 15 minutes, the over-grinding temperature is 180-200℃, and the over-grinding pressure is above 5 atmospheres. After the over-grinding is complete, 21 parts of activated rubber powder are added and the material is over-grinded again for 15 minutes.

[0049] S3 Development: Add 0.2 parts of sulfur to the material after grinding in step S2 for development. The development temperature is 180-190℃ and the development time is 6h. After development, graphene composite modified asphalt concrete material is obtained.

[0050] The main properties of the prepared concrete material are: oil film thickness ≥12.8μm, dynamic stability 7235 cycles / mm, and low-temperature crack resistance 3301με.

[0051] Example 2

[0052] S1 Premixing: First, thoroughly mix 0.8 parts PVDF, 0.6 parts modified basalt fiber (basalt fiber modified with alkyl coupling agent KH550), 0.7 parts graphene oxide powder, and 0.8 parts alumina powder with 0.25 parts rubber oil until evenly dispersed. Then, add 81 parts No. 70 petroleum asphalt and 2.1 parts SBS modifier and mix thoroughly.

[0053] S2 Over-grinding and shearing: The material thoroughly stirred in step S1 is subjected to high temperature and high pressure colloid over-grinding. The over-grinding and shearing time is 15 minutes, the over-grinding temperature is 180-200℃, and the over-grinding pressure is above 5 atmospheres. After the over-grinding is complete, 20 parts of activated rubber powder are added and the material is over-grinded again for 15 minutes.

[0054] S3 Development: Add 0.18% sulfur to the material after grinding in step S2 for development. The development temperature is 180-190℃ and the development time is 6 hours. After development, graphene composite modified asphalt concrete material is obtained.

[0055] The main properties of the prepared concrete material are: oil film thickness ≥12.8μm, dynamic stability of 7257 cycles / mm, and low-temperature crack resistance of 3312με.

[0056] Example 3

[0057] S1 Premixing: First, thoroughly mix 0.9 parts PVDF, 0.8 parts modified basalt fiber (basalt fiber modified with alkyl coupling agent KH550), 0.8 parts graphene oxide powder, 0.7 parts alumina powder and 0.2 parts rubber oil. After dispersing evenly, add 80 parts No. 70 petroleum asphalt and 2 parts SBS modifier and mix thoroughly.

[0058] S2 Over-grinding and shearing: The material thoroughly stirred in step S1 is subjected to high temperature and high pressure colloid over-grinding. The over-grinding and shearing time is 15 minutes, the over-grinding temperature is 180-200℃, and the over-grinding pressure is above 5 atmospheres. After the over-grinding is complete, 20 parts of activated rubber powder are added and the material is over-grinded again for 15 minutes.

[0059] S3 Development: Add 0.18 parts of sulfur to the material after grinding in step S2 for development. The development temperature is 180-190℃ and the development time is 6h. After development, graphene composite modified asphalt concrete material is obtained.

[0060] The main properties of the prepared concrete material are: oil film thickness ≥12.8μm, dynamic stability 7280 cycles / mm, and low-temperature crack resistance 3320με.

[0061] Comparative Example 1 (without graphene oxide)

[0062] Compared to Example 3, the graphene oxide was replaced with modified basalt fiber, while the other components, amounts, and preparation methods remained unchanged.

[0063] The main properties of the prepared concrete material are: oil film ≤9μm, dynamic stability 4981 cycles / mm, and low-temperature crack resistance 2385με.

[0064] Comparative Example 2 (without modified basalt fiber and PVD)

[0065] Compared to Example 3, the modified basalt fiber and PVDF were replaced with graphene oxide, while the other components, amounts, and preparation methods remained unchanged.

[0066] The main properties of the prepared concrete material are: oil film ≤9μm, dynamic stability 5133 cycles / mm, and low-temperature crack resistance 2407με.

[0067] As can be seen from the performance of the concrete materials in Examples 1-3 and Comparative Examples 1-2, the concrete materials in Examples 1-3 were prepared strictly in accordance with the components, dosages and processes provided in this application. Their oil film thickness was ≥12.8μm, dynamic stability was not less than 7235 cycles / mm, and low-temperature crack resistance was not less than 3301με, showing significant high-temperature stability and low-temperature crack resistance.

[0068] In Comparative Example 1, without the addition of graphene oxide, the oil film thickness, dynamic stability, and low-temperature crack resistance were all worse than those in Examples 1-3. Even with the increased amount of modified basalt fiber, the performance remained low. This shows that simply relying on the amount of added components is not enough to effectively improve the performance of concrete materials.

[0069] In Comparative Example 2, which did not contain modified basalt fiber and PVDF, the oil film thickness, dynamic stability, and low-temperature crack resistance were all worse than those in Examples 1-3. Even with the increased amount of graphene oxide, the performance was still low. This shows that simply relying on the amount of added components is not enough to effectively improve the performance of concrete materials.

Claims

1. A graphene-modified asphalt concrete material for ultra-thin overlay, characterized in that, Includes the following components by weight: 70-85 parts petroleum asphalt, 18-25 parts activated rubber powder, 1.5-2.5 parts SBS modifier, 0.15-0.25 parts stabilizer, 0.1-0.3 parts additives, 0.5-1 parts PVDF, 0.5-1 parts modified basalt fiber, 0.6-1 parts graphene oxide powder, and 0.3-1 parts ceramic powder; The stabilizer is sulfur; the additive is rubber oil; The modified basalt fiber is basalt fiber modified with alkyl coupling agent KH550.

2. The graphene composite modified asphalt concrete material for ultra-thin overlay as described in claim 1, characterized in that, Includes the following components by weight: 73-83 parts petroleum asphalt, 20-23 parts activated rubber powder, 1.8-2.3 parts SBS modifier, 0.18-0.2 parts stabilizer, 0.15-0.25 parts additives, 0.6-0.9 parts PVDF, 0.6-0.8 parts modified basalt fiber, 0.7-0.9 parts graphene oxide powder, and 0.4-0.8 parts ceramic powder.

3. The graphene composite modified asphalt concrete material for ultra-thin overlay as described in claim 1, characterized in that, Includes the following components by weight: 80 parts petroleum asphalt, 20 parts activated rubber powder, 2 parts SBS modifier, 0.18 parts stabilizer, 0.2 parts additives, 0.9 parts PVDF, 0.8 parts modified basalt fiber, 0.8 parts graphene oxide powder and 0.7 parts ceramic powder.

4. The graphene composite modified asphalt concrete material for ultra-thin overlay as described in claim 1, characterized in that, The ceramic powder is selected from zirconium oxide, aluminum oxide, magnesium oxide, silicon carbide, silicon nitride, and boron nitride; the particle size of the ceramic powder is 50-500 nm.

5. The graphene composite modified asphalt concrete material for ultra-thin overlay as described in claim 1, characterized in that, The ceramic powder undergoes low-temperature plasma modification treatment.

6. The graphene composite modified asphalt concrete material for ultra-thin overlay as described in claim 1, characterized in that, The petroleum asphalt is No.

70.

7. A method for preparing an ultrathin graphene composite modified asphalt concrete material for overlay according to any one of claims 1-6, characterized in that, Includes the following steps: S1 Premixing: First, mix PVDF, modified basalt fiber, graphene oxide, ceramic powder and additives, disperse evenly, then add petroleum asphalt and SBS modifier and mix thoroughly. S2 Over-grinding and shearing: The material that was thoroughly stirred in step S1 is subjected to high temperature and high pressure colloid over-grinding. After thorough over-grinding, activated rubber powder is added and over-grinding is performed again. S3 Development: A stabilizer is added to the material after grinding in step S2 to carry out development. After development, graphene composite modified asphalt concrete material is obtained.

8. The method for preparing an ultrathin graphene composite modified asphalt concrete material for overlay as described in claim 7, characterized in that, The grinding and shearing time is 15-30 minutes, the grinding temperature is 180-200℃, and the grinding pressure is above 5 atmospheres.

9. The method for preparing an ultrathin graphene composite modified asphalt concrete material for overlay as described in claim 7, characterized in that, The optimal temperature for development is 180-190℃.