High-conductivity and high-frost-resistance concrete applied to traffic pavement in severe cold area and preparation method of high-conductivity and high-frost-resistance concrete
By incorporating reduced graphene oxide, steel fiber, and carbon fiber into concrete, highly conductive and frost-resistant concrete was prepared, solving the problem of poor frost resistance and durability of conductive concrete pavements in frigid regions. This enabled long-term service and efficient snow melting and de-icing effects in frigid areas.
Patent Information
- Application Number
- CN202511346619.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-19
- Publication Date
- 2025-12-16
AI Technical Summary
Existing conductive concrete pavements have poor freeze-thaw resistance and durability during service in extremely cold regions, leading to performance failure and failing to meet service life requirements.
Concrete with composite conductive phase materials, including reduced graphene oxide, steel fiber, and carbon fiber, is prepared through specific proportions and processes to create highly conductive and frost-resistant concrete. This process forms three-dimensional electron transport channels and improves the microstructure, thereby enhancing conductivity and frost resistance.
It improves the electrical conductivity and frost resistance of concrete, enabling it to serve for a long time in frigid regions, meeting service life requirements, and reducing maintenance costs and environmental pollution.
Smart Images
Figure CN121135286A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of building materials technology, and in particular to a high-conductivity, high-freeze-resistant concrete for use on traffic roads in frigid regions and its preparation method. Background Technology
[0002] Frequent snow and ice events in frigid regions lead to severe snow accumulation on roads, disrupting the daily lives of local residents. Traditional snow removal methods, such as manual snow removal combined with mechanical methods and de-icing agents, are inefficient, costly to maintain, and highly polluting. Conductive concrete active pavement heating technology, with its advantages of high efficiency, low maintenance costs, and virtually no environmental pollution, significantly improves the efficiency of snow and ice removal on roads.
[0003] Current research on active heating technology for conductive concrete pavements mainly focuses on improving snow and ice melting efficiency, i.e., improving the conductivity of concrete. However, conductive concrete pavements are primarily used in frigid regions where snow and ice events are frequent, and they are inevitably affected by freeze-thaw cycles during service, resulting in poor freeze-thaw durability and performance failure. Summary of the Invention
[0004] The technical problem to be solved by this invention is to overcome the shortcomings of the prior art and provide a highly conductive and highly frost-resistant concrete for road surfaces in extremely cold regions, as well as its preparation method. The concrete obtained by this invention is a concrete with a composite conductive phase material, possessing both high conductivity and good frost resistance, enabling it to adapt to the environment of extremely cold regions and meet the service life requirements of these regions.
[0005] The technical solution adopted by this invention to solve its technical problem is:
[0006] A method for preparing highly conductive and frost-resistant concrete for road surfaces in frigid regions includes the following steps:
[0007] Step S1: Weigh the following raw materials in parts by weight: 20-970 parts, fine aggregate 720-760 parts, cement 480-510 parts, water 225-240 parts, water-reducing agent 3.2-4.0 parts, carbon fiber 8.0-12.5 parts, steel fiber 70-85 parts, reduced graphene oxide 0.30-0.59 parts, dispersant 0.30-1.18 parts, and defoamer 0.20-0.40 parts.
[0008] Step S2: Prepare a reduced graphene oxide dispersion;
[0009] Step S3: Add coarse aggregate, fine aggregate and steel fiber to the concrete mixer and mix for 45-75 seconds until the steel fiber is evenly dispersed to obtain the mixture;
[0010] Step S4: Add cement and 50% of the reduced graphene oxide dispersion prepared in step S2 to the mixture obtained in step S3, stir for 45-75 seconds to obtain the composite cementitious material.
[0011] Step S5: Add water-reducing agent and the remaining 50% of reduced graphene oxide dispersion to the composite cementitious material obtained in step S4, stir for 45-75s, slowly add carbon fiber during the process, and continue stirring for 45-75s to obtain the mixture.
[0012] Step S6: Pour the mixture obtained in step S5 into a mold for sample preparation, place it on a vibration table to vibrate and compact it, let it stand for 20-24 hours, then demold it and place it in a standard curing chamber for curing until the specified age.
[0013] Furthermore, the fine aggregate is natural river sand with a particle size ≤ 4.75 mm, a water absorption rate of 0.2%, and an apparent density of 2620 kg / m³. 3 Fineness modulus 2.5.
[0014] Furthermore, the steel fiber is copper-plated steel fiber, with a fiber length of 13 mm, a single filament diameter of 200 μm, and a density of 7.8 g / cm³. 3 Tensile strength 2.85 GPa, volume resistivity 1.5 × 10⁻⁶ -5 With an Ω·cm ratio of 65 and a volumetric content of 1.0% vol, steel fibers not only improve the mechanical properties of concrete but also enhance its electrical conductivity.
[0015] Furthermore, the cement is P·O 42.5 ordinary Portland cement with an apparent density of 2963 kg / m³. 3 Specific surface area 350kg / m² 2 .
[0016] Furthermore, the water-reducing agent is a polycarboxylate high-performance water-reducing agent with a water reduction rate of 25%, a chloride ion content of 0.03%, an air content of 2.2%, a bleeding rate of 35%, a solid content of 39.8%, and a pH value of 6.25.
[0017] Furthermore, the carbon fiber is PAN-based carbon fiber, with a fiber length of 6 mm, a single filament diameter of 7.0–10 μm, a carbon content of ≥95%, and a density of 1.7 g / cm³. 3 Tensile strength 3.6–3.8 MPa, tensile modulus 220 GPa, volume resistivity 1.5 × 10⁻⁶ -3 The carbon fiber has an Ω·cm, an aspect ratio of 600–857, and a volumetric content of 0.6% vol. It uses PAN-based carbon fiber, which possesses excellent toughness, effectively preventing the formation of micro-cracks within concrete and improving its mechanical properties.
[0018] Furthermore, the reduced graphene oxide is a multilayer reduced graphene oxide with a diameter of 10–50 μm, a thickness of 3.4–7.0 nm, 6–10 layers, a monolayer ratio of 30%, a purity >95 wt%, and a specific surface area of 450–550 m². 2 / g.
[0019] Further, the dispersant is an anionic surfactant sodium dodecylbenzenesulfonate, with a moisture content ≤3.0%, active ingredient 30-40%, unsaponifiable matter content ≤3.0%, sodium sulfate content ≤9.0%, pH value 7.5-8.5, and content 88%;
[0020] The defoamer is tributyl phosphate, with a density of 0.974–0.980 g·ml, ≤0.002 mmol / g, moisture content ≤0.1%, and content ≥98.5%.
[0021] The water used is tap water.
[0022] Due to its π-packing (also known as π-π packing), reduced graphene oxide exhibits an inherent tendency to agglomerate, and the van der Waals forces between the thin sheets of reduced graphene oxide become the main factor hindering its uniform dispersion in cement-based composites. To ensure uniform dispersion of reduced graphene oxide during preparation, it needs to undergo dispersion treatment. Therefore, step S2, preparing a reduced graphene oxide dispersion, specifically includes the following steps:
[0023] Step S21: Add reduced graphene oxide, water, defoamer, and dispersant to a container to obtain a mixture;
[0024] Step S22: Use a magnetic stirrer to stir the mixture at a speed of 250 rad / min for 5 minutes. After the mixture is evenly dispersed and there is no obvious foam, pour it into multiple 50 ml centrifuge tubes.
[0025] Step S23: Set the temperature of the ultrasonic disperser to 50℃ and the frequency to 40kHz, and place multiple centrifuge tubes in the ultrasonic disperser to continue dispersing for 30 minutes.
[0026] Step S24: Remove the centrifuge tube and place it in tap water to cool to room temperature to obtain a reduced graphene oxide dispersion.
[0027] The reduced graphene oxide dispersion prepared by the above method needs to be used within 5 hours after cooling to room temperature to prevent the reduced graphene oxide in the dispersion from agglomerating and precipitating over time.
[0028] A highly conductive and frost-resistant concrete for use on traffic roads in frigid regions is prepared using the above-mentioned method.
[0029] The beneficial effects of this invention are: the invention is rationally designed and the preparation method is simple. Attached Figure Description
[0030] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0031] Figure 1 This is a flowchart of the preparation method in Example 1. Detailed Implementation
[0032] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.
[0033] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application. As used herein, the singular form includes the plural form unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this description, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0034] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0035] A method for preparing highly conductive and frost-resistant concrete for road surfaces in frigid regions includes the following steps:
[0036] Step S1: Weigh the following raw materials in parts by weight: 920-970 parts coarse aggregate, 720-760 parts fine aggregate, 480-510 parts cement, 225-240 parts water, 3.2-4.0 parts water-reducing agent, 8.0-12.5 parts carbon fiber, 70-85 parts steel fiber, 0.30-0.59 parts reduced graphene oxide, 0.30-1.18 parts dispersant, and 0.20-0.40 parts defoamer;
[0037] Step S2: Prepare a reduced graphene oxide dispersion;
[0038] Step S3: Add coarse aggregate, fine aggregate and steel fiber to the concrete mixer and mix for 45-75 seconds until the steel fiber is evenly dispersed to obtain the mixture;
[0039] Step S4: Add cement and 50% of the reduced graphene oxide dispersion prepared in step S2 to the mixture obtained in step S3, stir for 45-75 seconds to obtain the composite cementitious material.
[0040] Step S5: Add water-reducing agent and the remaining 50% of reduced graphene oxide dispersion to the composite cementitious material obtained in step S4, stir for 45-75s, slowly add carbon fiber during the process, and continue stirring for 45-75s to obtain the mixture.
[0041] Step S6: Pour the mixture obtained in step S5 into a mold for sample preparation, place it on a vibration table to vibrate and compact it, let it stand for 20-24 hours, then demold it and place it in a standard curing chamber for curing until the specified age.
[0042] The fine aggregate is natural river sand with a particle size ≤ 4.75 mm, a water absorption rate of 0.2%, and an apparent density of 2620 kg / m³. 3 Fineness modulus 2.5.
[0043] The steel fiber is copper-plated steel fiber, with a fiber length of 13mm, a single filament diameter of 200μm, and a density of 7.8g / cm³. 3 Tensile strength 2.85 GPa, volume resistivity 1.5 × 10⁻⁶ -5 Ω·cm, aspect ratio 65, volume fraction 1.0% vol.
[0044] The cement is P·O 42.5 ordinary Portland cement with an apparent density of 2963 kg / m³. 3 Specific surface area 350kg / m² 2 .
[0045] The water-reducing agent is a high-performance polycarboxylate water-reducing agent with a water reduction rate of 25%, a chloride ion content of 0.03%, an air content of 2.2%, a bleeding rate of 35%, a solid content of 39.8%, and a pH value of 6.25.
[0046] The carbon fiber is PAN-based carbon fiber, with a fiber length of 6 mm, a single filament diameter of 7.0–10 μm, a carbon content of ≥95%, and a density of 1.7 g / cm³. 3 Tensile strength 3.6–3.8 MPa, tensile modulus 220 GPa, volume resistivity 1.5 × 10⁻⁶ -3 Ω·cm, aspect ratio of 600–857, volume fraction of 0.6% vol.
[0047] Reduced graphene oxide is a multilayered reduced graphene oxide with a diameter of 10–50 μm, a thickness of 3.4–7.0 nm, 6–10 layers, a monolayer ratio of 30%, a purity >95 wt%, and a specific surface area of 450–550 m². 2 / g.
[0048] The dispersant is sodium dodecylbenzenesulfonate, an anionic surfactant, with a moisture content ≤3.0%, active ingredient 30-40%, unsaponifiable matter content ≤3.0%, sodium sulfate content ≤9.0%, pH value 7.5-8.5, and content 88%; the defoamer is tributyl phosphate, with a density of 0.974-0.980 g·ml, ≤0.002 mmol / g, moisture content ≤0.1%, and content ≥98.5%.
[0049] Step S2, which prepares the reduced graphene oxide dispersion, specifically includes the following steps:
[0050] Step S21: Add reduced graphene oxide, water, defoamer, and dispersant to a container to obtain a mixture;
[0051] Step S22: Use a magnetic stirrer to stir the mixture at a speed of 250 rad / min for 5 minutes. After the mixture is evenly dispersed and there is no obvious foam, pour it into multiple 50 ml centrifuge tubes.
[0052] Step S23: Set the temperature of the ultrasonic disperser to 50℃ and the frequency to 40kHz, and place multiple centrifuge tubes in the ultrasonic disperser to continue dispersing for 30 minutes.
[0053] Step S24: Remove the centrifuge tube and place it in tap water to cool to room temperature to obtain a reduced graphene oxide dispersion.
[0054] A highly conductive and frost-resistant concrete for use on traffic roads in frigid regions is prepared using the above-mentioned method.
[0055] Example 1
[0056] like Figure 1 The method for preparing highly conductive and highly frost-resistant concrete for road surfaces in frigid regions is characterized by the following steps:
[0057] Step S1: Accurately weigh the following raw materials using an electronic balance: 943 parts coarse aggregate, 741 parts fine aggregate, 494 parts cement, 232 parts water, 3.5 parts water-reducing agent, 10.2 parts carbon fiber, 78 parts steel fiber, 0.44 parts reduced graphene oxide, 0.88 parts dispersant, and 0.30 parts defoamer.
[0058] Step S2: Prepare a reduced graphene oxide dispersion;
[0059] Step S3: Add coarse aggregate, fine aggregate and steel fiber to the concrete mixer and mix for 60 seconds until the steel fiber is evenly dispersed to obtain the mixture;
[0060] Step S4: Add cement and 50% of the reduced graphene oxide dispersion prepared in step S2 to the mixture obtained in step S3, stir for 60 seconds to obtain the composite cementitious material.
[0061] Step S5: Add water-reducing agent and the remaining 50% of reduced graphene oxide dispersion to the composite cementitious material obtained in step S4, stir for 60s, slowly add carbon fiber during the process, and continue stirring for 60s to obtain the mixture.
[0062] Step S6: Pour the mixture obtained in step S5 into a mold for sample preparation, place it on a vibration table to vibrate and compact it, let it stand for 24 hours, then demold it and place it in a standard curing box for curing until the specified age.
[0063] Step S2, which prepares the reduced graphene oxide dispersion, specifically includes the following steps:
[0064] Step S21: Add reduced graphene oxide, water, defoamer and dispersant to a 500mL beaker to obtain a mixture;
[0065] Step S22: Use a magnetic stirrer to stir the mixture at a speed of 250 rad / min for 5 minutes. After the mixture is evenly dispersed and there is no obvious foam, pour it into multiple 50 ml centrifuge tubes.
[0066] Step S23: Set the temperature of the ultrasonic disperser to 50℃ and the frequency to 40kHz, and place multiple centrifuge tubes in the ultrasonic disperser to continue dispersing for 30 minutes.
[0067] Step S24: Remove the centrifuge tube and place it in tap water to cool to room temperature to obtain a reduced graphene oxide dispersion.
[0068] Example 2
[0069] The difference from Example 1 is that the raw materials in step S1 of this example are as follows:
[0070] 943 parts coarse aggregate, 741 parts fine aggregate, 494 parts cement, 232 parts water, 3.5 parts water-reducing agent, 10.2 parts carbon fiber, 78 parts steel fiber, 0.30 parts reduced graphene oxide, 0.60 parts dispersant, and 0.30 parts defoamer.
[0071] Example 3
[0072] The difference from Example 1 is that the raw materials in step S1 of this example are as follows:
[0073] 943 parts coarse aggregate, 741 parts fine aggregate, 494 parts cement, 232 parts water, 3.5 parts water-reducing agent, 10.2 parts carbon fiber, 78 parts steel fiber, 0.59 parts reduced graphene oxide, 1.18 parts dispersant, and 0.30 parts defoamer.
[0074] Comparative Example 1
[0075] The difference from Example 1 is that the raw materials used in step S1 of this comparative example are as follows:
[0076] 915 parts coarse aggregate, 719 parts fine aggregate, 506 parts cement, 238 parts water, 4 parts water-reducing agent, 10.2 parts carbon fiber, 78 parts steel fiber, 0.72 parts reduced graphene oxide, 1.42 parts dispersant, and 0.30 parts defoamer.
[0077] Comparative Example 2
[0078] The difference from Example 1 is that the raw materials used in step S1 of this comparative example are as follows:
[0079] 943 parts coarse aggregate, 741 parts fine aggregate, 494 parts cement, 232 parts water, 3.5 parts water-reducing agent, 10.2 parts carbon fiber, 78 parts steel fiber, 0.15 parts reduced graphene oxide, 0.30 parts dispersant, and 0.30 parts defoamer.
[0080] Comparative Example 3
[0081] The difference from Example 1 is that the raw materials used in step S1 of this comparative example are as follows:
[0082] 943 parts coarse aggregate, 741 parts fine aggregate, 494 parts cement, 232 parts water, 3.5 parts water-reducing agent, 10.2 parts carbon fiber, and 78 parts steel fiber.
[0083] Performance testing
[0084] The compressive strength and flexural strength of the specimens from the above embodiments and comparative examples, cured for 28 days and subjected to 300 freeze-thaw cycles, were tested according to the "Standard for Test Methods of Physical and Mechanical Properties of Concrete" (GB / T 50081-2019). The results are shown in Table 1. The resistivity of the specimens from the above embodiments cured for 28 days was tested according to Equation 1. The results are shown in Table 2.
[0085]
[0086] In the formula: ρ is the resistivity of the specimen (Ω·cm);
[0087] R is the resistance (Ω) of the specimen;
[0088] S is the cross-sectional area (cm²) between the electrodes perpendicular to the current direction. 2 );
[0089] L is the electrode spacing (cm);
[0090] U represents voltage (V);
[0091] I represents the steady current (A).
[0092] Table 1. Test results of compressive and flexural strength of the examples and comparative examples.
[0093]
[0094] Table 2 Resistivity test results of the examples and comparative examples
[0095]
[0096] During the mixing and molding process of concrete, the formation of its internal conductive pathways often exhibits a disordered distribution. Current theoretical discussions on the conductivity mechanism of concrete mainly focus on the seepage effect and the tunneling effect. When the content of reduced graphene oxide is below the seepage threshold, the tunneling effect plays a dominant role: when conductive particles are dispersed in the micro-gap region filled with hydrates, charge carriers can undergo electronic transitions under external energy excitation, forming tunnel conduction. When the content of reduced graphene oxide exceeds its seepage threshold, the seepage effect becomes the key mechanism. At this time, reduced graphene oxide can bridge steel fibers and carbon fibers in concrete to form a three-dimensional electron transport channel, forming a connected conductive network in the concrete matrix, and the conductivity increases significantly. After reaching the seepage threshold, further increasing the content of conductive fillers tends to saturate the effect on improving conductivity, and may even have negative effects due to filler agglomeration and other factors. Therefore, combining the above two conductivity theories, this study investigates the effect of reduced graphene oxide content on the conductivity of multiphase conductive concrete under the condition of steel fiber and carbon fiber co-addition.
[0097] As shown in Table 1, compared to Comparative Examples 1 to 3, the mechanical properties of the concrete specimens prepared in Examples 1 to 3 were significantly improved at 28 days of age and after undergoing 300 freeze-thaw cycles. As shown in Table 2, compared to Comparative Examples 1 to 3, the resistivity of the concrete specimens prepared in Examples 1 to 3 was significantly reduced at 28 days of age. The above two tables indicate that the addition of a certain amount of reduced graphene oxide helps improve the mechanical properties, freeze-thaw resistance, and electrical conductivity of conductive concrete. The main reason for this is:
[0098] (1) Reduced graphene oxide, as a nano-conductive material, can significantly improve the overall performance of conductive concrete due to its excellent mechanical properties and conductive properties. Its surface electron mobility is high, and the propagation rate of electron charge and lattice vibration in the graphene structure is extremely fast. Adding reduced graphene oxide can effectively reduce the spacing of conductive materials in conductive concrete, increase the probability of electron transition, and enhance the tunneling effect.
[0099] (2) Reduced graphene oxide can bridge steel fibers and carbon fibers in concrete to form a three-dimensional electron transport channel, which not only increases the conductive path, but also fills the micropores and improves the contact effect between conductive particles. These effects work together to reduce the resistivity of concrete, thereby simultaneously improving its mechanical and conductive properties.
[0100] (3) If the content of reduced graphene oxide exceeds 0.59 parts, due to its large specific surface area, it is prone to agglomeration. At the same time, reduced graphene oxide will adsorb more water, resulting in insufficient water for the formation of cement paste. The fluidity of the multiphase conductive recycled concrete continues to decrease, the hydration reaction is weakened, and excessive microcracks and pores are formed. The potential barrier between conductive materials increases, the probability of electron transition decreases, and the resistivity increases. However, if the content of reduced graphene oxide is less than 0.30 parts, it will be difficult to form a continuous and effective conductive network in the cement matrix due to insufficient dosage. The conductive phase distribution is too sparse, the electron transport path is interrupted, the carrier migration ability is significantly reduced, resulting in a high overall resistivity of the composite material, which cannot meet the expected conductivity requirements.
[0101] (4) Reduced graphene oxide itself has excellent mechanical properties and extremely high specific surface area, which can effectively fill the micropores and cracks inside the concrete, improve the density of the concrete, reduce the migration and accumulation of water inside the concrete, reduce the freezing expansion of water in the freeze-thaw cycle, and thus inhibit the damage of ice crystal formation to the concrete; this inhibitory effect helps to maintain the structural integrity of the concrete, thereby enhancing its freeze resistance.
[0102] However, when the amount of reduced graphene oxide exceeds 0.59 parts, due to its large specific surface area, it will adsorb more water, and excessive addition of reduced graphene oxide will also increase the porosity inside the concrete. During freeze-thaw cycles, the freezing and expansion of water in these pores will cause more severe damage to the concrete. In addition, the introduction of excessive reduced graphene oxide may lead to uneven stress distribution inside the concrete, forming stress concentration areas. Under freeze-thaw action, these areas are more prone to crack formation and propagation, thereby accelerating the decline in compressive strength. If the amount of reduced graphene oxide is less than 0.30 parts, due to insufficient dispersion in the cement matrix, it is difficult to effectively overlap and form a reinforcing network, and its effect on improving the microstructure of concrete is limited. In freeze-thaw environments, it is insufficient to inhibit the damage caused by water intrusion and ice crystal expansion, and it cannot effectively alleviate internal stress concentration, resulting in no significant improvement in freeze-thaw resistance and compressive strength.
[0103] By comparing the above embodiments and comparative examples, the compressive strength and flexural strength of the high-conductivity, high-frost-resistant concrete prepared in the embodiments are significantly higher than those in the comparative examples, while the resistivity is significantly lower. Therefore, the high-conductivity, high-frost-resistant concrete prepared by this invention for use on traffic roads in frigid regions exhibits excellent performance, can adapt to the frigid environment, and meets the service life requirements of such regions.
[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A method for preparing highly conductive and highly frost-resistant concrete for road surfaces in frigid regions, characterized in that: Specifically comprising the following steps: Step S1, taking the following weight parts of raw materials, coarse aggregate 920-970 parts, fine aggregate 720-760 parts, cement 480-510 parts, water 225-240 parts, water reducing agent 3.2-4.0 parts, carbon fiber 8.0-12.5 parts, steel fiber 70-85 parts, reduced graphene oxide 0.30-0.59 parts, dispersant 0.30-1.18 parts, defoaming agent 0.20-0.40 parts; Step S2, preparing a reduced graphene oxide dispersion liquid; Step S3, adding coarse aggregate, fine aggregate and steel fiber into a concrete mixer, stirring for 45-75s until the steel fiber is uniformly dispersed, to obtain a mixture; Step S4, adding cement and 50% of the reduced graphene oxide dispersion liquid prepared in step S2 into the mixture prepared in step S3, stirring for 45-75s, to obtain a composite cementitious material; Step S5, adding water reducing agent and the remaining 50% of the reduced graphene oxide dispersion liquid into the composite cementitious material prepared in step S4, stirring for 45-75s, during which carbon fiber is slowly added, and continue stirring for 45-75s to obtain a mixture; Step S6, pouring the mixture prepared in step S5 into a mold to prepare a sample, placing it on a vibration table to vibrate and compact, demolding after standing for 20-24h, and placing it in a standard curing box for curing until the specified age.
2. The method for preparing high-conductivity and high-anti-freezing concrete applied to traffic pavement in severe cold area according to claim 1, characterized in that: The fine aggregate is natural river sand with a particle size of ≤ 4.75 mm, a water absorption of 0.2%, and an apparent density of 2620 kg / m 3 , with a fineness modulus of 2.
5.
3. The method for preparing high-conductivity and high-anti-freezing concrete applied to traffic pavement in severe cold area according to claim 1, characterized in that: The steel fiber is a copper-plated steel fiber, with a fiber length of 13 mm, a single wire diameter of 200 μm, a density of 7.8 g / cm 3 , a tensile strength of 2.85 GPa, a volume resistivity of 1.5 x 10 -5 Ω-cm, a length-diameter ratio of 65, and a volume content of 1.0% vol.
4. The method for preparing high-conductivity and high-anti-freezing concrete applied to traffic pavement in severe cold area according to claim 1, characterized in that: The cement is P·O 42.5 ordinary portland cement, apparent density 2963 kg / m 3 Specific surface area 350 kg / m 2 .
5. The method for preparing high-conductivity and high-anti-freezing concrete applied to traffic pavement in severe cold area according to claim 1, characterized in that: The water reducing agent is a polycarboxylic acid high-performance water reducing agent, with a water reducing rate of 25%, a chloride ion content of 0.03%, an air content of 2.2%, a bleeding rate of 35%, a solid content of 39.8%, and a pH value of 6.
25.
6. The method for preparing high-conductivity and high-anti-freezing concrete applied to traffic pavement in severe cold area according to claim 1, characterized in that: The carbon fiber is PAN-based carbon fiber, fiber length 6 mm, single filament diameter 7.0-10 μm, carbon content ≥ 95%, density 1.7 g / cm 3 , tensile strength 3.6-3.8 MPa, tensile modulus 220 GPa, volume resistivity 1.5 x 10 -3 Ω-cm, aspect ratio 600-857, volume content 0.6% vol.
7. The method for preparing high-conductivity and high-anti-freezing concrete applied to traffic pavement in severe cold area according to claim 1, characterized in that: The reduced graphene oxide is multi-layer reduced graphene oxide, with a diameter of 10-50 microns, a thickness of 3.4-7.0 nanometers, a layer number of 6-10, a single layer rate of 30%, a purity of >95wt%, and a specific surface area of 450-550 m 2 / g.
8. The method for preparing high-conductivity and high-anti-freezing concrete applied to traffic pavement in severe cold area according to claim 1, characterized in that: The dispersant is an anionic surfactant sodium dodecyl benzene sulfonate, with water content ≤3.0%, active substance 30-40%, unsaponifiable matter content ≤3.0%, sodium sulfate content ≤9.0%, pH value 7.5-8.5, and content 88%; The defoaming agent is tributyl phosphate, with a density of 0.974-0.980 g·ml, ≤0.002 mmol / g, water content ≤0.1%, and content ≥98.5%.
9. The method for preparing high-conductivity and high-anti-freezing concrete applied to traffic pavement in severe cold area according to claim 1, characterized in that: The step S2 of preparing a reduced graphene oxide dispersion liquid specifically comprises the following steps: Step S21, adding reduced graphene oxide, water, defoaming agent and dispersant into a container to prepare a mixture; Step S22, stirring the mixture with a magnetic stirrer at a speed of 250 rad / min for 5 min, and after the mixture is uniformly dispersed and there is no obvious foam, pouring it into multiple 50 ml centrifuge tubes; Step S23, setting the temperature of the ultrasonic disperser to 50℃ and the frequency to 40 kHz, and placing the multiple centrifuge tubes in the ultrasonic disperser for further dispersion for 30 min; Step S24, taking out the centrifuge tubes and cooling them to room temperature in tap water to obtain a reduced graphene oxide dispersion liquid.
10. A high-conductivity high-anti-freezing concrete applied to traffic pavement in cold regions, characterized in that: The high-conductivity high-frost-resistance concrete is prepared by the method according to any one of claims 1-9.