Fiber-reinforced ultra-high performance concrete pole and preparation method thereof

Abstract

The invention relates to the field of concrete electric poles, in particular to a fiber-reinforced ultra-high-performance concrete electric pole and a preparation method thereof, and aims to solve the problems that a traditional concrete electric pole is poor in waterproof and waterproof performance and mechanical performance, short in service life in a severe environment and difficult to meet strict requirements of ultra-high voltage and long-distance power transmission. According to the preparation method, the modified polydopamine coated basalt fiber and the multi-epoxy fluorine-containing compound are added into the electric pole, so that the waterproof performance and the mechanical performance of the electric pole can be remarkably improved, the overall performance of the electric pole is greatly improved, and the service life of the electric pole in a severe environment can be remarkably prolonged; therefore, the long-term reliability and safety of the electric pole are ensured, the electric pole can meet the use requirements of different severe environments and engineering scenes, and high-quality development of electric power engineering construction is promoted.

Description

A fiber-reinforced ultra-high performance concrete pole and its preparation method Technical Field

[0001] This invention relates to the field of concrete poles, and more specifically to a fiber-reinforced ultra-high performance concrete pole and its preparation method. Background Technology

[0002] As the core supporting component of power transmission lines, the performance of concrete poles directly determines the safety, reliability, and service life of these lines. With power construction extending to harsh environments such as coastal areas, high-altitude regions, and plateaus, traditional concrete poles have insufficient mechanical properties. They are prone to bending and breakage under extreme loads such as strong winds and icing. Furthermore, the numerous capillary channels within concrete allow for the penetration of corrosive media such as moisture, accelerating internal damage and making it difficult to meet the stringent requirements of ultra-high voltage and long-distance power transmission.

[0003] Therefore, developing a fiber-reinforced ultra-high performance concrete pole and its preparation method is of great practical significance. Summary of the Invention

[0004] In order to overcome the above-mentioned technical problems, the purpose of this invention is to provide a fiber-reinforced ultra-high performance concrete pole and its preparation method, which solves the problems of poor waterproof and water-resistant performance and mechanical properties of traditional concrete poles, short service life in harsh environments, and difficulty in meeting the stringent requirements of ultra-high voltage and long-distance power transmission.

[0005] The objective of this invention can be achieved through the following technical solution: Firstly, this application provides a fiber-reinforced ultra-high performance concrete pole, comprising the following components by weight: 60-70 parts cement, 75-80 parts coarse aggregate, 50-55 parts fine aggregate, 10-16 parts nano-silica, 2-3 parts water-reducing agent, 1.5-8.5 parts modified polydopamine-coated basalt fiber, 1-7 parts polyepoxy fluorinated compound, and 25-30 parts water; wherein the modified polydopamine-coated basalt fiber is prepared by the following steps: Step A1: Tris(hydroxymethyl)aminomethane hydrochloride and deionized water are added to a three-necked flask equipped with a stirrer and thermometer, and stirred for 10-15 minutes at a temperature of 20-25°C and a stirring rate of 200-300 r / min. Then, the pH is adjusted to 8.5 with sodium hydroxide solution, followed by the addition of basalt fiber and dopamine hydrochloride, and the stirring reaction continues for 20 minutes. -30h. After the reaction is completed, the reaction product is vacuum filtered. The filter cake is washed 2-3 times with saturated sodium bicarbonate solution and distilled water, and then placed in a vacuum drying oven and dried at 50-60℃ for 4-5h to obtain polydopamine-coated basalt fiber; Step A2: Polydopamine-coated basalt fiber, 3-aminopropyltriethoxysilane, triethylamine and anhydrous ethanol are added to a three-necked flask equipped with a stirrer and thermometer. The mixture is stirred at 20-25℃ and a stirring rate of 200-300r / min for 10-15min. Then the temperature is raised to 60-70℃ and the stirring is continued for 15-20h. After the reaction is completed, the reaction product is cooled to room temperature and then centrifuged. The precipitate is washed 2-3 times with distilled water and then placed in a vacuum drying oven and dried at 70-80℃ for 2-3h to obtain modified polydopamine-coated basalt fiber.

[0006] In a preferred embodiment of the present invention, the ratio of tris(hydroxymethyl)aminomethane hydrochloride, deionized water, basalt fiber and dopamine hydrochloride in step A1 is 0.6-0.7g: 80-90mL: 3g: 1.5-1.7g.

[0007] In a preferred embodiment of the present invention, the basalt fibers in step A1 have an average diameter of 8 μm and an average length of 12 mm; the sodium hydroxide solution has a mass fraction of 20-30%.

[0008] In a preferred embodiment of the present invention, the ratio of polydopamine-coated basalt fiber, 3-aminopropyltriethoxysilane, triethylamine and anhydrous ethanol in step A2 is 3g:0.8-1.6g:2-3mL:50-60mL.

[0009] In a preferred embodiment of the present invention, the polyepoxy fluorinated compound is prepared by the following steps: Step B1: 2,2'-bis(trifluoromethyl)diaminobiphenyl, sodium hydroxide solution, and acetone are added to a three-necked flask equipped with a stirrer and a thermometer. The mixture is stirred for 20-30 minutes at a temperature of 20-25°C and a stirring rate of 200-300 r / min. Then, 6-bromo-1-hexene is added, and the mixture is heated to 50-60°C and stirred for another 8-10 hours. After the reaction is completed, the reaction product is cooled to room temperature, and the solvent is removed by rotary evaporation. The product is then poured into carbon tetrachloride, washed 2-3 times successively with saturated sodium bicarbonate solution and distilled water, dried with anhydrous sodium sulfate, and then vacuum-sealed. Step B2: The polyene-containing fluorine compound and dichloromethane are added to a three-necked flask equipped with a stirrer and thermometer. The mixture is stirred for 20-30 min at a temperature of 20-25℃ and a stirring rate of 200-300 r / min. Then, m-chloroperoxybenzoic acid is added and the mixture is heated to 40-45℃ and stirred for another 20-30 h. After the reaction is completed, the product is cooled to room temperature and then filtered under vacuum. The filtrate is washed 2-3 times successively with saturated sodium sulfite solution, saturated sodium bicarbonate solution and sodium chloride solution. Then, it is dried with anhydrous sodium sulfate and filtered under vacuum. The filtrate is then evaporated under vacuum to remove the solvent, yielding a polyepoxy-containing fluorine compound.

[0010] In a preferred embodiment of the present invention, the ratio of 2,2'-bis(trifluoromethyl)diaminobiphenyl, sodium hydroxide solution, acetone and 6-bromo-1-hexene in step B1 is 10 mmol: 20-30 mL: 40-50 mL: 45-50 mmol.

[0011] In a preferred embodiment of the present invention, the sodium hydroxide solution in step B1 has a mass fraction of 40-50%.

[0012] In a preferred embodiment of the present invention, the ratio of the polyene-containing fluorinated compound, dichloromethane, and m-chloroperoxybenzoic acid in step B2 is 10 mmol: 80-90 mL: 60-70 mmol.

[0013] In a preferred embodiment of the present invention, the sodium chloride solution in step B2 has a mass fraction of 3-5%.

[0014] Secondly, this application provides a method for preparing fiber-reinforced ultra-high performance concrete poles, which is used to prepare the fiber-reinforced ultra-high performance concrete poles described in the second aspect, including the following steps: Step 1: Weigh out 60-70 parts of cement, 75-80 parts of coarse aggregate, 50-55 parts of fine aggregate, 10-16 parts of nano-silica, 2-3 parts of water-reducing agent, 1.5-8.5 parts of modified polydopamine-coated basalt fiber, 1-7 parts of polyepoxy fluorinated compound, and 25-30 parts of water according to the following weight, and set aside; Step 2: Mix cement, coarse aggregate, fine aggregate, and nano-silica evenly. Then add water-reducing agent, modified polydopamine-coated basalt fiber, polyepoxy fluorinated compound, and water, and continue mixing evenly to obtain a mixture. Step 3: Pour the mixture into the steel mold of the pole, vibrate to compact it, and then demold after curing at room temperature for 24 hours. Then transfer it to a steam curing chamber and cure it for 48 hours at a temperature of 80-90℃ and a humidity of 95-97%, followed by natural curing for 28 days to obtain fiber-reinforced ultra-high performance concrete poles.

[0015] In a preferred embodiment of the present invention, the cement is PO·42.5 ordinary Portland cement.

[0016] In a preferred embodiment of the present invention, the coarse aggregate is limestone crushed stone with an average particle size of 10 mm.

[0017] In a preferred embodiment of the present invention, the fine aggregate is natural river sand with a particle size ≤ 0.5 mm.

[0018] In a preferred embodiment of the present invention, the average particle size of the nano-silica is 20 nm.

[0019] In a preferred embodiment of the present invention, the water-reducing agent is an FDN-A naphthalene-based high-efficiency water-reducing agent.

[0020] The beneficial effects of this invention are as follows: This invention provides a fiber-reinforced ultra-high performance concrete pole and its preparation method. The method involves uniformly mixing cement, coarse aggregate, fine aggregate, and nano-silica, then adding a water-reducing agent, modified polydopamine-coated basalt fiber, a polyepoxy fluorinated compound, and water, and continuing to mix until a mixture is obtained. This mixture is then injected into a pole mold, vibrated to compact it, cured at room temperature, demolded, and subsequently cured to obtain the fiber-reinforced ultra-high performance concrete pole. This preparation method, by adding modified polydopamine-coated basalt fiber and a polyepoxy fluorinated compound to the pole, significantly improves the pole's waterproof and water-resistant properties and mechanical properties, greatly enhancing its overall performance and significantly extending its service life in harsh environments. This ensures the long-term reliability and safety of the pole, meeting the usage requirements of various harsh environments and engineering scenarios, and promoting the high-quality development of power engineering construction.

[0021] In the process of preparing fiber-reinforced ultra-high performance concrete poles, a modified polydopamine-coated basalt fiber was first prepared. The basalt fiber was used as a core to form a polydopamine coating on its surface, resulting in polydopamine-coated basalt fiber. Then, the amino groups on 3-aminopropyltriethoxysilane reacted with the quinone groups on the polydopamine-coated basalt fiber, introducing a large amount of siloxane, thus obtaining the modified polydopamine-coated basalt fiber. The basalt fiber itself possesses excellent mechanical properties. After polydopamine coating, it can be uniformly dispersed in the concrete matrix, effectively transferring stress, inhibiting the generation and propagation of microcracks, and significantly improving the mechanical properties of the pole. Furthermore, the polydopamine molecule contains a large number of amino and hydroxyl groups, as well as grafted siloxanes, which can chemically react with other components in the concrete, enhancing interfacial bonding and effectively protecting the fiber from erosion during concrete hydration and curing.

[0022] In the process of preparing fiber-reinforced ultra-high performance concrete poles, a polyepoxy fluorinated compound was also prepared. This was achieved by reacting the amino group on 2,2'-bis(trifluoromethyl)diaminobiphenyl with the bromine atom on 6-bromo-1-hexene, introducing a large number of alkenyl groups to obtain a polyepoxy fluorinated compound. Subsequently, the alkenyl groups on the polyepoxy fluorinated compound were oxidized to epoxy groups using m-chloroperoxybenzoic acid, yielding the polyepoxy fluorinated compound. This polyepoxy fluorinated compound molecule contains multiple active epoxy groups, which can undergo ring-opening cross-linking reactions with other components in the concrete to form a three-dimensional dense cross-linked network. This network fills the capillary channels inside the concrete, reducing porosity and improving the density and mechanical strength of the concrete. Simultaneously, the cross-linked network can alleviate stress concentration, absorb fracture energy, improve material toughness, and prevent brittle fracture. Furthermore, the large number of fluorine atoms can form a hydrophobic layer inside the concrete, significantly reducing the surface energy of the material and hindering the erosion of water, acids, alkalis, and other corrosive media, thus improving the corrosion resistance of the pole. This results in a significant improvement in the waterproof and water-resistant properties and mechanical properties of the pole. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention. Embodiment 1:

[0024] This embodiment describes a method for preparing fiber-reinforced ultra-high performance concrete poles, comprising the following steps: Step S1: 0.6g of tris(hydroxymethyl)aminomethane hydrochloride and 80mL of deionized water are added to a three-necked flask equipped with a stirrer and thermometer. The mixture is stirred for 10min at 20℃ and a stirring rate of 200r / min. Then, the pH is adjusted to 8.5 with a 20% sodium hydroxide solution. 3g of basalt fiber with an average diameter of 8μm and an average length of 12mm and 1.5g of dopamine hydrochloride are added, and the mixture is stirred for another 20h. After the reaction is complete, the reaction product is vacuum filtered. The filter cake is washed twice with saturated sodium bicarbonate solution and distilled water, and then placed in a vacuum drying oven and dried at 50℃ for 4h to obtain polydopamine-coated basalt fiber; Step S2: 3g of polydopamine-coated basalt fiber and 0.8 g of 3-aminopropyltriethoxysilane, 2 mL of triethylamine, and 50 mL of anhydrous ethanol were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred at 20 °C and a stirring rate of 200 r / min for 10 min, then heated to 60 °C and stirred for another 15 h. After the reaction was completed, the product was cooled to room temperature, centrifuged, and the precipitate was washed twice with distilled water. The precipitate was then placed in a vacuum drying oven and dried at 70 °C for 2 h to obtain modified polydopamine-coated basalt fibers. Step S3: 10 mmol of 2,2 '-Di(trifluoromethyl)diaminobiphenyl, 20 mL of 40% sodium hydroxide solution, and 40 mL of acetone were added to a three-necked flask equipped with a stirrer and thermometer. The mixture was stirred at 20 °C and a stirring rate of 200 r / min for 20 min. Then, 45 mmol of 6-bromo-1-hexene was added, and the mixture was heated to 50 °C and stirred for another 8 h. After the reaction was completed, the product was cooled to room temperature, and the solvent was removed by rotary evaporation. The product was then poured into carbon tetrachloride and washed twice, successively with saturated sodium bicarbonate solution and distilled water, and finally with anhydrous sulfuric acid. Sodium was dried, then vacuum filtered, and the solvent was removed by rotary evaporation of the filtrate to obtain a polyene-containing fluorinated compound; Step S4: 10 mmol of the polyene-containing fluorinated compound and 80 mL of dichloromethane were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred for 20 min at 20 °C and a stirring rate of 200 r / min. Then, 60 mmol of m-chloroperoxybenzoic acid was added, and the mixture was heated to 40 °C and stirred for another 20 h. After the reaction was completed, the product was cooled to room temperature and then vacuum filtered. The filtrate was then filtered sequentially with saturated sodium sulfite solution and saturated sodium bicarbonate solution. The mixture was washed twice with a 3% sodium chloride solution, dried with anhydrous sodium sulfate, and then vacuum filtered. The solvent was removed by rotary evaporation of the filtrate to obtain a polyepoxy-based fluorinated compound. Step S5: 60 parts by weight of cement, 75 parts by weight of coarse aggregate, 50 parts by weight of fine aggregate, 10 parts by weight of nano-silica, 2 parts by weight of water-reducing agent, 1.5 parts by weight of modified polydopamine-coated basalt fiber, 1 part by weight of polyepoxy-based fluorinated compound, and 25 parts by weight of water were weighed and set aside. The cement was PO·42.5 ordinary Portland cement; the coarse aggregate was limestone crushed stone with an average particle size of 10 mm; and the fine aggregate had a particle size ≤ 0 mm.5mm natural river sand; the average particle size of the nano-silica is 20nm; the water-reducing agent is FDN-A naphthalene-based high-efficiency water-reducing agent; Step S6: Cement, coarse aggregate, fine aggregate and nano-silica are mixed evenly, then water-reducing agent, modified polydopamine-coated basalt fiber, polyepoxy fluorinated compound and water are added and mixed evenly to obtain a mixture; Step S7: The mixture is injected into the pole steel mold, vibrated to compact, then cured at room temperature for 24h before demolding, then transferred to a steam curing chamber, cured at 80℃ and 95% humidity for 48h, then naturally cured for 28d to obtain fiber-reinforced ultra-high performance concrete pole. Example 2:

[0025] This embodiment describes a method for preparing a fiber-reinforced ultra-high performance concrete pole, comprising the following steps: Step S1: 0.65g of tris(hydroxymethyl)aminomethane hydrochloride and 85mL of deionized water are added to a three-necked flask equipped with a stirrer and a thermometer. The mixture is stirred and reacted for 12min at a temperature of 22℃ and a stirring rate of 250r / min. Then, the pH is adjusted to 8.5 with a 25% sodium hydroxide solution. Next, 3g of basalt fibers with an average diameter of 8μm and an average length of 12mm and 1.6g of dopamine hydrochloride are added, and the reaction is continued to be stirred for 25h. After the reaction is completed, the reaction product is vacuum filtered, and the filter cake is washed twice, successively with saturated sodium bicarbonate solution and distilled water. The basalt fiber was then placed in a vacuum drying oven and dried at 55°C for 4.5 h to obtain polydopamine-coated basalt fiber. Step S2: 3 g of polydopamine-coated basalt fiber, 1.2 g of 3-aminopropyltriethoxysilane, 2.5 mL of triethylamine, and 55 mL of anhydrous ethanol were added to a three-necked flask equipped with a stirrer and thermometer. The mixture was stirred at 22°C and a stirring rate of 250 r / min for 12 min. Then, the temperature was raised to 65°C and the stirring was continued for 18 h. After the reaction was completed, the reaction product was cooled to room temperature, centrifuged, and the precipitate was washed twice with distilled water. The precipitate was then placed in a vacuum drying oven and dried at 75°C for 2 hours.After 5 hours, modified polydopamine-coated basalt fibers were obtained. Step S3: 10 mmol of 2,2'-bis(trifluoromethyl)diaminobiphenyl, 25 mL of 45% sodium hydroxide solution, and 45 mL of acetone were added to a three-necked flask equipped with a stirrer and thermometer. The mixture was stirred at 22°C and 250 r / min for 25 minutes. Then, 48 mmol of 6-bromo-1-hexene was added, and the mixture was heated to 55°C and stirred for another 9 hours. After the reaction, the product was cooled to room temperature, and the solvent was removed by rotary evaporation. The product was then poured into carbon tetrachloride and subsequently treated with saturated... The product was washed twice with sodium bicarbonate solution and distilled water, then dried with anhydrous sodium sulfate, and then vacuum filtered. The solvent was removed by rotary evaporation of the filtrate to obtain a polyene-containing fluorinated compound. Step S4: 10 mmol of the polyene-containing fluorinated compound and 85 mL of dichloromethane were added to a three-necked flask equipped with a stirrer and thermometer. The mixture was stirred for 25 min at 22 °C and a stirring rate of 250 r / min. Then, 65 mmol of m-chloroperoxybenzoic acid was added, and the mixture was heated to 42 °C and stirred for another 25 h. After the reaction was complete, the product was cooled to room temperature and then vacuum filtered. The filtrate was rinsed sequentially with saturated sodium sulfite solution. The mixture was washed twice with a saturated sodium bicarbonate solution and a 4% sodium chloride solution, then dried with anhydrous sodium sulfate, and then vacuum filtered. The filtrate was then evaporated by rotary evaporation to remove the solvent, yielding a polyepoxy-based fluorinated compound. Step S5: 65 parts by weight of cement, 78 parts by weight of coarse aggregate, 52 parts by weight of fine aggregate, 13 parts by weight of nano-silica, 2.5 parts by weight of water-reducing agent, 5 parts by weight of modified polydopamine-coated basalt fiber, 4 parts by weight of the polyepoxy-based fluorinated compound, and 28 parts by weight of water were weighed for later use. The cement was PO·42.5 ordinary silicate cement; the coarse aggregate was limestone crushed stone with an average particle size of 10 mm; the fine aggregate was fine aggregate with a particle size ≤0.5 mm. Natural river sand; the average particle size of the nano-silica is 20nm; the water-reducing agent is FDN-A naphthalene-based high-efficiency water-reducing agent; Step S6: Cement, coarse aggregate, fine aggregate and nano-silica are mixed evenly, then water-reducing agent, modified polydopamine-coated basalt fiber, polyepoxy fluorinated compound and water are added and mixed evenly to obtain a mixture; Step S7: The mixture is poured into the steel mold of the pole, vibrated to compact, then cured at room temperature for 24h before demolding, then transferred to a steam curing chamber, cured at 85℃ and 96% humidity for 48h, then naturally cured for 28d to obtain fiber-reinforced ultra-high performance concrete pole. Example 3:

[0026] This embodiment describes a method for preparing fiber-reinforced ultra-high performance concrete poles, comprising the following steps: Step S1: 0.7g of tris(hydroxymethyl)aminomethane hydrochloride and 90mL of deionized water are added to a three-necked flask equipped with a stirrer and thermometer. The mixture is stirred for 15 minutes at 25°C and a stirring rate of 300r / min. Then, the pH is adjusted to 8.5 with a 30% sodium hydroxide solution. 3g of basalt fiber with an average diameter of 8μm and an average length of 12mm and 1.7g of dopamine hydrochloride are added, and the mixture is stirred for another 30 hours. After the reaction is complete, the reaction product is vacuum filtered. The filter cake is washed three times with saturated sodium bicarbonate solution and distilled water, and then placed in a vacuum drying oven and dried at 60°C for 5 hours to obtain polydopamine-coated basalt fiber. Step S2: 3g of polydopamine-coated basalt fiber and 1.7g of dopamine hydrochloride are added to the basalt fiber.6 g of 3-aminopropyltriethoxysilane, 3 mL of triethylamine, and 60 mL of anhydrous ethanol were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred at 25 °C and a stirring rate of 300 r / min for 15 min, then heated to 70 °C and stirred for another 20 h. After the reaction was completed, the product was cooled to room temperature, centrifuged, and the precipitate was washed three times with distilled water. The precipitate was then placed in a vacuum drying oven and dried at 80 °C for 3 h to obtain modified polydopamine-coated basalt fibers; Step S3: 10 mmol of 2,2' 6-Di(trifluoromethyl)diaminobiphenyl, 30 mL of 50% sodium hydroxide solution, and 50 mL of acetone were added to a three-necked flask equipped with a stirrer and thermometer. The mixture was stirred at 25 °C and a stirring rate of 300 rpm for 30 min. Then, 50 mmol of 6-bromo-1-hexene was added, and the mixture was heated to 60 °C and stirred for another 10 h. After the reaction was completed, the product was cooled to room temperature, and the solvent was removed by rotary evaporation. The product was then poured into carbon tetrachloride and washed three times, successively with saturated sodium bicarbonate solution and distilled water, and finally with anhydrous sulfuric acid. Sodium was dried, then vacuum filtered, and the solvent was removed by rotary evaporation of the filtrate to obtain a polyene-containing fluorinated compound; Step S4: 10 mmol of the polyene-containing fluorinated compound and 90 mL of dichloromethane were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred for 30 min at 25 °C and a stirring rate of 300 r / min. Then, 70 mmol of m-chloroperoxybenzoic acid was added, and the mixture was heated to 45 °C and stirred for another 30 h. After the reaction was completed, the reaction product was cooled to room temperature and then vacuum filtered. The filtrate was then filtered sequentially with saturated sodium sulfite solution and saturated sodium bicarbonate solution. The mixture was washed three times with a 5% sodium chloride solution, dried with anhydrous sodium sulfate, and then vacuum filtered. The solvent was removed by rotary evaporation of the filtrate to obtain a polyepoxy-based fluorinated compound. Step S5: Weigh out 70 parts by weight of cement, 80 parts by weight of coarse aggregate, 55 parts by weight of fine aggregate, 16 parts by weight of nano-silica, 3 parts by weight of water-reducing agent, 8.5 parts by weight of modified polydopamine-coated basalt fiber, 7 parts by weight of polyepoxy-based fluorinated compound, and 30 parts by weight for later use. The cement is PO·42.5 ordinary Portland cement; the coarse aggregate is limestone crushed stone with an average particle size of 10 mm; the fine aggregate has a particle size ≤ 0 mm.The process involves using 5mm natural river sand; the average particle size of the nano-silica is 20nm; the water-reducing agent is FDN-A naphthalene-based high-efficiency water-reducing agent; Step S6: Cement, coarse aggregate, fine aggregate, and nano-silica are mixed evenly, then the water-reducing agent, modified polydopamine-coated basalt fiber, polyepoxy fluorinated compound, and water are added and mixed evenly to obtain a mixture; Step S7: The mixture is poured into a steel mold for the utility pole, vibrated to compact it, and then cured at room temperature for 24 hours before demolding. The pole is then transferred to a steam curing chamber and cured at 90℃ and 97% humidity for 48 hours, followed by natural curing for 28 days to obtain a fiber-reinforced ultra-high performance concrete utility pole.

[0027] Comparative Example 1: This comparative example is a method for preparing a fiber-reinforced ultra-high performance concrete pole, comprising the following steps: Step S1: Weigh 70 parts by weight of cement, 80 parts by weight of coarse aggregate, 55 parts by weight of fine aggregate, 16 parts by weight of nano-silica, 3 parts by weight of water-reducing agent, and 30 parts by weight for later use; the cement is PO·42.5 ordinary Portland cement; the coarse aggregate is limestone crushed stone with an average particle size of 10 mm; the fine aggregate is natural river sand with a particle size ≤0.5 mm; the average particle size of the nano-silica is... 20nm; The water-reducing agent is FDN-A naphthalene-based high-efficiency water-reducing agent; Step S2: Cement, coarse aggregate, fine aggregate and nano silica are mixed evenly, then water-reducing agent and water are added and mixed evenly to obtain a mixture; Step S3: The mixture is injected into the steel mold of the pole, vibrated to compact, then cured at room temperature for 24 hours and demolded, then transferred to a steam curing chamber and cured at 90℃ and 97% humidity for 48 hours, then naturally cured for 28 days to obtain fiber-reinforced ultra-high performance concrete pole.

[0028] Comparative Example 2: This comparative example is a method for preparing a fiber-reinforced ultra-high performance concrete pole, including the following steps: Step S1: 0.7g of tris(hydroxymethyl)aminomethane hydrochloride and 90mL of deionized water are added to a three-necked flask equipped with a stirrer and a thermometer. The mixture is stirred and reacted for 15min at a temperature of 25℃ and a stirring rate of 300r / min. Then, the pH is adjusted to 8.5 with a 30% sodium hydroxide solution. Next, 3g of basalt fiber with an average diameter of 8μm and an average length of 12mm and 1.7g of dopamine hydrochloride are added, and the mixture is stirred and reacted for another 30h. The reaction is then completed. The reaction product was then vacuum filtered, and the filter cake was washed three times successively with saturated sodium bicarbonate solution and distilled water. It was then placed in a vacuum drying oven and dried at 60℃ for 5 hours to obtain polydopamine-coated basalt fibers. Step S2: 3g of polydopamine-coated basalt fibers, 1.6g of 3-aminopropyltriethoxysilane, 3mL of triethylamine, and 60mL of anhydrous ethanol were added to a three-necked flask equipped with a stirrer and thermometer. The mixture was stirred at 25℃ and a stirring rate of 300r / min for 15 minutes, then the temperature was raised to 70℃ and the stirring continued for 20 hours. After the reaction is complete, the product is cooled to room temperature, then centrifuged. The precipitate is washed three times with distilled water and then placed in a vacuum drying oven at 80°C for 3 hours to obtain modified polydopamine-coated basalt fiber. Step S3: Weigh out 70 parts by weight of cement, 80 parts by weight of coarse aggregate, 55 parts by weight of fine aggregate, 16 parts by weight of nano-silica, 3 parts by weight of water-reducing agent, 8.5 parts by weight of modified polydopamine-coated basalt fiber, and 30 parts by weight for later use. The cement is PO·42.5 ordinary Portland cement; the coarse aggregate is limestone crushed stone with an average particle size of 10 mm; the fine aggregate has a particle size ≤0.5 mm. The material is natural river sand; the average particle size of the nano-silica is 20 nm; the water-reducing agent is FDN-A naphthalene-based high-efficiency water-reducing agent; Step S4: Cement, coarse aggregate, fine aggregate and nano-silica are mixed evenly, then water-reducing agent, modified polydopamine-coated basalt fiber and water are added and mixed evenly to obtain a mixture; Step S5: The mixture is injected into the steel mold of the pole, vibrated to compact, then cured at room temperature for 24 h and demolded, then transferred to a steam curing chamber and cured at 90℃ and 97% humidity for 48 h, then naturally cured for 28 days to obtain fiber-reinforced ultra-high performance concrete pole.

[0029] Comparative Example 3: This comparative example is a method for preparing a fiber-reinforced ultra-high performance concrete pole, comprising the following steps: Step S1: 10 mmol of 2,2'-bis(trifluoromethyl)diaminobiphenyl, 30 mL of 50% sodium hydroxide solution, and 50 mL of acetone were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred and reacted for 30 min at 25 °C and a stirring rate of 300 r / min. Then, 50 mmol of 6-bromo-1-hexene was added, and the mixture was heated to 60 °C and stirred for another 10 h. After the reaction was completed, the reaction product was cooled to room temperature and then rotary evaporated. Remove the solvent, then pour into carbon tetrachloride, wash three times successively with saturated sodium bicarbonate solution and distilled water, dry with anhydrous sodium sulfate, and then filter under vacuum. The filtrate is then evaporated by rotary evaporation to remove the solvent, yielding a polyene-containing fluorinated compound. Step S2: Add 10 mmol of the polyene-containing fluorinated compound and 90 mL of dichloromethane to a three-necked flask equipped with a stirrer and thermometer. Stir the reaction at 25°C and a stirring rate of 300 r / min for 30 min. Then add 70 mmol of m-chloroperoxybenzoic acid and continue stirring at 45°C for 30 h. After the reaction is complete, cool the reaction product. The solution was cooled to room temperature, then vacuum filtered. The filtrate was washed three times successively with saturated sodium sulfite solution, saturated sodium bicarbonate solution, and 5% sodium chloride solution. It was then dried with anhydrous sodium sulfate, vacuum filtered again, and the solvent was removed by rotary evaporation to obtain a polyepoxy-based fluorinated compound. Step S3: 70 parts by weight of cement, 80 parts by weight of coarse aggregate, 55 parts by weight of fine aggregate, 16 parts by weight of nano-silica, 3 parts by weight of water-reducing agent, 7 parts by weight of polyepoxy-based fluorinated compound, and 30 parts by weight were weighed and set aside. The cement was PO·42.5 ordinary Portland cement; the coarse aggregate was limestone crushed stone with an average particle size of 10 mm; the fine aggregate... The material is natural river sand with a particle size ≤ 0.5 mm; the average particle size of the nano-silica is 20 nm; the water-reducing agent is FDN-A naphthalene-based high-efficiency water-reducing agent; Step S4: Cement, coarse aggregate, fine aggregate and nano-silica are mixed evenly, then water-reducing agent, polyepoxy fluorinated compound and water are added and mixed evenly to obtain a mixture; Step S5: The mixture is injected into the steel mold of the pole, vibrated to compact, then cured at room temperature for 24 h and demolded, then transferred to a steam curing chamber and cured at 90℃ and 97% humidity for 48 h, then naturally cured for 28 days to obtain fiber-reinforced ultra-high performance concrete pole.

[0030] Comparative Example 4: This comparative example is a method for preparing a fiber-reinforced ultra-high performance concrete pole, comprising the following steps: Step S1: Weigh out 70 parts by weight of cement, 80 parts by weight of coarse aggregate, 55 parts by weight of fine aggregate, 16 parts by weight of nano-silica, 3 parts by weight of water-reducing agent, 8.5 parts by weight of basalt fiber, 7 parts by weight of polyepoxy fluorinated compound, and 30 parts by weight for later use; the cement is PO·42.5 ordinary Portland cement; the coarse aggregate is limestone crushed stone with an average particle size of 10 mm; the fine aggregate is natural river sand with a particle size ≤0.5 mm; the average particle size of the nano-silica is 20 nm; the water-reducing agent is FDN-A. Naphthalene-based high-efficiency water-reducing agent; the basalt fiber has an average diameter of 8μm and an average length of 12mm; the epoxy resin is epoxy resin E-44; Step S2: Cement, coarse aggregate, fine aggregate and nano silica are mixed evenly, then water-reducing agent, basalt fiber, epoxy resin and water are added and mixed evenly to obtain a mixture; Step S3: The mixture is injected into the steel mold of the pole, vibrated to compact, then cured at room temperature for 24h and demolded, then transferred to a steam curing chamber and cured at 90℃ and 97% humidity for 48h, then naturally cured for 28d to obtain fiber-reinforced ultra-high performance concrete pole.

[0031] For performance testing, test samples of 40mm × 40mm × 160mm were cut from the same location of the fiber-reinforced ultra-high performance concrete poles of Examples 1-3 and Comparative Examples 1-4. Water droplets were used as test droplets to measure the water droplet contact angle. Then, the flexural strength and compressive strength were tested according to GB / T 50081-2019. The test results are shown in the table below:

[0032] Referring to the data in the table above, and based on the comparison between Examples 1-3 and Comparative Examples 1-4, it can be seen that adding modified polydopamine-coated basalt fibers and polyepoxy fluorinated compounds can significantly improve the water droplet contact angle, flexural strength, and compressive strength of concrete poles, indicating that the concrete poles have excellent waterproof and water-resistant properties and mechanical properties.

[0033] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0034] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in this application, they should all fall within the protection scope of the present invention.

Claims

1. A fiber-reinforced ultra-high performance concrete pole, characterized in that, The product comprises the following components by weight: 60-70 parts cement, 75-80 parts coarse aggregate, 50-55 parts fine aggregate, 10-16 parts nano-silica, 2-3 parts water-reducing agent, 1.5-8.5 parts modified polydopamine-coated basalt fiber, 1-7 parts polyepoxy fluorinated compound, and 25-30 parts water; wherein the modified polydopamine-coated basalt fiber is prepared by the following steps: Step A1: Tris(hydroxymethyl)aminomethane hydrochloride and deionized water are stirred and reacted... The pH was then adjusted with sodium hydroxide solution, followed by the addition of basalt fiber and dopamine hydrochloride, and the reaction was continued with stirring. After the reaction was completed, the reaction product was vacuum filtered, and the filter cake was washed and dried to obtain polydopamine-coated basalt fiber. Step A2: Polydopamine-coated basalt fiber, 3-aminopropyltriethoxysilane, triethylamine and anhydrous ethanol were stirred and reacted. After the reaction was completed, the reaction product was cooled, centrifuged, and the precipitate was washed and dried to obtain modified polydopamine-coated basalt fiber.

2. The fiber-reinforced ultra-high performance concrete pole according to claim 1, characterized in that, The ratio of the amounts of tris(hydroxymethyl)aminomethane hydrochloride, deionized water, basalt fiber and dopamine hydrochloride in step A1 is 0.6-0.7g: 80-90mL: 3g: 1.5-1.7g.

3. The fiber-reinforced ultra-high performance concrete pole according to claim 1, characterized in that, The basalt fibers in step A1 have an average diameter of 8 μm and an average length of 12 mm; the sodium hydroxide solution has a mass fraction of 20-30%.

4. The fiber-reinforced ultra-high performance concrete pole according to claim 1, characterized in that, In step A2, the ratio of polydopamine-coated basalt fiber, 3-aminopropyltriethoxysilane, triethylamine, and anhydrous ethanol is 3g:0.8-1.6g:2-3mL:50-60mL.

5. A fiber-reinforced ultra-high performance concrete pole according to claim 1, characterized in that, The polyepoxy fluorinated compound is prepared by the following steps: Step B1: 2,2'-bis(trifluoromethyl)diaminobiphenyl, sodium hydroxide solution and acetone are stirred and reacted, then 6-bromo-1-hexene is added and the reaction is continued with stirring. After the reaction is completed, the reaction product is cooled, then evaporated by rotary evaporation, then poured into carbon tetrachloride, then washed and dried, then vacuum filtered, and the filtrate is evaporated by rotary evaporation to obtain the polyepoxy fluorinated compound; Step B2: The polyepoxy fluorinated compound and dichloromethane are stirred and reacted, then m-chloroperoxybenzoic acid is added and the reaction is continued with stirring. After the reaction is completed, the reaction product is cooled, then vacuum filtered, the filtrate is washed and dried, then vacuum filtered, and the filtrate is evaporated by rotary evaporation to obtain the polyepoxy fluorinated compound.

6. A fiber-reinforced ultra-high performance concrete pole according to claim 5, characterized in that, The ratio of 2,2'-bis(trifluoromethyl)diaminobiphenyl, sodium hydroxide solution, acetone and 6-bromo-1-hexene in step B1 is 10 mmol: 20-30 mL: 40-50 mL: 45-50 mmol.

7. A fiber-reinforced ultra-high performance concrete pole according to claim 5, characterized in that, The sodium hydroxide solution in step B1 has a mass fraction of 40-50%.

8. A fiber-reinforced ultra-high performance concrete pole according to claim 5, characterized in that, The ratio of the polyene-containing fluorinated compound, dichloromethane, and m-chloroperoxybenzoic acid used in step B2 is 10 mmol: 80-90 mL: 60-70 mmol.

9. A method for preparing a fiber-reinforced ultra-high performance concrete pole, characterized in that, The method for preparing the fiber-reinforced ultra-high performance concrete pole according to any one of claims 1-8 includes the following steps: Step 1: Weigh out 60-70 parts of cement, 75-80 parts of coarse aggregate, 50-55 parts of fine aggregate, 10-16 parts of nano-silica, 2-3 parts of water-reducing agent, 1.5-8.5 parts of modified polydopamine-coated basalt fiber, 1-7 parts of polyepoxy fluorinated compound, and 25-30 parts of water according to weight, and set aside; Step 2: Mix cement, coarse aggregate, fine aggregate, and water... Aggregates and nano-silica are mixed evenly, then water-reducing agent, modified polydopamine-coated basalt fiber, polyepoxy fluorinated compound and water are added and mixed evenly to obtain a mixture; Step 3: The mixture is injected into the steel mold of the pole, vibrated to compact it, and then cured at room temperature for 24 hours before demolding. Then it is transferred to a steam curing chamber and cured for 48 hours at a temperature of 80-90℃ and a humidity of 95-97%, followed by natural curing for 28 days to obtain fiber-reinforced ultra-high performance concrete poles.

10. The method for preparing a fiber-reinforced ultra-high performance concrete pole according to claim 9, characterized in that, The cement is PO·42.5 ordinary Portland cement; the coarse aggregate is limestone crushed stone with an average particle size of 10mm; the fine aggregate is natural river sand with a particle size ≤0.5mm; the nano silica has an average particle size of 20nm; and the water-reducing agent is FDN-A naphthalene-based high-efficiency water-reducing agent.

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