Durable high-tenacity concrete and process for its production

Abstract

The application discloses a kind of durable high toughness concrete and preparation process thereof, and relates to the technical field of concrete preparation.The concrete includes cement, fly ash, silica fume, medium sand, gravel, modified polyethylene fiber, water reducing agent, expanding agent and water.The modified polyethylene fiber is modified in two steps: firstly, a modified graphene coating layer is loaded on the surface of the fiber, and then a silica layer is deposited by sol-gel method.The modified graphene coating layer and the silica layer greatly improve the interfacial bonding strength between the polyethylene fiber and the cement matrix, and effectively resist the corrosion of cement alkali environment.The concrete prepared by the application has high toughness, high impermeability and excellent durability, and is suitable for high-rise buildings, bridges, tunnels, protective engineering and other structures with high durability requirements.

Description

Technical Field

[0001] This invention relates to the field of concrete preparation technology, specifically to a durable, high-toughness concrete and its preparation process. Background Technology

[0002] Concrete is the most widely used man-made material in construction engineering, but its inherent brittleness, low tensile strength, and susceptibility to cracking severely limit its application in high-rise buildings, long-span bridges, marine engineering, and military protection. To improve the toughness and crack resistance of concrete, researchers have experimented with incorporating fibers (such as steel fibers, polypropylene fibers, polyvinyl alcohol fibers, and polyethylene fibers) into concrete. These fibers can inhibit the propagation of microcracks within the concrete matrix through bridging, thereby improving the concrete's deformation capacity and toughness.

[0003] For example, Chinese patent CN115159929A ​​discloses a method for preparing ultra-high performance concrete. This patent improves the bonding ability of ultra-high molecular weight polyethylene fibers by surface modification, but does not mention the toughness and durability of the concrete.

[0004] In summary, to solve the above problems, this invention proposes a durable and high-toughness concrete and its preparation process. Summary of the Invention

[0005] The purpose of this invention is to provide a durable and high-toughness concrete and its preparation process to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A durable and high-toughness concrete, comprising, by weight, 100-120 parts cement, 15-30 parts fly ash, 10-15 parts silica fume, 120-140 parts medium sand, 230-250 parts crushed stone, 5-10 parts modified polyethylene fiber, 3-5 parts water-reducing agent, 8-10 parts expansion agent, and 30-40 parts water.

[0007] Furthermore, the modified polyethylene fiber is obtained by the following process: (1) Add polyethylene fiber to the treatment solution, heat to 40-50℃, stir at 100-150rpm for 30-45min, then heat to 60-70℃ and keep warm for 2-3h, take it out and dry at 60-70℃ for 15-20h to obtain modified graphene-coated polyethylene fiber. (2) Mix ethanol and ammonia, then add modified graphene-coated polyethylene fiber, add tetraethyl orthosilicate at a stirring speed of 100-150 rpm, and continue stirring for 10-12 h. After washing with ethanol, ultrasonic cleaning, and drying, the modified polyethylene fiber is obtained.

[0008] Furthermore, in step (1), the polyethylene fiber has a length of 12 mm and a diameter of 24 μm; The polyethylene fibers are ultrasonically cleaned with deionized water before use. The ultrasonic cleaning process conditions are: ultrasonic power of 150-300W and time of 15-30min.

[0009] Further, in step (2), the treatment liquid includes the following components by mass: 15-20 parts modified graphene dispersion, 2-3 parts water-reducing agent, and 1500-2000 parts water; The water-reducing agent is a polycarboxylate water-reducing agent with a water reduction rate of 35%.

[0010] Furthermore, in step (3), the ratio of ethanol, ammonia, modified graphene-coated polyethylene fiber, and tetraethyl orthosilicate is (50-60)mL:(1.5-2)mL:2g:(0.2-0.25)mL; The concentration of ammonia water is 25-30 wt%.

[0011] Furthermore, the modified graphene dispersion is prepared by the following process: Step 1: Disperse graphene oxide in deionized water to obtain a graphene oxide dispersion. Step 2: Indium trichloride tetrahydrate, urea, and sodium citrate are added sequentially to the graphene oxide dispersion. The mixture is reacted in a reactor at 135-145℃ for 10-12 hours. After centrifugation and washing, the mixture is dispersed in deionized water to prepare the modified graphene dispersion.

[0012] Furthermore, in step 1, the thickness of the graphene oxide is 1-5 nm and the diameter is 2-8 μm; The mass concentration of the graphene oxide dispersion is 1-2%.

[0013] Further, in step 2, the mass ratio of indium trichloride tetrahydrate, urea, sodium citrate, and graphene oxide dispersion is (0.4-0.5):(3-4):(1-1.5):10; The mass concentration of the modified graphene dispersion is 0.5-1.5%.

[0014] In the above technical solution, urea decomposes in the reactor to produce ammonia, which dissolves in water to form an alkaline environment; indium ions hydrolyze and deposit on the surface of graphene oxide.

[0015] Furthermore, the cement is P·Ⅱ 52.5 silicate cement.

[0016] Furthermore, the fly ash is FII grade low-calcium fly ash.

[0017] Furthermore, the silicon powder contains 95% silicon dioxide by mass and has a specific surface area of ​​15500 m². 2 / kg.

[0018] Furthermore, the medium sand is quartz sand.

[0019] Furthermore, the gravel is basalt gravel with an average particle size of 10-20 mm.

[0020] Furthermore, the water-reducing agent is a polycarboxylate water-reducing agent with a water reduction rate of 35%.

[0021] Furthermore, the expanding agent is a UEA type II expanding agent.

[0022] A process for preparing durable and high-toughness concrete includes the following steps: Cement, fly ash, silica fume, medium sand, and crushed stone are mixed and stirred evenly. Then, modified polyethylene fiber, water-reducing agent, expansion agent, and water are added and stirred continuously until evenly mixed to prepare durable and high-toughness concrete.

[0023] Compared with the prior art, the beneficial effects achieved by the present invention are: This invention significantly improves the roughness of graphene oxide by preparing nano-indium hydroxide particles on the surface of graphene oxide. These particles are then used to modify polyethylene fibers, increasing the surface roughness of the polyethylene fibers and thus enhancing the interfacial bonding between the polyethylene fibers and the silica layer. Furthermore, the modified graphene interacts with the silica layer, further strengthening the interfacial bonding between the polyethylene fibers and the silica layer. In addition, graphene oxide has excellent barrier properties, effectively preventing moisture and corrosive ions from eroding the polyethylene fiber body.

[0024] This invention utilizes a sol-gel method to in-situ deposit a dense silica layer on the surface of graphene oxide-encapsulated polyethylene fibers. The silica layer surface is rich in silanol groups, which can react with cement hydration products to generate gel products such as CSH, improving the interfacial bonding between the polyethylene fibers and cement. This allows the modified polyethylene fibers to bond tightly to the cement matrix, inhibiting the propagation of matrix cracks and thus improving the fatigue resistance of concrete. Simultaneously, silica promotes the hydration reaction of tricalcium silicate in cement, increasing the degree of cement hydration and consequently enhancing concrete strength. Furthermore, the silica layer effectively blocks alkaline substances from eroding the polyethylene fibers, ensuring stable performance in alkaline cement environments. Polyethylene fibers possess excellent properties such as low density, high tensile strength, high elastic modulus, and chemical corrosion resistance, making them an effective concrete reinforcement material that improves the toughness and durability of concrete.

[0025] The concrete of this invention uses cement, fly ash, and silica fume as the matrix, medium sand and crushed stone as aggregates, and incorporates polycarboxylate superplasticizer and modified polyethylene fiber. Fly ash and silica fume can refine the pore structure, reduce the heat of hydration, and improve the strength of concrete. The superplasticizer ensures the fluidity and workability of the mixture. The expansion agent compensates for shrinkage and inhibits early cracking. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0027] It should be noted that the following quantities are by weight. There are no special restrictions on the manufacturers of the raw materials used in this invention. Exemplary examples include: in the following embodiments, the cement is P·II 52.5 silicate cement; the fly ash is FII grade low-calcium fly ash; the silica powder has a silica content of 95% and a specific surface area of ​​15500 m². 2 / kg; medium sand is quartz sand; crushed stone is basalt crushed stone with an average particle size of 20mm; water-reducing agent is polycarboxylate water-reducing agent with a water reduction rate of 35%; expansion agent is UEA type II expansion agent; other raw materials are all commercially available.

[0028] Example 1: A process for preparing durable and high-toughness concrete, comprising the following steps: S1: Preparation of treatment solution S1-1: Graphene oxide is dispersed in deionized water to prepare a graphene oxide dispersion with a mass concentration of 1.5%. S1-2: Indium trichloride tetrahydrate, urea, and sodium citrate were added sequentially to the graphene oxide dispersion. The mixture was reacted at 140°C for 11 hours in a reactor. After centrifugation and washing, the mixture was dispersed in deionized water to prepare a modified graphene dispersion with a mass concentration of 1%. The mass ratio of indium trichloride tetrahydrate, urea, sodium citrate, and graphene oxide dispersion was 0.45:3.5:1.2:10. S1-3: Mix 18 parts of modified graphene dispersion, 2.5 parts of water-reducing agent, and 1800 parts of water to obtain the treatment solution; S2: Preparation of modified polyethylene fibers S2-1: Polyethylene fibers are added to deionized water and cleaned for 20 minutes under ultrasonic power of 200W to prepare pretreated polyethylene fibers. S2-2: Add the pretreated polyethylene fiber to the treatment solution, heat to 45℃, stir at 120 rpm for 40 min, then heat to 65℃ and keep warm for 2.5 h, take it out and dry at 65℃ for 18 h to obtain the modified graphene-coated polyethylene fiber. S2-3: Ethanol and ammonia were mixed, and then modified graphene-coated polyethylene fibers were added. Ethyl orthosilicate was added while stirring at 120 rpm, and the reaction was continued for 11 hours. After washing with ethanol, ultrasonic cleaning, and drying, modified polyethylene fibers were obtained. The ratio of ethanol, ammonia, modified graphene-coated polyethylene fibers, and ethyl orthosilicate was 55 mL:1.8 mL:2 g:0.22 mL; the concentration of ammonia was 28 wt%. S3: Mix cement, fly ash, silica fume, medium sand, and crushed stone evenly, then add modified polyethylene fiber, water-reducing agent, expansion agent, and water and continue mixing. After mixing evenly, durable and high-toughness concrete is prepared. The durable and high-toughness concrete comprises, by weight, 110 parts cement, 20 parts fly ash, 12 parts silica fume, 130 parts medium sand, 240 parts crushed stone, 6 parts modified polyethylene fiber, 4 parts water-reducing agent, 9 parts expansion agent, and 35 parts water.

[0029] Example 2: A process for preparing durable and high-toughness concrete, comprising the following steps: S1: Preparation of treatment solution S1-1: Graphene oxide is dispersed in deionized water to prepare a graphene oxide dispersion with a mass concentration of 1%. S1-2: Indium trichloride tetrahydrate, urea, and sodium citrate were added sequentially to the graphene oxide dispersion. The mixture was reacted at 135°C for 12 hours in a reactor. After centrifugation and washing, the mixture was dispersed in deionized water to prepare a modified graphene dispersion with a mass concentration of 0.5%. The mass ratio of indium trichloride tetrahydrate, urea, sodium citrate, and graphene oxide dispersion was 0.4:3:1:10. S1-3: Mix 15 parts of modified graphene dispersion, 2 parts of water-reducing agent, and 1500 parts of water to obtain the treatment solution; S2: Preparation of modified polyethylene fibers S2-1: Polyethylene fibers are added to deionized water and cleaned for 30 minutes under ultrasonic power of 150W to prepare pretreated polyethylene fibers. S2-2: Add the pretreated polyethylene fiber to the treatment solution, heat to 40℃, stir at 100 rpm for 30 min, then heat to 60℃ and keep warm for 3 h, take it out and dry at 60℃ for 20 h to obtain the modified graphene-coated polyethylene fiber. S2-3: Ethanol and ammonia were mixed, and then modified graphene-coated polyethylene fibers were added. Ethyl orthosilicate was added while stirring at 100 rpm, and the reaction was continued for 12 hours. After washing with ethanol, ultrasonic cleaning, and drying, modified polyethylene fibers were obtained. The ratio of ethanol, ammonia, modified graphene-coated polyethylene fibers, and ethyl orthosilicate was 50 mL:1.5 mL:2 g:0.2 mL; the concentration of ammonia was 25 wt%. S3: Mix cement, fly ash, silica fume, medium sand, and crushed stone evenly, then add modified polyethylene fiber, water-reducing agent, expansion agent, and water and continue mixing. After mixing evenly, durable and high-toughness concrete is prepared. The durable and high-toughness concrete comprises, by weight, 100 parts cement, 15 parts fly ash, 10 parts silica fume, 120 parts medium sand, 230 parts crushed stone, 5 parts modified polyethylene fiber, 3 parts water-reducing agent, 8 parts expansion agent, and 30 parts water.

[0030] Example 3: A preparation process for durable and high-toughness concrete, comprising the following steps: S1: Preparation of treatment solution S1-1: Graphene oxide is dispersed in deionized water to obtain a graphene oxide dispersion with a mass concentration of 2%. S1-2: Indium trichloride tetrahydrate, urea, and sodium citrate were added sequentially to the graphene oxide dispersion. The mixture was reacted at 145°C for 10 hours in a reactor. After centrifugation and washing, the mixture was dispersed in deionized water to prepare a modified graphene dispersion with a mass concentration of 1.5%. The mass ratio of indium trichloride tetrahydrate, urea, sodium citrate, and graphene oxide dispersion was 0.5:4:1.5:10. S1-3: Mix 20 parts of modified graphene dispersion, 3 parts of water-reducing agent, and 2000 parts of water to prepare a treatment solution; S2: Preparation of modified polyethylene fibers S2-1: Polyethylene fibers are added to deionized water and cleaned for 15 minutes under ultrasonic power of 300W to prepare pretreated polyethylene fibers. S2-2: Add the pretreated polyethylene fiber to the treatment solution, heat to 50℃, stir at 150 rpm for 45 min, then heat to 70℃ and keep warm for 2 h, take it out and dry at 70℃ for 15 h to obtain the modified graphene-coated polyethylene fiber. S2-3: Ethanol and ammonia were mixed, and then modified graphene-coated polyethylene fibers were added. Tetraethyl orthosilicate was added while stirring at 150 rpm, and the reaction was continued for 10 hours. After washing with ethanol, ultrasonic cleaning, and drying, modified polyethylene fibers were obtained. The ratio of ethanol, ammonia, modified graphene-coated polyethylene fibers, and tetraethyl orthosilicate was 60 mL:2 mL:2 g:0.25 mL; the concentration of ammonia was 30 wt%. S3: Mix cement, fly ash, silica fume, medium sand, and crushed stone evenly, then add modified polyethylene fiber, water-reducing agent, expansion agent, and water and continue mixing. After mixing evenly, durable and high-toughness concrete is prepared. The durable and high-toughness concrete comprises, by weight, 120 parts cement, 30 parts fly ash, 15 parts silica fume, 140 parts medium sand, 250 parts crushed stone, 10 parts modified polyethylene fiber, 5 parts water-reducing agent, 10 parts expansion agent, and 40 parts water.

[0031] Comparative Example 1: Based on Example 1, without the addition of modified polyethylene fiber. The difference from Example 1 is that the durable high-toughness concrete by weight includes: 110 parts cement, 20 parts fly ash, 12 parts silica fume, 130 parts medium sand, 240 parts crushed stone, 4 parts water-reducing agent, 9 parts expansion agent, and 35 parts water.

[0032] Comparative Example 2: Based on Example 1, the modified polyethylene fiber was replaced with an equal mass of polyethylene fiber. The difference from Example 1 is that the durable high-toughness concrete by mass parts includes: 110 parts cement, 20 parts fly ash, 12 parts silica fume, 130 parts medium sand, 240 parts crushed stone, 6 parts polyethylene fiber, 4 parts water-reducing agent, 9 parts expansion agent, and 35 parts water.

[0033] Comparative Example 3: Based on Example 1, the preparation process of modified polyethylene fiber was adjusted. The difference from Example 1 is that a preparation process for durable and high-toughness concrete includes the following steps: S1: Preparation of treatment solution S1-1: Graphene oxide is dispersed in deionized water to prepare a graphene oxide dispersion with a mass concentration of 1.5%. S1-2: Indium trichloride tetrahydrate, urea, and sodium citrate were added sequentially to the graphene oxide dispersion. The mixture was reacted at 140°C for 11 hours in a reactor. After centrifugation and washing, the mixture was dispersed in deionized water to prepare a modified graphene dispersion with a mass concentration of 1%. The mass ratio of indium trichloride tetrahydrate, urea, sodium citrate, and graphene oxide dispersion was 0.45:3.5:1.2:10. S1-3: Mix 18 parts of modified graphene dispersion, 2.5 parts of water-reducing agent, and 1800 parts of water to obtain the treatment solution; S2: Preparation of modified polyethylene fibers S2-1: Polyethylene fibers are added to deionized water and cleaned for 20 minutes under ultrasonic power of 200W to prepare pretreated polyethylene fibers. S2-2: Add the pretreated polyethylene fiber to the treatment solution, heat to 45℃, stir at 120 rpm for 40 min, then heat to 65℃ and keep warm for 2.5 h, take it out and dry at 65℃ for 18 h to obtain modified polyethylene fiber. S3: Mix cement, fly ash, silica fume, medium sand, and crushed stone evenly, then add modified polyethylene fiber, water-reducing agent, expansion agent, and water and continue mixing. After mixing evenly, durable and high-toughness concrete is prepared. The durable and high-toughness concrete comprises, by weight, 110 parts cement, 20 parts fly ash, 12 parts silica fume, 130 parts medium sand, 240 parts crushed stone, 6 parts modified polyethylene fiber, 4 parts water-reducing agent, 9 parts expansion agent, and 35 parts water.

[0034] Comparative Example 4: Based on Example 1, the preparation process of modified polyethylene fiber was adjusted. The difference from Example 1 is that a preparation process for durable and high-toughness concrete includes the following steps: S1: Preparation of modified polyethylene fibers S1-1: Polyethylene fibers are added to deionized water and cleaned for 20 minutes under ultrasonic power of 200W to prepare pretreated polyethylene fibers. S1-2: Ethanol and ammonia were mixed, and then pretreated polyethylene fibers were added. Ethyl orthosilicate was added while stirring at 120 rpm, and the reaction was continued for 11 hours. After washing with ethanol, ultrasonic cleaning, and drying, modified polyethylene fibers were obtained. The ratio of ethanol, ammonia, pretreated polyethylene fibers, and ethyl orthosilicate was 55 mL:1.8 mL:2 g:0.22 mL; the concentration of ammonia was 28 wt%. S3: Mix cement, fly ash, silica fume, medium sand, and crushed stone evenly, then add modified polyethylene fiber, water-reducing agent, expansion agent, and water and continue mixing. After mixing evenly, durable and high-toughness concrete is prepared. The durable and high-toughness concrete comprises, by weight, 110 parts cement, 20 parts fly ash, 12 parts silica fume, 130 parts medium sand, 240 parts crushed stone, 6 parts modified polyethylene fiber, 4 parts water-reducing agent, 9 parts expansion agent, and 35 parts water.

[0035] Performance Test 1: The durable and high-toughness concrete prepared in the examples and comparative examples was cured for 28 days at 20°C and 95% relative humidity. The compressive strength and flexural strength of the concrete were then tested using an electronic universal testing machine. The sample size for the compressive strength test was 100mm×100mm×100mm, and the sample size for the flexural strength test was 100mm×100mm×400mm. The loading speed was 2mm / min, and each sample needed to be tested at least three times. The toughness of the concrete was expressed as the flexural-compression ratio, which is the ratio of the flexural strength to the compressive strength of the concrete. The larger the flexural-compression ratio, the better the toughness of the concrete.

[0036] Performance Test 2: The durable and high-toughness concrete prepared in the examples and comparative examples was cured for 28 days at 20°C and 95% relative humidity. The water absorption rate of the concrete was determined according to ASTM C 1403-22a. The dry weight (M1) of the concrete after drying in an oven at 110°C for 24 hours was recorded, and the weight (M2) of the concrete after soaking in water for 24 hours was measured. The water absorption rate (WAA) was calculated by the following formula: WAA=((M2-M1) / M1)×100%.

[0037] Performance Test 3: The modified polyethylene fibers prepared in the examples and comparative examples were immersed in a 1 mol / L sodium hydroxide solution at room temperature for three days. After immersion, they were taken out, rinsed with deionized water, and then dried at 60°C for 24 hours. The mass retention rate of the modified polyethylene fibers was calculated.

[0038] Performance Test 4: The durable and high-toughness concrete prepared in the examples and comparative examples was cured for 28 days at 20℃ and 95% relative humidity. Specimens with dimensions of 160mm×40mm×40mm were then prepared and subjected to a three-point bending fatigue test with a span of 100mm, sinusoidal loading at a frequency of 10Hz, and a loading rate of 50N / s up to a load of 3.5kN. The fatigue resistance of the concrete was tested, and the number of cycles at specimen failure was recorded. The average value of three specimens in each group was taken.

[0039]

[0040] Conclusion: As can be seen from the data in the table above, the performance of the durable and high-toughness concrete prepared in Comparative Examples 1-4 is significantly worse than that of the durable and high-toughness concrete prepared in Examples 1-3.

[0041] Comparative Example 1, based on Example 1, did not include modified polyethylene fibers. The resulting durable and high-toughness concrete exhibited poorer performance, indicating that the addition of modified polyethylene fibers is key to improving the mechanical properties and impermeability of concrete.

[0042] Comparative Example 2, based on Example 1, replaced the modified polyethylene fiber with an equal mass of polyethylene fiber. Due to the smooth surface of the unmodified fiber and its weak interfacial bonding with the cement matrix, the performance of the prepared durable and high-toughness concrete deteriorated, indicating that the unmodified polyethylene fiber could not effectively improve the compressive strength, flexural strength, and fatigue resistance of the concrete.

[0043] Comparative Example 3, based on Example 1, adjusted the preparation process of the modified polyethylene fiber, only modifying it with graphene. The resulting durable and tough concrete had poorer performance, indicating that only modifying the polyethylene fiber with graphene lacks the chemical bonding and alkali resistance of the silica layer, and cannot fully exert the bridging and toughening effect of the fiber, resulting in limited improvement in fatigue resistance.

[0044] Comparative Example 4, based on Example 1, adjusted the preparation process of the modified polyethylene fiber, performing only silica modification. The resulting durable and high-toughness concrete exhibited poorer performance. This indicates that although silica modification alone can give the fiber surface a certain degree of pozzolanic activity and allow it to chemically bond with cement hydration products, the lack of a rough interface provided by the modified graphene layer results in weak bonding between the silica layer and the fiber body. Consequently, it is difficult to maintain stable interfacial properties during long-term use, leading to a significant reduction in the fatigue resistance of the concrete.

[0045] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A durable and high-toughness concrete, characterized in that: The components, by weight, are: 100-120 parts cement, 15-30 parts fly ash, 10-15 parts silica fume, 120-140 parts medium sand, 230-250 parts crushed stone, 5-10 parts modified polyethylene fiber, 3-5 parts water-reducing agent, 8-10 parts expansion agent, and 30-40 parts water. The modified polyethylene fiber is obtained by the following process: (1) Add polyethylene fiber to the treatment solution, heat to 40-50℃, stir at 100-150rpm for 30-45min, then heat to 60-70℃ and keep warm for 2-3h. Take out the polyethylene fiber and dry it to obtain modified graphene-coated polyethylene fiber. (2) Mix ethanol and ammonia, then add modified graphene-coated polyethylene fiber, add tetraethyl orthosilicate at a stirring speed of 100-150 rpm, and continue stirring for 10-12 h. After washing with ethanol, ultrasonic cleaning, and drying, the modified polyethylene fiber is obtained.

2. The durable and high-toughness concrete according to claim 1, characterized in that: In step (1), the treatment liquid comprises the following components by mass: 15-20 parts modified graphene dispersion, 2-3 parts water-reducing agent, and 1500-2000 parts water.

3. The durable and high-toughness concrete according to claim 2, characterized in that: The modified graphene dispersion was prepared by the following process: Step 1: Disperse graphene oxide in deionized water to obtain a graphene oxide dispersion. Step 2: Indium trichloride tetrahydrate, urea, and sodium citrate are added sequentially to the graphene oxide dispersion. The mixture is reacted in a reactor at 135-145℃ for 10-12 hours. After centrifugation and washing, the mixture is dispersed in deionized water to prepare the modified graphene dispersion.

4. The durable and high-toughness concrete according to claim 3, characterized in that: In step 1, the mass concentration of the graphene oxide dispersion is 1-2%.

5. The durable and high-toughness concrete according to claim 3, characterized in that: In step 2, the mass ratio of indium trichloride tetrahydrate, urea, sodium citrate, and graphene oxide dispersion is (0.4-0.5):(3-4):(1-1.5):

10.

6. The durable and high-toughness concrete according to claim 3, characterized in that: The mass concentration of the modified graphene dispersion is 0.5-1.5%.

7. The durable and high-toughness concrete according to claim 1, characterized in that: In step (2), the ratio of ethanol, ammonia, modified graphene-coated polyethylene fiber, and tetraethyl orthosilicate is (50-60)mL:(1.5-2)mL:2g:(0.2-0.25)mL.

8. The durable and high-toughness concrete according to claim 1, characterized in that: The polyethylene fibers are ultrasonically cleaned with deionized water before use.

9. The durable and high-toughness concrete according to claim 8, characterized in that: The ultrasonic cleaning process conditions are: ultrasonic power of 150-300W and time of 15-30min.

10. A process for preparing durable and high-toughness concrete, characterized in that: Includes the following steps: Cement, fly ash, silica fume, medium sand, and crushed stone are mixed and stirred evenly. Then, modified polyethylene fiber, water-reducing agent, expansion agent, and water are added and stirred continuously until evenly mixed to prepare durable and high-toughness concrete.

Images