A cementitious material for multi-aggregate curing, its preparation method and application

Abstract

This invention relates to the field of cementitious materials for emergency repairs in road and civil engineering, specifically a cementitious material for multi-aggregate curing, its preparation method, and its application. The method includes the following steps: S1, uniformly mixing an inorganic cementitious matrix, a slow-release setting regulator, and a dispersion regulator to obtain a dry powder matrix; S2, adding solid epoxy resin powder, a moisture-responsive core-shell modified amine curing agent, and an organosilane hybrid modified anti-corrosion filler to the dry powder matrix and stirring to obtain the cementitious material. This invention achieves on-demand slow release of active amines through a moisture-responsive core-shell modified amine curing agent, combined with organosilane hybrid modified anti-corrosion filler to construct a long-lasting anti-corrosion barrier and impart self-healing capabilities to micro-cracks, forming a synergistic closed-loop mechanism of "moisture regulation - ion capture - defect repair." The product is adaptable to aggregates with different moisture contents, significantly improving the density, impermeability, and salt corrosion resistance of the cured body, fully meeting the engineering needs for emergency repairs and long-term corrosion resistance under complex working conditions.

Description

Technical Field

[0001] This invention relates to the field of cementitious materials for emergency repair of roads and civil engineering, specifically to a cementitious material for solidification of multiple aggregates, its preparation method, and its application. Background Technology

[0002] In engineering scenarios such as emergency road repair, base reinforcement, marine structure repair, and prefabricated joint grouting, cementitious materials need to be quickly mixed with on-site aggregates of complex origins and with significant differences in physical properties to achieve early load-bearing strength. However, existing conventional cementitious systems face the following prominent technical bottlenecks in practical engineering applications: Firstly, the moisture content of aggregates (such as recycled aggregates and sea sand) fluctuates drastically on-site. Traditional systems often use a fixed water-cement ratio, which cannot dynamically compensate for changes in adsorbed water on the aggregate surface and free water in the pores. This leads to an imbalance in the effective water-cement ratio, causing setting dispersion, false setting, bleeding, and uneven early strength development, which seriously restricts the stability of construction performance and the homogeneity of the cured network.

[0003] Secondly, while inferior or highly absorbent aggregates such as sea sand and recycled aggregates are increasingly widely used, they are rich in corrosive media such as chloride ions and sulfate ions, and have a loose microstructure and weak interfacial transition zone. Conventional anti-corrosion admixtures mostly rely on simple physical addition, which makes it difficult to form a long-lasting and dense protective barrier at the aggregate-slurry interface. This allows corrosive ions to easily penetrate the matrix, inducing steel corrosion and expansion cracking, resulting in a sharp drop in long-term durability.

[0004] Third, rapid-setting cementitious materials often rely on high-temperature steam curing, which is energy-intensive and easily induces surface micro-cracks; while room-temperature curing results in slow early hydration kinetics, making it difficult to meet the emergency requirement of "rapidly opening to traffic within 2 hours". Conventional setting modifiers and curing agents lack a spatiotemporal synergistic mechanism, which can easily lead to false setting, bleeding, or later strength reduction, thus restricting the construction efficiency in complex working conditions.

[0005] In summary, there is an urgent need in this field for a cementitious material preparation method that can adapt to the moisture content of aggregates, simultaneously construct an interfacial corrosion barrier, and utilize the system's self-heating to achieve rapid densification at low temperatures, so as to fundamentally solve the technical pain points of fluctuating construction performance and insufficient durability in multi-aggregate applications. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of this invention is to provide a cementitious material for multi-aggregate curing and its preparation method.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A method for preparing a cementitious material for multi-aggregate curing includes the following steps: S1. Dry powder matrix premixing: By mass, take 75-138 parts of inorganic cementitious matrix, 0.05-1 parts of slow-release setting agent and 0.2-2 parts of dispersion regulating agent, mix at room temperature at a speed of 150-200 r / min for 3-5 min, and pass through an 80 mesh sieve to obtain dry powder matrix; S2, Functional component compounding: Add 3-8 parts of solid epoxy resin powder, 1.2-3.2 parts of moisture-responsive core-shell modified amine curing agent and 3-8 parts of organosilane hybrid modified anti-corrosion filler to the dry powder matrix obtained in step S1, and mix at room temperature at a speed of 200-300 r / min for 5-10 min to obtain the gelling material. The preparation method of the moisture-responsive core-shell modified amine curing agent includes the following steps: S11. By weight, mix 20-40 parts of modified fatty amine curing agent with 50-70 parts of polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol block copolymer solution, and emulsify at high speed of 2500-3500 rpm for 10-20 minutes in a water bath at 65-75℃ to form a stable oil / water emulsion. S12. Slowly add 2.5-4.5 parts of functional monomer solution and 0.5-1.5 parts of potassium persulfate solution to the oil / water emulsion. Under nitrogen protection, heat the mixture to 70-80℃ and keep it at this temperature for 2-3 hours to obtain an oil / water mixed emulsion. S13. After the reaction is complete, allow the mixture to cool naturally. While stirring at 400-600 rpm, slowly pour the oil / water emulsion into anhydrous ethanol at a volume of 8-10 times that of the oil / water emulsion to precipitate. Let it stand for 0.5-1.5 hours, filter to collect the solid, and wash it alternately with deionized water and anhydrous ethanol 3-5 times. Dry it under vacuum at 45-55℃ for 10-14 hours, pulverize it through a 200-mesh sieve, and obtain the water-responsive core-shell modified amine curing agent.

[0008] Preferably, the preparation method of organosilane hybrid modified corrosion-resistant filler includes the following steps: S21. By weight, take 5-8 parts of quinoline-Ce 3+ The synergistic modified layered double hydroxide was dispersed in 40-60 parts of anhydrous ethanol and ultrasonically dispersed for 10-20 min to obtain a dispersion. S22. Add dilute hydrochloric acid to adjust the pH of the dispersion to 3.5-4.5, then add 6.5-13 parts of silane mixed solution to the dispersion and react at 55-65℃ for 2-3 hours. S23. After the reaction is complete, centrifuge at 3000-5000 rpm for 5-10 min, wash with anhydrous ethanol 2-4 times, vacuum dry at 70-80℃ for 4-6 h, and pass through a 200-mesh sieve to obtain organosilane hybrid modified corrosion-resistant filler.

[0009] Preferred, quinoline-Ce 3+ The preparation method of synergistically modified layered double hydroxides includes the following steps: S211. By mass, 10-15 parts of Mg-Al-NO3 type layered double hydroxide with a Mg / Al molar ratio of 2:1-4:1 are dispersed in 100-150g of deionized water, and 1-3 parts of 8-hydroxyquinoline are added. The mixture is then subjected to hydrothermal reaction at 90-100℃ for 10-12h. S212. Centrifuge at 4000-6000 rpm for 5-10 min to collect the precipitate, wash with deionized water and anhydrous ethanol alternately 3-5 times, and dry at 60-80℃ for 4-10 h to obtain the quinoline modified layered double hydroxide precursor. S213. Disperse 7-10 parts of quinoline-modified layered double hydroxide precursor in 50-80 parts of acetic acid buffer solution with pH 5.0-6.0, add 5-8 parts of cerium nitrate solution dropwise in 2-4 equal parts, with an interval of 1-2 hours between each addition, and stir the reaction at 60-70℃ for 4-6 hours. S214. After the reaction is complete, centrifuge at 3000-5000 rpm for 5-10 min to collect the precipitate, wash with deionized water 2-4 times, and dry at 60-80℃ for 4-8 h to obtain quinoline-Ce. 3+ Synergistic modification of layered double hydroxides.

[0010] Preferably, the inorganic cementitious matrix is ​​composed of silicate cement, sulfoaluminate cement, slag powder, fly ash, kaolin and dihydrate gypsum in a mass ratio of (40-60):(10-25):(15-25):(5-15):(3-8):(2-5); Preferably, the slow-release condensation-regulating component is at least one of citric acid, tartaric acid, or boric acid; Preferably, the dispersion regulating component is a polycarboxylate superplasticizer or a naphthalene superplasticizer; Preferably, the solid epoxy resin powder is a bisphenol A type or bisphenol F type solid epoxy resin.

[0011] Preferably, the modified fatty amine curing agent is one or more of Mannich base modified fatty amine, cashew phenol modified fatty amine, or phenolic amine; Preferably, the concentration of the polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol block copolymer solution is 2-4 wt%. Preferably, the mass ratio of the functional monomer solution is acrylic acid: methyl methacrylate: N-isopropylacrylamide = (1-2): 1: (0.5-1.5). Preferably, the concentration of the potassium persulfate solution is 8-12 wt%.

[0012] Preferably, the mass ratio of the silane mixed solution is γ-aminopropyltriethoxysilane: tetraethyl orthosilicate: anhydrous ethanol = (1-2): (0.5-1): (5-10).

[0013] Preferably, the concentration of the cerium nitrate solution is 6-9 wt%.

[0014] A cementitious material for multi-aggregate curing is prepared by the above-described method.

[0015] The cementitious material for multi-aggregate curing prepared according to the above preparation method can be used in rapid road repair, base reinforcement, emergency repair or prefabricated joint grouting.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. The core of this invention relies on a moisture-responsive core-shell modified amine curing agent and an organosilane hybrid modified anti-corrosion filler. The core-shell curing agent uses a water-sensitive outer shell to achieve on-demand slow release of active amines, blocking premature cross-linking, effectively inhibiting bleeding and false coagulation, and optimizing mixing workability and interfacial adhesion. The anti-corrosion filler uses a dense Si-O-Si hybrid network to fill the matrix pores, with a core of quinoline-Ce 3+ Highly efficient Cl-locking component - SO4 2- It can resist corrosion ions and achieve chemical self-repair of microcracks through coordination, thus constructing a long-term anti-corrosion barrier and endowing microcracks with self-repair capabilities.

[0017] 2. The synergistic effect of the two forms a closed-loop mechanism of "moisture regulation-ion capture-defect repair". The slow-release rate control characteristics of the curing agent are highly matched with the dense filling effect of the filler, which greatly improves the density, impermeability and salt corrosion resistance of the cured body, and significantly extends the service life of the structure under complex working conditions. The synergistic effect of the two effectively suppresses the water-cement ratio imbalance caused by the fluctuation of the moisture content of multiple aggregates, promotes the interweaving and accumulation of hydration products, realizes the dynamic self-compactment of the matrix, and completely avoids the risk of early strength dispersion and plastic shrinkage cracking.

[0018] 3. The two-component synergistically modified cementitious material eliminates the reliance on external high-temperature curing. The cementitious material and aggregate molding mix can fully utilize their own heat of reaction to create a micro-temperature environment, achieving rapid densification at room temperature through self-heating, reaching road-ready strength in just 2 hours. This material significantly reduces curing energy consumption and fully meets the engineering needs for emergency repairs and long-term corrosion resistance under complex aggregate conditions. Attached Figure Description

[0019] Figure 1 This is a process flow diagram of the preparation process of the cementitious material for multi-aggregate curing according to the present invention; Figure 2 This is a process flow diagram for preparing the moisture-responsive core-shell modified amine curing agent of the present invention; Figure 3This is a process flow diagram for preparing the organosilane hybrid modified corrosion-resistant filler of the present invention; Figure 4 The present invention is quinoline-Ce 3+ Flowchart of the preparation process of synergistically modified layered double hydroxides; Figure 5 Scanning electron microscope (SEM) image (10 μm) of the cured cementitious material prepared for Comparative Example 1 (without the addition of the two modified components); Figure 6 Scanning electron microscope (SEM) image (20 μm) of the solidified cementitious material prepared for Comparative Example 1 (without the addition of the two modified components); Figure 7 Scanning electron microscope (SEM) image (10 μm) of the solidified cementitious material prepared in Example 1 (with two modified components added); Figure 8 Scanning electron microscope (SEM) image (20 μm) of the solidified cementitious material prepared in Example 1 (with two modified components added); Detailed Implementation The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figures 1-8 The present invention provides a technical solution: Example 1 A method for preparing a cementitious material for multi-aggregate curing: Before preparing the gelling material, a moisture-responsive core-shell modified amine curing agent and quinoline-Ce are first used. 3+ Preparation of synergistically modified layered double hydroxide and organosilane hybrid modified corrosion-resistant fillers: The preparation of a moisture-responsive core-shell modified amine curing agent includes the following steps: S11. By weight, 20g of Mannich base-modified fatty amine and 50g of polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol block copolymer solution are mixed and emulsified at 2500rpm for 10min in a 65℃ water bath to form a stable oil / water emulsion. Preparation of Mannich base-modified fatty amine: 60g cashew phenol, 21.6g m-cresol, 23.2g hexamethylenediamine, and 20.6g triethylenediamine were stirred evenly. In an 85℃ water bath, 12.6g paraformaldehyde was added to the reaction solution in 5 portions. After the paraformaldehyde was completely dissolved, the reaction solution was allowed to react at 85℃ for 3 hours. Then, vacuum distillation was performed. After the product cooled down, the Mannich base-modified fatty amine was collected.

[0021] Preparation of a 2wt% polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol block copolymer solution: In an ice-water bath, add 2g of polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol to 98.00g of deionized water, stir well, then seal and transfer to a refrigerator to stand and mature until the solution is clear and transparent and free of visible particles. S12. Slowly add 2.5g of functional monomer solution and 0.5g of potassium persulfate solution to the oil / water emulsion. Under nitrogen protection, heat the mixture to 70°C and keep it at this temperature for 2 hours to obtain an oil / water mixed emulsion. Preparation of functional monomer solution: Mix 1g acrylic acid, 1g methyl methacrylate and 0.5g N-isopropylacrylamide and stir until homogeneous; Preparation of an 8 wt% potassium persulfate solution: Add 0.8 g of potassium persulfate to 9.2 g of deionized water and stir until homogeneous; S13. After the reaction is completed, the mixture is allowed to cool naturally. While stirring at 400 rpm, the oil / water emulsion is slowly poured into anhydrous ethanol at a volume of 8 times that of the oil / water emulsion to precipitate. After standing for 0.5 h, the solid is collected by filtration and washed three times alternately with deionized water and anhydrous ethanol. The solid is then dried under vacuum at 45 °C for 10 h and pulverized through a 200-mesh sieve to obtain a water-responsive core-shell modified amine curing agent. The moisture-responsive core-shell modified amine curing agent prepared by the above method has a particle size of 15µm. The core is a modified fatty amine curing agent, and the shell is a temperature-sensitive / water-sensitive polymer layer formed by functional monomers.

[0022] Quinoline-Ce 3+ The preparation of synergistically modified layered double hydroxides includes the following steps: S211. By mass, 10g of Mg-Al-NO3 type layered double hydroxide with a Mg / Al molar ratio of 2:1 is dispersed in 100g of deionized water, and 1g of 8-hydroxyquinoline is added. The mixture is then subjected to hydrothermal reaction at 90℃ for 10h. S212. The precipitate was collected by centrifugation at 4000 rpm for 5 min, washed three times alternately with deionized water and anhydrous ethanol, and dried at 60℃ for 4 h to obtain the quinoline-modified layered double hydroxide precursor. S213. Disperse 7g of quinoline-modified layered double hydroxide precursor in 50g of acetic acid buffer solution with pH 5.0, add 5g of cerium nitrate solution dropwise in two equal portions with an interval of 1h between each addition, and stir the reaction at 60℃ for 4h. Preparation of acetic acid buffer solution with pH 5.0: Weigh 3.0451 g of glacial acetic acid and add an appropriate amount of deionized water. After cooling to room temperature, transfer to a 1000 mL volumetric flask, add deionized water to make up to volume, and shake well to prepare a 0.1 mol / L acetic acid stock solution; Dissolve 13.6088 g of sodium acetate trihydrate in 800 g of deionized water. After complete dissolution, transfer to a 1000 mL volumetric flask, make up to volume, and shake well to prepare a 0.1 mol / L sodium acetate stock solution; By adjusting the volume ratio of the acetic acid stock solution and the sodium acetate stock solution, an acetic acid buffer solution with pH 5.0 can be prepared. Preparation of a 6wt% cerium nitrate solution: Add 0.6g of cerium nitrate to 9.4mL of deionized water and stir until homogeneous; S214. After the reaction is complete, the precipitate is collected by centrifugation at 3000 rpm for 5 min, washed twice with deionized water, and dried at 60℃ for 4 h to obtain quinoline-Ce. 3+ Synergistic modification of layered double hydroxides.

[0023] Quinoline-Ce prepared by the above method 3+ The particle size of the synergistically modified layered double hydroxide is 30µm; The preparation of organosilane hybrid modified corrosion-resistant fillers includes the following steps: S21. By weight, 5g of quinoline-Ce 3+ The synergistic modified layered double hydroxide was dispersed in 40g of anhydrous ethanol and ultrasonically dispersed for 10min to obtain a dispersion. S22. Add dilute hydrochloric acid to adjust the pH of the dispersion to 3.5, then add 6.5g of silane mixed solution to the dispersion and react at 55℃ for 2h. Preparation of silane mixed solution: Add 1g of γ-aminopropyltriethoxysilane and 0.5g of tetraethyl orthosilicate to 5g of anhydrous ethanol and mix well; S23. After the reaction is complete, centrifuge at 3000 rpm for 5 min, wash twice with anhydrous ethanol, dry under vacuum at 70℃ for 4 h, and pass through a 200-mesh sieve to obtain organosilane hybrid modified anti-corrosion filler. The average thickness of the Si-O-Si hybrid network layer coated on the surface of the organosilane hybrid modified anti-corrosion filler prepared by the above method is 20 nm, and the specific surface area is 35 m² / g. The preparation method of cementitious materials includes the following steps: S1. Dry powder matrix premixing: By mass, take 75g of inorganic cementitious matrix, 0.05g of citric acid and 0.2g of polycarboxylate superplasticizer, mix them at room temperature at a speed of 150r / min for 3min, and pass them through an 80-mesh sieve to obtain the dry powder matrix; Preparation of inorganic cementitious matrix: Mix 40g silicate cement, 10g sulfoaluminate cement, 15g slag powder, 5g fly ash, 3g metakaolin and 2g dihydrate gypsum evenly. S2. Functional component compounding: Add 3g of bisphenol A type solid epoxy resin, 1.2g of moisture-responsive core-shell modified amine curing agent and 3g of organosilane hybrid modified anti-corrosion filler to the dry powder matrix, and mix at room temperature at a speed of 200r / min for 5min to obtain the gelling material.

[0024] The cementitious material obtained in Example 1 is mixed with aggregate. The method for preparing the cementitious material and aggregate mixture includes the following steps: S3. Aggregate moisture content test: Take the original manufactured sand from the construction site and test the moisture content. The moisture content is 3.8%, which is judged to be low water absorption aggregate. S4. Dynamic proportioning, mixing and molding: According to the water absorption type, 30g of cementitious material and 90g of aggregate are mixed by high-speed shearing at a mass ratio of 1:3, and then the mixture is shaped into a whole by vibration and rolling. S5. Self-heating curing: The material itself generates heat of reaction to create an internal micro-temperature environment for self-curing. After 2 hours of curing, the mixture reaches the strength required for open traffic and a solidified body is obtained.

[0025] Example 2 A method for preparing a cementitious material for multi-aggregate curing: Before preparing the gelling material, a moisture-responsive core-shell modified amine curing agent and quinoline-Ce are first used. 3+ Preparation of synergistically modified layered double hydroxide and organosilane hybrid modified corrosion-resistant fillers: The preparation of a moisture-responsive core-shell modified amine curing agent includes the following steps: S11. By weight, 40g of Mannich base-modified fatty amine and 70g of polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol block copolymer solution are mixed and emulsified at 3500rpm for 20min in a 75℃ water bath to form a stable oil / water emulsion. Preparation of Mannich base-modified fatty amine: 60g cashew phenol, 21.6g m-cresol, 23.2g hexamethylenediamine, and 20.6g triethylenediamine were stirred evenly. In an 85℃ water bath, 12.6g paraformaldehyde was added to the reaction solution in 5 portions. After the paraformaldehyde was completely dissolved, the reaction solution was allowed to react at 85℃ for 3 hours. Then, vacuum distillation was performed. After the product cooled down, the Mannich base-modified fatty amine was collected.

[0026] Preparation of a 4wt% polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol block copolymer solution: In an ice-water bath, add 4g of polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol to 96.00g of deionized water, stir well, then seal and transfer to a refrigerator to stand and mature until the solution is clear and transparent and free of visible particles. S12. Slowly add 4.5g of functional monomer solution and 1.5g of potassium persulfate solution to the oil / water emulsion. Under nitrogen protection, heat the mixture to 80℃ and keep it at that temperature for 3 hours to obtain an oil / water mixed emulsion. Preparation of functional monomer solution: Mix 2g acrylic acid, 1g methyl methacrylate and 1.5g N-isopropylacrylamide and stir until homogeneous; Preparation of a 12wt% potassium persulfate solution: Add 1.2g of potassium persulfate to 8.8g of deionized water and stir until homogeneous; S13. After the reaction is completed, the mixture is allowed to cool naturally. While stirring at 600 rpm, the oil / water emulsion is slowly poured into anhydrous ethanol at a volume of 10 times that of the oil / water emulsion to precipitate. After standing for 1.5 h, the solid is collected by filtration and washed 5 times alternately with deionized water and anhydrous ethanol. The solid is then dried under vacuum at 55 °C for 14 h and pulverized through a 200-mesh sieve to obtain a water-responsive core-shell modified amine curing agent. The moisture-responsive core-shell modified amine curing agent prepared by the above method has a particle size of 35µm. The core is a modified fatty amine curing agent, and the shell is a temperature-sensitive / water-sensitive polymer layer formed by functional monomers.

[0027] Quinoline-Ce 3+ The preparation of synergistically modified layered double hydroxides includes the following steps: S211. By mass, 15g of Mg-Al-NO3 type layered double hydroxide with a Mg / Al molar ratio of 4:1 is dispersed in 150g of deionized water, and 3g of 8-hydroxyquinoline is added. The mixture is then subjected to a hydrothermal reaction at 100℃ for 10h. S212. The precipitate was collected by centrifugation at 6000 rpm for 10 min, washed 5 times alternately with deionized water and anhydrous ethanol, and dried at 80℃ for 10 h to obtain the quinoline-modified layered double hydroxide precursor. S213. Disperse 10g of quinoline-modified layered double hydroxide precursor in 80g of acetic acid buffer solution with pH 6.0, add 8g of cerium nitrate solution dropwise in 4 equal portions, with an interval of 2h between each addition, and stir the reaction at 70℃ for 6h. Preparation of acetic acid buffer solution with pH 6.0: Weigh 3.0451 g of glacial acetic acid and add an appropriate amount of deionized water. After cooling to room temperature, transfer to a 1000 mL volumetric flask, add deionized water to make up to volume, and shake well to prepare a 0.1 mol / L acetic acid stock solution; Dissolve 13.6088 g of sodium acetate trihydrate in 800 g of deionized water. After complete dissolution, transfer to a 1000 mL volumetric flask, make up to volume, and shake well to prepare a 0.1 mol / L sodium acetate stock solution; By adjusting the volume ratio of the acetic acid stock solution and the sodium acetate stock solution, an acetic acid buffer solution with pH 6.0 can be prepared. Preparation of a 9wt% cerium nitrate solution: Add 0.9g of cerium nitrate to 9.1mL of deionized water and stir until homogeneous; S214. After the reaction is complete, the precipitate is collected by centrifugation at 5000 rpm for 10 min, washed four times with deionized water, and dried at 80℃ for 8 h to obtain quinoline-Ce. 3+ Synergistic modification of layered double hydroxides.

[0028] Quinoline-Ce prepared by the above method 3+ The particle size of the synergistically modified layered double hydroxide is 45µm; The preparation of organosilane hybrid modified corrosion-resistant fillers includes the following steps: S21. By weight, 8g of quinoline-Ce 3+ The synergistically modified layered double hydroxide was dispersed in 60g of anhydrous ethanol and ultrasonically dispersed for 20min to obtain a dispersion. S22. Add dilute hydrochloric acid to adjust the pH of the dispersion to 4.5, then add 13g of silane mixed solution to the dispersion and react at 65℃ for 3h. Preparation of silane mixed solution: Add 2g of γ-aminopropyltriethoxysilane and 1g of tetraethyl orthosilicate to 10g of anhydrous ethanol and mix well; S23. After the reaction is complete, centrifuge at 5000 rpm for 10 min, wash 4 times with anhydrous ethanol, vacuum dry at 80℃ for 6 h, and pass through a 200-mesh sieve to obtain organosilane hybrid modified anti-corrosion filler. The average thickness of the Si-O-Si hybrid network layer coated on the surface of the organosilane hybrid modified anti-corrosion filler prepared by the above method is 40 nm, and the specific surface area is 65 m² / g. The preparation method of cementitious materials includes the following steps: S1. Dry powder matrix premixing: By mass, take 138g of inorganic cementitious matrix, 1g of citric acid and 2g of polycarboxylate superplasticizer, mix them at room temperature at a speed of 200r / min for 5min, and pass them through an 80-mesh sieve to obtain the dry powder matrix. Preparation of inorganic cementitious matrix: Mix 60g silicate cement, 25g sulfoaluminate cement, 25g slag powder, 15g fly ash, 8g metakaolin and 5g dihydrate gypsum evenly. S2. Functional component compounding: Add 8g of bisphenol A type solid epoxy resin, 3.2g of moisture-responsive core-shell modified amine curing agent and 8g of organosilane hybrid modified anti-corrosion filler to the dry powder matrix, mix at room temperature at a speed of 300r / min for 10min to obtain the gelling material. The cementitious material obtained in Example 1 is mixed with aggregate. The method for preparing the cementitious material and aggregate mixture includes the following steps: S3. Aggregate moisture content test: Take the original coral sand and recycled concrete mixed aggregate from the construction site. The moisture content is 6.5%, which is judged to be high water absorption aggregate. S4. Dynamic proportioning, mixing and molding: According to the water absorption type, 30g of cementitious material and 150g of aggregate are mixed at a mass ratio of 1:5 by high-speed shearing, and then the mixture is shaped into a whole by vibration and rolling. S5. Self-heating curing: The material itself generates heat of reaction to create an internal micro-temperature environment for self-curing. After 2 hours of curing, the mixture reaches the strength required for open traffic and a solidified body is obtained.

[0029] Example 3 A method for preparing a cementitious material for multi-aggregate curing: Before preparing the gelling material, a moisture-responsive core-shell modified amine curing agent and quinoline-Ce are first used. 3+ Preparation of synergistically modified layered double hydroxide and organosilane hybrid modified corrosion-resistant fillers: The preparation of a moisture-responsive core-shell modified amine curing agent includes the following steps: S11. By weight, 30g of Mannich base-modified fatty amine and 60g of polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol block copolymer solution are mixed and emulsified at 3000rpm for 15min in a 70℃ water bath to form a stable oil / water emulsion. Preparation of Mannich base-modified fatty amine: 60g cashew phenol, 21.6g m-cresol, 23.2g hexamethylenediamine, and 20.6g triethylenediamine were stirred evenly. In an 85℃ water bath, 12.6g paraformaldehyde was added to the reaction solution in 5 portions. After the paraformaldehyde was completely dissolved, the reaction solution was allowed to react at 85℃ for 3 hours. Then, vacuum distillation was performed. After the product cooled down, the Mannich base-modified fatty amine was collected.

[0030] Preparation of a 3wt% polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol block copolymer solution: In an ice-water bath, add 3g of polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol to 97.00g of deionized water, stir well, then seal and transfer to a refrigerator to stand and mature until the solution is clear and transparent and free of visible particles. S12. Slowly add 3.5g of functional monomer solution and 1g of potassium persulfate solution to the oil / water emulsion. Under nitrogen protection, the temperature is raised to 75℃ and kept at this temperature for 2.5h to obtain an oil / water mixed emulsion. Preparation of functional monomer solution: Mix 1.5g acrylic acid, 1g methyl methacrylate and 1g N-isopropylacrylamide and stir until homogeneous; Preparation of a 10wt% potassium persulfate solution: Add 1g of potassium persulfate to 9g of deionized water and stir until homogeneous; S13. After the reaction is completed, the mixture is allowed to cool naturally. Under stirring at 500 rpm, the oil / water emulsion is slowly poured into anhydrous ethanol at a volume of 9 times that of the oil / water emulsion to precipitate. After standing for 1 hour, the solid is collected by filtration and washed 4 times alternately with deionized water and anhydrous ethanol. The solid is then dried under vacuum at 50°C for 13 hours and pulverized through a 200-mesh sieve to obtain a water-responsive core-shell modified amine curing agent. The moisture-responsive core-shell modified amine curing agent prepared by the above method has a particle size of 25µm. The core is a modified fatty amine curing agent, and the shell is a temperature-sensitive / water-sensitive polymer layer formed by functional monomers.

[0031] Quinoline-Ce 3+ The preparation of synergistically modified layered double hydroxides includes the following steps: S211. By mass, 12.5g of Mg-Al-NO3 type layered double hydroxide with a Mg / Al molar ratio of 3:1 is dispersed in 120g of deionized water, and 2g of 8-hydroxyquinoline is added. The mixture is then subjected to hydrothermal reaction at 95℃ for 11h. S212. The precipitate was collected by centrifugation at 5000 rpm for 7 min, washed 4 times alternately with deionized water and anhydrous ethanol, and dried at 70℃ for 7 h to obtain the quinoline-modified layered double hydroxide precursor. S213. Disperse 8.5g of quinoline-modified layered double hydroxide precursor in 65g of acetic acid buffer solution with pH 5.5, add 6.5g of cerium nitrate solution dropwise in 3 equal portions, with an interval of 1.5h between each addition, and stir the reaction at 65℃ for 5h. Preparation of an acetate buffer solution with pH 5.5: Weigh 3.0451 g of glacial acetic acid and add an appropriate amount of deionized water. After cooling to room temperature, transfer to a 1000 mL volumetric flask, add deionized water to make up to volume, and shake well to prepare a 0.1 mol / L acetic acid stock solution. Dissolve 13.6088 g of sodium acetate trihydrate in 800 g of deionized water. After complete dissolution, transfer to a 1000 mL volumetric flask, make up to volume, and shake well to prepare a 0.1 mol / L sodium acetate stock solution. By adjusting the volume ratio of the acetic acid stock solution and the sodium acetate stock solution, an acetate buffer solution with pH 5.5 can be prepared. Preparation of a 7wt% cerium nitrate solution: Add 0.7g of cerium nitrate to 9.3mL of deionized water and stir until homogeneous; S214. After the reaction is complete, the precipitate is collected by centrifugation at 4000 rpm for 7 min, washed three times with deionized water, and dried at 70℃ for 6 h to obtain quinoline-Ce. 3+ Synergistic modification of layered double hydroxides.

[0032] Quinoline-Ce prepared by the above method 3+ The particle size of the synergistically modified layered double hydroxide is 35µm; The preparation of organosilane hybrid modified corrosion-resistant fillers includes the following steps: S21. By weight, 6.5g of quinoline-Ce 3+ The synergistic modified layered double hydroxide was dispersed in 50g of anhydrous ethanol and ultrasonically dispersed for 15min to obtain a dispersion. S22. Add dilute hydrochloric acid to adjust the pH of the dispersion to 4, then add 9.7g of silane mixed solution to the dispersion and react at 60℃ for 2.5h. Preparation of silane mixed solution: Add 1.5g of γ-aminopropyltriethoxysilane and 0.7g of tetraethyl orthosilicate to 7.5g of anhydrous ethanol and mix well; S23. After the reaction is complete, centrifuge at 4000 rpm for 7 min, wash three times with anhydrous ethanol, vacuum dry at 75℃ for 5 h, and pass through a 200-mesh sieve to obtain organosilane hybrid modified anti-corrosion filler. The average thickness of the Si-O-Si hybrid network layer coated on the surface of the organosilane hybrid modified anti-corrosion filler prepared by the above method is 30 nm, and the specific surface area is 50 m² / g. The preparation method of cementitious materials includes the following steps: S1. Dry powder matrix premixing: By mass, take 75g of inorganic cementitious matrix, 0.05g of citric acid and 0.2g of polycarboxylate superplasticizer, mix them at room temperature at a speed of 150r / min for 3min, and pass them through an 80-mesh sieve to obtain the dry powder matrix; Preparation of inorganic cementitious matrix: Mix 40g silicate cement, 10g sulfoaluminate cement, 15g slag powder, 5g fly ash, 3g metakaolin and 2g dihydrate gypsum evenly. S2. Functional component compounding: Add 3g of bisphenol A type solid epoxy resin, 1.2g of moisture-responsive core-shell modified amine curing agent and 3g of organosilane hybrid modified anti-corrosion filler to the dry powder matrix, and mix at 200r / min for 5min at room temperature to obtain the gelling material. The cementitious material obtained in Example 1 is mixed with aggregate. The method for preparing the cementitious material and aggregate mixture includes the following steps: S3. Aggregate moisture content test: Take a mixed aggregate of sea sand and river sand and test the surface moisture content. If it is 5%, it is determined to be a highly absorbent aggregate. S4. Dynamic proportioning, mixing and molding: According to the water absorption type, 30g of cementitious material and 120g of aggregate are mixed by high-speed shearing at a mass ratio of 1:4, and then the mixture is shaped into a whole by vibration and rolling. S5. Self-heating curing: The material itself generates heat of reaction to create an internal micro-temperature environment for self-curing. After 2 hours of curing, the mixture reaches the strength required for open traffic and a solidified body is obtained.

[0033] Comparative Example 1 The only difference between Comparative Example 1 and Example 1 is that no moisture-responsive core-shell modified amine curing agent and organosilane hybrid modified anti-corrosion filler were added in this comparative example. The remaining steps are exactly the same in Comparative Example 1 and Example 1.

[0034] Comparative Example 2 The only difference between Comparative Example 2 and Example 1 is that no organosilane hybrid modified anti-corrosion filler was added in this comparative example; the other steps are exactly the same in Comparative Example 2 and Example 1.

[0035] Comparative Example 3 The only difference between Comparative Example 3 and Example 1 is that no moisture-responsive core-shell modified amine curing agent was added in this comparative example; the other steps are exactly the same in Comparative Example 3 and Example 1.

[0036] Performance metrics testing: Standardized performance tests were conducted on the cured bodies prepared in Examples 1-3 and Comparative Examples 1-3, based on the following criteria: Setting time during the preparation of the cured body: determined according to GB / T1346-2011 Standard Method for Testing the Consistency Water Requirement, Setting Time and Soundness of Cement; Compressive strength: determined according to GB / T17671-2021 Test Method for Strength of Cement Mortar at 2 hours and 28 days; Chloride ion diffusion coefficient: determined according to the RCM method in GB / T50082-2009 Standard for Test Methods of Long-Term Performance and Durability of Ordinary Concrete; Sulfate erosion strength retention rate: after placing the specimen in a 5% Na2SO4 solution for 30 wet-dry cycles, the compressive strength was tested and the retention rate was calculated.

[0037] Table 1: Summary of Performance Index Test Results Analysis of table results: Compared with Comparative Example 1, the two-component synergistic system extended the initial setting time from 38 min to 48 min, avoiding the risk of false setting, while achieving a comprehensive improvement in mechanical and durability properties: the 2-hour and 28-day compressive strengths increased from 18.3 MPa and 45.2 MPa to 32.5 MPa and 68.4 MPa, respectively, and the chloride ion diffusion coefficient increased from 8.5 × 10⁻⁶ MPa to 48.4 MPa. -12 m² / s decreased to 3.2 × 10 -12 The strength retention rate after sulfate attack increased from 72.3% to 92.5% with a m² / s, indicating that the synergistic effect of the moisture-responsive core-shell modified amine curing agent and organosilane hybrid filler can optimize the hydration structure and achieve a comprehensive balance of setting regulation, strengthening and corrosion resistance.

[0038] Further comparison of Example 1 with the single-component system reveals the following: Compared to Comparative Example 2, which contains only organosilane hybrid filler, Example 1 exhibits a 17.3% increase in strength and a 42.9% decrease in diffusion coefficient, while maintaining a similar setting time. Compared to Comparative Example 3, which contains only curing agent, Example 1 achieves a 9.1% increase in strength and a further 34.7% decrease in diffusion coefficient while moderately extending the initial setting time. This comparison demonstrates that the two components are complementary in their slow-release setting regulation and densification barrier properties, and their synergistic use can balance application applicability, early strength development, and long-term corrosion resistance stability.

[0039] Characterization results analysis: At low magnification (20 μm, Figure 6 vs Figure 8 In contrast, the solidified body of Comparative Example 1 shows a large number of interconnected pores and obvious microcracks in the aggregate-slurry interface transition zone; while the solidified body of Example 1 has a more compact structure, a significantly reduced number of large-sized pores, narrowed gaps in the interface transition zone, and a tight bond between the aggregate and the slurry.

[0040] In high magnification (10μm, Figure 5 vs Figure 7 In Comparative Example 1, the hydration products exhibited a loosely aggregated state, with needle-like hydration product crystals growing randomly and failing to form a continuous cemented network. In contrast, the hydration products of Example 1 showed interwoven growth, significantly increased packing density, and no obvious microcracks were observed within the solidified body. Furthermore, Figure 7 The visible nanoscale sheet-like material is uniformly dispersed in the solidified body, which plays a role in filling pores and refining the microstructure.

[0041] In summary, moisture-responsive core-shell modified amine curing agents and organosilane hybrid modified anti-corrosion fillers possess their own independent functional advantages in cementitious material systems. They can also achieve synergistic effects to superimpose and complement each other's performance, thereby significantly improving the early strength development capability, long-term mechanical stability, and durability of multi-aggregate curing systems under complex corrosive environments.

[0042] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a cementitious material for multi-aggregate curing, characterized in that, Includes the following steps: S1. Dry powder matrix premixing: By mass, take 75-138 parts of inorganic cementitious matrix, 0.05-1 parts of slow-release setting agent and 0.2-2 parts of dispersion regulating agent, mix at room temperature at a speed of 150-200 r / min for 3-5 min, and pass through an 80 mesh sieve to obtain dry powder matrix; S2, Functional component compounding: Add 3-8 parts of solid epoxy resin powder, 1.2-3.2 parts of moisture-responsive core-shell modified amine curing agent and 3-8 parts of organosilane hybrid modified anti-corrosion filler to the dry powder matrix obtained in step S1, and mix at room temperature at a speed of 200-300 r / min for 5-10 min to obtain the gelling material. The preparation method of the moisture-responsive core-shell modified amine curing agent includes the following steps: S11. By weight, mix 20-40 parts of modified fatty amine curing agent with 50-70 parts of polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol block copolymer solution, and emulsify at high speed of 2500-3500 rpm for 10-20 minutes in a water bath at 65-75℃ to form a stable oil / water emulsion. S12. Slowly add 2.5-4.5 parts of functional monomer solution and 0.5-1.5 parts of potassium persulfate solution to the oil / water emulsion. Under nitrogen protection, heat the mixture to 70-80℃ and keep it at this temperature for 2-3 hours to obtain an oil / water mixed emulsion. S13. After the reaction is complete, allow the mixture to cool naturally. While stirring at 400-600 rpm, slowly pour the oil / water emulsion into anhydrous ethanol at a volume of 8-10 times that of the oil / water emulsion to precipitate. Let it stand for 0.5-1.5 hours, filter to collect the solid, and wash it alternately with deionized water and anhydrous ethanol 3-5 times. Dry it under vacuum at 45-55℃ for 10-14 hours, pulverize it through a 200-mesh sieve, and obtain the water-responsive core-shell modified amine curing agent.

2. The method for preparing a cementitious material for multi-aggregate curing according to claim 1, characterized in that, The preparation method of the organosilane hybrid modified corrosion-resistant filler includes the following steps: S21. By weight, take 5-8 parts of quinoline-Ce 3+ The synergistic modified layered double hydroxide was dispersed in 40-60 parts of anhydrous ethanol and ultrasonically dispersed for 10-20 min to obtain a dispersion. S22. Add dilute hydrochloric acid to adjust the pH of the dispersion to 3.5-4.5, then add 6.5-13 parts of silane mixed solution to the dispersion and react at 55-65℃ for 2-3 hours. S23. After the reaction is complete, centrifuge at 3000-5000 rpm for 5-10 min, wash with anhydrous ethanol 2-4 times, vacuum dry at 70-80℃ for 4-6 h, and pass through a 200-mesh sieve to obtain organosilane hybrid modified corrosion-resistant filler.

3. The method for preparing a cementitious material for multi-aggregate curing according to claim 2, characterized in that, The quinoline-Ce 3+ The preparation method of synergistically modified layered double hydroxides includes the following steps: S211. By mass, 10-15 parts of Mg-Al-NO3 type layered double hydroxide with a Mg / Al molar ratio of 2:1-4:1 are dispersed in 100-150g of deionized water, and 1-3 parts of 8-hydroxyquinoline are added. The mixture is then subjected to hydrothermal reaction at 90-100℃ for 10-12h. S212. Centrifuge at 4000-6000 rpm for 5-10 min to collect the precipitate, wash with deionized water and anhydrous ethanol alternately 3-5 times, and dry at 60-80℃ for 4-10 h to obtain the quinoline modified layered double hydroxide precursor. S213. Disperse 7-10 parts of quinoline-modified layered double hydroxide precursor in 50-80 parts of acetic acid buffer solution with pH 5.0-6.0, add 5-8 parts of cerium nitrate solution dropwise in 2-4 equal parts, with an interval of 1-2 hours between each addition, and stir the reaction at 60-70℃ for 4-6 hours. S214. After the reaction is complete, centrifuge at 3000-5000 rpm for 5-10 min to collect the precipitate, wash with deionized water 2-4 times, and dry at 60-80℃ for 4-8 h to obtain quinoline-Ce. 3+ Synergistic modification of layered double hydroxides.

4. The method for preparing a cementitious material for multi-aggregate curing according to claim 1, characterized in that, The inorganic cementitious matrix is ​​composed of silicate cement, sulfoaluminate cement, slag powder, fly ash, metakaolin and dihydrate gypsum in a mass ratio of (40-60):(10-25):(15-25):(5-15):(3-8):(2-5); The slow-release condensing component is at least one of citric acid, tartaric acid, or boric acid. The dispersion regulating component is a polycarboxylate-based water-reducing agent or a naphthalene-based water-reducing agent; The solid epoxy resin powder is a bisphenol A or bisphenol F type solid epoxy resin.

5. A method for preparing a cementitious material for multi-aggregate curing according to claim 1, characterized in that, The modified fatty amine curing agent is one or more of Mannich base modified fatty amine, cashew phenol modified fatty amine, or phenolic amine. The concentration of the polyethylene glycol-b-polypropylene glycol-b-polyethylene glycol block copolymer solution is 2-4 wt%.

6. The method for preparing a cementitious material for multi-aggregate curing according to claim 1, characterized in that, The mass ratio of the functional monomer solution is acrylic acid: methyl methacrylate: N-isopropylacrylamide = (1-2): 1: (0.5-1.5). The concentration of the potassium persulfate solution is 8-12 wt%.

7. A method for preparing a cementitious material for multi-aggregate curing according to claim 2, characterized in that, The mass ratio of the silane mixed solution is γ-aminopropyltriethoxysilane: tetraethyl orthosilicate: anhydrous ethanol = (1-2): (0.5-1): (5-10).

8. A method for preparing a cementitious material for multi-aggregate curing according to claim 3, characterized in that, The concentration of the cerium nitrate solution is 6-9 wt%.

9. A cementitious material for multi-aggregate curing, characterized in that, The cementitious material is prepared by the preparation method described in any one of claims 1-8.

10. The application of the cementitious material for multi-aggregate curing as described in claim 9 in rapid road repair, base reinforcement, emergency repair, or prefabricated joint grouting.

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