Low-carbon plant-growing concrete, low-carbon plant-growing concrete component and preparation method thereof

Abstract

This invention provides a low-carbon vegetated concrete, low-carbon vegetated concrete components, and their preparation method. Modified coal gangue ceramsite is used as coarse aggregate, and ordinary coal gangue ceramsite as fine aggregate. Two low-carbon cementitious systems are provided: cement-coal gangue micropowder and phosphogypsum-based. Both systems significantly reduce cement usage and carbon emissions. Combined with water-reducing agents, water-retaining agents, and slow-release nutrients, the components are prefabricated and cured according to standard procedures to produce low-carbon vegetated concrete components. The 28-day compressive strength of the low-carbon vegetated concrete components is 2.5–3 MPa, with a porosity of 30%–35%, exhibiting excellent erosion resistance. The high porosity of these components promotes root growth, with an initial survival rate ≥85%, enabling long-term ecological succession. This solution solves the problems of high carbon content, pore blockage, low solid waste utilization, and unstable on-site construction quality associated with traditional vegetated concrete. It is suitable for ecological restoration projects such as slopes, mines, and rivers, combining low-carbon environmental protection, engineering stability, and industrialization value.

Description

Technical Field

[0001] This invention belongs to the field of ecological building materials technology, specifically relating to a low-carbon vegetated concrete, low-carbon vegetated concrete components and their preparation methods. Background Technology

[0002] Vegetated concrete, also known as vegetation concrete, greening concrete, ecological reverse filter vegetated concrete, etc., is widely used in slope protection, mine ecological restoration, highway slope protection materials and other scenarios. It can achieve ecological planting while realizing safety protection, and is a new type of slope protection material that can combine engineering protection and ecological restoration well.

[0003] However, with the deepening of the low-carbon and environmental protection concept, the continuous improvement of ecological restoration requirements, and the development needs of standardization and industrialization in engineering construction, there are still many prominent drawbacks in the production, preparation, functional performance, and engineering application of planted concrete, which restrict its large-scale promotion and high-quality application. The specific manifestations are as follows: Firstly, the cementitious materials used in current vegetation concrete are mostly pure silicate cement, which requires a large amount of limestone, coal and other resources to produce, and has a high carbon emission intensity, which is contrary to the concept of low carbon and environmental protection.

[0004] Secondly, most existing vegetated concrete products excessively pursue the mechanical strength required for engineering protection, blindly increasing the cement content, resulting in an overly dense and hard concrete matrix with a large number of internal pores being blocked. This makes it difficult for vegetation roots to penetrate the matrix to absorb water and nutrients, resulting in an extremely low vegetation survival rate and difficulty in forming a stable vegetation cover.

[0005] Third, the utilization of industrial solid waste (coal gangue, fly ash, and slag, etc.) in planted concrete is relatively simple, mostly used as simple substitutes for aggregates, failing to give full play to the chemical activity and physical properties of solid waste, and failing to achieve the full-component, tiered, and high-value utilization of solid waste, thus wasting resources.

[0006] Fourth, the commonly used aggregates in current vegetation concrete have a single morphology. Although smooth cylindrical expanded clay aggregates have high porosity, they have poor interlocking between particles; while irregular crushed stone has weak water and fertilizer retention capacity, which is not conducive to vegetation growth. Neither of them can achieve structural stability and meet the needs of vegetation growth.

[0007] Fifth, most existing vegetation concrete products adopt the on-site wet mixing and pouring construction method. The construction process is greatly affected by factors such as ambient temperature, humidity and operator skill, which can easily lead to problems such as uneven mixing, insufficient pouring density and poor surface flatness, resulting in poor construction stability and quality control. At the same time, on-site wet mixing and pouring cannot achieve standardized production, standardized inspection and large-scale supply of products.

[0008] In summary, there is a current need for a new type of vegetated concrete that is low-carbon and environmentally friendly, balances mechanical and ecological performance, can make high-value use of industrial solid waste, uses aggregates that have both structural stability and growth-promoting capabilities, and supports standardized prefabrication construction. This would overcome the drawbacks of existing products, such as high carbon emissions, limited root growth, extensive use of solid waste, single aggregate function, and unstable construction quality. Summary of the Invention

[0009] To achieve the above objectives, the present invention provides the following technical solution: A low-carbon vegetated concrete comprises: aggregates, cementitious materials, admixtures, and mixing water. The aggregates include coarse aggregates and fine aggregates. In each cubic meter of the low-carbon vegetated concrete, the amount of coarse aggregate is 720-750 kg, and the coarse aggregate is modified coal gangue ceramsite with a particle size of 5-25 mm. The amount of fine aggregate is 160-190 kg, and the fine aggregate is ordinary coal gangue ceramsite with a particle size of 5-10 mm or the modified coal gangue ceramsite. The cementitious material adopts any one of the following schemes: Scheme 1: In each cubic meter of the low-carbon vegetated concrete, the total amount of cementitious material is 95-105 kg, and the cementitious material includes 42-48 kg of ordinary Portland cement and 52-58 kg of... Scheme 2: In each cubic meter of the low-carbon vegetated concrete, the total amount of the cementitious material is 90-100 kg, and the cementitious material includes: 65-72 kg of modified phosphogypsum, 22-28 kg of slag powder, and 3-5 kg ​​of the ordinary Portland cement; the admixtures include polycarboxylate superplasticizer and polyacrylamide water-retaining agent, and in each cubic meter of the low-carbon vegetated concrete, the amount of polycarboxylate superplasticizer is 0.18-0.22 kg, and the amount of polyacrylamide water-retaining agent is 0.12-0.18 kg; the amount of mixing water in each cubic meter of the low-carbon vegetated concrete is 40-45 kg.

[0010] In some embodiments, the admixture further includes slow-release nitrogen, phosphorus, and potassium fertilizer and a pH adjuster, wherein the amount of slow-release nitrogen, phosphorus, and potassium fertilizer is 0.007% to 0.01% of the total mass of the cementitious material; and the amount of pH adjuster is 0.003% to 0.005% of the total mass of the cementitious material.

[0011] In some embodiments, the pH adjuster is humic acid.

[0012] This invention also provides a method for preparing low-carbon vegetation concrete components, comprising the following steps: weighing the aggregate, cementitious material, admixture, and mixing water according to the above-mentioned low-carbon vegetation concrete formula; sieving the coarse aggregate and the fine aggregate separately and drying them until the surface moisture content is ≤3%; simultaneously, according to the selected scheme, dry mixing each component corresponding to Scheme 1 or Scheme 2 for 3 minutes to obtain uniform cementitious powder; adding the coarse aggregate and the fine aggregate into a mixer and dry mixing for 1 minute, then adding the cementitious powder and continuing to dry mix for 2 minutes, so that the cementitious powder is uniformly attached to the surface of the aggregate; simultaneously adding the polycarboxylate-based high-efficiency water-reducing agent, the polyacrylamide water-retaining agent, and the mixing water, and wet mixing for 3-4 minutes to obtain a low-carbon vegetation concrete mixture; pouring the low-carbon vegetation concrete mixture into a mold, and then curing it until hardened, finally obtaining the low-carbon vegetation concrete component.

[0013] In some embodiments, the admixture further includes a slow-release nitrogen, phosphorus, and potassium fertilizer and a pH adjuster, wherein the amount of the slow-release nitrogen, phosphorus, and potassium fertilizer is 0.007% to 0.01% of the total mass of the cementitious material; the amount of the pH adjuster is 0.003% to 0.005% of the total mass of the cementitious material; and the slow-release nitrogen, phosphorus, and potassium fertilizer and the pH adjuster are added simultaneously with the cementitious powder.

[0014] In some embodiments, after the low-carbon vegetation concrete mixture is poured into the mold, it is gently vibrated on a vibrating table for 1 to 2 minutes to form the shape and the surface is smoothed. The vibration frequency is 50 Hz.

[0015] In some embodiments, the curing conditions are: curing temperature of 20±2℃ and curing humidity of ≥90%.

[0016] In some embodiments, the coarse aggregate is modified coal gangue ceramsite with a particle size of 5-25 mm. The coarse aggregate is made from cylindrical modified coal gangue sintered ceramsite with a diameter of 10 mm and a length of 15-25 mm. A double-roll crusher is used to perform single-pass light crushing on the cylindrical modified coal gangue sintered ceramsite, with a roller gap of 11 mm and a machine speed of 350 r / min.

[0017] The present invention also provides a low-carbon vegetated concrete component, which is prepared by the above-described method for preparing low-carbon vegetated concrete components.

[0018] Compared with the prior art, the low-carbon vegetated concrete, low-carbon vegetated concrete components and their preparation method provided by the present invention have the following beneficial effects: 1. This invention pioneers two differentiated low-carbon cementitious solutions: Solution 1, a cement-coal gangue powder system, replaces 52%~58% of silicate cement with coal gangue powder, resulting in carbon emission reduction of over 40%; Solution 2, a phosphogypsum-based system, is based on modified phosphogypsum and S95 grade slag powder, with a silicate cement replacement rate of ≥95%, resulting in carbon emission reduction of over 55%. Both solutions can significantly reduce cement usage and carbon emissions, and the two solutions can be adapted to different raw material supply and low-carbon requirements scenarios. 2. In this invention, coal gangue is used to prepare coarse aggregate, fine aggregate and coal gangue powder, and phosphogypsum and slag are used as cementing components to realize the high-value utilization of various industrial solid wastes. The utilization rate of solid waste per cubic meter exceeds 80%, which greatly reduces solid waste accumulation pollution. 3. This invention uses modified coal gangue sintered ceramsite of original specifications from roller crushing to produce angular coarse aggregate, which retains the internal porous water-retaining structure and improves the particle interlocking force; it is combined with 5-10 mm coal gangue ceramsite as fine aggregate to form through pores, which not only ensures the structural stability of concrete components, but also provides an excellent environment for vegetation growth. 4. The highly interconnected pore structure and low-carbon cementitious material provided by this invention, combined with additives and a compounded slow-release nitrogen, phosphorus, and potassium fertilizer and humic acid pH adjuster, can slowly release nutrients, ensuring an overall survival rate of ≥85% in the early stages of vegetation. In the later stages, natural vegetation succession can be achieved, resulting in long-term and stable ecological restoration. 5. The low-carbon vegetated concrete provided by this invention adopts a moderately low-strength design, with the 28-day compressive strength strictly controlled at 2.5-3 MPa. This not only meets the engineering mechanical requirements of slope protection, erosion resistance, and collapse resistance, but also avoids the matrix being too hard and blocking the pores, ensuring that the vegetation roots can easily penetrate. The cemented matrix softens gently in the later stage, realizing natural ecological succession, which is in line with the core design concept of "strength giving way to ecology". 6. The low-carbon concrete component provided by the present invention has excellent erosion resistance. After a simulated rainstorm erosion test for 30 minutes, the component still maintains its integrity and the mass loss is ≤5%. It can be used for a long time in complex environments such as rainy, water-adjacent, and strong wind environments. 7. The low-carbon concrete components provided by this invention are standardized prefabricated and cured, requiring no on-site pouring. They are easy to construct, have controllable quality, and can be industrialized. They are suitable for various ecological projects such as mine restoration, steep slopes, riverbank protection, and gangue mountain management, and are especially suitable for low-load flexible restoration scenarios that require long-term ecological succession. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0020] The present invention will now be described in detail with reference to embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be combined with each other.

[0021] This invention provides a low-carbon vegetated concrete, comprising aggregates, cementitious materials, admixtures, and mixing water. The aggregates include coarse aggregates and fine aggregates. The coarse aggregates are modified coal gangue ceramsite with a particle size of 5–25 mm, and the fine aggregates are ordinary coal gangue ceramsite or modified coal gangue ceramsite with a particle size of 5–10 mm. The amount of coarse aggregate in each cubic meter of low-carbon vegetated concrete is 720–750 kg, and the amount of fine aggregate is 160–190 kg.

[0022] The coarse aggregates mentioned above are prepared using a special double-roll crushing and directional shaping process: cylindrical modified coal gangue sintered ceramsite with a diameter of 10mm and a length of 15-25mm is initially selected, and a double-roll crusher is used with a roller gap of 11mm and a machine speed of 350r / min. Only a single pass of light crushing is performed, and no secondary over-crushed powder is produced throughout the crushing process. The finished modified coal gangue ceramsite has an angular surface structure and a porous internal structure.

[0023] It is important to note that it is strictly forbidden to mix fine powders such as river sand and manufactured sand with a particle size of <5mm into aggregates, so as to avoid clogging of the internal pores of concrete from the source.

[0024] The above-mentioned cementitious material can be any one of the following schemes: Option 1, Cement-Coal Gangue Micropowder System: In each cubic meter of low-carbon vegetation concrete, the total amount of cementitious materials is 95-105 kg, specifically including 42-48 kg of ordinary Portland cement and 52-58 kg of coal gangue micropowder. Among them, the ordinary Portland cement can be compliant commercial Portland cement of strength grade 42.5 and 52.5, etc.; the coal gangue micropowder is a by-product of the fine grinding and deep processing of industrial solid waste coal gangue, and the particle size of the coal gangue micropowder is ≤75μm.

[0025] Compared to a pure silicate cement system, this solution uses coal gangue powder to replace ordinary silicate cement at a stable rate of 52%–58%, resulting in high solid waste resource utilization and significantly reduced carbon emissions. It is suitable for conventional ecological restoration of neutral soil slopes.

[0026] Option 2, Phosphogypsum-based system: The total amount of cementitious materials in each cubic meter of low-carbon vegetated concrete is 90–100 kg, specifically including: 65–72 kg of modified phosphogypsum, 22–28 kg of S95 grade slag powder, and 3–5 kg of ordinary Portland cement. The modified phosphogypsum is preferably Hongguan gypsum, whose main component is phosphogypsum (dihydrate), with a calcium sulfate dihydrate content higher than 80%, 17% water of crystallization, ±3% adsorbed water, and a pH value of 5–6, conforming to standards GB / T 9776-2022 and GB 6566-2010.

[0027] Compared to the pure silicate cement system, the modified phosphogypsum and slag powder in Scheme 2 have a cement replacement rate of ≥95%, and the core cementitious components are all deep-processed industrial solid waste materials, which are low-carbon and environmentally friendly.

[0028] The aforementioned admixtures include polycarboxylate superplasticizers and polyacrylamide water-retaining agents. In each cubic meter of low-carbon vegetated concrete, the dosage of polycarboxylate superplasticizers is 0.18–0.22 kg, and the dosage of polyacrylamide water-retaining agents is 0.12–0.18 kg.

[0029] In some implementations, in practical engineering applications, to meet the long-term greening needs of slopes, the aforementioned admixtures can be compounded with long-term nutrient regulating components as needed, such as slow-release nitrogen, phosphorus, and potassium fertilizers and pH adjusters. The dosage of the slow-release nitrogen, phosphorus, and potassium fertilizer is 0.007% to 0.01% of the total mass of the cementitious material; in this slow-release fertilizer, the percentage content of the three effective nutrients—nitrogen, phosphorus pentoxide, and potassium oxide—is each 15%. The dosage of the pH adjuster is 0.003% to 0.005% of the total mass of the cementitious material. Humic acid is preferably used as the pH adjuster, as it can meet the normal growth physiological needs of native herbaceous plants and shrubs, improving the overall survival rate of the vegetation.

[0030] The amount of mixing water in each cubic meter of low-carbon vegetation concrete is 40-45 kg.

[0031] Based on the above-mentioned low-carbon vegetated concrete formula, this invention also provides a standardized, easy-to-implement, and mass-producible method for preparing low-carbon vegetated concrete components, the steps of which are as follows: S1. Pretreatment of aggregates and cementitious materials: First, according to the mixing ratio requirements, accurately weigh all raw materials required for low-carbon vegetation concrete, including modified coal gangue aggregate, corresponding raw materials for cementitious materials, and functional admixtures. Then, sieve the 5-25mm modified coal gangue ceramsite and the 5-10mm ordinary coal gangue ceramsite separately to remove surface dust, fine powder, and other impurities. Afterward, allow them to air dry naturally, controlling the surface moisture content of the aggregate to ≤3% to prevent problems such as bleeding, segregation, and clogging during later mixing.

[0032] Simultaneously carry out premixing of cementitious materials: Based on the soil quality of the slope at the engineering site, the regional climate, and the environmental protection and carbon reduction requirements, select an appropriate cementitious material scheme, accurately weigh each component of Scheme 1 or Scheme 2, put them into the mixer and dry mix at a uniform speed for 3 minutes to ensure that the powder is mixed evenly, and prepare homogeneous cement-coal gangue micro powder system cementitious powder and phosphogypsum-based system cementitious powder respectively.

[0033] S2. Dry mixing process: First, put the coarse and fine aggregates into a forced mixer and dry mix for 1 minute to ensure even mixing.

[0034] Subsequently, according to the preset low-carbon cementitious material scheme, the cementitious powder prepared according to Scheme 1 or Scheme 2 is added to the mixer, and dry mixing is continued for 2 minutes to make the cementitious powder evenly adhere to the surface of the aggregate.

[0035] In some implementations, if it is necessary to add slow-release nitrogen, phosphorus, and potassium fertilizers and pH adjusters, the weighed slow-release nitrogen, phosphorus, and potassium fertilizers and humic acid-based pH adjusters can be added simultaneously with the gelling powder and mixed evenly with it, without the need for secondary addition later.

[0036] S3. Wet mixing process: After the dry mixing process is completed, the pre-weighed polycarboxylate-based high-efficiency water-reducing agent, polyacrylamide-based water-retaining agent, and mixing water are added simultaneously. Wet mixing is continued for 3-4 minutes, and the mixing status is observed in real time. The overall mixture has no aggregate leakage, no powder clumping, and no segregation or bleeding. Finally, a low-carbon vegetation concrete mixture with excellent workability, intact pore structure, and suitable for prefabrication is obtained.

[0037] S4. Mold forming: The low-carbon planted concrete mixture is poured into a standardized engineering mold and formed by light vibration for 1-2 minutes using a 50Hz vibration table. Then, the surface of the component is manually scraped and smoothed to ensure a neat appearance and uniform dimensions.

[0038] S5, Curing and Hardening: After the integral casting of the component is completed, it is transferred to a standard curing room for centralized curing. The temperature of the curing environment is 20±2℃ and the humidity is ≥90%. After curing for 24 hours, it is demolded and then cured for another 28 days to finally obtain a hardened low-carbon vegetation concrete component.

[0039] The low-carbon vegetated concrete components prepared above, after standard curing to 28 days, exhibit a compressive strength of 2.5–3 MPa. Their moderate structural bearing capacity meets the basic mechanical requirements for slope protection, soil stabilization, and anti-sliding applications, while avoiding excessive strength that could lead to internal pore blockage. This provides favorable structural conditions for the successful root development and growth of plants. The porosity of the low-carbon vegetated concrete components is 30%–35%, with a well-developed and interconnected pore structure, providing excellent water and air permeability.

[0040] In terms of ecological application effects, the low-carbon vegetated concrete components have excellent vegetation adaptability. After sowing and covering with soil, the overall survival rate of vegetation in the early stage is ≥85%, and the ecological greening effect is significant.

[0041] In terms of erosion resistance and durability, after a simulated rainstorm erosion test lasting 30 minutes, the low-carbon vegetation concrete component maintains its overall structural integrity with an overall mass loss of ≤5%, demonstrating excellent resistance to water erosion and making it suitable for long-term use in complex outdoor working conditions such as rain, water proximity, and strong winds.

[0042] In terms of low-carbon environmental protection and emission reduction, low-carbon vegetated concrete components use a composite low-carbon cementitious system to replace the traditional high-carbon pure cement system, resulting in significant emission reduction benefits. Specifically, when using Scheme 1, compared to a pure cement concrete system under the same working conditions, overall carbon emissions can be reduced by 38%–45%; when using Scheme 2, a phosphogypsum system with superior low-carbon performance, overall carbon emissions are reduced by 55%–62%, demonstrating significant green and low-carbon advantages, high solid waste resource utilization rate, and meeting the current requirements for ecological engineering and green building materials development.

[0043] The following specific embodiments illustrate the low-carbon vegetation concrete, concrete components made from low-carbon vegetation concrete, and their preparation methods provided by the present invention: Example 1: S1. Weigh out each component shown in Table 1 based on the finished product of low-carbon vegetated concrete per cubic meter.

[0044] Table 1. Components and their contents of the low-carbon vegetation concrete provided in Example 1

[0045] The coarse and fine aggregates are sieved separately to remove dust and debris, and then dried until the moisture content is ≤3%.

[0046] The cementitious material selection scheme 1 provided in this embodiment 1 involves dry mixing 42.5 grade ordinary Portland cement and coal gangue powder for 3 minutes until uniform.

[0047] S2. First, put the coarse and fine aggregates into a forced mixer and dry mix for 1 minute to mix evenly. Then, add the above-prepared cementitious material, nitrogen, phosphorus and potassium slow-release fertilizer and humic acid and mix together. Continue to dry mix for 2 minutes.

[0048] S3. Add polycarboxylate superplasticizer, polyacrylamide water-retaining agent and mixing water, and wet mix for 3-4 minutes until the aggregate surface is evenly coated with a thin slurry, with no exposed aggregate and no clumping, to obtain the planted concrete mixture.

[0049] S4. Mold forming: Pour the planted concrete mixture into a customized engineering mold, and use a 50Hz vibration table to gently vibrate for 1~2 minutes to form the concrete, and smooth the surface.

[0050] S5. Curing and hardening: After molding, place in a standard curing room (temperature 20±2℃, humidity ≥90%) for 24 hours to demold, and continue curing for 28 days to obtain hardened planted concrete component E1.

[0051] Tests showed that the 28-day compressive strength of the planted concrete component E1 was 2.9 MPa, the carbon emission reduction rate was 42%, and the plant survival rate was 85%.

[0052] Example 2: Compared with Example 1, the only difference in Example 2 is the composition and content of the low-carbon vegetation concrete. The specific composition and content are shown in Table 2 below.

[0053] Table 2. Components and their contents of the low-carbon vegetation concrete provided in Example 2

[0054] The remaining preparation steps are the same as in Example 1, and will not be repeated here. The hardened vegetated concrete component E2 was finally obtained. Testing showed that the 28-day compressive strength of the vegetated concrete component E2 was 2.7 MPa, the carbon emission reduction rate was 44%, and the plant survival rate was 86%.

[0055] Example 3: Compared with Example 1, Example 3 differs in the components and their contents of the low-carbon vegetation concrete, as well as the preparation scheme of the cementitious material. In Example 3, the cementitious material is prepared using Scheme 2, and the specific components and contents are shown in Table 3 below.

[0056] Table 3. Components and their contents of the low-carbon vegetation concrete provided in Example 3

[0057] In preparation step S1, modified phosphogypsum, S95 grade slag powder, and ordinary silicate cement are dry-mixed for 3 minutes until homogeneous. The remaining preparation steps are the same as in Example 1 and will not be repeated here. The resulting hardened vegetated concrete component E3 is then obtained. Testing showed that the 28-day compressive strength of the vegetated concrete component E3 is 2.8 MPa, the carbon emission reduction rate is 58%, and the plant survival rate is 89%.

[0058] Example 4: Compared with Example 3, Example 4 differs in the components and their contents of the low-carbon vegetation concrete. The specific components and contents are shown in Table 4 below.

[0059] Table 4. Components and their contents of the low-carbon vegetation concrete provided in Example 4

[0060] The remaining preparation steps are the same as in Example 3, and will not be repeated here. The hardened vegetated concrete component E4 was finally obtained. Testing showed that the 28-day compressive strength of the vegetated concrete component E4 was 2.6 MPa, the carbon emission reduction rate was 61%, and the plant survival rate was 90%.

[0061] Comparative Example: S1. Weigh out each component shown in Table 5 based on the finished product of conventional vegetated concrete per cubic meter.

[0062] Table 5. Components and their contents of conventional vegetated concrete provided in the comparative examples.

[0063] The coarse and fine aggregates are sieved separately to remove dust and debris, and then dried until the moisture content is ≤3%.

[0064] S2. First, put the coarse and fine aggregates into the forced mixer and dry mix for 1 minute to mix evenly. Then, add the 42.5 grade ordinary Portland cement and mix together, and continue to dry mix for 2 minutes.

[0065] S3. Add polycarboxylate superplasticizer, polyacrylamide water-retaining agent and mixing water, and wet mix for 3-4 minutes until the aggregate surface is evenly coated with a thin slurry, with no exposed aggregate and no clumping, to obtain the planted concrete mixture.

[0066] S4. Mold forming: Pour the planted concrete mixture into a customized engineering mold, and use a 50Hz vibration table to gently vibrate for 1~2 minutes to form the concrete, and smooth the surface.

[0067] S5. Curing and hardening: After molding, place in a standard curing room (temperature 20±2℃, humidity ≥90%) for 24 hours to demold, and continue curing for 28 days to obtain the hardened planted concrete component P1.

[0068] Tests showed that the 28-day compressive strength of the vegetated concrete component P1 was 6.5 MPa, the carbon emission reduction rate was 0, and the plant survival rate was 51%.

[0069] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A low-carbon vegetated concrete, characterized in that, include: The low-carbon vegetated concrete contains aggregates, cementitious materials, admixtures, and mixing water. The aggregates include coarse aggregates and fine aggregates. In each cubic meter of the low-carbon vegetated concrete, the coarse aggregate content is 720–750 kg, and the coarse aggregate is modified coal gangue ceramsite with a particle size of 5–25 mm. The fine aggregate content is 160–190 kg, and the fine aggregate is ordinary coal gangue ceramsite with a particle size of 5–10 mm or the modified coal gangue ceramsite. The cementitious material can be any one of the following: Option 1: In each cubic meter of the low-carbon vegetation concrete, the total amount of the cementitious material is 95-105 kg, and the cementitious material includes 42-48 kg of ordinary Portland cement and 52-58 kg of coal gangue powder, wherein the particle size of the coal gangue powder is ≤75 μm. Option 2: In each cubic meter of the low-carbon vegetation concrete, the total amount of the cementitious material is 90-100 kg, and the cementitious material includes: 65-72 kg of modified phosphogypsum, 22-28 kg of slag powder and 3-5 kg ​​of the ordinary Portland cement. The admixtures include polycarboxylate superplasticizer and polyacrylamide water-retaining agent. In each cubic meter of the low-carbon vegetation concrete, the dosage of the polycarboxylate superplasticizer is 0.18-0.22 kg, and the dosage of the polyacrylamide water-retaining agent is 0.12-0.18 kg. The amount of mixing water added to each cubic meter of the low-carbon vegetation concrete is 40-45 kg.

2. The low-carbon vegetation concrete according to claim 1, characterized in that, The admixtures also include slow-release nitrogen, phosphorus, and potassium fertilizers and pH adjusters. The amount of slow-release nitrogen, phosphorus, and potassium fertilizers is 0.007% to 0.01% of the total mass of the cementitious material; the amount of pH adjusters is 0.003% to 0.005% of the total mass of the cementitious material.

3. The low-carbon vegetation concrete according to claim 2, characterized in that, The pH adjuster is humic acid.

4. A method for preparing a low-carbon, vegetation-supported concrete component, characterized in that the steps include... include: The aggregate, the cementitious material, the admixture and the mixing water are weighed according to the formula of the low-carbon vegetation concrete provided by any one of claims 1 to 3. The coarse aggregate and the fine aggregate are sieved separately and dried until the surface moisture content is ≤3%; at the same time, according to the selected scheme, the components corresponding to Scheme 1 or Scheme 2 are dry-mixed for 3 minutes to obtain a uniform gel powder. The coarse aggregate and the fine aggregate are put into a mixer and dry-mixed for 1 minute. Then the gelling powder is added and the mixture is dry-mixed for another 2 minutes to make the gelling powder evenly adhere to the surface of the aggregate. The polycarboxylate-based high-efficiency water-reducing agent, the polyacrylamide-based water-retaining agent, and the mixing water are added simultaneously and mixed wet for 3-4 minutes to obtain a low-carbon vegetation concrete mixture. The low-carbon vegetation concrete mixture is poured into a mold and then cured until hardened to obtain the low-carbon vegetation concrete component.

5. The method for preparing low-carbon vegetation concrete components according to claim 4, characterized in that, The admixtures also include slow-release nitrogen, phosphorus, and potassium fertilizers and a pH adjuster. The amount of the slow-release nitrogen, phosphorus, and potassium fertilizers is 0.007% to 0.01% of the total mass of the cementitious material; the amount of the pH adjuster is 0.003% to 0.005% of the total mass of the cementitious material. When adding the gelling powder, the slow-release nitrogen, phosphorus, and potassium fertilizer and the pH adjuster are added simultaneously.

6. The method for preparing low-carbon vegetation concrete components according to claim 4, characterized in that, After the low-carbon vegetation concrete mixture is poured into the mold, it is gently vibrated on a vibrating table for 1 to 2 minutes to form the shape, and the surface is smoothed. The vibration frequency is 50 Hz.

7. The method for preparing low-carbon vegetation concrete components according to claim 4, characterized in that, The curing conditions are: curing temperature 20±2℃, curing humidity ≥90%.

8. The method for preparing low-carbon vegetation concrete components according to claim 4, characterized in that, The coarse aggregate is modified coal gangue ceramsite with a particle size of 5-25mm. The coarse aggregate is made from cylindrical modified coal gangue sintered ceramsite with a diameter of 10mm and a length of 15-25mm. A double-roll crusher is used to perform single-pass light crushing of the cylindrical modified coal gangue sintered ceramsite with a roller gap of 11mm and a machine speed of 350r / min.

9. A low-carbon, vegetation-supported concrete component, characterized in that, It is prepared by the method for preparing low-carbon vegetation concrete components according to any one of claims 4 to 8.

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