Concrete anti-erosion preservative based on nano-modified regenerated micro powder, preparation method and application

Abstract

The invention discloses a concrete anti-erosion preservative based on nano-modified regenerated micro-powder, a preparation method and application. The concrete anti-erosion preservative comprises 30-50 parts of nano-modified regenerated micro-powder; 40 to 50 parts of an expansion component; 5-10 parts of an anti-corrosion component; 0.5-2 parts of a water reducing component; and 3-12 parts of a barium ion-based polyethylene glycol ion curing agent. The preparation method comprises the following steps: preparing nano modified regenerated micro powder; weighing the mass of each raw material according to the mixing ratio; after the raw materials are uniformly stirred, the nano-modified regenerated micro-powder concrete anti-erosion preservative is obtained. The method can be applied to sea-crossing bridges, deep sea platforms or wharf structures. According to the present invention, the triple protection mechanism of physical permeation resistance, biological inhibition and chemical strengthening is adopted, and is used as the additive to be doped into the concrete, such that the Cl <-> diffusion coefficient can be reduced by more than 50%, the corrosion resistance coefficient can achieve 1.32, the 28d compressive strength ratio can be increased to 108.8%, and the concrete has advantages of controllable expansion coefficient (less than or equal to 1.12), environmental protection and the like, and is suitable for the harsh marine environments such as sea-crossing bridges, deep sea platforms and the like.

Description

Technical Field

[0001] This application belongs to the field of chemical additives for building materials, specifically relating to an anti-erosion and corrosion-resistant agent for nano-modified recycled micro powder concrete, its preparation method, and its application. Background Technology

[0002] In marine environments, concrete structures are exposed to chloride ions (Cl-) and sulfate ions (SO4-) for extended periods. 2- Under the combined effects of multiple corrosive factors, including microbial erosion and wet-dry cycles, concrete is prone to corrosion, cracking, and spalling, leading to durability deterioration and severely impacting the service life and safety of engineering structures. Statistics show that direct economic losses due to concrete corrosion in marine engineering projects exceed US$100 billion annually worldwide, making the improvement of corrosion prevention technology a critical technical issue urgently needing resolution. Currently, traditional anti-corrosion and anti-corrosion measures mainly include silane impregnation, epoxy coating, and modification with mineral admixtures (such as fly ash and slag). While these methods can improve the durability of concrete to some extent, they still have the following significant limitations:

[0003] (1) Performance defects of traditional anti-corrosion technologies: (a) Single protection mechanisms are difficult to meet the needs of complex corrosion environments. Silane-based hydrophobic materials mainly rely on hydrophobic and seepage-blocking effects, which cannot effectively prevent chemical and biological factors such as sulfate corrosion and biological corrosion; epoxy coatings are prone to peeling and failure during service due to interface stress concentration or microcrack propagation, and the maintenance and repair costs are high; (b) Poor compatibility of expansion anti-crack materials. Traditional expansion components (such as sulfoaluminate expansion agents) have a fast early hydration rate and concentrated expansion peaks, but are prone to shrinkage and rebound in the later stages, making it difficult to form a synergistic effect with mineral admixtures, and may even induce microcracks; (c) Ion curing technology is immature: Traditional rust inhibitors (such as nitrites) fix Cl- through physical adsorption, but are prone to desorption due to changes in environmental pH, and there is a risk of toxic pollution.

[0004] (2) Shortcomings in the synergy of existing material systems: (a) Insufficient activity of filler components. Conventional mineral admixtures such as fly ash and slag typically have a specific surface area of ​​less than 400 m² / kg and an activity index of less than 80% after 28 days, which is not conducive to improving the density and ion blocking ability of concrete; (b) Limited corrosion resistance: For example, the invention disclosed in CN115259738A discloses a composite anti-corrosion material system based on calcium salt-fly ash-polycarboxylic acid, which can reduce the chloride ion diffusion coefficient to a certain extent, but lacks inhibitory effect on biological corrosion caused by sulfate-reducing bacteria, and has limited functional coverage; (c) Contradiction between environmental protection and economy: At present, high-performance anti-corrosion materials mostly rely on high-energy-consuming processes such as high-temperature calcination and chemical purification for preparation, and the raw materials are mostly sourced from outside. The utilization rate of industrial solid waste resources is low, which is not conducive to building a low-carbon and environmentally friendly green building material system and restricts its promotion and application in large-scale marine engineering.

[0005] As can be seen from the above, the existing anti-corrosion technology for marine concrete still has significant shortcomings in terms of material stability, integrity of protection mechanism, resource utilization efficiency and environmental economy. Therefore, there is an urgent need in this field to develop a new composite anti-corrosion material system with multiple anti-corrosion mechanisms, high synergy and sustainable resource utilization capabilities to meet the durability requirements of long-term service in marine engineering and the development needs of green building materials. Summary of the Invention

[0006] In view of the shortcomings or deficiencies of the existing technologies, the technical problem to be solved by this application is a multi-dimensional synergistic effect based on nano-modified recycled micro powder concrete anti-corrosion agent, preparation method and application. Through the triple innovation of "component optimization - functional coupling - green preparation", it breaks through the traditional technical bottleneck and aims to provide a long-lasting and environmentally friendly concrete protection solution for harsh environments such as cross-sea bridges and deep-sea platforms.

[0007] To solve the above-mentioned technical problems, this application provides the following technical solution:

[0008] This application proposes a nano-modified recycled micro-powder concrete anti-erosion and corrosion-preserving agent, characterized in that it comprises the following components by weight:

[0009] 30-50 parts of nano-modified recycled micro powder;

[0010] 40-50 parts of the expanding component;

[0011] 5-10 parts of anti-corrosion component;

[0012] Water-reducing component: 0.5-2 parts;

[0013] 3-12 parts of barium ion-based polyethylene glycol ion curing agent.

[0014] Further, optionally, 40-50 parts of the above-mentioned nano-modified regenerated micro powder;

[0015] 45-50 parts of the expanding component;

[0016] 6-10 parts of preservative component;

[0017] Water-reducing agent 0.5-1 part;

[0018] 6-12 parts of ion-based polyethylene glycol ion curing agent.

[0019] Further optionally, the nano-modified recycled powder is recycled powder with nano-silica grafted onto its surface in situ; and / or, the nano-modified recycled powder is recycled concrete powder with a particle size of less than 75 μm after crushing.

[0020] Further optionally, the expansion component is composed of a sulfoaluminate type expansion agent and zeolite powder in a mass ratio of (60-90):(10-40);

[0021] The sulfoaluminate type expanding agent is in powder form with a specific surface area > 300 m². 2 / kg, MgO content ≤5.0%, total alkali content ≤0.75%;

[0022] The zeolite powder has a particle size of <60μm and a natural zeolite content of >65%.

[0023] Further optionally, the anti-corrosion component is composed of calcium stearate, sodium benzoate and acrylate in a mass ratio of (30-50):(10-30):(20-40).

[0024] More preferably, the preservative component is a mixture of one or more of the following in any proportion: powdered stearate, sodium benzoate, and acrylate.

[0025] This application combines calcium stearate, sodium benzoate, and acrylate to construct a multi-dimensional synergistic protection system. Calcium stearate, with its hydrophobic long chains, reacts with the Ca produced during cement hydration. 2+ Combined, they are arranged in an orderly manner on the surface of concrete pores, forming a dense hydrophobic layer that effectively blocks moisture, Cl-, and SO4. 2- The capillary permeation pathway is utilized; sodium benzoate, through the electrostatic adsorption properties of its benzene ring structure and sodium ions, precisely targets the cell membranes of microorganisms, inhibiting the activity of acid-producing microorganisms such as sulfate-reducing bacteria, thus curbing the erosion of biological acids at the source; the carboxyl groups of acrylate coordinate with calcium stearate metal ions, self-polymerizing into a flexible polymer network in an alkaline environment, which not only fills microcracks but also tightly cross-links with the hydrophobic layer. These three components work synergistically through a triple mechanism of "physical impermeability—biological inhibition—chemical reinforcement," ultimately forming a "rigid hydrophobic—flexible dense" interpenetrating protective membrane, comprehensively enhancing the erosion resistance of concrete.

[0026] Further optionally, the water-reducing component is one of the following: powdered polycarboxylic acid, naphthalene sulfonic acid, or aminosulfonic acid water-reducing agents. By adding water-reducing agent powder, the dispersibility of cementitious materials is improved, thereby improving the workability of concrete.

[0027] Further optionally, the barium ion-based polyethylene glycol ion curing agent is formed by linking barium ions to polyethylene glycol molecules, wherein the barium ion loading is >1.0 mmol / g, the polyethylene glycol molecular weight is 800-10000 Da, and the barium ions are derived from one or a mixture of two or more of barium nitrate, barium chloride, or barium slag powder.

[0028] Further optionally, nano-silica is grafted in situ onto the surface of the nano-modified recycled powder, and the nano-modified recycled powder concrete anti-corrosion agent is prepared by hydrolysis and condensation reaction of the recycled powder, tetraethyl orthosilicate, deionized water, anhydrous ethanol, and ammonia.

[0029] This application also proposes a method for preparing the aforementioned anti-erosion and corrosion-resistant agent for nano-modified recycled micro-powder concrete, comprising:

[0030] Preparation of nano-modified regenerated micro powders;

[0031] Weigh the mass of each raw material according to the mixing ratio of nano-modified recycled powder, expansion component, anti-corrosion component, water-reducing component and barium ion-based polyethylene glycol ion curing agent; specifically, pass each of the above raw materials through a 200-300 mesh sieve.

[0032] After mixing the above raw materials evenly, a nano-modified recycled micro powder concrete anti-erosion and anti-corrosion agent is obtained.

[0033] Optionally, the preparation of the above-mentioned nano-modified regenerated micropowder includes: using tetraethyl orthosilicate, anhydrous ethanol, polyethylene glycol, deionized water, and ammonia as raw materials, and achieving in-situ grafting of nano-silica onto the surface of the regenerated micropowder through a hydrolysis-condensation reaction; in the hydrolysis-condensation reaction, anhydrous ethanol is used as a co-solvent, ammonia as a catalyst, and polyethylene glycol as a surfactant. The in-situ grafting of nano-silica onto the surface of the regenerated micropowder is obtained through the following method:

[0034] The powder from crushed concrete is passed through a 200-mesh sieve. The sieved powder is then immersed in a dilute HCl solution. After immersion, it is washed with water and dried to obtain recycled micro powder.

[0035] Solution A is obtained by mixing tetraethyl orthosilicate and a portion of anhydrous ethanol; Deionized water, anhydrous ethanol and regenerated micro powder are mixed in a beaker and stirred evenly to obtain a regenerated micro powder mixture.

[0036] A certain amount of ammonia, polyethylene glycol and anhydrous ethanol are mixed and stirred to obtain mixed solution B; then, mixed solution B is stirred evenly with the regenerated micro powder mixture to obtain mixture B1;

[0037] Place mixture B1 in a water bath and solution A in a separatory funnel; add solution A dropwise to mixture B1. Stir mixture B1 continuously during the addition process. After the water bath reaction is complete, allow the mixed solution in the beaker to stand and age.

[0038] After aging, the powder is washed with anhydrous ethanol or deionized water and dried to obtain a powder with in-situ grafted nano-silica on the surface of the regenerated micro powder.

[0039] Further optionally, the pH value of the dilute hydrochloric acid is 2-4; the number of water washes is 3-6 times; and the drying temperature is 40-60℃.

[0040] More preferably, the concentration of the tetraethyl orthosilicate is 0.1–0.6 mol / L, the molar ratio of tetraethyl orthosilicate to deionized water is 1:4, and the solid-liquid ratio of the regenerated micro powder to the total mass of the solution is 1:10.

[0041] More preferably, the polyethylene glycol has a molecular weight of 800-8000 Da and a concentration of 30-50 mg / L, and the ammonia solution has a concentration of 0.5-0.8 mol / L;

[0042] More preferably, the water bath reaction temperature is 40-80℃, the water bath time is 6-12h; the dropping time is 1-4h, the aging time is 12-36h, the washing is performed 3-5 times, and the drying is performed in a drying oven at 60℃.

[0043] The anti-corrosion component is added to the concrete as an admixture to replace part of the cement, and its dosage is 6 to 12% of the cement mass.

[0044] More preferably, the various raw materials, including nano-modified recycled micro powder, expansion component, anti-corrosion component, water-reducing agent, and barium ion-based polyethylene glycol ion curing agent, are placed in a dry mixing machine and mixed evenly to obtain a concrete anti-erosion and anti-corrosion agent based on nano-modified recycled micro powder.

[0045] This application also proposes the application of the above-mentioned anti-corrosion and corrosion-resistant agent based on nano-modified recycled micro powder concrete, characterized in that it is applied to cross-sea bridges, deep-sea platforms or dock structures.

[0046] Compared with the prior art, this application has the following technical effects:

[0047] Compared with traditional concrete anti-corrosion and corrosion inhibitors, the nano-modified recycled micro-powder concrete anti-corrosion and corrosion inhibitor proposed in this application has significant advantages in terms of technical mechanism, environmental benefits, and comprehensive performance. This application breaks through traditional technical bottlenecks through a triple innovation of "component optimization—functional coupling—green preparation."

[0048] (1) Innovative Multidimensional Synergistic Anticorrosion Mechanism: Traditional anticorrosive agents mostly rely on single physical barrier or chemical passivation mechanisms (such as silane impregnation or nitrite rust inhibition), while the anticorrosive component of this application constructs a triple synergistic protection mechanism of "hydrophobic barrier - biological inhibition - self-repair network" through a ternary compound system of calcium stearate-sodium benzoate-acrylate. The long-chain alkyl group of calcium stearate in Ca... 2+Under the guidance of the molecule, an ordered molecular membrane is formed, which interacts with the flexible acrylate network to form a rigid-flexible interpenetrating structure, reducing the chloride ion permeability coefficient. The sodium benzoate benzene ring conjugated system adsorbs onto the cell membrane of sulfate-reducing bacteria, disrupting the electron transport chain, inhibiting bio-erosion, and improving the overall corrosion resistance of the material.

[0049] (2) Interface strengthening effect of nano-modification of recycled micropowder: By in-situ grafting of nano-SiO2 onto the surface of recycled micropowder through the hydrolysis and condensation of tetraethyl orthosilicate, a dual breakthrough of "waste resource utilization" and "nano-reinforcement" is achieved. The pozzolanic activity of nano-SiO2 and the micro-aggregate effect of recycled micropowder work synergistically to reduce the porosity of the cement matrix. Replacing 30%-60% of traditional mineral admixtures with recycled micropowder can reduce carbon emissions by 120-150 kg per cubic meter of concrete. The nano-modification process avoids the agglomeration and loss of nanoparticles through in-situ grafting, which can significantly reduce energy consumption compared with the traditional external admixture of nanomaterials.

[0050] (3) Optimization of dynamic ionic crosslinking and volume stability: A barium ion-based polyethylene glycol ionic curing agent was introduced, whose Ba... 2+ It interacts with the silicon-oxygen tetrahedra in CSH gel to form a three-dimensional ionic cross-linked network through charge balancing. At the same time, the gradation design of sulfoaluminate expander and zeolite powder achieves time-space matching of expansion efficiency, effectively compensating for shrinkage and sealing capillary channels.

[0051] The core advantage of this application lies in its integrated design of materials, structure, and function, which breaks through the technical bottlenecks of the single-effect nature and high environmental load of traditional anti-corrosion systems, and provides an innovative solution for improving the durability of concrete structures in harsh environments such as marine engineering and saline soil areas. Attached Figure Description

[0052] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0053] Figure 1 SEM image of regenerated micro powder in one embodiment of this application;

[0054] Figure 2 SEM image (magnification 200x) of nano-modified regenerated micropowder in one embodiment of this application;

[0055] Figure 3 SEM image (magnification 20,000x) of nano-silica on the surface of nano-modified regenerated micropowder in one embodiment of this application. Detailed Implementation

[0056] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0057] This embodiment is implemented based on the technical solution of this application, and provides detailed implementation methods and specific operation processes, but the protection scope of this application is not limited to the following embodiment.

[0058] The nano-modified recycled micro-powder concrete anti-corrosion and corrosion-preservative agents described in the above examples and comparative examples were incorporated into cement mortar. The cement used was reference cement, the fine aggregate was standard sand or medium-grade sand, and the water was tap water. The corrosion resistance coefficient, expansion coefficient, chloride ion diffusion coefficient ratio, and compressive strength ratio of the cement mortar were tested according to the relevant provisions of JCT1011-2021 "Concrete Anti-corrosion and Corrosion-preservative Agents" and GB / T 23439-2017 "Concrete Expansion Agents". The cement mortar mold dimensions were 40mm × 40mm × 160mm, and a YAW-300E fully automatic pressure testing machine was used with a loading speed of 2.4kN / s. Specific performance test results are shown in Table 1.

[0059] Unless otherwise specified, all other raw materials or processing techniques are conventional commercial products or conventional processing techniques in this field.

[0060] Example 1

[0061] The powder from crushed concrete was passed through a 200-mesh sieve. 200g of the sieved powder was then weighed and immersed in a dilute HCl solution (pH=2) for 24 hours. After immersion, the powder was washed four times with water and dried in a 60℃ drying oven to obtain regenerated micro-powder. This process primarily aims to acquire more hydroxyl groups (-OH) on the surface of the regenerated micro-powder. Solution A was prepared by mixing 83.3g of tetraethyl orthosilicate and 300ml of anhydrous ethanol. Solution B was prepared by mixing 28.8g of deionized water, 100g of regenerated micro-powder, and 300ml of anhydrous ethanol in a beaker and stirring for 30 minutes. Solution B was prepared by mixing 17.5g of ammonia, 40g of polyethylene glycol, and a portion of anhydrous ethanol and stirring for 20 minutes.

[0062] Then, the mixed solution B was stirred with the regenerated micro powder mixture for 30 min to obtain mixture B1. Mixture B1 was placed in a water bath, and solution A was placed in a separatory funnel. Solution A was added dropwise to mixture B1 at a rate of 2 h / min. During the dropwise addition, mixture B1 was continuously stirred at a stirring speed of 800 rap / min, the water bath reaction temperature was 60℃, and the reaction time was 8 h. After the reaction was completed, the mixed solution in the beaker was allowed to stand and age for 24 h. After aging, the reactants were washed four times with EtOH or deionized water, and then dried in a drying oven at 40℃ to finally obtain powder with in-situ grafted nano-silica on the surface of the regenerated micro powder, i.e., nano-modified regenerated micro powder.

[0063] Next, the above-mentioned nano-modified recycled powder, expansion component, anti-corrosion component, water-reducing component, and barium ion-based polyethylene glycol ion curing agent were each passed through a 300-mesh sieve, and the mass of each raw material was weighed according to the raw material mixing ratio, as shown below:

[0064] 44 parts of nano-modified recycled micro powder;

[0065] The expansion component consists of 43 parts, wherein the mass ratio of sulfoaluminate type expansion agent powder to zeolite powder is 80:20; the specific surface area of ​​the expansion agent is 320 m². 2 / kg, magnesium oxide content ≤5.0%, total alkali content ≤0.75%, zeolite powder particle size 50μm, natural zeolite content 70%;

[0066] The preservative component is 6.5 parts, wherein the mass ratio of calcium stearate: sodium benzoate: acrylate is 50:35:15.

[0067] 0.5 parts of water-reducing component, which is polycarboxylate superplasticizer powder.

[0068] 6 parts of barium ion-based polyethylene glycol ion curing agent.

[0069] The raw materials, nano-modified recycled micro powder, expansion component, anti-corrosion component, water-reducing agent and barium ion-based polyethylene glycol ion curing agent are placed in a dry mixing machine and mixed evenly to obtain a concrete anti-erosion and anti-corrosion agent based on nano-modified recycled micro powder.

[0070] Add 10% by weight of a nano-modified recycled micro-powder concrete anti-corrosion agent to the cement.

[0071] Example 2

[0072] The preparation method is basically the same as that in Example 1, except that:

[0073] 42 parts of nano-modified recycled micro powder;

[0074] The expansion component consists of 43 parts, wherein the mass ratio of the expansion agent to zeolite powder is 80:20.

[0075] The preservative component is 6.5 parts, wherein the mass ratio of calcium stearate: sodium benzoate: acrylate is 50:35:15;

[0076] 0.5 parts of water-reducing component;

[0077] 8 parts of barium ion-based polyethylene glycol ion curing agent.

[0078] Example 3

[0079] The preparation method is basically the same as that in Example 1, except that:

[0080] 40 parts of nano-modified recycled micro powder;

[0081] The expansion component consists of 43 parts, wherein the mass ratio of the expansion agent to zeolite powder is 80:20.

[0082] The preservative component is 6.5 parts, wherein the mass ratio of calcium stearate: sodium benzoate: acrylate is 50:35:15;

[0083] 0.5 parts of water-reducing component;

[0084] 10 parts of barium ion-based polyethylene glycol ion curing agent.

[0085] Example 4

[0086] The preparation method is basically the same as that in Example 1, except that:

[0087] 38 parts of nano-modified recycled micro powder;

[0088] The expansion component consists of 43 parts, wherein the mass ratio of the expansion agent to zeolite powder is 80:20.

[0089] The preservative component is 6.5 parts, wherein the mass ratio of calcium stearate: sodium benzoate: acrylate is 50:35:15;

[0090] 0.5 parts of water-reducing component;

[0091] 12 parts of barium ion-based polyethylene glycol ion curing agent.

[0092] Example 5

[0093] The preparation method is basically the same as that in Example 1, except that:

[0094] 30 parts of nano-modified recycled micro powder;

[0095] The expansion component is 50 parts, wherein the mass ratio of the expansion agent to zeolite powder is 80:20;

[0096] The preservative component consists of 7 parts, wherein the mass ratio of calcium stearate, sodium benzoate, and acrylate is 50:35:15.

[0097] 1 part of water-reducing component;

[0098] 12 parts of barium ion-based polyethylene glycol ion curing agent.

[0099] Example 6

[0100] The preparation method is basically the same as that in Example 1, except that:

[0101] 50 parts of nano-modified recycled micro powder;

[0102] The expansion component is 40 parts, wherein the mass ratio of the expansion agent to zeolite powder is 80:20;

[0103] The preservative component consists of 5 parts, wherein the mass ratio of calcium stearate, sodium benzoate, and acrylate is 50:35:15.

[0104] Two parts of water-reducing component;

[0105] Three parts of barium ion-based polyethylene glycol ion curing agent.

[0106] Example 7

[0107] A method for preparing a concrete anti-erosion agent (the concrete anti-erosion agent is a nano-modified recycled micro powder concrete anti-erosion and corrosion inhibitor), the method comprising the following steps:

[0108] (1) The specific preparation process of the nano-modified regenerated micro powder is as follows:

[0109] S1: The powder from crushed concrete is passed through a 200-mesh sieve. After sieving, 200g of the powder is weighed and immersed in a dilute HCl solution with pH=2 for 24 hours. After immersion, the powder is washed four times with water and then dried in a 60℃ drying oven to obtain regenerated micro powder. This process is mainly to allow more hydroxyl groups (-OH) to be acquired on the surface of the regenerated micro powder.

[0110] S2: Weigh 83.3g of tetraethyl orthosilicate and mix with 300ml of anhydrous ethanol to obtain solution A; weigh 28.8g of deionized water, 100g of regenerated micro powder and 300ml of anhydrous ethanol, mix them in a beaker and stir for 30min to obtain a regenerated micro powder mixture;

[0111] S3: Weigh 17.5g of ammonia, 40g of polyethylene glycol and a portion of anhydrous ethanol and mix them. Stir for 20 minutes to obtain mixed solution B. Then, mix mixed solution B with the regenerated micro powder mixture for 30 minutes to obtain mixture B1.

[0112] S4: Place mixture B1 in a water bath and solution A in a separatory funnel. Add solution A dropwise to mixture B1 at a rate of 2 drops per hour. During the dropwise addition, continuously stir mixture B1 at a stirring speed of 800 rpm. The water bath reaction temperature is 60°C, and the reaction time is 8 hours. After the reaction is complete, allow the mixed solution in the beaker to stand and age for 24 hours.

[0113] S5: After aging, the reactants are washed four times with EtOH or deionized water, and then dried in a drying oven at 40°C. Finally, the powder with nano-silica grafted onto the surface of the regenerated micro powder is obtained, which is the nano-modified regenerated micro powder.

[0114] (2) The nano-modified recycled powder, expansion component, anti-corrosion component, water-reducing component, and barium ion-based polyethylene glycol ion curing agent were each passed through a 300-mesh sieve, and the mass of each raw material was weighed according to the raw material mixing ratio, as shown below:

[0115] 44 parts of nano-modified recycled micro powder;

[0116] The expanding component consists of 43 parts, wherein the mass ratio of sulfoaluminate-type expanding agent powder to zeolite powder is 80:20; the specific surface area of ​​the expanding agent is 320 m². 2 / kg, magnesium oxide content ≤5.0%, total alkali content ≤0.75%, zeolite powder particle size 50μm, natural zeolite content 70%;

[0117] The preservative component is 6.5 parts, wherein the mass ratio of calcium stearate: sodium benzoate: acrylate is 50:35:15.

[0118] 0.5 parts of water-reducing component, which is polycarboxylate superplasticizer powder.

[0119] 6 parts of barium ion-based polyethylene glycol ion curing agent.

[0120] (3) Place the raw materials nano-modified recycled micro powder, expansion component, anti-corrosion component, water-reducing agent and barium ion-based polyethylene glycol ion curing agent from step (2) into a dry mixing machine and mix evenly to obtain a concrete anti-erosion and anti-corrosion agent based on nano-modified recycled micro powder.

[0121] Testing showed that the nano-modified recycled micro-powder concrete anti-corrosion agent prepared in this embodiment, when incorporated into concrete (at a dosage of 8%), achieved a 28-day compressive strength of 106.8%, a Cl- diffusion coefficient of 0.72, a corrosion resistance coefficient of 1.26, and an expansion coefficient of 1.08, meeting the requirements of JCT1011-2021 and GB / T 23439-2017 standards.

[0122] Comparative Example 1

[0123] 44 parts of regenerated micro powder:

[0124] The expansion component consists of 43 parts, wherein the mass ratio of the expansion agent to zeolite powder is 80:20.

[0125] The preservative component is 6.5 parts, wherein the mass ratio of calcium stearate: sodium benzoate: acrylate is 50:35:15;

[0126] 0.5 parts of water-reducing component;

[0127] 6 parts of barium ion-based polyethylene glycol ion curing agent.

[0128] In other words, compared with Example 1, the anti-corrosion and corrosion-resistant agent for nano-modified recycled micro powder concrete in Comparative Example 1 did not involve nano-modification of the recycled micro powder.

[0129] Comparative Example 2

[0130] 50 parts of nano-modified recycled micro powder:

[0131] The expansion component consists of 43 parts, wherein the mass ratio of the expansion agent to zeolite powder is 80:20.

[0132] The preservative component is 6.5 parts, wherein the mass ratio of calcium stearate: sodium benzoate: acrylate is 50:35:15;

[0133] 0.5 parts of water-reducing component;

[0134] In other words, compared to Example 1, the nano-modified recycled micro-powder concrete anti-corrosion agent of Comparative Example 2 does not contain barium ion-based polyethylene glycol ion curing agent.

[0135] Table 1 shows the specific performance test results of different embodiments and comparative examples.

[0136]

[0137]

[0138] As can be seen from the data in Table 1 above and the comparative analysis of the formulations of each embodiment, the anti-erosion and corrosion-resistant concrete agent based on nano-modified recycled micropowder provided in this application exhibits significant improvements in anti-erosion performance and optimization of density under the regulation of nano-modified recycled micropowder and barium ion-based polyethylene glycol ion curing agent, as shown in the following specific manifestations:

[0139] (1) Synergistic effect mechanism of functional components

[0140] In each embodiment, the corrosion-resistant components were fixed at 50:35:15: calcium stearate: sodium benzoate: acrylate. The synergistic effect of its hydrophobic barrier (calcium stearate), microbial inhibition (sodium benzoate), and flexible reinforcement (acrylate) resulted in a corrosion resistance coefficient that was generally higher than that of Comparative Example 1 (1.08). In particular, in Example 4, the corrosion resistance coefficient reached 1.32, indicating that the "triple protection" mechanism at this ratio was significantly effective in resisting sulfate attack.

[0141] The coefficients of thermal expansion in Examples 1 to 4 increased from 1.02 to 1.12, all lower than the 1.20 of Comparative Example 1 and far below the standard limit (≤1.5). This indicates that the ionic curing agent and the expanding components (sulfoaluminate expanding agent + zeolite powder) form a synergistic effect: the expanding agent compensates for shrinkage, the zeolite powder adsorbs excess moisture, and the ionic curing agent inhibits excessive expansion by filling, thus avoiding the microstructural stress imbalance caused by the lack of curing agent in Comparative Example 1.

[0142] Compared to unmodified recycled micro powder ( Figure 1 Comparative Example 1 (28-day compressive strength ratio 101.6%), nano-modified regenerated micropowder ( Figure 2 The introduction of ) increases the 28-day strength to 107.4%-112.8%, and its core mechanism lies in the in-situ grafting of nano-SiO2 (particle size of about 20-50nm) onto the surface of the regenerated micro powder. Figure 3 Through the volcanic ash effect and the filling effect of micro-aggregates, the structure of the transition zone (ITZ) between the cement matrix and aggregates is optimized, the porosity of the ITZ is reduced, and the high specific surface area of ​​the nanoparticles significantly enhances the crosslinking density of the hydration products.

[0143] (2) Gradient optimization of the performance of barium ion-based polyethylene glycol ion curing agent

[0144] As the amount of barium ion-based polyethylene glycol ion curing agent increased from 6 parts (Example 1) to 12 parts (Example 4), the chloride ion diffusion coefficient ratio decreased from 0.78 to 0.68 (a decrease of 12.8%), and both were better than the standard requirement (≤0.85). This indicates that the barium ion-based polyethylene glycol curing agent effectively inhibits Cl- migration by forming a stable complex through coordination bonding with Cl- and combining the steric hindrance effect of the polyethylene glycol molecular chain. In contrast, Comparative Example 1 (without barium ion-based polyethylene glycol ion curing agent) had a chloride ion diffusion coefficient ratio of 0.80, which, while meeting the standard, was inferior to the examples, further verifying the necessity of ion curing technology.

[0145] Comparative Example 2, without the addition of barium ion-based polyethylene glycol ion curing agent, exhibited the lowest chloride ion diffusion coefficient (0.82) and corrosion resistance coefficient (0.96) among the examples, while its expansion coefficient (1.18) was relatively high. This indicates that the key role of the ion curing agent is that the lack of barium ion complexation and filling effect leads to increased Cl- permeability and decreased resistance to chemical corrosion. Furthermore, the absence of the ion curing agent results in insufficient adsorption capacity of zeolite powder, the expansion agent effect is not adequately buffered, and the risk of microcracks increases.

[0146] Most importantly, this application is environmentally friendly while improving performance, with a recycled micro-powder utilization rate of 40%-44%, reducing carbon emissions by 120-150 kg CO2-eq per ton of corrosion inhibitor, and posing no risk of heavy metal pollution. Example 4 exhibits the best overall performance (28-day strength ratio of 112.8%, chloride ion diffusion coefficient ratio of 0.68), fully validating the engineering feasibility of synergistic regulation by nano-modification and ion-curing agents, providing an innovative solution for long-life protection of concrete structures in harsh environments. Compared to traditional corrosion inhibitors (such as Comparative Example 1), this application can significantly extend the service life of concrete and reduce maintenance costs in harsh marine environments, demonstrating outstanding engineering applicability.

[0147] This application, through integrated material-structure-function design, overcomes the technical bottlenecks of traditional anti-corrosion systems, such as single-effect limitations and high environmental load, providing an innovative solution for improving the durability of concrete structures in harsh environments such as marine engineering and saline soil areas. The multi-mechanism synergistic protection system, a compound of calcium stearate, sodium benzoate, and acrylate, combines a triple mechanism of "physical impermeability, biological inhibition, and chemical strengthening" to achieve the protection against Cl- and SO42-. 2 - And comprehensive resistance to microbial erosion. Highly active component design: Synergistic effect of nano-modified recycled micropowder and sulfoaluminate expanding agent - zeolite powder, improving density and volume stability. Green ion solidification technology: Enzyme-catalyzed synthesis of barium ion-based polyethylene glycol solidifying agent, which, through coordination bonding, permanently fixes corrosive ions, reducing the Cl- diffusion coefficient by more than 50%. Solid waste resource utilization: Efficient incorporation of industrial waste residues such as recycled micropowder and barium slag powder reduces production costs and promotes the development of low-carbon building materials. Therefore, this application has broad market application prospects.

[0148] In the description of this application, unless otherwise expressly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0149] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0150] In the description of this embodiment, the terms "upper," "lower," "left," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0151] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. The preferred embodiments have been described in detail. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this application without departing from the spirit and scope of the technical solutions of this application, and all such modifications and substitutions should be covered within the scope of the claims of this application.

Claims

1. A nano-modified recycled micro-powder concrete anti-erosion and corrosion-resistant agent, characterized in that, By weight, it includes the following components: 30-50 parts of nano-modified recycled micro powder; 40-50 parts of the expanding component; 5-10 parts of anti-corrosion component; Water-reducing component: 0.5-2 parts; 3-12 parts of barium ion-based polyethylene glycol ion curing agent.

2. The anti-corrosion and corrosion-resistant agent for concrete based on nano-modified recycled micro-powder according to claim 1, characterized in that, The nano-modified recycled powder is nano-silica grafted onto the surface of recycled powder in situ; and / or, the nano-modified recycled powder is powder with a particle size of less than 75μm after the recycled concrete is crushed.

3. The anti-corrosion and corrosion-resistant agent for concrete based on nano-modified recycled micro-powder according to claim 1, characterized in that, The expansion component is composed of a sulfoaluminate type expansion agent and zeolite powder in a mass ratio of (60-90):(10-40); The sulfoaluminate type expanding agent is in powder form with a specific surface area > 300 m². 2 / kg, MgO content ≤5.0%, total alkali content ≤0.75%; The zeolite powder has a particle size of <60μm and a natural zeolite content of >65%.

4. The anti-corrosion and corrosion-resistant agent for concrete based on nano-modified recycled micro-powder according to claim 1, characterized in that, The preservative component is composed of calcium stearate, sodium benzoate and acrylate in a mass ratio of (30-50):(10-30):(20-40).

5. The anti-corrosion and corrosion-resistant agent for concrete based on nano-modified recycled micro-powder according to claim 1, characterized in that, The water-reducing component is one of the following: powdered polycarboxylic acid, naphthalene sulfonic acid, or aminosulfonic acid water-reducing agents; And / or, the barium ion-based polyethylene glycol ion curing agent is formed by linking barium ions to polyethylene glycol molecules, wherein the polyethylene glycol has a molecular weight of 800 to 10000 Da, and the barium ions are derived from at least one of barium nitrate, barium chloride, or barium slag powder.

6. The anti-corrosion and corrosion-resistant agent for concrete based on nano-modified recycled micro-powder according to claim 1, characterized in that, The nano-modified recycled micro powder is grafted with nano-silica in situ, and the nano-modified recycled micro powder concrete anti-corrosion agent is prepared by hydrolysis and condensation reaction of recycled micro powder, tetraethyl orthosilicate, deionized water, anhydrous ethanol, and ammonia.

7. The preparation method of the nano-modified recycled micro-powder concrete anti-erosion and corrosion inhibitor according to any one of claims 1 to 6, wherein the preparation method comprises: Preparation of nano-modified regenerated micro powders; Weigh the mass of each raw material according to the mixing ratio of nano-modified recycled micro powder, expansion component, anti-corrosion component, water-reducing component and barium ion-based polyethylene glycol ion curing agent. After mixing the above raw materials evenly, a nano-modified recycled micro powder concrete anti-erosion and anti-corrosion agent is obtained.

8. The preparation method according to claim 7, characterized in that, The preparation of the above-mentioned nano-modified regenerated micro powder includes: using tetraethyl orthosilicate, anhydrous ethanol, polyethylene glycol, deionized water and ammonia as raw materials, and realizing in-situ grafting of nano-silica onto the surface of the regenerated micro powder through a hydrolysis condensation reaction; in the hydrolysis condensation reaction, anhydrous ethanol is used as a co-solvent, ammonia is used as a catalyst, and polyethylene glycol is used as a surfactant.

9. The preparation method according to claim 7, characterized in that, The anti-corrosion component is added to the concrete as an admixture to replace part of the cement, and its dosage is 6 to 12% of the cement mass.

10. The application of the nano-modified recycled micro-powder concrete anti-corrosion and corrosion-resistant agent as described in any one of claims 1 to 6, characterized in that, It is used in cross-sea bridges, deep-sea platforms, or dock structures.

Images