Fiber-reinforced carbonized concrete and preparation method thereof

Abstract

The invention discloses fiber reinforced carbonized concrete, which is characterized by being prepared from the following components in parts by mass: 400 to 600 parts of carbonizable cementing material, 800 to 1000 parts of fine aggregate, 800 to 1000 parts of coarse aggregate, 1 to 10 parts of reinforced composite fiber, 1 to 5 parts of additive and 80 to 150 parts of water, the reinforced composite fiber comprises a heat-resistant high-strength fiber and a low-density polyethylene layer coated on the surface of the heat-resistant high-strength fiber. According to the invention, by utilizing the characteristic that the outer layer material melts to form pores when the reinforced composite fiber is heated and carbonized, the diffusion efficiency of CO2 in the concrete product is improved, the carbonization depth is obviously increased, and the contradiction between the CO2 mineralization depth and the pores of the concrete matrix is effectively solved; a concrete pore structure and a fiber interface transition area can be optimized, and a pore-reinforcement synergistic reinforcement effect is achieved; in addition, the carbonization curing period of the concrete product can be remarkably shortened by combining the heating curing with the melting pore diffusion effect, and the applicability is wide.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of building materials, and particularly relates to a fiber-reinforced carbonized concrete and a preparation method thereof. BACKGROUND

[0002] Carbon dioxide curing technology is an environmentally friendly technology that uses carbon dioxide to react with silicate minerals in building materials to achieve carbon sequestration and improve material performance. During the carbon dioxide curing process, CO2 reacts with dicalcium silicate, tricalcium silicate, and hydration products in cement clinker to form calcium carbonate. The carbonation product can quickly fill the pores of the concrete, forming a dense structure that allows for rapid development of early strength and greatly shortens the curing period. At the same time, the concrete product is transformed into a "carbon sink", effectively sequestering CO2 emitted by industry inside the concrete.

[0003] Currently, there are still many technical difficulties and bottlenecks in the field of carbon dioxide curing concrete products. Among them, the contradiction between the depth of carbon dioxide mineralization and the pores of the concrete matrix is particularly prominent. If the porosity is increased to promote the diffusion and mineralization of carbon dioxide, it will easily lead to low matrix strength and poor durability. If the porosity is reduced to increase the matrix density, it will be difficult for carbon dioxide to diffuse deeply, limiting the depth of carbonation curing.

[0004] Patent CN115650663A discloses a preparation method for ultra-high performance concrete using carbon dioxide as an internal curing agent. PEI-coated steel fibers are used to capture CO2, which is then incorporated into the concrete after static curing to obtain ultra-high performance concrete. This scheme uses CO2 internal curing technology to increase the diffusion range and achieve mineralization inside the concrete with high density. However, the amount of CO2 captured by PEI-coated steel fibers is limited, and the carbon reduction and carbon reduction effect is not sufficient. Moreover, it cannot achieve deep mineralization, and the alkalinity of the cured concrete is reduced, which poses a risk of corrosion of steel fibers.

[0005] In order to solve the problem of limited CO2 diffusion range in carbonation curing concrete and to achieve deep mineralization, it is necessary to develop a technology that significantly increases the diffusion range of CO2 and improves the mineralization depth of concrete. SUMMARY

[0006] The main purpose of the present application is to solve the problems and deficiencies of existing carbon dioxide curing technology. A fiber-reinforced carbonized concrete and a preparation method thereof are provided. In the high-density concrete, carbon dioxide enters the interior of the concrete through the pores formed by the melting of the outer layer of the reinforcing composite fiber, achieving deep diffusion and mineralization. This significantly reduces the carbon footprint of the concrete product while improving the strength of the concrete.

[0007] To achieve the above object, the technical scheme adopted by the present application is as follows: a fiber-reinforced carbonized concrete, comprising the following components in mass fraction: carbonizable cementitious material 400-600 parts, fine aggregate 800-1000 parts, coarse aggregate 800-1000 parts, reinforcing composite fiber 1-10 parts, additive 1-5 parts, and water 80-150 parts; the reinforcing composite fiber comprises heat-resistant high-strength fiber and a low-density polyethylene layer coated on the surface of the heat-resistant high-strength fiber.

[0008] Further, the water-binder ratio of the fiber-reinforced carbonized concrete is 0.2-0.3.

[0009] According to the above scheme, the heat-resistant high-strength fiber can be selected from one or more of carbon fiber, glass fiber, and aramid fiber.

[0010] According to the above scheme, the melting point of the low-density polyethylene material is 105-115℃.

[0011] Further, the volume ratio of the introduced heat-resistant high-strength fiber and low-density polyethylene material is 0.13-0.56:1.

[0012] According to the above scheme, the average length of the reinforcing composite fiber is 12-24mm, and the average diameter is 40-60μm.

[0013] According to the above scheme, the reinforcing composite fiber is obtained by melt co-extrusion using heat-resistant high-strength fiber and low-density polyethylene material as the main raw materials.

[0014] Further, in the reinforcing composite fiber, the outer layer structure adopts low-density polyethylene fiber with a low melting point (105-115℃), and when carbonized at high temperature, the outer layer structure melts to form pores; in combination with the dispersion effect of the reinforcing composite fiber in the concrete system, a rich pore network is formed, which is beneficial to the deep diffusion of CO2; the inner layer structure adopts heat-resistant high-strength fiber with a high melting point and high strength, which can still retain structural integrity after the outer layer material melts to simultaneously enhance the mechanical properties of the concrete. Through the pore formation by melting of the outer layer, the CO2 diffusion efficiency is effectively improved, and the residual fiber in the inner layer provides sustained strength, realizing the synergistic strengthening function of "pore-reinforcement".

[0015] Further, the preparation steps of the reinforced composite fiber include: (1) material pretreatment: drying the low-density polyethylene particles used in the outer layer and adding 3-5wt% of maleic anhydride grafted polyethylene as a compatibilizer; heating the heat-resistant high-strength fiber used in the inner layer to 80-110℃; (2) melt extrusion: heating and melting the dried outer layer low-density polyethylene base material (containing low-density polyethylene particles and a compatibilizer) to obtain an outer layer melt; (3) coating and compounding: guiding the heat-resistant high-strength fiber through the coating die, while pumping the outer layer melt into the die, so that the outer layer melt uniformly coats the outer surface of the inner layer heat-resistant high-strength fiber bundle to form a composite fiber bundle; (4) cooling and setting: solidifying the obtained composite fiber bundle in a 20-30℃ cooling water tank, while adjusting the draw speed by 1-3 times, so that the average diameter of the inner layer fiber structure is 15-30μm and the average thickness of the outer layer structure is 10-15μm; (5) secondary processing: cutting the obtained composite fiber bundle and performing plasma treatment to obtain the reinforced composite fiber.

[0016] Further, the low-density polyethylene material is heated using a single-screw extruder, the heating temperature is 120-180℃, and the screw rotation speed is 20-60rpm.

[0017] According to the above scheme, the plasma treatment conditions include: using oxygen as the working gas, the working pressure is 1.0-1.5mbar, the radio frequency power is 200-300W, and the treatment time is 2-4min.

[0018] According to the above scheme, the carbonizable cementitious material includes two or more of low-carbon cement, ordinary portland cement, portland cement, sulphoaluminate cement, slag powder, fly ash, lithium slag powder, and phosphorous slag powder, wherein the cement accounts for 40-70% of the mass of the cementitious material.

[0019] Further, the specific surface area of the carbonizable cementitious material is 300-450m 2 / kg.

[0020] Further, in the low-carbon cement, the main mineral components and their mass percentages include: C3S 30-50%, CS 10-30%, and C2S 40-60%.

[0021] According to the above scheme, the fine aggregate has a particle size of 0-5mm, a powder content of 3-5%, and a fineness modulus of 2.6-3.0.

[0022] According to the above scheme, the coarse aggregate has a particle size of 5-25mm and forms a continuous gradation with the fine aggregate; by optimizing the aggregate gradation, the packing density of the aggregate is improved, the inherent pores in the concrete are reduced, and the pores generated by the melting of the fiber become the main channel for the diffusion of CO2.

[0023] According to the above scheme, the additive is a high-performance polycarboxylic acid water reducing agent, and the water reducing rate is greater than or equal to 25%.

[0024] The application further provides a preparation method of the fiber-reinforced carbonized concrete. (1) uniformly stir fine aggregate, coarse aggregate and reinforcing composite fibers according to the proportions; (2) add carbonizable cementitious materials, additives and water according to the proportions, and uniformly stir to obtain a concrete mixture; (3) place the concrete mixture obtained in step (2) in a mold, and perform mold curing at room temperature to obtain a concrete blank; (4) place the obtained concrete blank in a carbon dioxide environment for heating and curing to obtain the fiber-reinforced carbonized concrete.

[0025] According to the above scheme, the heating and curing is performed at a temperature of 110-150 DEG C, and the carbon dioxide concentration is 10-100 vol%.

[0026] According to the above scheme, the heating and curing is performed at a temperature of 110-150 DEG C, and the carbon dioxide concentration is 10-100 vol%.

[0027] Further, the heating and curing is performed at a pressure of 0.1-0.5 MPa.

[0028] Further, the heating and curing is performed at a pressure of 0.1-0.5 MPa.

[0029] Preferably, the heating and curing is performed at a pressure of 0.1-0.5 MPa.

[0030] According to the above scheme, the heating and curing is performed at a pressure of 0.1-0.5 MPa.

[0031] Compared with the prior art, the application has the following beneficial effects: (1) The application utilizes the characteristics of the outer layer material of the reinforcing composite fiber melting and forming pores during heating and carbonization, effectively improves the diffusion efficiency of CO2 in the concrete product, effectively increases the carbonization depth, and significantly improves the CO2 storage rate of the concrete product; the nanoscale CaCO3 carbonization product generated by the reaction of CO2 and cement is filled in the pores of the concrete, optimizes the pore structure of the concrete, and promotes the compactness and strength of the concrete.

[0032] (2) The outer layer of the reinforced composite fiber melts, and the heat-resistant high-strength fiber in the inner layer still retains an intact structure. The rough outer layer pore interface after melting is conducive to improving the bonding force between the inner layer fiber and the carbonation product and the hydration product, is conducive to optimizing the fiber interface transition zone, and thus significantly improves the strength of the concrete, and realizes the synergistic strengthening function of "pore-reinforcement".

[0033] (3) The carbonation curing time of the concrete product is greatly shortened. On the one hand, the hydration / carbonation rate is improved by heating curing conditions, and on the other hand, the diffusion efficiency of CO2 is significantly improved by using the reinforced composite fiber pores formed by heating and melting, thereby shortening the carbonation period. The heating curing and the diffusion effect of the melting pores formed by heating and melting are synergistic, and the carbonation curing period of the concrete product is significantly shortened.

[0034] (4) In the carbonation curing, the present application mainly relies on the melting pores on the surface of the reinforced composite fiber formed by heating curing to promote the diffusion of CO2, which can effectively eliminate the limitation of the traditional CO2 diffusion channel which is usually affected by the compactness of the concrete, and can be further applied to the preparation of concrete with high compactness such as low water-binder ratio, thereby effectively solving the contradiction between the CO2 mineralization depth and the pores of the concrete matrix. DETAILED DESCRIPTION

[0035] In order to more clearly understand the purposes, technical solutions and beneficial effects of the present application, the present application will be described in detail in conjunction with specific embodiments.

[0036] In the following examples, the obtained concrete is tested for performance by the following method: The mechanical properties of the concrete after carbonation curing are tested according to the "Standard Test Method for Physical and Mechanical Properties of Concrete" (GB / T 50081-2019); the porosity of the concrete after carbonation is tested by the Archimedes water saturation method; and the carbonation depth of the concrete after carbonation curing is tested according to the "Standard Test Method for Long-Term Performance and Durability of Concrete" (GB / T 50082-2024).

[0037] In the following examples, the content of C3S2 in the low-carbon cement is 32wt%, the content of CS is 27wt%, the content of C2S is 41wt%, and the calcium-silicon ratio is 1.7; the ordinary portland cement is PO42.5 grade; the sulphoaluminate cement is fast-hardening type 42.5 grade; the slag powder is S95 grade; the fly ash is II grade fly ash; the SiO2 content in the lithium slag powder is 53wt%, and the Al2O3 content is 17wt%.

[0038] The low-density polyethylene used is provided by China Petroleum Chemical Co., Ltd., and has a density of 0.92g / cm 3 and a melting point of 105-110℃.

[0039] Example 1 A fiber reinforced carbonized concrete, each component and the weight percentage are as follows: carbonizable binder 400 parts, fine aggregate 1000 parts, coarse aggregate 900 parts, reinforcing composite fiber 2 parts, additive 1 part, mixing water 120 parts, concrete water binder ratio 0.30.

[0040] The carbonizable binder used is a mixture of low carbon cement and slag powder, wherein the low carbon cement accounts for 70% of the total mass of the binder, the specific surface area is 350 m 2 / kg; The fine aggregate used is machine-made sand, the particle size is 0~5mm, the powder content is 5%, and the fineness modulus is 2.9; The coarse aggregate used is limestone gravel, the particle size is 5~25mm, and it forms a continuous gradation with the fine aggregate; The average length of the reinforcing composite fiber used is 18mm, and the average diameter is 40μm; The additive used is a powdery high-performance polycarboxylic acid water reducer, and the water-reducing rate is 25%; The reinforcing composite fiber has a double-layer composite structure, the inner layer structure material uses glass fiber, and the outer layer structure material uses low-density polyethylene; the volume ratio of the introduced glass fiber and low-density polyethylene material is 0.33:1.

[0041] The specific preparation steps of the reinforcing composite fiber include: (1) material pretreatment: drying the low-density polyethylene particles used for the outer layer structure of the reinforcing composite fiber, and adding 5wt% of maleic anhydride grafted polyethylene (compatibilizer) mixed uniformly; the glass fiber used for the inner layer structure of the reinforcing composite fiber passes through a tension sensor, a godet and a preheating device in turn, and the glass fiber is heated to 80~110℃ through the preheating device; (2) melt extrusion: the outer layer mixture obtained in step (1) is heated and melted by a single screw extruder (temperature range is 120~180℃, screw rotation speed is 60rpm), to obtain an outer layer melt; (3) coating and compounding: the inner layer glass fiber is guided to pass through a coating die to form a glass fiber bundle, and the outer layer melt is pumped into the die, so that the outer layer melt uniformly coats the surface of the glass fiber bundle to form a composite fiber bundle; (4) cooling and setting: the obtained composite fiber bundle is solidified in a 20~30℃ cooling water tank, and the drawing speed is adjusted to 3 times, so that the average diameter of the inner layer fiber structure is 20μm, and the average thickness of the outer layer structure is 10μm; (5) secondary treatment: the obtained composite fiber bundle is cut and subjected to plasma treatment (using oxygen as the working gas, working pressure is 1.0mbar, radio frequency power is 250W, and treatment time is 2min), to obtain the reinforcing composite fiber with an average length of 18mm and an average diameter of 40μm.

[0042] The preparation method of the fiber reinforced carbonized concrete includes the following steps: (1) Put the fine aggregate, coarse aggregate and reinforcing composite fiber with the proportioning weight into the stirring pot and stir for 120 s; (2) Put the carbonizable cementing material, additive and mixing water with the proportioning weight into the stirring pot and stir for 180 s, to obtain the concrete mixture; (3) Put the concrete mixture obtained in step (2) into a mold for molding, and after curing in the mold at 20℃ for 24 h, a concrete blank is obtained; (4) Put the concrete blank obtained in step (3) into a carbon dioxide reaction kettle for curing, increase the temperature to 110℃ at a rate of 5℃ / min, then introduce 20% CO2, maintain the pressure in the reaction kettle at 0.1 MPa, and cure at constant temperature for 16 h, to obtain the fiber-reinforced carbonized concrete.

[0043] Example 2 A fiber-reinforced carbonized concrete, the components and the weight fractions are as follows: carbonizable cementing material 600 parts, fine aggregate 800 parts, coarse aggregate 900 parts, reinforcing composite fiber 6 parts, additive 5 parts, mixing water 120 parts, and the water-binder ratio of the concrete is 0.20; The carbonizable cementing material used is a mixture of ordinary portland cement and fly ash, wherein the ordinary portland cement accounts for 50% of the total mass of the cementing material, and the specific surface area is 350 m 2 / kg; The fine aggregate used is machine-made sand, with a particle size of 0-5 mm, a powder content of 3%, and a fineness modulus of 2.8; The coarse aggregate used is limestone gravel, with a particle size of 5-25 mm, and forms a continuous gradation with the fine aggregate; The reinforcing composite fiber used has an average length of 24 mm and an average diameter of 50 μm; The additive used is a powdery high-performance polycarboxylic acid water reducer, with a water-reducing rate of 30%; The reinforcing composite fiber has a double-layer composite structure, wherein the inner layer structure material is glass fiber, and the outer layer structure material is low-density polyethylene; The preparation method of the reinforcing composite fiber is substantially the same as that of Example 1, except that: 1) The volume ratio of the introduced glass fiber and low-density polyethylene material is 0.19:1; 2) The temperature range for melt single-screw rod heating processing is 120-180℃, and the screw rod rotation speed is 30 rpm; 3) The drawing speed is adjusted to 1 times, so that the average diameter of the inner layer fiber structure is 20 μm, and the average thickness of the outer layer structure is 15 μm; 4) The plasma treatment conditions are as follows: oxygen is used as the working gas, the working pressure is 1.0 mbar, the radio frequency power is 200 W, and the treatment time is 3 min.

[0044] The preparation method of the fiber-reinforced carbonized concrete comprises the following steps: (1) Put the fine aggregate, coarse aggregate and reinforcing composite fiber according to the proportion into a stirring pot and stir for 120 s; (2) Then put the cementitious material, additive and mixing water according to the proportion into the stirring pot and stir for 180 s to obtain a concrete mixture; (3) Put the concrete mixture obtained in step (2) into a mold for molding, and after curing in a 20℃ environment for 24 h, a concrete blank is obtained; (4) Put the concrete blank obtained in step (3) into a carbon dioxide reaction kettle for curing, increase the temperature to 150℃ at a rate of 3℃ / min, then pass in CO2 with a concentration of 20%, maintain the pressure in the reaction kettle at 0.5 MPa, and cure for 8 h to obtain the fiber-reinforced carbonized concrete.

[0045] Example 3 A fiber-reinforced carbonized concrete, the components and the weight percentage are as follows: carbonizable cementitious material 500 parts, fine aggregate 1000 parts, coarse aggregate 800 parts, reinforcing composite fiber 4 parts, additive 3 parts, mixing water 100 parts, and the water-cement ratio of the concrete is 0.20; The carbonizable cementitious material used is a mixture of low-carbon cement, sulphoaluminate cement and lithium slag powder, wherein the low-carbon cement accounts for 50% of the total mass of the cementitious material, and the sulphoaluminate cement accounts for 10% of the total mass of the cementitious material; the specific surface area is 420 m 2 / kg; The fine aggregate used is natural sand with a particle size of 0-5 mm, a powder content of 5%, and a fineness modulus of 2.9; The coarse aggregate used is dolomite gravel with a particle size of 5-25 mm, which forms a continuous gradation with the fine aggregate; The reinforcing composite fiber used has an average length of 12 mm and an average diameter of 40 μm; The additive used is a liquid high-performance polycarboxylic acid water reducer with a water-reducing rate of 25%; The reinforcing composite fiber has a double-layer composite structure, the inner layer structure material is aramid fiber, and the outer layer structure material is low-density polyethylene.

[0046] The preparation method of the reinforcing composite fiber is substantially the same as that of Example 1, except that: 1) The volume ratio of the introduced aramid fiber and low-density polyethylene material is 0.33:1; 3wt% of maleic anhydride grafted polyethylene is added as a compatibilizer; 2) The temperature range for melt single-screw rod heating processing is 120-180℃, and the screw rod rotation speed is 40 rpm; 3) the drawing speed is adjusted by 2 times, the average diameter of the inner fiber structure is 20 μm, and the average thickness of the outer structure is 10 μm; 4) the plasma treatment condition is that oxygen is used as the working gas, the working pressure is 1.0 mbar, the radio frequency power is 200 W, and the treatment time is 4 min.

[0047] The preparation method of the fiber-reinforced carbonized concrete comprises the following steps: (1) fine aggregate, coarse aggregate and reinforcing composite fiber are weighed according to the proportion, and then are put into a stirring pot and stirred for 120 s; (2) cementitious material, additive and mixing water are weighed according to the proportion, and then are added into the stirring pot and stirred for 180 s, so that a concrete mixture is obtained; (3) the concrete mixture obtained in step (2) is put into a mold for molding, and a concrete blank is obtained after being cured in a 20 ℃ environment with the mold for 12 h; (4) the concrete blank obtained in step (3) is placed in a carbon dioxide reaction kettle for curing, the temperature is increased to 130 ℃ at a rate of 5 ℃ / min, 20% CO2 is introduced, the pressure in the reaction kettle is kept at 0.4 MPa, and the curing is performed for 12 h, so that the fiber-reinforced carbonized concrete is obtained.

[0048] Example 4 A fiber-reinforced carbonized concrete, wherein the difference between the formula and the preparation method of the fiber-reinforced carbonized concrete and those of Example 1 is that, in step (4), the curing time is 24 h, and the remaining curing conditions are kept unchanged.

[0049] Comparative Example 1 A fiber-reinforced carbonized concrete, wherein the difference between the formula and the preparation method of the fiber-reinforced carbonized concrete and those of Example 1 is that the amount of mixing water is 170 parts, and the water-binder ratio of the concrete is 0.43.

[0050] Comparative Example 2 A fiber-reinforced carbonized concrete, wherein the difference between the formula and the preparation method of the fiber-reinforced carbonized concrete and those of Example 2 is that the reinforcing composite fiber is replaced by ordinary glass fiber with the same length and diameter specifications.

[0051] Comparative Example 3 A fiber-reinforced carbonized concrete, wherein the difference between the formula and the preparation method of the fiber-reinforced carbonized concrete and those of Example 3 is that the coarse aggregate particle size is 5-31.5 mm, and the coarse aggregate does not form a continuous gradation with the fine aggregate.

[0052] Comparative Example 4 A fiber-reinforced carbonized concrete, wherein the difference between the formula and the preparation method of the fiber-reinforced carbonized concrete and those of Example 1 is that, in step (4), the obtained concrete blank is placed in a carbon dioxide reaction kettle with the temperature having been raised to 110 ℃ in advance (without the temperature increasing step in the application), and the remaining curing conditions are kept unchanged.

[0053] Comparative Example 5 A fiber-reinforced carbonized concrete, the only difference between its formula and preparation method and that of Example 1 is that in step (4), the obtained concrete blank is placed in a carbon dioxide reactor for curing, and after being heated to 100°C at a rate of 5°C / min, the remaining curing conditions are kept the same.

[0054] The test results of the mechanical properties and carbonation depth of the concrete described in Examples 1-4 and Comparative Examples 1-5 are shown in Table 1.

[0055] Table 1. Performance test results of the concrete described in Examples 1-4 and Comparative Examples 1-5

[0056] The performance test results above show that the compressive strength, flexural strength, porosity and carbonation depth of the fiber-reinforced carbonized concrete in Examples 1-4 are significantly better than those in Comparative Examples 1-5. Among them, after extending the carbonation curing time, the performance of Example 4 is basically the same as that of Example 1, indicating that the present invention can effectively shorten the curing cycle.

[0057] The embodiments of the present invention have been described above. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A fiber reinforced carbonated concrete, characterized by, The composition comprises the following quality parts: carbonizable cementing material 400-600 parts, fine aggregate 800-1000 parts, coarse aggregate 800-1000 parts, reinforced composite fiber 1-10 parts, additive 1-5 parts, and water 80-150 parts; the reinforced composite fiber comprises heat-resistant high-strength fiber and a low-density polyethylene layer coated on the surface of the heat-resistant high-strength fiber.

2. The fiber reinforced carbonated concrete according to claim 1, characterized in that, The water-binder ratio of the fiber-reinforced carbonized concrete is 0.2-0.

3.

3. The fiber reinforced carbonated concrete according to claim 1, wherein, The heat-resistant high-strength fiber can be selected from one or more of carbon fiber, glass fiber, and aramid fiber.

4. The fiber reinforced carbonated concrete according to claim 1, wherein, The melting point of the low-density polyethylene material is 105-115 DEG C.

5. The fiber reinforced carbonated concrete according to claim 1, wherein, The average length of the reinforced composite fiber is 12-24 mm, and the average diameter is 40-60 microns.

6. The fiber reinforced carbonated concrete according to claim 1, wherein, The carbonizable cementing material comprises two or more of low-carbon cement, ordinary portland cement, Portland cement, sulphoaluminate cement, slag powder, fly ash, lithium slag powder, and phosphorous slag powder, wherein the cement raw material accounts for 40-70% of the mass of the cementing material.

7. The fiber reinforced carbonated concrete according to claim 1, wherein, The fine aggregate has a particle size of 0-5 mm, a powder content of 3-5%, and a fineness modulus of 2.6-3.0; the coarse aggregate has a particle size of 5-25 mm and forms a continuous gradation with the fine aggregate.

8. The fiber reinforced carbonated concrete of claim 1, wherein, The additive is high-performance polycarboxylic acid water reducing agent, and the water-reducing rate is greater than or equal to 25%.

9. A method of producing the fiber reinforced carbonated concrete according to any one of claims 1 to 8, characterized by, The method comprises the following steps: (1) uniformly stirring the fine aggregate, coarse aggregate, and reinforced composite fiber according to the proportions; (2) adding the carbonizable cementing material, additive, and water according to the proportions, and uniformly stirring to obtain a concrete mixture; (3) placing the concrete mixture obtained in step (2) in a mold, curing at room temperature, and obtaining a concrete blank; (4) placing the concrete blank in a carbon dioxide environment for heating and curing, and obtaining the fiber-reinforced carbonized concrete.

10. The method of claim 9, wherein, The heating and curing is performed at a temperature of 110-150 DEG C and a carbon dioxide concentration of 10-100 vol%.

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