A coral reef base material and a preparation method, construction method and application thereof

Abstract

The application relates to the technical field of ecological restoration, and discloses a coral reef base material and a preparation method, construction method and application thereof, wherein the coral reef base material comprises the following components in parts by weight: waste concrete matrix 50 parts, cementing material 20-30 parts, cement 1-10 parts, modifier material 20-30 parts, sodium metasilicate 0.1-5 parts, coconut fiber 0.5-5 parts and an ecological coating with a thickness of 0.5-2 cm. The technical scheme provided by the application can improve the ecological restoration potential of the waste concrete matrix, especially in terms of simulating the complexity and diversity of a natural coral reef ecological system.

Description

Technical Field

[0001] This application relates to the field of ecological restoration technology, and in particular to a coral reef substrate material and its preparation method, construction method and application. Background Technology

[0002] Coral reefs, often called the "rainforests of the ocean," support approximately 34% of marine species and are crucial for habitat, reproduction, and foraging. They also protect coastlines and prevent erosion. Although they comprise only 0.07%–0.17% of the ocean area, global climate change and human activities such as rising temperatures, ocean acidification, pollution, and overexploitation have exacerbated coral reef degradation, disrupted ecological balance, and threatened fisheries resources. Global efforts to restore coral reefs have included transplantation initiatives. However, while artificial substrates such as waste concrete matrices can provide attachment points, they cannot fully mimic the complex ecological structure of natural coral reefs, limiting the effectiveness of restoration efforts.

[0003] Therefore, how to enhance the ecological restoration potential of waste concrete matrix, especially in simulating the complexity and diversity of natural coral reef ecosystems, is a technical problem that urgently needs to be solved. Summary of the Invention

[0004] This application provides a coral reef substrate material, its preparation method, construction method, and application, which achieves the technical effect of enhancing the ecological restoration potential of waste concrete substrate, especially in simulating the complexity and diversity of natural coral reef ecosystems.

[0005] To achieve the above objectives, the main technical solutions adopted in this application include:

[0006] In a first aspect, embodiments of this application provide a coral reef substrate material, which comprises the following components in parts by weight: 50 parts waste concrete matrix, 20-30 parts cementitious material, 1-10 parts cement, 20-30 parts modifier material, 0.1-5 parts sodium metasilicate, 0.5-5 parts coconut fiber, and an ecological coating with a thickness of 0.5-2 cm.

[0007] This embodiment provides a coral reef substrate material that effectively enhances the ecological restoration potential of waste concrete substrates by comprehensively utilizing waste concrete matrix, cementitious materials, modifiers, sodium metasilicate, coconut fiber, and an ecological coating, particularly in simulating the complexity and diversity of natural coral reef ecosystems. The reuse of waste concrete matrix not only reduces the environmental burden but also provides a solid foundation for ecological restoration. The improved strength, durability, and stability of the material enable it to persist in the marine environment for extended periods, resisting the impact of water currents and waves. The addition of coconut fiber enhances the substrate's adhesion and microhabitat space, providing an ideal habitat for corals and other marine life. Furthermore, the use of the ecological coating further optimizes the substrate surface's attachment environment, supporting the attachment and growth of corals and other marine organisms, simulating the ecological functions of natural coral reefs. These characteristics collectively promote ecosystem restoration and enhance the possibility of artificial coral reefs evolving into natural ecosystems.

[0008] In one embodiment, the waste concrete matrix is ​​taken from recycled aggregates of construction waste concrete after crushing, and by weight percentage includes the following components: 50-65% coarse aggregate with a particle size of 4.75-30 mm, 35-50% fine aggregate with a particle size of 0.075-4.75 nm, and less than or equal to 3% powder with a particle size of less than 0.075 mm; wherein, the waste concrete matrix is ​​alkaline.

[0009] This embodiment, through its unique composition and structure, significantly enhances ecological restoration potential, particularly in simulating the complexity and diversity of natural coral reef ecosystems. Its alkaline properties help neutralize acidic substances in seawater, mitigating the effects of ocean acidification and promoting calcium carbonate deposition, supporting coral reef growth. Simultaneously, the porous structure of the coarse and fine aggregates in the waste concrete matrix provides abundant attachment sites for marine organisms, mimicking the physical environment of natural coral reefs and contributing to ecosystem restoration and diversity support. Furthermore, the corrosion resistance and long-term stability of the waste concrete matrix enable it to maintain its effectiveness in the marine environment for an extended period, providing a durable habitat for corals and other organisms, further enhancing the ecological restoration effect.

[0010] In one embodiment, the gelling material is composed of a calcium chloride solution, a magnesium chloride solution, and a boric acid solution, or the gelling material is composed of a calcium chloride solution, a magnesium chloride solution, and a sodium alginate solution; wherein...

[0011] The concentration of the calcium chloride solution is 1-4 mol / L;

[0012] The concentration ratio of the magnesium chloride solution to the calcium chloride solution is 1 / 5 to 1 / 20;

[0013] The concentration of the boric acid solution is 0.3-2 mol / L;

[0014] The sodium alginate solution contains 0.3-1.0 wt% sodium alginate.

[0015] The concentration and proportion of the cementitious materials in this embodiment are designed to enhance the ecological restoration potential of the waste concrete matrix, particularly in simulating the complexity and diversity of natural coral reef ecosystems. Calcium chloride solution provides calcium ions that react with carbonate ions to form calcium carbonate, enhancing the matrix's hardness and stability, mimicking a key component of coral reefs. Magnesium ions in magnesium chloride solution further optimize the crystal form of calcium carbonate, improving the matrix's durability and crack resistance, and enhancing its stability in marine environments. Boric acid solution promotes the formation of calcium carbonate crystal nuclei, increasing the matrix's strength and compressive strength, thereby enhancing its long-term reliability. Sodium alginate solution crosslinks with calcium ions to form a three-dimensional gel structure, providing a supporting framework and improving the material's toughness and crack resistance. The synergistic effect of these components gives the waste concrete matrix better biocompatibility, stability, and durability in simulated coral reef ecosystems, ultimately effectively promoting ecosystem restoration and diversity.

[0016] In one embodiment, the cement is grade 42.5R silicate cement.

[0017] The 42.5R grade cement used in this embodiment possesses high early strength, which helps accelerate the hardening process of the waste concrete matrix, ensuring that the repaired structure reaches a stable state in a short time, thus effectively resisting erosion from natural environments such as tides and waves. Secondly, the cement's hydration products (such as hydrated calcium silicate and calcium hydroxide) improve the matrix's strength and durability, enhancing its resistance to seawater corrosion and ensuring the matrix's stability during long-term use. Furthermore, the alkaline environment of the cement helps neutralize acidic substances in seawater, reducing the impact of seawater acidification on coral reef growth, providing better biocompatibility, and further promoting healthy coral reef growth. Therefore, 42.5R silicate cement not only enhances the physical properties of the waste concrete matrix but also improves its ecological function, contributing to more efficient ecological restoration.

[0018] In one embodiment, the modifier material is a sodium carbonate solution with a concentration of 1-4 mol / L.

[0019] This embodiment utilizes a sodium carbonate solution as a modifier, with a concentration ranging from 1 to 4 mol / L, to generate calcium carbonate within a waste concrete matrix. This process not only improves the matrix's mechanical properties, such as compressive and tensile strength, but also enhances its ecological restoration potential, particularly in simulating the complexity and diversity of natural coral reef ecosystems. The generated calcium carbonate, especially aragonite, rapidly dissolves and releases calcium, providing a source of calcium for marine life such as corals and shellfish, thereby accelerating ecosystem recovery. Simultaneously, this calcium carbonate generation mimics natural mineralization processes, contributing to the long-term stability and self-repair of the waste concrete matrix, ultimately promoting the regeneration and biodiversity enhancement of the marine ecosystem.

[0020] In one embodiment, the volume ratio of the cementitious material to the modifier material is 1:(0.8-1.5).

[0021] This embodiment utilizes a reasonable volume ratio of 1:(0.8-1.5), allowing each component to react fully at the optimal proportion, generating stable and dense calcium carbonate crystals, thereby improving the mechanical properties and crack resistance of the matrix material. This design not only optimizes the strength and stability of the material but also possesses good potential for ecological restoration.

[0022] In one embodiment, the coconut fiber has a diameter of 0.1-0.8 mm and a length of 5-30 mm.

[0023] This embodiment, by limiting the fiber size of coconut fiber in waste concrete matrix, significantly enhances its ecological restoration potential, especially in simulating the complexity and diversity of natural coral reef ecosystems. The coconut fiber, by forming a uniformly distributed network structure, improves the mechanical properties and crack resistance of the waste concrete matrix, similar to the biosupport function in coral reefs. Furthermore, the natural degradation properties of coconut fiber help improve the adaptability of the waste concrete matrix in marine environments and provide habitats for aquatic organisms, thereby enhancing its ecological adaptability and restoration capacity. Its diverse fiber structure simulates the multi-layered, multi-species environment of coral reefs, further improving the stability and long-term service life of the concrete. Therefore, coconut fiber not only improves the structural strength of waste concrete matrix but also promotes ecosystem restoration and resource recycling, meeting environmental protection requirements.

[0024] In one embodiment, the ecological coating consists of shell fragments, photosynthetic microalgae spores, and a binder; wherein,

[0025] The particle size of the shell fragments is 0.1 mm to 1 cm;

[0026] The photosynthetic microalgae spores are selected from at least one of Chlorella, Dunaliella, diatoms or marine cyanobacteria;

[0027] The binder is selected from at least one of sodium alginate-calcium crosslinked gel, chitosan, xanthan gum, sodium metasilicate, or calcium phosphate gel.

[0028] The eco-coating in this embodiment, composed of shell fragments, photosynthetic microalgae spores, and a binder, significantly enhances the ecological restoration potential of the substrate material, particularly in simulating the complexity and diversity of natural coral reef ecosystems. The rough surface of the shell fragments provides abundant attachment sites for microorganisms and algae, similar to the structure of coral reefs, contributing to increased biodiversity in the substrate. Photosynthetic microalgae spores, such as Chlorella and diatoms, improve dissolved oxygen levels in the surrounding environment through photosynthesis, promoting healthy ecosystem development. The binder, such as sodium alginate-calcium crosslinked gel or chitosan, enhances the stability and durability of the eco-coating, ensuring stable microalgae growth. The synergistic effect of these three components not only enhances the ecological restoration function of the waste concrete substrate but also simulates the multi-layered biological habitat of natural coral reefs, further increasing the complexity and diversity of the ecosystem.

[0029] In one embodiment, the ratio of the mass of the shell fragments, the mass of the binder, and the wet weight of the photosynthetic microalgae spores is 100:(2-10):(0.1-2); the inoculum size of the photosynthetic microalgae spores is 10. 6 -10 9 cells·g -1 .

[0030] This embodiment ensures that the ecological coating provides sufficient adhesion and stability while providing support and promoting photosynthesis by limiting the ratio of the mass of shell fragments, the mass of the binder, and the wet weight of the photosynthetic microalgae spores to 100:(2-10):(0.1-2). The particles of shell fragments provide attachment sites for microorganisms, similar to the structure of coral reefs, promoting biological attachment and growth. The moderate amount of binder ensures that the ecological coating maintains a stable structure and avoids affecting its breathability and biological attachment performance. An appropriate amount of photosynthetic microalgae spores contributes to photosynthesis, increases dissolved oxygen in the water, and promotes the growth of marine organisms such as coral larvae. Overall, the reasonable component ratio and addition amount not only enhance the physical properties of the ecological coating but also simulate the ecological characteristics of natural coral reefs, improving the ecological restoration function of waste concrete matrix.

[0031] Secondly, embodiments of this application provide a method for preparing the aforementioned coral reef substrate material, comprising:

[0032] Waste concrete matrix, cement, and coconut fiber are mixed evenly in a certain proportion to obtain a solid mixture;

[0033] The cementitious material, the modifier material, and sodium metasilicate are mixed in proportion and stirred evenly to obtain a mixed solution;

[0034] Add the mixed solution to the solid mixture, stir evenly, then put it into a mold, cure at 20-30℃ for 5-10 days, and air dry for 3-5 days to obtain the base material precursor;

[0035] The eco-coating is applied to the surface of the base material precursor according to the required thickness to obtain the coral reef base material.

[0036] This embodiment provides a method for preparing the aforementioned coral reef substrate material. By mixing waste concrete matrix, cement, and coconut fiber in a specific ratio, a stable structural foundation is provided, while the addition of coconut fiber enhances the material's toughness and crack resistance. By mixing cementitious materials, modifiers, and sodium metasilicate into a solution, a calcium carbonate cemented structure similar to that of coral reefs is generated. This not only improves the material's ecological adaptability but also provides ideal attachment sites for marine organisms, especially coral larvae. Finally, by coating the substrate surface with an ecological coating, the material's ecological function is further enhanced, providing a habitat for marine life and promoting the restoration of the marine ecosystem. This material design not only enhances the ecological restoration potential of waste concrete but also successfully simulates the complexity and diversity of natural coral reefs, contributing to the long-term restoration and stability of the marine ecological environment.

[0037] Thirdly, this application provides an application of a coral reef substrate material, wherein the coral reef substrate material described above or the coral reef substrate material prepared by the above preparation method is applied to the ecological restoration of coral reefs.

[0038] Fourthly, embodiments of this application provide a construction method, including:

[0039] Identify the areas of the coral reef that require restoration;

[0040] Combining at least two or more of the coral reef substrate materials described above or the coral reef substrate materials prepared by the preparation methods described above, a composite structure is obtained;

[0041] Coral species that match the environmental characteristics of the area to be restored are transplanted onto the composite structure, and the composite structure after transplanting the coral species is placed into the area to be restored in order to restore the area.

[0042] Specifically, a detailed environmental assessment of the damaged area is necessary before coral reef restoration can begin. This includes water quality analysis, water flow velocity, light conditions, temperature variations, and substrate type. These environmental parameters directly affect coral growth and survival. Based on the environmental assessment results, specific areas to be restored are identified. These areas should have similar environmental characteristics to facilitate unified management and restoration. Before restoration, the current state of the coral reef is monitored and recorded, including coral coverage, species, and health status. This data will serve as a baseline for evaluating the restoration's effectiveness.

[0043] Select at least two different shapes of coral reef substrate material (such as cubes, cylinders, triangular prisms, etc.). Connect the different shaped coral reef substrate materials together using ropes or other fixing methods to form a composite structure. This composite structure can increase the stability and complexity of the coral reef substrate material, providing more habitat space for marine life. Optimize the design of the composite structure according to the specific environmental characteristics of the area to be restored. For example, in areas with strong currents, a more stable structure can be designed; in areas with weak light, more attachment sites can be added.

[0044] Based on the environmental characteristics of the area to be restored, suitable coral species should be selected for transplantation. Different coral species have varying degrees of adaptability to environmental conditions; therefore, it is necessary to select coral species that can thrive in the target environment. Scientific transplantation methods should be employed to ensure the survival rate of the corals. This includes appropriate transplantation time, depth, and density. For example, in areas with weak water flow, the transplantation density can be appropriately increased; in areas with strong sunlight, coral species tolerant of strong light can be selected.

[0045] Based on the environmental assessment results, the composite structure will be deployed to the area to be restored. Deployment should avoid causing damage to the surrounding environment. After deployment, ensure the stability of the composite structure to prevent it from being washed away or moved by water currents. Anchoring or other fixing methods can be used to ensure the stability of the composite structure within the restoration area. Regularly monitor the restoration area, recording coral growth, the types and quantities of attached organisms, etc. Based on the monitoring results, timely maintenance and adjustments will be made to ensure the long-term sustainability of the restoration effect.

[0046] This embodiment provides a construction method that combines at least two different coral reef substrate materials to simulate the diversity and complexity of natural coral reefs, thereby enhancing the ecological restoration potential of waste concrete matrix. The combined structure design provides abundant habitat space for corals and other marine life, enhancing the stability and diversity of the ecosystem. Transplanting coral species that match the environmental characteristics of the area to be restored ensures high coral survival rates and healthy growth, effectively promoting the ecological restoration of the coral reef. Through this method, the waste concrete substrate not only provides structural support but also enhances the ecological function of the restoration area, ensuring long-term restoration effectiveness and sustainability. Attached Figure Description

[0047] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0048] Figure 1 A flowchart illustrating a method for preparing a coral reef substrate material, as provided in this application embodiment. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0050] Coral reef ecosystems, often called the "rainforests of the ocean," play a vital role in the global marine ecosystem. Although coral reefs comprise only 0.07% to 0.17% of the ocean area, they support approximately 34% of marine life species and play a crucial role in the habitat, reproduction, and foraging of marine organisms. Furthermore, coral reefs protect coastlines, mitigate wave impacts, and prevent erosion, directly affecting the livelihoods and safety of coastal residents. Therefore, the health of coral reefs is essential for the overall balance of the marine ecosystem and the sustainable development of human society.

[0051] However, the impacts of global climate change and human activities have posed severe challenges to coral reef ecosystems. Rising ocean temperatures have triggered coral bleaching, causing corals to excrete symbiotic algae and die under high temperatures. Furthermore, ocean acidification, pollution (such as oil spills and plastic pollution), overfishing, and coastal development have exacerbated coral reef degradation. This degradation not only leads to the death of large numbers of corals but also disrupts the marine ecological balance, reduces habitats, impacts the sustainability of fishery resources, and poses a direct threat to human economic activities and quality of life.

[0052] To address this challenge, global coral reef conservation and restoration efforts have been undertaken. Transplanting healthy corals to degraded areas effectively enhances ecosystem biodiversity and stability. However, the success of coral transplantation is closely linked to substrate selection. A suitable substrate is essential for successful coral attachment and growth. While artificial substrates, such as waste concrete matrices, can provide some attachment points, they cannot fully mimic the complex ecological structure of natural coral reefs. Artificial substrates typically lack the biodiversity and functions of natural coral reefs, limiting the growth of transplanted corals and the long-term effectiveness of ecological restoration.

[0053] Therefore, how to enhance the ecological restoration potential of waste concrete matrix, especially in simulating the complexity and diversity of natural coral reef ecosystems, is a technical problem that urgently needs to be solved.

[0054] According to an embodiment of this application, a coral reef substrate material is provided, comprising the following components in parts by weight: 50 parts waste concrete matrix, 20-30 parts cementitious material, 1-10 parts cement, 20-30 parts modifier material, 0.1-5 parts sodium metasilicate, 0.5-5 parts coconut fiber, and an ecological coating with a thickness of 0.5-2 cm.

[0055] Specifically, using waste concrete matrix as the main raw material not only achieves resource reuse but also reduces the environmental impact of construction waste. The addition of cementitious materials, modifiers, and sodium metasilicate significantly improves the material's strength and durability, while enhancing its stability in marine environments. The inclusion of coconut fiber further improves the material's toughness and crack resistance, making it more durable in marine environments. Finally, by applying an eco-friendly coating, the material surface provides abundant attachment sites and microhabitat spaces, promoting the attachment and growth of coral larvae and other marine organisms, significantly improving the ecological restoration effect.

[0056] This embodiment provides a coral reef substrate material that effectively enhances the ecological restoration potential of waste concrete substrates by comprehensively utilizing waste concrete matrix, cementitious materials, modifiers, sodium metasilicate, coconut fiber, and an ecological coating, particularly in simulating the complexity and diversity of natural coral reef ecosystems. The reuse of waste concrete matrix not only reduces the environmental burden but also provides a solid foundation for ecological restoration. The improved strength, durability, and stability of the material enable it to persist in the marine environment for extended periods, resisting the impact of water currents and waves. The addition of coconut fiber enhances the substrate's adhesion and microhabitat space, providing an ideal habitat for corals and other marine life. Furthermore, the use of the ecological coating further optimizes the substrate surface's attachment environment, supporting the attachment and growth of corals and other marine organisms, simulating the ecological functions of natural coral reefs. These characteristics collectively promote ecosystem restoration and enhance the possibility of artificial coral reefs evolving into natural ecosystems.

[0057] In one embodiment, the waste concrete matrix is ​​derived from recycled aggregates obtained from pulverized construction waste concrete, and comprises the following components by weight percentage: 50-65% coarse aggregate with a particle size of 4.75-30 mm, 35-50% fine aggregate with a particle size of 0.075-4.75 nm, and less than or equal to 3% powder with a particle size less than 0.075 mm; wherein the waste concrete matrix is ​​alkaline.

[0058] Specifically, waste concrete matrix is ​​made from recycled aggregates obtained through the crushing and processing of construction waste concrete, including coarse aggregates, fine aggregates, and powder. The main role of coarse aggregates in concrete is load-bearing, especially providing compressive strength. Due to their larger particle size, they can form larger pores, providing better structural support. The addition of coarse aggregates can effectively reduce concrete shrinkage, improving the overall stability and durability of the concrete. Through their larger porosity, coarse aggregates can also allow seawater to permeate and provide attachment space for organisms, which has a positive effect on ecological restoration. Fine aggregates are mainly used to fill the voids between coarse aggregates, increasing the density of the concrete. Fine aggregates not only improve the workability of concrete, making it easier to mix and mold, but also help it form a microporous structure during the molding process, which is conducive to the attachment and growth of microorganisms. For example, the microstructure provided by fine aggregates provides attachment points for marine microorganisms, coral larvae, and other organisms, which is beneficial to ecological restoration. The role of powder is to further fill the pores between fine aggregates, increasing the density of the concrete. The addition of powder materials reduces the porosity of concrete, improving its impermeability and durability. In marine environments, the density of the powder helps reduce water penetration, enhancing the concrete's resistance to corrosion in seawater. Furthermore, the fine particles of the powder improve the concrete surface, providing a smoother surface and reducing the difficulty for harmful organisms such as algae and microorganisms to adhere.

[0059] The pH value of waste concrete matrix is ​​typically between 7 and 14, making it alkaline. This alkaline characteristic gives waste concrete matrix significant ecological functions, especially in the context of ocean acidification. First, ocean acidification is caused by carbon dioxide dissolving in seawater to form carbonic acid, leading to a decrease in seawater pH and consequently damaging coral reefs and marine ecosystems. The alkaline components of waste concrete matrix can effectively neutralize acidic substances in seawater, raising the pH value and thus mitigating the negative impact of ocean acidification on coral reef growth. Second, the alkaline environment promotes calcium carbonate deposition, which is crucial for the normal functioning of coral reef ecosystems. Calcium carbonate is a major component of corals and promotes their growth, attachment, and regeneration. The alkaline environment of waste concrete matrix creates favorable conditions for calcium carbonate deposition. Furthermore, the alkaline properties of waste concrete matrix enhance its corrosion resistance in marine environments. Due to the salinity and microbial activity in seawater, ordinary concrete is easily corroded in marine environments, while alkaline waste concrete matrix provides a stronger protective layer, extending its service life. This makes the application of waste concrete matrix in marine environments sustainable in the long term. Therefore, waste concrete matrix can not only effectively utilize construction waste concrete, but also play a positive role in the protection and restoration of marine ecosystems, especially coral reefs, through its alkaline properties.

[0060] This embodiment, through its unique composition and structure, significantly enhances ecological restoration potential, particularly in simulating the complexity and diversity of natural coral reef ecosystems. Its alkaline properties help neutralize acidic substances in seawater, mitigating the effects of ocean acidification and promoting calcium carbonate deposition, supporting coral reef growth. Simultaneously, the porous structure of the coarse and fine aggregates in the waste concrete matrix provides abundant attachment sites for marine organisms, mimicking the physical environment of natural coral reefs and contributing to ecosystem restoration and diversity support. Furthermore, the corrosion resistance and long-term stability of the waste concrete matrix enable it to maintain its effectiveness in the marine environment for an extended period, providing a durable habitat for corals and other organisms, further enhancing the ecological restoration effect.

[0061] In one embodiment, the gelling material is composed of a calcium chloride solution, a magnesium chloride solution, and a boric acid solution, or the gelling material is composed of a calcium chloride solution, a magnesium chloride solution, and a sodium alginate solution; wherein...

[0062] The concentration of calcium chloride solution is 1-4 mol / L;

[0063] The concentration ratio of magnesium chloride solution to calcium chloride solution is 1 / 5 to 1 / 20;

[0064] The concentration of boric acid solution is 0.3-2 mol / L;

[0065] The sodium alginate solution contains 0.3-1.0 wt% sodium alginate.

[0066] Specifically, calcium ions in calcium chloride solution are key components in the formation of calcium carbonate (CaCO3), a major component of coral reefs. Calcium ions in calcium chloride solution can react with carbonate ions (CO3-). 2- The reaction produces calcium carbonate, providing the basic building blocks for coral reef growth. The concentration of the magnesium chloride solution is 1 / 5 to 1 / 20 that of the calcium chloride solution, and the magnesium ions (Mg²⁺) are present in the solution. 2+ Magnesium ions can regulate the crystal form of calcium carbonate, promoting the formation of high-magnesium calcite (Mg-Calcite) or aragonite. High-magnesium calcite and aragonite have higher stability and solubility, are closer to the composition of natural coral reefs, and are beneficial for coral attachment and growth. Magnesium ions can refine the size of calcium carbonate crystals, making the cementation interface denser and improving the crack resistance and durability of the material. Boric acid solution can promote the formation of calcium carbonate crystal nuclei and accelerate the calcium carbonate deposition process by adjusting the ionic environment of the cementing material solution. Boric acid solution can improve the stability of calcium carbonate crystal nuclei, making them less soluble in marine environments. Boric acid solution can improve the mechanical properties of the matrix material, increasing its compressive strength and crack resistance. The carboxyl groups in sodium alginate solution can crosslink with calcium ions to form a gel network. This gel network can provide a nucleation template for calcium carbonate deposition, allowing calcium carbonate crystals to be evenly distributed in the matrix material. The sodium alginate gel network can improve the stability and durability of the matrix material, making it less prone to breakage or cracking in marine environments. Sodium alginate is a natural biopolymer with good biocompatibility and will not cause toxicity or negative effects on marine life.

[0067] Therefore, these components interact and exert a synergistic effect in the waste concrete matrix. Calcium ions in the calcium chloride solution combine with carbonate ions to form calcium carbonate crystals. The formation of calcium carbonate crystals promotes the stability and growth of the waste concrete matrix. Calcium ions in the calcium chloride solution crosslink with carboxyl groups in sodium alginate to form a stable gel network. This network can fix calcium carbonate crystal nuclei and promote their uniform distribution. Magnesium ions in the magnesium chloride solution can regulate the crystal form of calcium carbonate, making it closer to the composition of natural coral reefs, while refining the crystal size and improving the material's density and crack resistance. Boric acid solution can promote the formation and stabilization of calcium carbonate crystal nuclei by regulating the ionic environment, accelerating the calcium carbonate deposition process.

[0068] The concentration and proportion of the cementitious materials in this embodiment are designed to enhance the ecological restoration potential of the waste concrete matrix, particularly in simulating the complexity and diversity of natural coral reef ecosystems. Calcium chloride solution provides calcium ions that react with carbonate ions to form calcium carbonate, enhancing the matrix's hardness and stability, mimicking a key component of coral reefs. Magnesium ions in magnesium chloride solution further optimize the crystal form of calcium carbonate, improving the matrix's durability and crack resistance, and enhancing its stability in marine environments. Boric acid solution promotes the formation of calcium carbonate crystal nuclei, increasing the matrix's strength and compressive strength, thereby enhancing its long-term reliability. Sodium alginate solution crosslinks with calcium ions to form a three-dimensional gel structure, providing a supporting framework and improving the material's toughness and crack resistance. The synergistic effect of these components gives the waste concrete matrix better biocompatibility, stability, and durability in simulated coral reef ecosystems, ultimately effectively promoting ecosystem restoration and diversity.

[0069] In one embodiment, the cement is grade 42.5R silicate cement.

[0070] Specifically, silicate cement is cement with calcium silicate as its main component. It is typically made from raw materials such as limestone and clay through high-temperature calcination, and possesses high strength and good durability. Silicate cement reacts with water to produce hydration products such as hydrated calcium silicate (CSH gel) and calcium hydroxide (CH), which impart strength and durability to the cement paste. 42.5R indicates that the cement has a 28-day compressive strength of not less than 42.5 MPa and high early strength (R stands for "early strength"). 42.5R silicate cement acts as a binder in waste concrete matrices, binding the aggregates, cementitious materials, and other components together to form a matrix material with a certain strength. The hydration products of silicate cement improve the durability of the matrix material, enabling it to withstand long-term corrosion and impact in marine environments. The release of calcium hydroxide during the hydration process of silicate cement makes the matrix material alkaline, which helps reduce the impact of seawater acidification on coral reef growth.

[0071] The 42.5R grade cement used in this embodiment possesses high early strength, which helps accelerate the hardening process of the waste concrete matrix, ensuring that the repaired structure reaches a stable state in a short time, thus effectively resisting erosion from natural environments such as tides and waves. Secondly, the cement's hydration products (such as hydrated calcium silicate and calcium hydroxide) improve the matrix's strength and durability, enhancing its resistance to seawater corrosion and ensuring the matrix's stability during long-term use. Furthermore, the alkaline environment of the cement helps neutralize acidic substances in seawater, reducing the impact of seawater acidification on coral reef growth, providing better biocompatibility, and further promoting healthy coral reef growth. Therefore, 42.5R silicate cement not only enhances the physical properties of the waste concrete matrix but also improves its ecological function, contributing to more efficient ecological restoration.

[0072] In one embodiment, the modifier material is a sodium carbonate solution with a concentration of 1-4 mol / L.

[0073] Specifically, within a concentration range of 1-4 mol / L, the supply of carbonate ions is sufficient to react fully with calcium ions in the calcium chloride solution to form calcium carbonate. Calcium carbonate is an important component of waste concrete matrix, and its quantity and quality directly affect the performance of the matrix material. The crystal form of calcium carbonate may differ at different concentrations. Generally, lower concentrations may favor the formation of calcite crystals, while higher concentrations may promote the formation of aragonite or high-magnesium calcite. These different crystal forms of calcium carbonate possess different physical and chemical properties, such as hardness, solubility, and stability. For example, aragonite has relatively low hardness but high solubility, making it suitable for the rapid formation of bioavailable calcium carbonate in marine environments. Furthermore, the concentration of the sodium carbonate solution significantly affects the mechanical properties of the matrix material. Within a concentration range of 1-4 mol / L, an appropriate amount of carbonate ions can promote the formation and filling of calcium carbonate, improving the material's density and thus enhancing compressive strength. An appropriate amount of carbonate ions can also improve the material's toughness and increase tensile strength. This is because the formation of calcium carbonate crystals can fill microcracks in the material, reduce stress concentration, and thus improve the tensile properties of the material.

[0074] This embodiment utilizes a sodium carbonate solution as a modifier, with a concentration ranging from 1 to 4 mol / L, to generate calcium carbonate within a waste concrete matrix. This process not only improves the matrix's mechanical properties, such as compressive and tensile strength, but also enhances its ecological restoration potential, particularly in simulating the complexity and diversity of natural coral reef ecosystems. The generated calcium carbonate, especially aragonite, rapidly dissolves and releases calcium, providing a source of calcium for marine life such as corals and shellfish, thereby accelerating ecosystem recovery. Simultaneously, this calcium carbonate generation mimics natural mineralization processes, contributing to the long-term stability and self-repair of the waste concrete matrix, ultimately promoting the regeneration and biodiversity enhancement of the marine ecosystem.

[0075] In one embodiment, the volume ratio of the cementitious material to the modifier material is 1:(0.8-1.5).

[0076] Specifically, it mainly consists of calcium chloride solution, magnesium chloride solution, boric acid solution, and sodium alginate solution. Its main function is to generate calcium carbonate through a chemical reaction, providing the primary cementing component for the matrix material and enhancing its strength and stability. The modifier material is mainly sodium carbonate solution. Its function is to react with calcium chloride to generate calcium carbonate, while simultaneously regulating the ionic environment during the reaction process, promoting the formation of calcium carbonate crystal nuclei and crystal growth, and improving the microstructure of the matrix material. A volume ratio of 1:(0.8-1.5) ensures that the molar ratio of sodium carbonate to calcium chloride is within a reasonable range, thereby guaranteeing the complete reaction and generating sufficient calcium carbonate to provide good cementing properties. Magnesium chloride is used in the reaction to regulate the crystal form and size of calcium carbonate, promoting the formation of high-magnesium calcite / aragonite and refining the deposits. An appropriate volume ratio ensures that magnesium chloride plays its optimal role in the reaction system, thereby generating dense and crack-resistant calcium carbonate crystals. Boric acid solution promotes the formation of calcium carbonate crystal nuclei by regulating the ionic environment, while sodium alginate solution provides a nucleation template for calcium carbonate deposition by cross-linking calcium ions with its carboxyl groups to form a gel network.

[0077] This embodiment utilizes a reasonable volume ratio of 1:(0.8-1.5), allowing each component to react fully at the optimal proportion, generating stable and dense calcium carbonate crystals, thereby improving the mechanical properties and crack resistance of the matrix material. This design not only optimizes the strength and stability of the material but also possesses good potential for ecological restoration.

[0078] In one embodiment, the coconut fiber has a diameter of 0.1-0.8 mm and a length of 5-30 mm.

[0079] Specifically, coconut fiber can act as a bridge between waste concrete matrix particles, improving the material's crack resistance and overall stability. In marine environments, matrix materials are affected by water flow and biological activity. Coconut fiber can effectively reduce material breakage and cracking under these external forces, extending the material's service life. A fiber diameter in the range of 0.1-0.8 mm ensures uniform distribution of the coconut fiber within the matrix material, forming an effective network structure. This network structure enhances the material's toughness and crack resistance. Smaller fiber diameters (e.g., 0.1 mm) better bond with waste concrete matrix particles, forming a good interfacial connection. Larger fiber diameters (e.g., 0.8 mm) provide stronger bridging, enhancing the material's overall stability. Fiber lengths in the range of 5-30 mm effectively bridge waste concrete matrix particles, forming a stable network structure. Longer fibers (e.g., 30 mm) provide stronger bridging, enhancing the material's overall stability. Longer fibers can better disperse stress, reducing crack propagation. When the material is subjected to external forces, the fibers can absorb some energy, preventing further crack propagation, thereby improving the material's crack resistance.

[0080] This embodiment, by limiting the fiber size of coconut fiber in waste concrete matrix, significantly enhances its ecological restoration potential, especially in simulating the complexity and diversity of natural coral reef ecosystems. The coconut fiber, by forming a uniformly distributed network structure, improves the mechanical properties and crack resistance of the waste concrete matrix, similar to the biosupport function in coral reefs. Furthermore, the natural degradation properties of coconut fiber help improve the adaptability of the waste concrete matrix in marine environments and provide habitats for aquatic organisms, thereby enhancing its ecological adaptability and restoration capacity. Its diverse fiber structure simulates the multi-layered, multi-species environment of coral reefs, further improving the stability and long-term service life of the concrete. Therefore, coconut fiber not only improves the structural strength of waste concrete matrix but also promotes ecosystem restoration and resource recycling, meeting environmental protection requirements.

[0081] In one embodiment, the eco-coating consists of shell fragments, photosynthetic microalgae spores, and an adhesive; wherein...

[0082] The particle size of the shell fragments is 0.1 mm to 1 cm;

[0083] The photosynthetic microalgae spores are selected from at least one of Chlorella, Dunaliella, diatoms, or marine cyanobacteria;

[0084] The binder is selected from at least one of sodium alginate-calcium crosslinked gel, chitosan, xanthan gum, sodium metasilicate, or calcium phosphate gel.

[0085] Specifically, the shell fragments, with a particle size ranging from 0.1mm to 1cm, can provide attachment sites of varying sizes to meet the needs of marine organisms of different sizes. The rough surface of the shell fragments can mimic the texture of the natural seabed, providing a more natural habitat for marine life. Furthermore, it is a natural material, environmentally friendly, and will not cause pollution. Chlorella is a single-celled green algae with rapid reproduction and efficient photosynthetic capabilities. It can quickly form a stable biofilm in the early stages, providing an attachment substrate for other organisms. Dunaliella salina is a halophilic algae that can survive and reproduce in high-salt environments, making it suitable for use in marine environments. Diatoms have a siliceous shell, providing stable attachment sites, and their photosynthesis can increase local dissolved oxygen. Marine cyanobacteria are prokaryotes capable of photosynthesis, possessing strong adaptability and survival capabilities, and can survive in various marine environments. The gel formed by the cross-linking of sodium alginate and calcium ions has good biocompatibility and stability, providing a stable growth environment for microalgal spores. Chitosan has good biocompatibility and antibacterial properties, enhancing the stability and durability of the ecological coating. Xanthan gum exhibits excellent adhesion and stability, enhancing the adhesion and durability of eco-coatings. Sodium metasilicate hydrolyzes in aqueous solution to form silica colloids, possessing good adhesion and bonding properties, significantly increasing the viscosity of mixed solutions and improving the bonding effect between waste concrete matrix particles. Calcium phosphate gels demonstrate good biocompatibility and stability, providing a stable growth environment for microalgae spores while enhancing the mechanical properties of eco-coatings.

[0086] Therefore, eco-coatings can provide attachment sites for coral larvae and other marine organisms, promoting their growth and settlement. They mimic the texture and roughness of the natural seabed, providing microhabitats for marine life. Photosynthetic microalgal spores within the eco-coating can perform photosynthesis, secreting extracellular polysaccharides, increasing local dissolved oxygen, and improving the ecological environment. Adhesives enhance the stability and durability of the eco-coating, preventing it from peeling off.

[0087] The eco-coating in this embodiment, composed of shell fragments, photosynthetic microalgae spores, and a binder, significantly enhances the ecological restoration potential of the substrate material, particularly in simulating the complexity and diversity of natural coral reef ecosystems. The rough surface of the shell fragments provides abundant attachment sites for microorganisms and algae, similar to the structure of coral reefs, contributing to increased biodiversity in the substrate. Photosynthetic microalgae spores, such as Chlorella and diatoms, improve dissolved oxygen levels in the surrounding environment through photosynthesis, promoting healthy ecosystem development. The binder, such as sodium alginate-calcium crosslinked gel or chitosan, enhances the stability and durability of the eco-coating, ensuring stable microalgae growth. The synergistic effect of these three components not only enhances the ecological restoration function of the waste concrete substrate but also simulates the multi-layered biological habitat of natural coral reefs, further increasing the complexity and diversity of the ecosystem.

[0088] In one embodiment, the ratio of the mass of the shell fragments, the mass of the binder, and the wet weight of the photosynthetic microalgae spores is 100:(2-10):(0.1-2); the inoculum size of the photosynthetic microalgae spores is 10. 6 -10 9 cells·g -1 .

[0089] Specifically, adding a binder at a concentration between 2 and 10 ensures sufficient adhesion and stability of the eco-coating without excessively affecting its breathability and bioattachment properties. An appropriate amount of binder forms a uniform gel network, enhancing the bonding force between shell fragments and improving the overall performance of the eco-coating. Adding photosynthetic microalgae spores at a concentration between 0.1 and 2 ensures a moderate density of photosynthetic microalgae in the eco-coating, enabling effective photosynthesis while avoiding excessive competition for light and nutrients. An appropriate amount of photosynthetic microalgae spores forms a stable biofilm, providing a good attachment substrate for other marine organisms and promoting their attachment and growth. An appropriate inoculation amount of photosynthetic microalgae spores ensures uniform distribution within the eco-coating, facilitating effective photosynthesis, increasing local dissolved oxygen, and promoting the attachment and growth of coral larvae.

[0090] This embodiment ensures that the ecological coating provides sufficient adhesion and stability while providing support and promoting photosynthesis by limiting the ratio of the mass of shell fragments, the mass of binder, and the wet weight of photosynthetic microalgae spores to 100:(2-10):(0.1-2). The particles of shell fragments provide attachment sites for microorganisms, similar to the structure of coral reefs, promoting biological attachment and growth. The moderate amount of binder ensures that the ecological coating maintains a stable structure and avoids affecting its breathability and biological attachment performance. An appropriate amount of photosynthetic microalgae spores contributes to photosynthesis, increases dissolved oxygen in the water, and promotes the growth of marine organisms such as coral larvae. Overall, the reasonable component ratio and addition amount not only enhance the physical properties of the ecological coating but also simulate the ecological characteristics of natural coral reefs, improving the ecological restoration function of waste concrete matrix.

[0091] Figure 1 A flowchart of a method for preparing a coral reef substrate material provided in this application embodiment includes:

[0092] Step S1: Mix the waste concrete matrix, cement and coconut fiber in a uniform ratio to obtain a solid mixture;

[0093] Step S3: Mix the cementitious material, modifier material, and sodium metasilicate in proportion and stir evenly to obtain a mixed solution;

[0094] Step S5: Add the mixing solution to the solid mixture, stir evenly, then put it into a mold, cure at 20-30℃ for 5-10 days, and air dry for 3-5 days to obtain the base material precursor;

[0095] Step S7: Apply an ecological coating to the surface of the base material precursor according to the thickness requirements to obtain the coral reef base material.

[0096] Specifically, waste concrete matrix, as the main raw material, provides the main structure of the substrate material. The particle size distribution and alkalinity of its recycled aggregates contribute to improving the material's stability and resistance to seawater acidification. Cement, as a cementing material, enhances the matrix's adhesion and strength, ensuring the material's long-term stability in marine environments. Fibers improve the material's toughness and crack resistance, while also being environmentally friendly due to their natural degradation in marine environments. Mechanical mixing ensures uniform distribution of all components, forming a homogeneous solid mixture. The cementing material consists of calcium chloride solution, magnesium chloride solution, boric acid solution, or sodium alginate solution. Calcium chloride solution reacts with sodium carbonate to form calcium carbonate, the main cementing component of the matrix. Magnesium chloride solution is used to regulate the crystal form and size of calcium carbonate, while boric acid and sodium alginate solutions promote calcium carbonate deposition by adjusting the ionic environment and forming a gel network. Sodium carbonate solution reacts with calcium chloride to form calcium carbonate, while simultaneously regulating the ionic environment during the reaction process to optimize calcium carbonate crystal growth. Sodium metasilicate hydrolyzes in aqueous solution to form silica colloid, which has excellent adhesion and bonding properties. This significantly increases the viscosity of the mixed solution, improves the bonding effect between particles in the waste concrete matrix, and enhances the material's durability and impact resistance. Stirring ensures thorough mixing of all components to form a homogeneous solution. The solid-liquid mixture is poured into a mold to form a base material of a predetermined shape. The shape of the mold (e.g., cube, cylinder, triangular prism) can be selected according to actual application requirements, or a biomimetic design can be used to better simulate the natural environment. Curing is carried out at 20-30℃ for 5-10 days to ensure complete chemical reaction and the formation of a stable calcium carbonate cemented structure. The curing time directly affects the material's strength and stability. Natural drying for 3-5 days further improves the material's strength and durability. The natural drying process helps reduce internal moisture in the material, improving its corrosion resistance.

[0097] The eco-coating consists of shell fragments, photosynthetic microalgae spores, and a binder. Shell fragments provide attachment sites and simulate the roughness of a natural environment; photosynthetic microalgae spores increase local dissolved oxygen through photosynthesis, promoting bioattachment; and binders (such as sodium alginate-calcium crosslinking gel, chitosan, xanthan gum, sodium metasilicate, and calcium phosphate gels) enhance the stability and adhesion of the eco-coating. The eco-coating is applied uniformly to the surface of the substrate precursor using spraying or roller coating methods, with a thickness of 0.5-2 cm. Uniform coating is crucial for ensuring the functionality of the eco-coating. The eco-coating not only provides attachment sites and microhabitat space but also improves the local ecological environment through photosynthesis by photosynthetic microalgae, promoting the attachment and growth of coral larvae and other marine organisms.

[0098] This embodiment provides a method for preparing the aforementioned coral reef substrate material. By mixing waste concrete matrix, cement, and coconut fiber in a specific ratio, a stable structural foundation is provided, while the addition of coconut fiber enhances the material's toughness and crack resistance. By mixing cementitious materials, modifiers, and sodium metasilicate into a solution, a calcium carbonate cemented structure similar to that of coral reefs is generated. This not only improves the material's ecological adaptability but also provides ideal attachment sites for marine organisms, especially coral larvae. Finally, by coating the substrate surface with an ecological coating, the material's ecological function is further enhanced, providing a habitat for marine life and promoting the restoration of the marine ecosystem. This material design not only enhances the ecological restoration potential of waste concrete but also successfully simulates the complexity and diversity of natural coral reefs, contributing to the long-term restoration and stability of the marine ecological environment.

[0099] To better explain and facilitate understanding of this application, a detailed description of its specific embodiments is provided below. Unless otherwise specified, all quantities in the embodiments refer to parts by weight, and all raw materials used in the embodiments of this application were purchased commercially.

[0100] Example 1

[0101] The coral reef substrate material in this embodiment is made from the following raw materials: 50 parts of waste concrete matrix (coarse aggregate accounts for 58% of the total mass, fine aggregate accounts for 40% of the total mass, and powder accounts for 2% of the total mass), 20 parts of cementitious material (composed of a 2 mol / L calcium chloride solution, a 0.2 mol / L magnesium chloride solution, and a 1 mol / L boric acid solution), 5 parts of cement, 30 parts of a 2 mol / L sodium carbonate solution, 0.5 parts of sodium metasilicate, 0.5 parts of coconut fiber (fiber diameter 0.1 mm, length 5 mm), and a 0.5 cm thick ecological coating (0.5 cm of shell fragments; photosynthetic microalgae spores including Chlorella and Dunaliella salina, and an inoculum amount of 10). 6 cells•g -1The binder includes sodium alginate-calcium crosslinked gel, chitosan, and xanthan gum; the ratio of the mass of shell fragments, the mass of the binder, and the wet weight of photosynthetic microalgal spores is 100:5:0.2. The volume ratio of the cementitious material to the modifier material is 1:1.

[0102] Preparation method of coral reef substrate material:

[0103] Preparation of solid mixture: Coarse aggregate, fine aggregate, powder, cement and coconut fiber are mixed evenly in proportion to obtain solid mixture.

[0104] Preparation of mixed solution: The cementitious material, the modifier material and sodium metasilicate are mixed in proportion and stirred evenly to obtain a mixed solution.

[0105] Mixing process: Slowly add the mixed solution to the solid mixture and stir thoroughly until homogeneous to form a solid-liquid mixture.

[0106] Mold casting and curing: Pour the solid-liquid mixture into a mold with dimensions of 100×100×100mm. 3 The cube mold and the cylindrical mold with a diameter of 100×200mm were placed in a static curing environment at 25℃ for 7 days.

[0107] Natural drying: After the curing process is completed, the sample is taken out and allowed to air dry at room temperature for 5 days to obtain the coral reef substrate material.

[0108] Example 2

[0109] The coral reef substrate material in this embodiment is made from the following raw materials: 50 parts of waste concrete matrix (coarse aggregate accounts for 50% of the total mass, fine aggregate accounts for 35% of the total mass, and powder accounts for 1% of the total mass), 20 parts of cementitious material (composed of a 4 mol / L calcium chloride solution, a 0.8 mol / L magnesium chloride solution, and a 1 wt% sodium alginate solution), 10 parts of cement, 20 parts of a 1 mol / L sodium carbonate solution, 0.1 parts of sodium metasilicate, 2 parts of coconut fiber (fiber diameter 0.8 mm, length 30 mm), and a 2 cm thick ecological coating (1 cm of shell fragments; the inoculum of photosynthetic microalgae spores includes diatoms, marine cyanobacteria, and the inoculum amount of photosynthetic microalgae spores is 10). 7 cells•g -1 The binder includes sodium metasilicate and calcium phosphate gels; the ratio of the mass of shell fragments, the mass of the binder, and the wet weight of photosynthetic microalgae spores is 100:2:0.1. The volume ratio of the cementitious material to the modifier material is 1:0.8.

[0110] Preparation method of coral reef substrate material:

[0111] Preparation of solid mixture: Coarse aggregate, fine aggregate, powder, cement and coconut fiber are mixed evenly in proportion to obtain solid mixture.

[0112] Preparation of mixed solution: The cementitious material, the modifier material and sodium metasilicate are mixed in proportion and stirred evenly to obtain a mixed solution.

[0113] Mixing process: Slowly add the mixed solution to the solid mixture and stir thoroughly until homogeneous to form a solid-liquid mixture.

[0114] Mold casting and curing: Pour the solid-liquid mixture into a mold with dimensions of 100×100×100mm. 3 The cube mold and the cylindrical mold with a diameter of 100×200mm were placed in a static curing environment at 20℃ for 10 days.

[0115] Natural drying: After the curing process is completed, the sample is taken out and allowed to air dry at room temperature for 4 days to obtain the coral reef substrate material.

[0116] Example 3

[0117] The coral reef substrate material in this embodiment is made from the following raw materials: 50 parts of waste concrete matrix (coarse aggregate accounts for 65% of the total mass, fine aggregate accounts for 50% of the total mass, and powder accounts for 3% of the total mass), 30 parts of cementitious material (composed of a 1 mol / L calcium chloride solution, a 0.05 mol / L magnesium chloride solution, and a 0.3 mol / L boric acid solution), 1 part of cement, 25 parts of a 4 mol / L sodium carbonate solution, 5 parts of sodium metasilicate, 5 parts of coconut fiber (fiber diameter 0.5 mm, length 10 mm), and a 1 cm thick ecological coating (0.1 mm of shell fragments; the inoculum of photosynthetic microalgae spores, including marine cyanobacteria, and the inoculum amount of photosynthetic microalgae spores is 10). 9 cells•g -1 The binder includes sodium alginate-calcium crosslinked gel; wherein the ratio of the mass of shell fragments, the mass of the binder, and the wet weight of photosynthetic microalgal spores is 100:10:2. The volume ratio of the cementitious material to the modifier material is 1:1.5.

[0118] Preparation method of coral reef substrate material:

[0119] Preparation of solid mixture: Coarse aggregate, fine aggregate, powder, cement and coconut fiber are mixed evenly in proportion to obtain solid mixture.

[0120] Preparation of mixed solution: The cementitious material, the modifier material and sodium metasilicate are mixed in proportion and stirred evenly to obtain a mixed solution.

[0121] Mixing process: Slowly add the mixed solution to the solid mixture and stir thoroughly until homogeneous to form a solid-liquid mixture.

[0122] Mold casting and curing: Pour the solid-liquid mixture into a mold with dimensions of 100×100×100mm. 3 The cube mold and the cylindrical mold with a diameter of 100×200mm were placed in a static curing environment at 30℃ for 5 days.

[0123] Natural drying: After the curing process is completed, the sample is taken out and allowed to air dry at room temperature for 3 days to obtain the coral reef substrate material.

[0124] Comparative Example 1

[0125] Same as Example 1, except that no eco-friendly coating is applied.

[0126] Comparative Example 2

[0127] Same as Example 1, except that the gelling material does not contain magnesium chloride solution.

[0128] Comparative Example 3

[0129] Same as Example 2, except that sodium metasilicate was not added.

[0130] Comparative Example 4

[0131] Same as Example 3, except that no coconut flakes were added.

[0132] Comparative Example 5

[0133] Same as Example 1, except that no eco-friendly coating is applied, and only pure water is sprayed.

[0134] The coral reef substrate materials prepared in Examples 1-3 and Comparative Examples 1-5 were evaluated. The compressive strength was measured using cubic specimens (100×100×100mm). 3 The tensile strength was tested according to GB / T50081-2019; the splitting tensile strength was tested using cylindrical specimens (Φ100×200mm) also according to GB / T50081-2019. The performance statistics of the above coral reef substrate materials are shown in Table 1:

[0135]

[0136] As shown in Table 1, Comparative Example 1 exhibits higher compressive strength and splitting tensile strength under the synergistic effect of magnesium chloride, boric acid and sodium metasilicate, which are 23.5±1.8MPa and 2.8±0.2MPa, respectively, indicating that the combination can effectively improve the overall performance of the matrix.

[0137] Comparative Example 2, lacking the addition of magnesium chloride, resulted in insufficient interfacial compactness, leading to a decrease in strength to 19.2 ± 2.0 MPa and 2.4 ± 0.1 MPa, indicating that Mg... 2+Its key role in crystal form regulation and interface enhancement.

[0138] Comparative Example 3 lacked sodium metasilicate, resulting in significantly insufficient bonding strength of the matrix, with the strength further reduced to 17.8±1.5MPa and 1.9±0.2MPa. This indicates that sodium metasilicate is the core component for improving bonding performance and crack resistance.

[0139] Comparative Example 4, without the addition of coconut fiber, lacked the bridging and crack passivation effect of the fiber, and its strength decreased to 20.6±1.7MPa and 2.1±0.3MPa, indicating the important role of fiber in improving crack resistance and toughness.

[0140] Examples 1 to 3 not only maintained good mechanical properties, indicating a synergistic reinforcing effect between the eco-coating and the substrate. In contrast, Comparative Example 5, which was sprayed with only pure water (23.5 ± 1.6 MPa, 2.7 ± 0.2 MPa) and had no eco-coating, still maintained a strength level close to that of the standard system, which was superior to Comparative Examples 2, 3, and 4, which lacked key components.

[0141] In summary, magnesium chloride, sodium metasilicate, and coconut fiber all significantly improve the mechanical properties of the matrix. The eco-coating not only provides ecological functions but also further enhances strength performance. The coral reef substrate material prepared in this application achieves compressive strengths that meet and exceed the requirements of C20 concrete while reducing cement usage, thus possessing the dual advantages of being green, low-carbon, and ecologically restorative.

[0142] The coral reef substrate materials prepared in Example 1 and Comparative Example 5 were evaluated. After being placed in a marine environment for one year, the samples were removed, and the bioattachment index (P, kg / m²) was calculated within a sampling area of ​​100 mm × 100 mm according to the following formula. 2 The bioattachment index (H′) and the Shannon-Wiener index (H′) are used to assess the diversity of the bioattachment community on the sample surface. A higher value indicates better bioattachment.

[0143]

[0144]

[0145]

[0146] Where m is the dry matter of the attached organisms, in kg; s is the sampling area, in m². 2 ;P iis the ratio of the number of the i-th type of attached organism to the total number of attached organisms; S is the number of species of attached organisms.

[0147] The performance statistics of the above coral reef substrate materials are shown in Table 2:

[0148]

[0149] As shown in Table 2, the bio-adhesion index of Example 1 under the action of the ecological coating is 17.5 ± 2.6 kg / m³. 2 The value was almost twice that of Comparative Example 5, and its Shannon-Wiener index was 2.47±0.21, significantly higher than that of Comparative Example 5 (1.52±0.17). This indicates that the ecological coating can significantly improve the quality and community diversity of organisms attached to the sample surface.

[0150] The Chlorella in the ecological coating forms a stable biofilm through rapid early reproduction, while shell fragments provide a rough structure and attachment sites. Calcium phosphate glue, as an inorganic binding matrix, enhances the stability of the surface layer, thereby promoting an increase in the number of attached organisms and improving species diversity.

[0151] In contrast, Comparative Example 5, which only sprayed pure water, lacked an ecologically inducing coating, resulting in a lower number of attached organisms and a simpler community structure, with ecological functions far inferior to Example 1. The combined results further validate the crucial role of the ecological coating in enhancing the ecological restoration potential of waste concrete matrix.

[0152] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0153] The above description is merely an embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this application should be included within the scope of the claims of this application.

[0154] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method of making a coral reef substrate material, characterized by, The preparation method comprises the following steps: a solid mixture is obtained by uniformly mixing, in parts by weight, 50 parts of waste concrete substrate, 1-10 parts of cement and 0.5-5 parts of coconut fiber; the waste concrete substrate is alkaline; the waste concrete substrate is obtained from recycled aggregate of crushed construction waste concrete; a mixed solution is obtained by uniformly mixing 20-30 parts of cementing material, 20-30 parts of modifier material, and 0.1-5 parts of sodium metasilicate; the cementing material is composed of calcium chloride solution, magnesium chloride solution and boric acid solution, or the cementing material is composed of calcium chloride solution, magnesium chloride solution and sodium alginate solution; the concentration of the calcium chloride solution is 1-4 mol / L; the concentration ratio of the magnesium chloride solution to the calcium chloride solution is 1 / 5-1 / 20; the concentration of the boric acid solution is 0.3-2 mol / L; the mass fraction of sodium alginate in the sodium alginate solution is 0.3-1.0 wt%; the modifier material is sodium carbonate solution, and the concentration of the sodium carbonate solution is 1-4 mol / L; the volume ratio of the cementing material to the modifier material is 1:(0.8-1.5); the mixed solution is added to the solid mixture and stirred uniformly, and then the mixture is placed in a mold and cured at a temperature of 20-30 °C for 5-10 days and naturally dried for 3-5 days to obtain a base material precursor; an ecological coating layer is coated on the surface of the base material precursor to a thickness of 0.5-2 cm to obtain a coral reef base material; the ecological coating layer is composed of shell debris, photosynthetic microalgae spores and a binder; the particle size of the shell debris is 0.1 mm-1 cm; the photosynthetic microalgae spores are selected from at least one of Chlorella, Dunaliella and Diatom; the binder is selected from at least one of sodium alginate-calcium cross-linked gel, chitosan, xanthan gum, sodium metasilicate or calcium phosphate gel; The ratio between the mass of the shell fragments, the mass of the binder and the wet weight of the photosynthetic microalgal spores is 100:(2-10):(0.1-2); the inoculum of the photosynthetic microalgal spores is 10 6 -10 9 cells•g -1 .

2. The production method according to claim 1, characterized by, the waste concrete substrate comprises, in percentage by weight, the following components: coarse aggregate with a particle size of 4.75-30 mm, 50-65%; fine aggregate with a particle size of 0.075-4.75 nm, 35-50%; and powder with a particle size less than 0.075 mm, less than or equal to 3%.

3. The preparation method according to claim 1, characterized in that, The cement is Portland cement of grade 42.5R.

4. The method of claim 1, wherein, The coconut fiber has a fiber diameter of 0.1-0.8 mm and a length of 5-30 mm.

5. Use of a coral reef substrate material, characterized in that, The coral reef base material prepared by the preparation method of any one of claims 1-4 is used for ecological restoration of coral reefs.

6. A construction method, characterized by The method comprises the following steps: an area to be restored of a coral reef is obtained; at least two coral reef base materials prepared by the preparation method of any one of claims 1-4 are combined to obtain a combined structure; coral species matching the environmental characteristics of the area to be restored are transplanted on the combined structure, and the combined structure after the transplantation of the coral species is put into the area to be restored to restore the area to be restored.

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