Anti-corrosion concrete curb and preparation method thereof

Abstract

The invention belongs to the technical field of road engineering materials, and particularly relates to an anti-corrosion concrete curb and a preparation method thereof. The anti-corrosion concrete curb is prepared from the following components in parts by mass: 1000 to 1200 parts of coarse aggregate, 650 to 700 parts of fine aggregate, 320 to 350 parts of cement, 60 to 80 parts of fly ash, 80 to 100 parts of superfine slag powder, 20 to 30 parts of silica fume, 10 to 20 parts of metakaolin, 1 to 2 parts of modified polypropylene fiber, 5 to 10 parts of a water reducing agent, 0.05 to 0.15 part of an air entraining agent and 130 to 150 parts of water, the anti-corrosion concrete curb provided by the invention has excellent strength and corrosion resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of road engineering materials, and particularly relates to an anti-corrosion concrete curbstone and a preparation method thereof. Background Art

[0002] Curbstones are road boundary stones that not only intercept and collect rainwater and beautify the road surface, but also provide good protection for the road edge. Traditional concrete curbstones are prone to fractures and damage due to the corrosive factors of the operating environment. Currently, extruded curbstones are mainly composed of cementitious materials and fine aggregates, and auxiliary cementitious materials with certain reactivity, such as fly ash. However, the inventors have found that the main problem with existing concrete curbstones is that the traditional formula has low strength and poor resistance to natural corrosion such as salt frost, acid and alkali, and impact. Some formulas increase strength by adding fibers, but most fibers have poor affinity with matrices such as cement, resulting in a significant decrease in impermeability. Therefore, concrete curbstones prepared by existing technologies are easily corroded and damaged. Summary of the Invention

[0003] The purpose of the present invention is to provide an anti-corrosion concrete curbstone and a preparation method thereof, so as to solve the problems existing in the prior art.

[0004] The present invention adopts a technical solution to achieve its purpose: an anti-corrosion concrete curbstone, comprising the following components in parts by mass: 1000-1200 parts of coarse aggregate, 650-700 parts of fine aggregate, 320-350 parts of cement, 60-80 parts of fly ash, 80-100 parts of slag powder, 20-30 parts of silica fume, 10-20 parts of metakaolin, 1-2 parts of modified polypropylene fiber, 5-10 parts of water reducer, 0.05-0.15 parts of air entraining agent, and 130-150 parts of water.

[0005] Furthermore, the coarse aggregate is high-strength crushed stone with a particle size of 5-15 mm, and the fine aggregate is machine-made sand with a fineness modulus of 2.6-3.0.

[0006] Furthermore, the water reducer is a polycarboxylic acid-based high-performance water reducer, and the air entraining agent is a special air entraining agent for polycarboxylic acid-based high-performance water reducer.

[0007] Furthermore, the length of the modified polypropylene fiber is controlled within the range of 10-20 mm.

[0008] Furthermore, the preparation method of the modified polypropylene fiber is:

[0009] (a) adding nano-silica to an ethanol aqueous solution having a volume fraction of 80-90%, stirring and dispersing the mixture, adding a silane coupling agent, reacting the mixture at a temperature of 70-80° C. for 6 h, and centrifuging and washing the mixture to obtain modified silica;

[0010] (b) adding modified silica, hydroxyethyl methacrylate, pentaerythritol triacrylate, and 2,2-dimethoxy-2-phenylacetophenone to N,N-dimethylformamide, irradiating the mixture with ultraviolet light for 40 minutes under nitrogen protection, washing the mixture by centrifugation, and drying the mixture to obtain grafted silica;

[0011] (c) A polypropylene matrix resin, grafted silica, an acrylic acid grafted polypropylene compatibilizer, a polycarboxylate ether, and an antioxidant are added to a twin-screw extruder to prepare a masterbatch, which is then melt-spun, post-treated, and wound and collected through a single-screw spinning machine to obtain modified polypropylene fibers.

[0012] Furthermore, the post-processing in step (c) comprises the following steps:

[0013] (1) soaking the fibers produced by the melt spinning process in an impregnation solution containing 0.1% by mass of polycarboxylate ether and 0.05% by mass of a silane coupling agent at a temperature of 50-55° C. for 30 seconds;

[0014] (2) The soaked fiber is subjected to primary stretching at a temperature of 10-30°C, with the stretching ratio controlled within the range of 1.6-2.0; then, the fiber is subjected to secondary stretching at a temperature of 105-115°C, with the stretching ratio controlled within the range of 2.0-2.4, and the total stretching ratio is controlled within the range of 3.6-4.2;

[0015] (3) The stretched fiber is relaxed in saturated steam at 100-110°C for 4-6 minutes.

[0016] Furthermore, in the step (a), the mass ratio of nano-silica to silane coupling agent is 5:2.

[0017] Furthermore, in the step (c), the mass ratio of the polypropylene matrix resin, the grafted silica, the acrylic acid grafted polypropylene compatibilizer, the polycarboxylate ether, and the antioxidant is 100:4:3:0.4:0.3.

[0018] Furthermore, a method for preparing an anti-corrosion concrete curbstone is characterized in that the coarse aggregate and fine aggregate are put into a mixer and dry-mixed for 15-30 seconds; then cement, fly ash, slag powder, silica fume, metakaolin, modified polypropylene fiber, water reducer, and air entraining agent are added and dry-mixed for 90-120 seconds; then water is added and wet-mixed for 90-120 seconds to obtain a mixture; the mixture is evenly poured into a mold coated with a release agent, vibrated to form, demolded, and subjected to standard maintenance to obtain an anti-corrosion concrete curbstone.

[0019] Furthermore, the vibration molding process is: using a vibration device at a frequency of 50-100 Hz and an amplitude of 0.5-1.0 mm, vibrating until the surface of the mixture is slurried and bubbles basically stop overflowing, then continuing to vibrate for 10 seconds, and then stopping vibration to smooth the surface.

[0020] The beneficial effects of the present invention are as follows: the anti-corrosion concrete curb prepared by the present invention is based on conventional cementitious materials such as cement and fly ash, and has been verified by a large number of experiments to add slag powder, silica fume, and metakaolin reinforcement materials. The slag powder and metakaolin can significantly improve the strength, density, and sulfate corrosion resistance of the concrete curb and can reduce the diffusion of chloride ions to exert long-term corrosion resistance. The silica fume can significantly reduce permeability and improve chemical corrosion resistance. The modified polypropylene fiber reinforcement material is used. The modified polypropylene fiber provided by the present invention has good affinity with the matrix, which prevents the problem that the traditional polypropylene fiber has poor affinity with the matrix, resulting in a decrease in the anti-permeability performance of the anti-corrosion concrete curb, effectively improves the strength and toughness of the concrete curb, and at the same time makes the concrete curb have excellent acid and alkali corrosion resistance, and can also significantly inhibit the plastic shrinkage cracks of the anti-corrosion concrete curb. DETAILED DESCRIPTION

[0021] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0022] Example 1

[0023] Preparation of modified polypropylene fiber

[0024] (a) 10 parts by mass of nano-silica were added to 80 parts by volume of an 80-90% ethanol aqueous solution, stirred and dispersed, and then 4 parts of a silane coupling agent (γ-methacryloxypropyltrimethoxysilane was used in this embodiment) was added. The mixture was reacted at 70-80° C. for 6 h, and then centrifuged and washed to obtain modified silica.

[0025] (b) adding 10 parts of modified silica, 2 parts of hydroxyethyl methacrylate, 1 part of pentaerythritol triacrylate, and 0.2 parts of 2,2-dimethoxy-2-phenylacetophenone to 40 parts of N,N-dimethylformamide, irradiating with ultraviolet light for 40 minutes under nitrogen protection, centrifuging, washing, and drying to obtain grafted silica;

[0026] (c) 100 parts of polypropylene matrix resin (spinning grade PP with a melt index of 20-35 g / 10 min is selected in this embodiment), 4 parts of grafted silica, 3 parts of acrylic acid grafted polypropylene compatibilizer (PP-g-AA compatibilizer of Lushan Chemical is used in this embodiment, with a grafting rate of 0.56%), 0.3 parts of polycarboxylate ether, 0.4 parts of antioxidant (Irganox The masterbatch is added into a twin-screw extruder to prepare a masterbatch (the temperature during the preparation process is controlled at 170-190° C.), and then the masterbatch is melt-spun through a single-screw spinning machine, the temperatures of zones 1-4 of the single-screw spinning machine are 175° C., 185° C., 190° C., and 180° C., and the spinning speed is 700 m / min. The fiber produced by the melt spinning process is immersed in an impregnation solution containing 0.1% by mass of polycarboxylate ether and 0.05% of a silane coupling agent at a temperature of 50-55° C. for 30 seconds; the immersed fiber is subjected to a primary stretching at a temperature of 10-30° C. with a stretching ratio controlled within the range of 1.6-2.0; then, the fiber is subjected to a secondary stretching at a temperature of 105-115° C. with a stretching ratio controlled within the range of 2.0-2.4, and a total stretching ratio controlled within the range of 3.6-4.2; the stretched fiber is relaxed in saturated steam at 100-110° C. for 4-6 minutes, and wound and collected to produce a modified polypropylene fiber.

[0027] Preparation of corrosion-resistant concrete curbstones

[0028] 1100 parts by mass of high-strength crushed stone (granite crushed stone is used in this embodiment) with a particle size of 5-15 mm and 680 parts of machine-made sand with a fineness modulus of 2.6-3.0 are put into a mixer and dry-mixed for 15-30 seconds; then 340 parts of ordinary Portland cement, 75 parts of fly ash, 95 parts of slag powder, 25 parts of silica fume, 16 parts of metakaolin, 1.8 parts of modified polypropylene fiber (the length of the modified polypropylene fiber is controlled within the range of 10-20 mm), and a water reducer (RHEOPLUS is used in this embodiment) are added. 410) 8 parts, air entraining agent (FA2280 is used in this embodiment) 0.1 part dry-mix for 90-120s; then 145 parts water is added and wet-mixed for 90-120s to obtain a mixture; the mixture is evenly poured into a mold coated with a release agent, and the mold is placed on a high-frequency vibration table and vibrated at a frequency of 50-100 Hz and an amplitude of 0.5-1.0 mm until the surface of the mixture is slurried and bubbles basically stop overflowing, and then the vibration is continued for 10 seconds, and then the vibration is stopped and the surface is smoothed, and then it is allowed to stand for 2-4 hours in an environment with a temperature of 15-25°C and a relative humidity of ≥90%, and then demolding and standard curing are carried out to obtain an anti-corrosion concrete curbstone.

[0029] Example 2

[0030] Preparation of modified polypropylene fiber

[0031] (a) 10 parts by mass of nano-silica were added to 80 parts by volume of an 80-90% ethanol aqueous solution, stirred and dispersed, and then 4 parts of a silane coupling agent (γ-methacryloxypropyltrimethoxysilane was used in this embodiment) was added. The mixture was reacted at 70-80° C. for 6 h, and then centrifuged and washed to obtain modified silica.

[0032] (b) adding 10 parts of modified silica, 2 parts of hydroxyethyl methacrylate, 1 part of pentaerythritol triacrylate, and 0.2 parts of 2,2-dimethoxy-2-phenylacetophenone to 40 parts of N,N-dimethylformamide, irradiating with ultraviolet light for 40 minutes under nitrogen protection, centrifuging, washing, and drying to obtain grafted silica;

[0033] (c) 100 parts of polypropylene matrix resin (spinning grade PP with a melt index of 20-35 g / 10 min is selected in this embodiment), 4 parts of grafted silica, 3 parts of acrylic acid grafted polypropylene compatibilizer (PP-g-AA compatibilizer of Lushan Chemical is used in this embodiment, with a grafting rate of 0.56%), 0.3 parts of polycarboxylate ether, 0.4 parts of antioxidant (Irganox The masterbatch is added into a twin-screw extruder to prepare a masterbatch (the temperature during the preparation process is controlled at 170-190° C.), and then the masterbatch is melt-spun through a single-screw spinning machine, the temperatures of zones 1-4 of the single-screw spinning machine are 175° C., 185° C., 190° C., and 180° C., and the spinning speed is 700 m / min. The fiber produced by the melt spinning process is immersed in an impregnation solution containing 0.1% by mass of polycarboxylate ether and 0.05% of a silane coupling agent at a temperature of 50-55° C. for 30 seconds; the immersed fiber is subjected to a primary stretching at a temperature of 10-30° C. with a stretching ratio controlled within the range of 1.6-2.0; then, the fiber is subjected to a secondary stretching at a temperature of 105-115° C. with a stretching ratio controlled within the range of 2.0-2.4, and a total stretching ratio controlled within the range of 3.6-4.2; the stretched fiber is relaxed in saturated steam at 100-110° C. for 4-6 minutes, and wound and collected to produce a modified polypropylene fiber.

[0034] Preparation of corrosion-resistant concrete curbstones

[0035] 1000 parts by mass of high-strength crushed stone (granite crushed stone is used in this embodiment) with a particle size of 5-15 mm and 650 parts of machine-made sand with a fineness modulus of 2.6-3.0 are put into a mixer and dry-mixed for 15-30 seconds; then 320 parts of ordinary Portland cement, 60 parts of fly ash, 80 parts of slag powder, 20 parts of silica fume, 10 parts of metakaolin, 1 part of modified polypropylene fiber (the length of the modified polypropylene fiber is controlled within the range of 10-20 mm), and a water reducer (RHEOPLUS is used in this embodiment) are added. 410) 5 parts, air entraining agent (FA2280 is used in this embodiment) 0.05 parts) and dry-mix for 90-120s; then, 130 parts of water are added and wet-mixed for 90-120s to obtain a mixture; the mixture is evenly poured into a mold coated with a release agent, and the mold is placed on a high-frequency vibration table and vibrated at a frequency of 50-100 Hz and an amplitude of 0.5-1.0 mm until the surface of the mixture is slurried and bubbles basically stop overflowing, and then the vibration is continued for 10 seconds, and then the vibration is stopped and the surface is smoothed, and then it is allowed to stand for 2-4 hours in an environment with a temperature of 15-25°C and a relative humidity of ≥90%, and then demolding and standard curing are carried out to obtain an anti-corrosion concrete curbstone.

[0036] Example 3

[0037] Preparation of modified polypropylene fiber

[0038] (a) 10 parts by mass of nano-silica were added to 80 parts by volume of an 80-90% ethanol aqueous solution, stirred and dispersed, and then 4 parts of a silane coupling agent (γ-methacryloxypropyltrimethoxysilane was used in this embodiment) was added. The mixture was reacted at 70-80° C. for 6 h, and then centrifuged and washed to obtain modified silica.

[0039] (b) adding 10 parts of modified silica, 2 parts of hydroxyethyl methacrylate, 1 part of pentaerythritol triacrylate, and 0.2 parts of 2,2-dimethoxy-2-phenylacetophenone to 40 parts of N,N-dimethylformamide, irradiating with ultraviolet light for 40 minutes under nitrogen protection, centrifuging, washing, and drying to obtain grafted silica;

[0040] (c) 100 parts of polypropylene matrix resin (spinning grade PP with a melt index of 20-35 g / 10 min is selected in this embodiment), 4 parts of grafted silica, 3 parts of acrylic acid grafted polypropylene compatibilizer (PP-g-AA compatibilizer of Lushan Chemical is used in this embodiment, with a grafting rate of 0.56%), 0.3 parts of polycarboxylate ether, 0.4 parts of antioxidant (Irganox The masterbatch is added into a twin-screw extruder to prepare a masterbatch (the temperature during the preparation process is controlled at 170-190° C.), and then the masterbatch is melt-spun through a single-screw spinning machine, the temperatures of zones 1-4 of the single-screw spinning machine are 175° C., 185° C., 190° C., and 180° C., and the spinning speed is 700 m / min. The fiber produced by the melt spinning process is immersed in an impregnation solution containing 0.1% by mass of polycarboxylate ether and 0.05% of a silane coupling agent at a temperature of 50-55° C. for 30 seconds; the immersed fiber is subjected to a primary stretching at a temperature of 10-30° C. with a stretching ratio controlled within the range of 1.6-2.0; then, the fiber is subjected to a secondary stretching at a temperature of 105-115° C. with a stretching ratio controlled within the range of 2.0-2.4, and a total stretching ratio controlled within the range of 3.6-4.2; the stretched fiber is relaxed in saturated steam at 100-110° C. for 4-6 minutes, and wound and collected to produce a modified polypropylene fiber.

[0041] Preparation of corrosion-resistant concrete curbstones

[0042] 1200 parts by mass of high-strength crushed stone (granite crushed stone is used in this embodiment) with a particle size of 5-15 mm and 700 parts of machine-made sand with a fineness modulus of 2.6-3.0 are put into a mixer and dry-mixed for 15-30 seconds; then 350 parts of ordinary Portland cement, 80 parts of fly ash, 100 parts of slag powder, 30 parts of silica fume, 20 parts of metakaolin, 2 parts of modified polypropylene fiber (the length of the modified polypropylene fiber is controlled within the range of 10-20 mm), and a water reducer (RHEOPLUS is used in this embodiment) are added. 410) 10 parts, air entraining agent (FA2280 is used in this embodiment) 0.15 parts dry-mixing for 90-120s; then, 150 parts water is added and wet-mixing is carried out for 90-120s to obtain a mixture; the mixture is evenly poured into a mold coated with a release agent, and the mold is placed on a high-frequency vibration table and vibrated at a frequency of 50-100 Hz and an amplitude of 0.5-1.0 mm until the surface of the mixture is slurried and bubbles basically stop overflowing, and then the vibration is continued for 10 seconds, and then the vibration is stopped and the surface is smoothed, and then it is allowed to stand for 2-4 hours in an environment with a temperature of 15-25°C and a relative humidity of ≥90%, and then demolding and standard curing are carried out to obtain an anti-corrosion concrete curbstone.

[0043] Example 4

[0044] Preparation of modified polypropylene fiber

[0045] (a) 10 parts by mass of nano-silica were added to 80 parts by volume of an 80-90% ethanol aqueous solution, stirred and dispersed, and then 4 parts of a silane coupling agent (γ-methacryloxypropyltrimethoxysilane was used in this embodiment) was added. The mixture was reacted at 70-80° C. for 6 h, and then centrifuged and washed to obtain modified silica.

[0046] (b) adding 10 parts of modified silica, 2 parts of hydroxyethyl methacrylate, 1 part of pentaerythritol triacrylate, and 0.2 parts of 2,2-dimethoxy-2-phenylacetophenone to 40 parts of N,N-dimethylformamide, irradiating with ultraviolet light for 40 minutes under nitrogen protection, centrifuging, washing, and drying to obtain grafted silica;

[0047] (c) 100 parts of polypropylene matrix resin (spinning grade PP with a melt index of 20-35 g / 10 min is selected in this embodiment), 4 parts of grafted silica, 3 parts of acrylic acid grafted polypropylene compatibilizer (PP-g-AA compatibilizer of Lushan Chemical is used in this embodiment, with a grafting rate of 0.56%), 0.3 parts of polycarboxylate ether, 0.4 parts of antioxidant (Irganox The masterbatch is added into a twin-screw extruder to prepare a masterbatch (the temperature during the preparation process is controlled at 170-190° C.), and then the masterbatch is melt-spun through a single-screw spinning machine, the temperatures of zones 1-4 of the single-screw spinning machine are 175° C., 185° C., 190° C., and 180° C., and the spinning speed is 700 m / min. The fiber produced by the melt spinning process is immersed in an impregnation solution containing 0.1% by mass of polycarboxylate ether and 0.05% of a silane coupling agent at a temperature of 50-55° C. for 30 seconds; the immersed fiber is subjected to a primary stretching at a temperature of 10-30° C. with a stretching ratio controlled within the range of 1.6-2.0; then, the fiber is subjected to a secondary stretching at a temperature of 105-115° C. with a stretching ratio controlled within the range of 2.0-2.4, and a total stretching ratio controlled within the range of 3.6-4.2; the stretched fiber is relaxed in saturated steam at 100-110° C. for 4-6 minutes, and wound and collected to produce a modified polypropylene fiber.

[0048] Preparation of corrosion-resistant concrete curbstones

[0049] 1150 parts by mass of high-strength crushed stone (granite crushed stone is used in this embodiment) with a particle size of 5-15 mm and 660 parts of machine-made sand with a fineness modulus of 2.6-3.0 are put into a mixer and dry-mixed for 15-30 seconds; then 330 parts of ordinary Portland cement, 65 parts of fly ash, 86 parts of slag powder, 23 parts of silica fume, 12 parts of metakaolin, 1.5 parts of modified polypropylene fiber (the length of the modified polypropylene fiber is controlled within the range of 10-20 mm), and a water reducer (RHEOPLUS is used in this embodiment) are added. 410) 6 parts, air entraining agent (FA2280 is used in this embodiment) 0.08 parts, dry-mix for 90-120s; then, add 140 parts of water and wet-mix for 90-120s to obtain a mixture; pour the mixture evenly into a mold coated with a release agent, place the mold on a high-frequency vibration table and vibrate at a frequency of 50-100 Hz and an amplitude of 0.5-1.0 mm until the surface of the mixture is slurried and bubbles basically stop overflowing, then continue to vibrate for 10 seconds, then stop vibrating and smooth the surface, then let it stand for 2-4 hours in an environment with a temperature of 15-25°C and a relative humidity of ≥90%, then demold and perform standard curing to obtain an anti-corrosion concrete curbstone.

[0050] Comparative Example

[0051] Select concrete curbstones for road engineering currently sold on the market.

[0052] Performance Testing

[0053] The performance test results of Examples 1-4 and the comparative example are shown in Table 1:

[0054] Table 1

[0055]

[0056] The anti-corrosion concrete curbstones prepared in Examples 1-4 are far superior to the currently commercially available concrete curbstones in terms of compressive strength, salt erosion resistance, sulfate erosion resistance, frost resistance, chloride ion diffusion coefficient, etc.

[0057] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present invention, which are used to illustrate the technical solutions of the present invention rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the above-mentioned embodiments, ordinary technicians in this field should understand that any technician familiar with this technical field can still modify the technical solutions recorded in the above-mentioned embodiments within the technical scope disclosed by the present invention, or make equivalent replacements for some of the technical features therein. These modifications, changes or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered by the protection scope of the present invention.

Claims

1. An anti-corrosion concrete curbstone, characterized in that: The invention comprises the following components in parts by mass: 1000-1200 parts of coarse aggregate, 650-700 parts of fine aggregate, 320-350 parts of cement, 60-80 parts of fly ash, 80-100 parts of slag powder, 20-30 parts of silica fume, 10-20 parts of metakaolin, 1-2 parts of modified polypropylene fiber, 5-10 parts of water reducer, 0.05-0.15 parts of air entraining agent and 130-150 parts of water.

2. The anti-corrosion concrete curbstone according to claim 1, characterized in that: The coarse aggregate is high-strength crushed stone with a particle size of 5-15 mm, and the fine aggregate is machine-made sand with a fineness modulus of 2.6-3.

0.

3. The anti-corrosion concrete curbstone according to claim 1, characterized in that: The water reducer is a polycarboxylic acid-based high-performance water reducer, and the air entraining agent is a special air entraining agent for polycarboxylic acid-based high-performance water reducer.

4. The anti-corrosion concrete curbstone according to claim 1, characterized in that: The length of the modified polypropylene fiber is controlled within the range of 10-20 mm.

5. The anti-corrosion concrete curbstone according to claim 1, characterized in that: The preparation method of the modified polypropylene fiber is: (a) adding nano-silica to an ethanol aqueous solution having a volume fraction of 80-90%, stirring and dispersing the mixture, adding a silane coupling agent, reacting the mixture at a temperature of 70-80° C. for 6 h, and centrifuging and washing the mixture to obtain modified silica; (b) adding modified silica, hydroxyethyl methacrylate, pentaerythritol triacrylate, and 2,2-dimethoxy-2-phenylacetophenone to N,N-dimethylformamide, irradiating the mixture with ultraviolet light for 40 minutes under nitrogen protection, washing the mixture by centrifugation, and drying the mixture to obtain grafted silica; (c) A polypropylene matrix resin, grafted silica, an acrylic acid grafted polypropylene compatibilizer, a polycarboxylate ether, and an antioxidant are added to a twin-screw extruder to prepare a masterbatch, which is then melt-spun, post-treated, and wound and collected through a single-screw spinning machine to obtain modified polypropylene fibers.

6. The anti-corrosion concrete curbstone according to claim 5, characterized in that: The post-processing in the step (c) comprises the following steps: (1) soaking the fibers produced by the melt spinning process in an impregnation solution containing 0.1% by mass of polycarboxylate ether and 0.05% by mass of a silane coupling agent at a temperature of 50-55° C. for 30 seconds; (2) The soaked fiber is subjected to primary stretching at a temperature of 10-30°C, with the stretching ratio controlled within the range of 1.6-2.0; then, the fiber is subjected to secondary stretching at a temperature of 105-115°C, with the stretching ratio controlled within the range of 2.0-2.4, and the total stretching ratio is controlled within the range of 3.6-4.2; (3) The stretched fiber is relaxed in saturated steam at 100-110°C for 4-6 minutes.

7. The anti-corrosion concrete curbstone according to claim 5, characterized in that: The mass ratio of nano-silica to silane coupling agent in the step (a) is 5:

2.

8. The anti-corrosion concrete curbstone according to claim 5, characterized in that: In the step (c), the mass ratio of the polypropylene matrix resin, the grafted silica, the acrylic acid grafted polypropylene compatibilizer, the polycarboxylate ether, and the antioxidant is 100:4:3:0.4:0.

3.

9. A method for preparing the anti-corrosion concrete curbstone according to any one of claims 1 to 8, characterized in that: The coarse aggregate and fine aggregate are put into a mixer and dry-mixed for 15-30 seconds; cement, fly ash, slag powder, silica fume, metakaolin, modified polypropylene fiber, water reducer, and air entraining agent are then added and dry-mixed for 90-120 seconds; water is then added and wet-mixed for 90-120 seconds to obtain a mixture; the mixture is evenly poured into a mold coated with a release agent, and the mixture is vibrated to form, demolded, and subjected to standard curing to obtain an anti-corrosion concrete curbstone.

10. The method for preparing the anti-corrosion concrete curbstone according to claim 9, characterized in that: The vibrating molding process is: using a vibrating device at a frequency of 50-100 Hz and an amplitude of 0.5-1.0 mm to vibrate until the surface of the mixture is slurried and bubbles basically stop overflowing, then continuing to vibrate for 10 seconds, and then stopping the vibration to smooth the surface.

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