Cement-based impact-wear-resistant environment-friendly material and preparation method thereof

Abstract

The invention discloses a cement-based impact-wear-resistant environment-friendly material and a preparation method thereof.The preparation method comprises the steps that a proper amount of cement, a superfine mineral admixture, a nanoscale admixture, cast stone powder, rubber powder, a composite additive, basalt sand, carborundum and an expanding agent are mixed and stirred, and a first dry mixture is obtained; adding steel fibers into the first dry mixture, and stirring to obtain a second dry mixture; adding water into the second dry mixture, and continuously stirring to obtain a wet mixture; polypropylene fibers, Ecc fibers and steel fibers are mixed with the wet mixture, and the cement-based impact-wear-resistant environment-friendly material is obtained. Various properties of the existing material can be improved.

Description

Technical Field

[0001] This application belongs to the technical field of environmental protection materials, and specifically relates to a cement-based erosion-resistant environmental protection material and a preparation method thereof. Background Art

[0002] In hydropower projects, water discharge structures such as water discharge tunnels, stilling basins, and spillways are often subjected to strong water flow scouring, resulting in structural damage. The thin layers on the surfaces of structures such as aqueducts, channels, and port terminals in water conservancy projects, as well as parts such as slag scouring channels, ore bins, storage bins, cement, and cylindrical silos, hoppers, and storage bin walls in metallurgy, mining, and other systems, are also prone to corrosion, spalling, and scouring damage. To address these problems, the commonly used repair materials are ordinary cement mortar and epoxy mortar. However, ordinary cement mortar has problems such as low bonding strength, poor freeze-thaw cycle resistance, poor wear resistance, poor impermeability, and poor impact resistance, and repeated repairs are likely to occur. Although epoxy mortar has good bonding strength and durability, the construction conditions are relatively strict, the construction speed is slow, and the cost is high.

[0003] Therefore, there is an urgent need to develop more efficient, economical, and durable repair and reinforcement materials to improve the quality and efficiency of engineering repairs. Summary of the Invention

[0004] Aiming at the deficiencies in the prior art, the purpose of this application is to provide a cement-based erosion-resistant environmental protection material and a preparation method thereof. Through precise control of the component ratio and the adoption of innovative preparation processes, this application can achieve the improvement of the performance of existing cement-based erosion-resistant environmental protection materials.

[0005] To achieve the above purpose, this application provides the following technical solutions:

[0006] A cement-based erosion-resistant environmental protection material, by mass, the material includes: cement: 80 to 120 parts; ultrafine mineral admixture: 20 to 30 parts; nano-level admixture: 10 to 15 parts; steel fiber: 45 to 55 parts; Ecc fiber: 15 to 25 parts; polypropylene fiber: 2 to 4 parts; cast stone powder: 8 to 12 parts; rubber powder: 6 to 10 parts; composite additive: 8 to 12 parts; basalt sand: 30 to 40 parts; emery: 80 to 100 parts; expansion agent: 5 to 10 parts.

[0007] Optionally, the ultrafine mineral admixture includes: ultrafine fly ash, 2000-mesh ore powder, and 2000-mesh kaolin, wherein the mass ratio of the ultrafine fly ash, 2000-mesh ore powder, and 2000-mesh kaolin is 0.75:1:0.5.

[0008] Optionally, the nano-level admixture includes: nano-aluminum oxide, nano-silicon dioxide, nano-titanium dioxide, and nano-clay, wherein the mass ratio of the nano-aluminum oxide, nano-silicon dioxide, nano-titanium dioxide, and nano-clay is 0.5:0.3:0.1:0.2.

[0009] Optionally, the composite additive includes: bio-based nano-cellulose, modified starch, and polycarboxylate water reducer, wherein the mass ratio of the bio-based nano-cellulose, modified starch, and polycarboxylate water reducer is 1:0.5:1.

[0010] This application also provides a preparation method of a cement-based erosion-resistant and environmentally friendly material, and the preparation method includes: mixing an appropriate amount of cement, ultrafine mineral admixture, nano-level admixture, cast stone powder, rubber powder, composite additive, basalt sand, emery, and expansion agent to obtain a first dry mixture; adding steel fibers to the first dry mixture and stirring to obtain a second dry mixture; adding water to the second dry mixture and continuing to stir to obtain a wet mixture; mixing polypropylene fibers, Ecc fibers, and steel fibers with the wet mixture to obtain a cement-based erosion-resistant and environmentally friendly material.

[0011] Optionally, the mixed cement, ultrafine mineral admixture, nano-level admixture, cast stone powder, rubber powder, composite additive, basalt sand, emery, and expansion agent are stirred at a low speed.

[0012] Optionally, before stirring, the ultrafine mineral admixture and the nano-level admixture are subjected to surface modification treatment.

[0013] Optionally, the water-binder ratio of the second dry mixture to water is 0.32.

[0014] Optionally, water is added to the second dry mixture in stages for stirring.

[0015] Optionally, the polypropylene fibers, Ecc fibers, and steel fibers are pre-prepared into fiber bundles or fiber meshes and then mixed with the wet mixture.

[0016] Compared with the prior art, the beneficial effects brought by this application are: this application provides a new cement-based environmentally friendly material and its preparation method. By precisely controlling the composition ratio and adopting an innovative preparation process, this application has significantly improved the performance of existing cement-based erosion-resistant and environmentally friendly materials, not only solving the problems of low bonding strength and poor freeze-thaw cycle resistance existing in traditional repair materials, but also reducing costs and improving the quality and efficiency of engineering repair. Description of the Drawings

[0017] Figure 1 is a schematic flowchart of a preparation method of a cement-based erosion-resistant and environmentally friendly material provided by an embodiment of this application. Detailed Embodiments

[0018] Specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. Although specific embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present application can be more thoroughly understood and the scope of the present application can be fully conveyed to those skilled in the art.

[0019] It should be noted that certain terms are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different terms to refer to the same component. The specification and claims do not use the difference in terms as a way to distinguish components, but use the difference in the functions of components as the criterion for distinction. As used throughout the specification and claims, the terms "comprising" or "including" are open-ended terms and should be interpreted as "including but not limited to". The subsequent description in the specification is a preferred embodiment for implementing the present application, but the description is for the purpose of the general principles of the specification and is not intended to limit the scope of the present application. The scope of protection of the present application shall be determined by the scope defined by the appended claims.

[0020] For the convenience of understanding the embodiments of the present application, the following will further explain with specific embodiments as examples in conjunction with the accompanying drawings, and each accompanying drawing does not constitute a limitation to the embodiments of the present application.

[0021] In an exemplary embodiment, the present application provides a cement-based abrasion-resistant and environmentally friendly material. By mass, the material includes: cement: 80 to 120 parts; ultrafine mineral admixture: 20 to 30 parts; nano-level admixture: 10 to 15 parts; steel fiber: 45 to 55 parts; Ecc fiber: 15 to 25 parts; polypropylene fiber: 2 to 4 parts; cast stone powder: 8 to 12 parts; rubber powder: 6 to 10 parts; composite additive: 8 to 12 parts; basalt sand: 30 to 40 parts; emery: 80 to 100 parts; expansive agent: 5 to 10 parts.

[0022] Figure 1 is a schematic flow chart of a preparation method of a cement-based abrasion-resistant and environmentally friendly material provided by an exemplary embodiment of the present application, as Figure 1 shown, the preparation method includes the following steps:

[0023] S1: Add 80 parts of cement, 20 parts of ultrafine mineral admixture, 10 parts of nano-level admixture, 8 parts of cast stone powder, 6 parts of rubber powder (0.5mm or 1mm gradation), 8 parts of composite additive, 30 parts of basalt sand, 80 parts of emery and 5 parts of expansive agent into a mixing pot, mix and stir at a low speed (for example, 30 rpm) for 2 minutes to obtain a first dry mixture;

[0024] In this step, before stirring, the surface of the ultra-fine mineral admixture and the nano-level admixture needs to be modified, and the rubber powder needs to be activated.

[0025] Among them, the surface modification of the ultra-fine mineral admixture or the nano-level admixture includes the following steps:

[0026] First, disperse the ultra-fine mineral admixture or the nano-level admixture in a solvent (such as water) to form a uniform suspension;

[0027] Second, add an appropriate amount of polymerizable monomer (such as acrylate) to the suspension, and add an appropriate amount of initiator (such as benzoyl peroxide, diisopropylbenzene peroxide or azobisisobutyronitrile, so as to effectively initiate the polymerization reaction and ensure that the polymerizable monomer can be fully polymerized on the surface of the ultra-fine mineral admixture or nano-level admixture), and stir well and then heat at an appropriate temperature for a period of time to promote the polymerization reaction of the polymerizable monomer on the surface of the ultra-fine mineral admixture or the nano-level admixture, thereby forming a uniform and stable polymer coating layer. By forming a polymer coating layer, the agglomeration phenomenon between the ultra-fine mineral admixture or nano-level admixture particles can be effectively prevented, which helps the ultra-fine mineral admixture or nano-level admixture to be more uniformly dispersed in the cement matrix, thereby improving the performance of the final product; in addition, the polymer coating layer can also enhance the bonding strength between the ultra-fine mineral admixture or nano-level admixture and the cement matrix, and can provide better physical or chemical connection between the ultra-fine mineral admixture or nano-level admixture particles and the cement matrix, making the overall structure of the final product more stable.

[0028] Finally, wash the ultra-fine mineral admixture or the nano-level admixture with polymer coating layer formed with deionized water to remove the unreacted polymerizable monomer and by-products, and then perform drying treatment.

[0029] In addition, the activation treatment of the rubber powder includes the following steps:

[0030] First, use a silane coupling agent to perform preliminary surface treatment on the rubber powder (dissolve the selected silane coupling agent in an appropriate solvent (such as ethanol, water, etc.) to prepare a solution with a certain concentration. The solution concentration needs to be adjusted according to the actual situation to ensure that enough active groups can react with the surface of the rubber powder; disperse the rubber powder evenly in the above silane coupling agent solution and react under specific conditions for a period of time so that the silane coupling agent can form chemical bonds on the surface of the rubber powder, usually by reacting a functional group in the silane coupling agent with the active sites on the rubber surface), to increase its hydrophilicity and improve the compatibility and bonding force between the rubber powder and the cement matrix;

[0031] Secondly, immerse the rubber powder after preliminary surface treatment in a solution containing a specific coupling agent (such as titanate coupling agent or aluminate coupling agent) so that the specific coupling agent forms a first layer of film on the surface of the rubber powder;

[0032] Next, repeat the impregnation - rinsing process, each time using different functional materials (such as plasticizers, anti - aging agents, etc.) to construct a multi - layer film structure on the surface of the rubber powder;

[0033] Finally, after completing the assembly of all layers, perform cleaning and drying to ensure that each layer is firmly attached to the surface of the rubber powder.

[0034] After activation treatment, the rubber powder can not only better integrate into the cement matrix, but also improve its own stability and durability, thus helping to extend the service life of the final product.

[0035] In summary, whether it is the surface modification treatment of the ultrafine mineral admixture and nano - level admixture or the activation treatment of the rubber powder in this application, the purpose is to optimize the interaction between materials at the microscopic level and then improve the performance of the final product.

[0036] It should also be noted that the reason for using low - speed stirring for the mixture in this step is that, firstly, it can reduce the dust - raising phenomenon caused by high - speed stirring; secondly, for lightweight materials such as rubber powder, they are prone to floating on the surface or aggregating together under high - speed stirring and are difficult to be evenly dispersed throughout the mixture, while low - speed stirring helps these lightweight components to be more evenly distributed throughout the mixture and avoid agglomeration.

[0037] S2: Add 45 parts of steel fibers to the first dry - mix material and stir for 1 min to obtain a second dry - mix material;

[0038] In this step, it should be noted that steel fibers are relatively fragile. If they are mixed with other components with greater hardness (such as basalt sand, emery, etc.) in step S1, the steel fibers will be damaged or broken, thus affecting their reinforcement effect. By first forming a relatively uniform first dry - mix material environment without hard particles and then adding steel fibers, mechanical damage to the steel fibers can be effectively reduced, thereby protecting their integrity, and further improving the fractional uniformity of the steel fibers in the first dry - mix material, which helps to prepare an environmentally friendly material with better performance.

[0039] S3: Add water to the second dry - mix material according to a water - binder ratio of 0.32 and continue stirring for 2 min to obtain a wet - mix material;

[0040] In this step, the water-cement ratio of 0.32 is the optimal ratio obtained through experiments and precise calculations in this application. Mixing the second dry mixture with this water-cement ratio can minimize the porosity of the final product to the greatest extent and improve the density, thereby helping to enhance the compressive strength and tensile strength of the final product. In addition, the water-cement ratio of this proportion can also reduce the formation of microcracks inside the cement, improve the ability of the final product to resist environmental erosion, and further enhance its durability. If the water-cement ratio is too large (greater than 0.32), first, it will cause an increase in pores in the cement paste, weaken the connection force between particles, and lead to a significant decrease in strength; second, a large amount of pores will be left after excessive water evaporation, increasing the shrinkage risk of the final product and possibly causing problems such as cracking. If the water-cement ratio is too small (less than 0.32), first, the final product will become dry and hard, making it difficult to carry out normal mixing, transportation, and pouring operations; second, the lack of sufficient water will hinder the full hydration reaction of the cement, affect the development of early strength, and may cause problems such as slow growth of later strength.

[0041] In addition, this application adopts a strategy of adding water in stages. First, add 70% of the water (including 0.1% viscosity regulator, such as methylcellulose, hydroxypropyl methylcellulose, or modified starch), and stir at a speed of 400 rpm for 1.5 min; at the same time, monitor through an online viscosity sensor and adjust the addition rate of the remaining 30% of the water in real time, and stir until the target viscosity (1000 cP to 5000 cP. This viscosity range helps to improve the workability of the final product, making it easier to carry out construction operations such as pumping, pouring, and troweling. If the viscosity is too high, it will cause problems such as uneven material distribution or difficulty in filling the formwork; if the viscosity is too low, problems such as bleeding and segregation are likely to occur).

[0042] It should be noted that adding water in stages can ensure that each component is more evenly dispersed in the mixture, and can more effectively activate the reaction potential of cement, ultrafine mineral admixtures, and nano-level admixtures, promote their full contact and reaction with water, and ensure that the reaction can proceed under optimal conditions. This not only helps to enhance the strength and durability of the final product, but also helps to optimize the microstructure of the final product and improve the overall performance. If all the water is added at once, it may cause some materials to not be fully wetted or local over-wetting, thus affecting the quality of the final product.

[0043] In addition, by monitoring with an on-line viscosity sensor and adjusting the addition rate of the remaining moisture according to real-time data (adjusting the addition rate of the remaining 30% water in small increments and gradually, to avoid overshooting caused by excessive adjustment at one time. For example, it can be set to fine-tune the water addition rate every few seconds to a few minutes according to the latest viscosity reading until the viscosity stabilizes within the target viscosity range), it helps to ensure that the environmentally friendly material finally prepared has good fluidity and workability during construction, and avoids affecting the construction efficiency and quality due to too high or too low viscosity.

[0044] It should also be noted that by adding a viscosity regulator to the water, firstly, it can increase the viscosity of the mixture, making it have better fluidity and pumpability, facilitating construction operations such as pumping, pouring, and troweling, and ensuring that the finally prepared material can evenly fill every corner of the formwork; secondly, it helps to maintain the uniform distribution of each component in the mixture, reduce the occurrence of water separation (bleeding) phenomenon, and prevent segregation between the aggregate and the cementitious material. In short, the purpose of adding the viscosity regulator is to solve various problems that may occur during the actual construction process, and at the same time ensure that the cement-based abrasion-resistant environmentally friendly material has excellent work performance and long-term stability.

[0045] S4: Prepare 2 parts of polypropylene fiber, 15 parts of Ecc fiber and 105 parts of steel fiber into a fiber bundle or fiber mesh in advance, and then mix it with the wet mixture, and immediately perform microwave treatment after mixing to accelerate the initial hydration reaction. Among them, the microwave parameters of the microwave treatment can be set as follows: frequency 2.5 GHz, power 500 W, irradiation time 2 min. After the microwave treatment, a cement-based abrasion-resistant environmentally friendly material is obtained.

[0046] In this step, through experiments, directly adding single fibers (that is, directly putting polypropylene fiber, Ecc fiber and steel fiber) into the wet mixture easily leads to fiber aggregation and formation of clusters, which will not only affect the reinforcement effect of the fibers, but also cause insufficient strength in local areas. Preparing into a fiber bundle or fiber mesh in advance helps to ensure that each fiber is more evenly distributed throughout the mixture. In addition, by pre-weaving into a fiber bundle or fiber mesh, the interaction between different types of fibers can be increased, such as physical entanglement and mechanical locking, etc. This structure can more effectively transfer stress, thereby improving the overall mechanical properties of the composite material. Further, the form of the fiber bundle or fiber mesh makes the fiber easier to combine with the wet mixture, can reduce the problems of fiber floating or sedimentation, facilitates construction operations, and can ensure that the fiber will not sink to the bottom due to gravity during construction, thus affecting the performance of the upper layer of the material.

[0047] It should be noted that when the fiber bundle or fiber mesh pre-prepared from polypropylene fiber, Ecc fiber and steel fiber is mixed with the wet mixture and then immediately subjected to microwave treatment, the chemical reaction rate between cement particles and water can be accelerated through the heating effect of microwave, especially the early hydration process, which helps to quickly form more hydration products (such as C-S-H gel), thereby improving the early strength of the final product. And the early high-strength development can promote the formation of a more uniform and fine microstructure in the cement matrix, so that the final product can reach the operable state faster during construction, reduce the formwork support time, and thus improve the construction efficiency. If microwave treatment is not carried out, the early strength development of the cement-based material will be slower, which means that for some time after construction, the final product will not be able to withstand external loads or stresses, increasing the risk of cracking, especially in application scenarios where rapid demolding or load-bearing is required. In addition, microwave treatment can not only accelerate the hydration reaction, but also help the fibers to be better fixed in the cement matrix, avoiding the problems of fiber floating or sedimentation. If microwave treatment is not carried out, the fibers may sink to the bottom due to gravity or aggregate together due to insufficient stirring, affecting the mechanical properties of the final product.

[0048] In another exemplary embodiment, the present application also provides a preparation method of a cement-based erosion-resistant and environmentally friendly material, and the preparation method includes the following steps:

[0049] S10: Add 100 parts of cement, 25 parts of ultrafine mineral admixture, 12 parts of nano-level admixture, 10 parts of cast stone powder, 8 parts of rubber powder (0.5mm or 1mm gradation), 10 parts of composite additive, 35 parts of basalt sand, 90 parts of emery and 7 parts of expansion agent into a stirring pot, mix and stir at a low speed for 3 min to obtain a first dry mixture;

[0050] S20: Add 50 parts of steel fiber to the first dry mixture, and stir for 1 min to obtain a second dry mixture;

[0051] S30: Add water to the second dry mixture according to a water-binder ratio of 0.32 and continue to stir for 2 min to obtain a wet mixture;

[0052] S40: Pre-prepare 3 parts of polypropylene fiber, 20 parts of Ecc fiber and 100 parts of steel fiber into a fiber bundle or fiber mesh, and then mix it with the wet mixture, and immediately carry out microwave treatment after mixing to accelerate the initial hydration reaction. Among them, the microwave parameters of the microwave treatment can be set as follows: frequency 2.5 GHz, power 550 W, irradiation time 3 min. After the microwave treatment is completed, a cement-based erosion-resistant and environmentally friendly material is obtained.

[0053] In another exemplary embodiment, the present application also provides a preparation method of a cement-based erosion-resistant and environmentally friendly material, and the preparation method includes the following steps:

[0054] S100: Add 120 parts of cement, 30 parts of ultrafine mineral admixture, 15 parts of nano-level admixture, 12 parts of blast furnace slag powder, 10 parts of rubber powder (0.5 mm or 1 mm gradation), 12 parts of composite additive, 40 parts of basalt sand, 100 parts of emery and 10 parts of expansive agent into a mixing pan, mix them and stir at a low speed for 4 min to obtain a first dry mixture;

[0055] S200: Add 55 parts of steel fiber into the first dry mixture, and stir for 1 min to obtain a second dry mixture;

[0056] S300: Add water to the second dry mixture according to a water-binder ratio of 0.32 and continue to stir for 2 min to obtain a wet mixture;

[0057] S400: Prepare 4 parts of polypropylene fiber, 25 parts of Ecc fiber and 95 parts of steel fiber into a fiber bundle or fiber mesh in advance, then mix them with the wet mixture, and immediately perform microwave treatment after mixing. The microwave parameters of the microwave treatment can be set as follows: frequency 3 GHz, power 600 W, irradiation time 4 min. After the microwave treatment is completed, a cement-based erosion-resistant and environmentally friendly material is obtained.

[0058] In the above embodiments, through experimental tests, the second embodiment can be used as the optimal embodiment. Specifically, compared with the first embodiment, this embodiment increases the proportions of key components such as cement, ultrafine mineral admixture and nano-level admixture, which helps to enhance the strength and durability of the final product. In addition, the microwave treatment time and power in this embodiment are increased compared with the first embodiment, and this adjustment helps to accelerate the initial hydration reaction and promote the formation of the internal structure of the wet mixture, thereby improving the early strength and development potential of the wet mixture. In addition, this embodiment can effectively control the production cost on the basis of ensuring that the product has excellent mechanical properties and durability. In contrast, although the third embodiment may show more excellent performance under some extreme conditions, the additional cost increase may not be correspondingly rewarded in most application scenarios.

[0059] In the above embodiments, the present application adopts the strategy of adding the steel fibers step by step. Taking the first embodiment as an example for illustration: First, the initial addition in step S2 is to create a basic mixture containing some steel fibers, which helps to provide a relatively uniform dispersion environment for the subsequent addition of more steel fibers. In step S4, in addition to continuously adding the remaining steel fibers, polypropylene fibers and Ecc fibers are also added and pre-prepared in the form of fiber bundles or fiber meshes, so as to ensure that all types of fibers are more evenly distributed in the entire wet mixture, forming an effective three-dimensional reinforcement network structure. Secondly, adding the steel fibers in batches and adjusting the stirring speed and time helps to improve the mixing efficiency and quality. After a small amount of steel fibers are initially added and high-speed stirring is carried out, these fibers can be better embedded in the basic mixture, reducing the occurrence of agglomeration. Before adding a large amount of steel fibers again in step S4, accelerating the initial hydration reaction through microwave treatment can make the mixture reach a certain viscosity, further helping the fibers to maintain a uniform distribution. By adding different amounts of steel fibers in stages and combining the use of other types of fibers (such as polypropylene fibers and Ecc fibers), the present application can maximize the overall mechanical properties of the final product without sacrificing the characteristics of any one fiber. For example, steel fibers mainly provide high strength and toughness, while polypropylene fibers and Ecc fibers help to improve the workability and crack resistance of the material. On the contrary, if all the steel fibers are added in step S2 at one time, since the mixture contains hard particles (such as basalt sand, emery, etc.), if all the steel fibers are added at one time and mixed with these hard particles, the steel fibers are easily damaged or broken due to collision during high-speed stirring, which will significantly reduce their reinforcement effect and weaken the mechanical properties of the final product. Step S4 is the stage after adding water to form a wet mixture. At this time, if a large amount of steel fibers are added at one time, due to the certain fluidity of the wet mixture, the steel fibers are more likely to agglomerate, forming fiber bundles or lumps, rather than being evenly distributed in the mixture, which will lead to a decrease in the fluidity of the final product, resulting in difficulties in pumping or pouring. Moreover, step S4 also includes microwave treatment to accelerate the initial hydration reaction. If too many steel fibers are added at one time, it will change the heat conduction characteristics of the mixture, affect the effect of microwave treatment, and further affect the early strength development and overall performance of the cement matrix.

[0060] In summary, whether all the steel fibers are added at one time in step S2 or in step S4, it may lead to problems such as fiber damage, uneven distribution, increased mixing difficulty, and construction inconvenience, ultimately affecting the overall performance and construction quality of the final product. Therefore, adding the steel fibers in batches in the present application is an effective strategy to ensure the uniform dispersion of the fibers, protect the integrity of the fibers, and optimize the performance of the final product.

[0061] In the above embodiments, the present application innovatively combines cast stone powder and rubber powder. Among them, the high hardness of the cast stone powder endows the cement-based material with excellent wear resistance in a wear environment, enabling it to effectively resist physical wear. The good elasticity and toughness of the rubber powder can not only improve the impact resistance and fatigue resistance of the cement-based material, but also enhance its corrosion resistance and high-temperature resistance to a certain extent. This unique combination utilizes the synergistic effect between the cast stone powder and the rubber powder, making the finally prepared material exhibit a longer service life and more excellent overall performance in complex and harsh working environments.

[0062] In another exemplary embodiment, the present application also provides a method for preparing a cement-based impact and abrasion resistant environmental protection material. Different from the previous embodiment, in this embodiment, industrial solid waste aggregates (such as slag, fly ash, furnace slag or ceramic waste, etc.) are used to replace basalt sand.

[0063] In this embodiment, compared with basalt sand as a natural aggregate, industrial solid waste aggregates have good physical and chemical stability and can provide better performance than basalt sand. For example, slag and fly ash contain active SiO2 and Al2O3, which can react with Ca(OH)2 during the hardening process of concrete to form additional C-S-H gels, thereby enhancing the density and durability of the final product.

[0064] After obtaining the cement-based impact and abrasion resistant environmental protection material based on the above embodiments, the preparation method further includes: placing the cement-based impact and abrasion resistant environmental protection material in a constant temperature oven (25°C), and curing it under a negative pressure environment of -0.05 MPa for 24 h, and then curing it under standard conditions for 7 days.

[0065] In another exemplary embodiment, the ultra-fine mineral admixture includes: ultra-fine fly ash, 2000-mesh mineral powder and 2000-mesh kaolin, and the mass ratio of the ultra-fine fly ash, 2000-mesh mineral powder and 2000-mesh kaolin is 0.75:1:0.5.

[0066] In this embodiment, the ultra-fine fly ash, mineral powder, and kaolin all contain components that can react with the calcium hydroxide (Ca(OH)2) in the cement hydration products. For example, the active SiO2 and Al2O3 contained in the mineral powder and fly ash can react with Ca(OH)2 during the hardening process of concrete to form additional C-S-H gel (Calcium Silicate Hydrate), which can enhance the density and durability of the final product. Kaolin also has relatively high activity and can participate in the secondary reaction of cement to a certain extent, improving the overall performance of the material. In addition, the particle sizes of these three materials are very small, and they can fill the tiny voids in the cement matrix, playing a role in refining the pore structure, thereby improving the microstructure of the material, increasing the density, and enhancing the impermeability and wear resistance. It should be noted that the ratio of 0.75:1:0.5 is the result of a series of experimental optimizations. This ratio aims to balance the synergistic effects among the components and maximize the advantages of each. Specifically: the ultra-fine fly ash helps improve the workability and late-age strength development of the mixture; the 2000-mesh mineral powder can not only increase the strength and durability of the material but also reduce its erosion effect on the cement stone by reacting with Ca(OH)2; the 2000-mesh kaolin helps improve the early strength, and due to its unique crystal structure, it can enhance the crack resistance of the material.

[0067] In another exemplary embodiment, the nano-sized admixtures include: nano-aluminum oxide, nano-silicon dioxide, nano-titanium dioxide, and nano-clay, and the mass ratio of the nano-aluminum oxide, nano-silicon dioxide, nano-titanium dioxide, and nano-clay is 0.5:0.3:0.1:0.2.

[0068] In this embodiment, nano-aluminum oxide has excellent hardness and wear resistance, and at the same time can also improve the high-temperature resistance and mechanical strength of the material. By adding nano-aluminum oxide to the cement-based material, the structural strength and compressive capacity of the material can be enhanced. Nano-silicon dioxide can react with calcium hydroxide (Ca(OH)2) in the cement hydration products to generate more C-S-H gel, thereby improving the density, strength, and durability of the cement-based material. In addition, nano-silicon dioxide can also refine the pore structure and improve the impermeability and chemical corrosion resistance of the material. Nano-titanium dioxide is famous for its photocatalytic activity and has important applications in environmental purification and self-cleaning. Adding nano-titanium dioxide to the cement-based material can not only endow the material with a certain self-cleaning function but also help enhance the anti-ultraviolet aging ability and weather resistance of the material. Nano-clays such as montmorillonite have good thickening, thixotropic, and adsorption properties, and can effectively improve the workability of fresh concrete, such as fluidity and cohesiveness. At the same time, nano-clay can also fill the tiny pores in the cement matrix, further enhancing the density and durability of the material.

[0069] It should be noted that the above ratio is the result of experimental optimization, which aims to balance the synergistic effect between the components, maximize the advantages of each, and ensure the optimization of the overall material performance. Specifically, this ratio can comprehensively improve the mechanical properties, durability and construction performance of cement-based impact-resistant and environmentally friendly materials without significantly increasing costs. For example, an appropriate amount of nano-silica and nano-alumina helps to enhance the structural strength of the material, while nano-titanium dioxide and nano-clay contribute to the weather resistance and working performance of the material. By precisely controlling the ratio of these nanomaterials, the optimal configuration of material performance can be achieved.

[0070] In another exemplary embodiment, the composite additive includes: bio-based nanocellulose, modified starch and polycarboxylate water reducer, and the mass ratio of the bio-based nanocellulose, modified starch and polycarboxylate water reducer is 1:0.5:1.

[0071] In the present embodiment, bio-based nanocellulose, as a reinforcing material, has high strength and high modulus characteristics, and can significantly improve the mechanical properties of cement-based materials, such as tensile strength and toughness. In addition, due to its nanoscale size, it can also be effectively filled in the tiny pores in the cement matrix, which helps to improve the density and durability of the material. Modified starch, as a thickener and water-retaining agent, can increase the workability of fresh concrete, prevent water from being lost too quickly, thereby ensuring the full hydration reaction of cement, not only helping to improve the strength of the final product, but also improving its surface quality and reducing the occurrence of cracks. Polycarboxylic acid-based high-efficiency water-reducing agent can significantly improve the fluidity of concrete without increasing the amount of water used, reduce the water-cement ratio, thereby enhancing the strength and durability of concrete. In addition, it can also effectively reduce the shrinkage rate of concrete and reduce the risk of crack formation.

[0072] It should be noted that the above ratios are determined on the basis of comprehensive consideration of the mechanism of action of each component and its impact on the performance of the final product. Among them, the mass ratio of bio-based nanocellulose to polycarboxylic acid water reducer is set to 1:1, aiming to balance the relationship between the reinforcement effect and fluidity of the material. An appropriate amount of bio-based nanocellulose can provide the necessary mechanical reinforcement, while the polycarboxylic acid water reducer ensures good fluidity and construction performance of the mixture. The proportion of modified starch is relatively low (0.5) because although it is beneficial to improve workability and water retention, excessive use may cause the mixture to be too viscous, which is not conducive to construction operations. By controlling its dosage, the working performance of concrete can be optimized without affecting other properties.

[0073] Next, the present application compares the cement-based material prepared by the method described in the present application with the existing material described in the background art, and the comparison results are shown in Table 1:

[0074] Table 1

[0075]

[0076] As can be seen from Table 1, compared with the existing ordinary cement mortar and epoxy mortar, the cement-based erosion-resistant and environmentally friendly material prepared by the method described in this application performs excellently in all key performance indicators. Especially in terms of compressive strength, flexural strength and durability, it has a significant improvement compared with traditional materials, thus providing a more efficient, economical and durable option for engineering repair.

[0077] The above are only the preferred embodiments of this application, and do not limit the patent scope of this application accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of this application, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of this application.

Claims

1. A cement-based erosion-resistant and environmentally friendly material, characterized in that, By mass parts, the material includes: Cement: 80 to 120 parts; A cement-based erosion-resistant and environmentally friendly material Ultra-fine mineral admixture: 20 to 30 parts; Nanoscale admixture: 10 to 15 parts; Steel fiber: 45 to 55 parts; Ecc fiber: 15 to 25 parts; Polypropylene fiber: 2 to 4 parts; Cast stone powder: 8 to 12 parts; Rubber powder: 6 to 10 parts; Compound additive: 8 to 12 parts; Basalt sand: 30 to 40 parts; Emery: 80 to 100 parts; Expansive agent: 5 to 10 parts.

2. The cement-based erosion-resistant and environmentally friendly material according to claim 1, wherein The ultra-fine mineral admixture includes: Ultra-fine fly ash, 2000-mesh ore powder and 2000-mesh kaolin, wherein, The mass ratio of the ultra-fine fly ash, 2000-mesh ore powder and 2000-mesh kaolin is 0.75:1:0.

5.

3. The cement-based erosion-resistant and environmentally friendly material according to claim 1, wherein The nanoscale admixture includes: Nano-aluminum oxide, nano-silicon dioxide, nano-titanium dioxide and nano-clay, wherein, The mass ratio of the nano-aluminum oxide, nano-silicon dioxide, nano-titanium dioxide and nano-clay is 0.5:0.3:0.1:0.

2.

4. A cement-based erosion-resistant and environmentally friendly material according to claim 1, characterized in that, The compound additive includes: Bio-based nanocellulose, modified starch and polycarboxylate superplasticizer, wherein, The mass ratio of the bio-based nanocellulose, modified starch and polycarboxylate superplasticizer is 1:0.5:

1.

5. A preparation method of a cement-based erosion-resistant and environment-friendly material, characterized in that, The preparation method includes: Mix and stir an appropriate amount of cement, ultra-fine mineral admixture, nanoscale admixture, cast stone powder, rubber powder, compound additive, basalt sand, emery and expansive agent to obtain a first dry mix; Add steel fiber to the first dry mix and stir to obtain a second dry mix; Add water to the second dry mix and continue stirring to obtain a wet mix; Mix polypropylene fiber, Ecc fiber and steel fiber with the wet mix to obtain a cement-based erosion-resistant and environmentally friendly material.

6. The preparation method of a cement-based erosion-resistant and environmentally friendly material according to claim 5, characterized in that, Perform low-speed stirring on the mixed cement, ultra-fine mineral admixture, nanoscale admixture, cast stone powder, rubber powder, compound additive, basalt sand, emery and expansive agent.

7. The preparation method of a cement-based erosion-resistant and environmentally friendly material according to claim 5, characterized in that, Before stirring, perform surface modification treatment on the ultra-fine mineral admixture and the nanoscale admixture.

8. The preparation method of a cement-based erosion-resistant and environmentally friendly material according to claim 5, characterized in that, The water-cement ratio of the second dry mix and water is 0.

32.

9. The preparation method of a cement-based erosion-resistant and environmentally friendly material according to claim 5, characterized in that, Add water to the second dry mix in stages and stir.

10. The preparation method of a cement-based erosion-resistant and environmentally friendly material according to claim 5, characterized in that, Pre-prepare the polypropylene fiber, Ecc fiber and steel fiber into fiber bundles or fiber meshes and then mix them with the wet mix.

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