A concrete surface enhancer, its preparation method and application

Abstract

This invention discloses a concrete surface enhancer, its preparation method, and its application, belonging to the field of building materials technology. It mainly comprises the following raw materials in the following weight ratios: 10-25 wt% lithium-based penetrant, 3-10 wt% silicone resin, 3-10 wt% epoxy resin emulsion, 2-5 wt% sodium sulfate, 2-5 wt% latex powder, 1-5 wt% modified microcrystalline cellulose, 1-5 wt% talc, 0.1-1 wt% film-forming aid, and 0.1-0.5 wt% defoamer, with the remainder being water. The concrete surface enhancer provided by this invention is based on lithium-based penetrant, silicone resin, and epoxy resin emulsion, which possess strong adhesion, convenient curing, strong chemical stability, and high inherent strength. It is externally mixed with sodium sulfate, latex powder, modified microcrystalline cellulose, talc, film-forming aid, and defoamer. When applied to the concrete surface, it effectively improves the pore structure of the concrete, making the microstructure of the concrete surface denser, improving the surface strength and durability of the concrete, and solving the safety hazards caused by cracks in the concrete.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, specifically to a concrete surface enhancer, its preparation method, and its application. Background Technology

[0002] With the rapid development of high-speed railways in my country, concrete has become one of the most widely used materials in high-speed railway construction. The substructure of bridges and precast box girders are prominent structures in high-speed railways. Due to fluctuations in the quality of raw materials such as sand and stone, freshly mixed concrete is prone to poor workability, such as segregation, bleeding, dryness, and hardening. Furthermore, deviations in formwork and reinforcement fabrication, as well as improper operations in pouring, vibration, molding, and curing, can all cause defects in the appearance quality of the structure.

[0003] Common defects in the appearance of concrete structures include: honeycombing, pitting, exposed reinforcement, surface voids, microcracks, and low surface strength. During on-site construction, no matter how much management is improved, concrete defects are still difficult to avoid. The influencing factors are complex, and surface defects can easily occur during the concrete pouring process, shortly after construction, or when surface curing is not timely. Therefore, timely inspection and repair are essential after formwork removal.

[0004] In the past, the focus was mainly on the strength of concrete structures, but today, with increasingly higher quality requirements, the appearance quality of concrete has received widespread attention from engineering and technical personnel in various industries. Summary of the Invention

[0005] The purpose of this invention is to provide a concrete surface enhancer, its preparation method, and its application, which solves the problem of defects such as cracks appearing on the surface of concrete.

[0006] This invention is achieved through the following technical solution:

[0007] The present invention provides a concrete surface strengthening agent, which mainly comprises the following raw materials in the following weight ratio:

[0008] The composition consists of 10-25 wt% lithium-based permeate, 3-10 wt% silicone resin, 3-10 wt% epoxy resin emulsion, 2-5 wt% sodium sulfate, 2-5 wt% latex powder, 1-5 wt% modified microcrystalline cellulose, 1-5 wt% talc, 0.1-1 wt% film-forming aid, and 0.1-0.5 wt% defoamer, with the remainder being water.

[0009] Furthermore, the concrete surface enhancer mainly comprises the following raw materials in the following weight ratios:

[0010] The composition consists of 15-20 wt% lithium-based permeate, 5-7 wt% silicone resin, 5-8 wt% epoxy resin emulsion, 3-4 wt% sodium sulfate, 3-4 wt% latex powder, 2-4 wt% modified microcrystalline cellulose, 2-4 wt% talc, 0.3-0.7 wt% film-forming aid, and 0.2-0.4 wt% defoamer, with the remainder being water.

[0011] Furthermore, the concrete surface enhancer mainly comprises the following raw materials in the following weight ratios:

[0012] The composition consists of 17 wt% lithium-based permeate, 5.5 wt% silicone resin, 6 wt% epoxy resin emulsion, 3.5 wt% sodium sulfate, 3.5 wt% latex powder, 3 wt% modified microcrystalline cellulose, 2.5 wt% talc, 0.5 wt% film-forming aid, and 0.3-0.1-0.5 wt% defoamer, with the remainder being water.

[0013] Furthermore, in the concrete surface strengthening agent, the preparation of the lithium-based penetrating liquid includes: adding sodium methylsilicate and nano-silica to an aqueous solution of lithium polysilicate, and after the mixture is evenly dispersed, heating it to 50-70°C, stirring and reacting for 1-2 hours, adding ammonium bisulfate and continuing to stir for 0.5-1 hours to obtain the lithium-based penetrating liquid;

[0014] The mass ratio of lithium polysilicate, sodium methylsilicate, nano lithium bentonite, and ammonium bisulfate is 2:(0.8-1.5):(0.1-0.5):(0.1-0.3).

[0015] Furthermore, in the concrete surface reinforcing agent, the preparation of the modified microcrystalline cellulose includes:

[0016] Microcrystalline cellulose was added to a phenolic resin solution and stirred until homogeneous. Then, sodium alkali lignin carboxylate was added and stirred at 50℃-70℃ for 2-3 hours. After filtration and drying, modified microcrystalline cellulose was obtained.

[0017] The mass ratio of microcrystalline cellulose, phenolic resin, and sodium alkali lignin carboxylate is 1:(0.5-0.8):(0.3-0.5).

[0018] Furthermore, in the concrete surface enhancer, the film-forming aid includes one or more of the following: dodecyl alcohol ester, ethylene glycol butyl ether, and hexanediol butyl ether acetate.

[0019] Furthermore, in the concrete surface strengthening agent, the defoamer includes one or more of the following: polyoxypropylene polyoxyethylene glycerol ether, polyoxypropylene glycerol ether, polyoxyethylene ether, polyoxyethylene polyoxypropylene pentaerythritol ether, and polyoxyethylene polyoxypropylene alcohol ether.

[0020] The present invention also provides a method for preparing the above-mentioned concrete surface enhancer, comprising:

[0021] The lithium-based permeating solution, silicone resin, and epoxy resin emulsion were stirred and mixed evenly to obtain an initial mixture.

[0022] Sodium sulfate, latex powder, modified microcrystalline cellulose, and talc are added to water and stirred evenly. Then, while stirring, the mixture is added to the initial mixture and stirred evenly. Finally, film-forming aid and defoamer are added and stirring is continued for 10-20 minutes to obtain the concrete surface enhancer.

[0023] This invention also provides the application of the above-mentioned concrete surface enhancer in concrete crack repair mortar.

[0024] Furthermore, the concrete surface enhancer is added to the concrete crack repair mortar at a rate of 5-10 wt%.

[0025] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0026] 1. The concrete surface enhancer provided by this invention is a water-based formulation. When applied to the concrete surface, it reduces the adsorption of the concrete surface, minimizing the absorption of harmful substances that could affect the concrete's durability. This concrete surface enhancer has strong permeability, penetrating to a maximum depth of over 5mm into the concrete. On one hand, it undergoes a secondary hydration reaction with free calcium ions within the concrete, generating water-insoluble calcium sulfate crystals, ettringite, and calcium silicate gel, thereby increasing the density of the concrete surface. On the other hand, it penetrates into the concrete, forming a film both inside and on the surface, further enhancing the density of the concrete structure, reducing porosity, improving the pore structure and microcracks, thus improving the surface strength and durability of the concrete and solving the problems of cracks and low surface strength present on the concrete surface.

[0027] 2. The concrete surface enhancer provided by this invention utilizes lithium-based penetrating liquid to effectively block micro-cracks and capillary voids inside concrete, giving the concrete structure a durable waterproof function, better density and compressive strength, and deep penetration. It also effectively prevents acidic substances from eroding the concrete. Specifically, the molecular structure of sodium methylsilicate contains both polar silicate groups, which have good compatibility with lithium polysilicate, and non-polar methyl groups, which provide a water-repellent effect. The addition of ammonium bisulfate increases the modulus of sodium silicate, thereby improving its water resistance and allowing for better bonding between lithium silicate and sodium silicate. Nano-lithium saponin gives the particle surface a permanent negative charge, further enhancing the stability of lithium silicate and sodium silicate and preventing pulverization.

[0028] 3. The concrete surface enhancer provided by the present invention modifies microcrystalline cellulose by using phenolic resin and sodium alkali lignin carboxylate to modify microcrystalline cellulose, which can improve the permeability of the concrete surface enhancer in concrete cracks and form colloidal silicates with cement hydration products in the pores of the surface, filling the pores of the concrete surface.

[0029] 4. The concrete surface enhancer of the present invention can also be used in concrete crack repair mortar. It has a repairing effect on concrete cracks with a width of 0.3 to 2.5 mm, which can solve the problems of low concrete surface strength and cracks on the concrete surface in actual engineering, enhance the stability of the overall concrete structure, and extend the service life of concrete. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The illustrative embodiments and descriptions of this invention are for explanation only and are not intended to limit the invention. Unless otherwise specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0031] The technical solution of this invention is as follows:

[0032] A concrete surface enhancer mainly comprises the following raw materials in the following weight ratio:

[0033] The composition consists of 10-25 wt% lithium-based permeate, 3-10 wt% silicone resin, 3-10 wt% epoxy resin emulsion, 2-5 wt% sodium sulfate, 2-5 wt% latex powder, 1-5 wt% modified microcrystalline cellulose, 1-5 wt% talc, 0.1-1 wt% film-forming aid, and 0.1-0.5 wt% defoamer, with the remainder being water.

[0034] The concrete surface enhancer provided by this invention is a water-based formulation. When applied to the concrete surface, it reduces the surface's adsorption capacity, minimizing the absorption of harmful substances that could negatively impact the concrete's durability. This concrete surface enhancer exhibits strong permeability, penetrating to a maximum depth of over 5mm into the concrete. On one hand, it undergoes a secondary hydration reaction with free calcium ions within the concrete, generating water-insoluble calcium sulfate crystals, ettringite, and calcium silicate gel, thereby increasing the concrete surface's density. On the other hand, it penetrates the concrete interior, forming a film both internally and on the surface, further enhancing the concrete structure's density, reducing porosity, improving the pore structure and reducing microcracks, thus improving the concrete's surface strength and durability. This solves the problems of surface cracks and low surface strength present in concrete.

[0035] The concrete surface enhancer provided by this invention is based on lithium-based penetrating liquid, organosilicon resin, and epoxy resin emulsion, which have strong adhesion, convenient curing, strong chemical stability, and high self-strength. It is externally mixed with sodium sulfate, latex powder, modified microcrystalline cellulose, talc powder, film-forming aid, and defoamer. When applied to the concrete surface, it can effectively improve the pore structure of the concrete, make the microstructure of the concrete surface more compact, improve the surface strength and durability of the concrete, and solve the safety hazards caused by cracks in the concrete.

[0036] The concrete surface enhancer of this invention also has a certain repair capability and can be used in concrete crack repair mortar, which can enhance the stability of the overall concrete structure and extend the service life of concrete.

[0037] The preparation of the lithium-based permeate includes: adding sodium methylsilicate and nano-silica to an aqueous solution of lithium polysilicate, and after the mixture is evenly dispersed, heating it to 50-70°C, stirring and reacting for 1-2 hours, adding ammonium bisulfate and continuing to stir for 0.5-1 hours to obtain the lithium-based permeate;

[0038] The mass ratio of lithium polysilicate, sodium methylsilicate, nano lithium bentonite, and ammonium bisulfate is 2:(0.8-1.5):(0.1-0.5):(0.1-0.3).

[0039] The lithium-based penetrating liquid provided by this invention effectively blocks micro-cracks and capillary voids inside concrete, giving the concrete structure a durable waterproof function, better density and compressive strength, and a deep penetration depth. At the same time, it can also effectively prevent acidic substances from corroding the concrete.

[0040] In the lithium-based permeating solution provided by this invention, the molecular structure of sodium methylsilicate contains both polar silicate groups, which have good compatibility with lithium polysilicate, and non-polar methyl groups, which can play a water-repellent role. The addition of ammonium bisulfate is used to increase the modulus of sodium silicate, thereby improving the water resistance of sodium silicate, and at the same time, it enables lithium silicate and sodium silicate to bond well.

[0041] The disc-shaped structure of nano-lithium bentonite results in a double charge distribution, with negative charges on both sides of the disc-shaped particles and positive charges at the edges. Nano-lithium bentonite belongs to a 2:1 type silicate mineral structure, with each layer consisting of two parallel silicon-oxygen tetrahedra sandwiching a magnesium-oxygen octahedron. On each side of the magnesium-oxygen octahedron, there is a silicon-oxygen tetrahedron sharing an oxygen atom. Some of the divalent magnesium atoms are replaced by monovalent lithium atoms, giving the particle surface a permanent negative charge. This is more conducive to the stability of lithium silicate and sodium silicate, preventing pulverization.

[0042] The preparation of the modified microcrystalline cellulose includes:

[0043] Microcrystalline cellulose was added to a phenolic resin solution and stirred until homogeneous. Then, sodium alkali lignin carboxylate was added and stirred at 50℃-70℃ for 2-3 hours. After filtration and drying, modified microcrystalline cellulose was obtained.

[0044] The mass ratio of microcrystalline cellulose, phenolic resin, and sodium alkali lignin carboxylate is 1:(0.5-0.8):(0.3-0.5).

[0045] The modified microcrystalline cellulose of the present invention uses phenolic resin and sodium alkali lignin carboxylate to modify the microcrystalline cellulose, which can improve the permeability of concrete surface enhancers in concrete cracks and can form colloidal silicates with cement hydration products in the pores of the surface, filling the pores of the concrete surface.

[0046] A method for preparing a concrete surface enhancer, comprising:

[0047] The lithium-based permeating solution, silicone resin, and epoxy resin emulsion were stirred and mixed evenly to obtain an initial mixture.

[0048] Sodium sulfate, latex powder, modified microcrystalline cellulose, and talc are added to water and stirred evenly. Then, while stirring, the mixture is added to the initial mixture and stirred evenly. Finally, film-forming aid and defoamer are added and stirring is continued for 10-20 minutes to obtain the concrete surface enhancer.

[0049] The concrete surface enhancer of the present invention can also be used in concrete crack repair mortar, and has a repairing effect on concrete cracks with a width of 0.3 to 2.5 mm. It can solve the problems of low concrete surface strength and cracks on the concrete surface in actual engineering, enhance the stability of the overall concrete structure, and extend the service life of concrete.

[0050] To further illustrate the present invention, the following description, in conjunction with embodiments, describes a concrete surface enhancer provided by the present invention. However, it should be understood that these embodiments are implemented under the premise of the technical solution of the present invention, and provide detailed implementation methods and specific operating procedures. They are only for further illustrating the features and advantages of the present invention, and are not intended to limit the scope of the claims of the present invention. The scope of protection of the present invention is not limited to the following embodiments.

[0051] In the following examples, the film-forming aid is dodecyl alcohol ester; the defoamer is polyoxypropylene polyoxyethylene glycerol ether.

[0052] Example 1:

[0053] This embodiment of a concrete surface strengthening agent mainly comprises the following raw materials in the following weight ratios:

[0054] The composition consists of 10 wt% lithium-based permeate, 3 wt% silicone resin, 3 wt% epoxy resin emulsion, 2 wt% sodium sulfate, 2 wt% latex powder, 1 wt% modified microcrystalline cellulose, 1 wt% talc, 0.1 wt% film-forming aid, and 0.1 wt% defoamer, with the remainder being water.

[0055] The preparation of the lithium-based permeate includes: adding sodium methylsilicate and nano-silica to an aqueous solution of lithium polysilicate, and after the mixture is evenly dispersed, heating it to 50°C, stirring and reacting for 1 hour, adding ammonium bisulfate and stirring for another 0.5 hours to obtain the lithium-based permeate;

[0056] The mass ratio of lithium polysilicate, sodium methylsilicate, nano lithium bentonite, and ammonium bisulfate is 2:0.8:0.1:0.1.

[0057] The preparation of the modified microcrystalline cellulose includes:

[0058] Microcrystalline cellulose was added to a phenolic resin solution and stirred until homogeneous. Then, sodium alkali lignin carboxylate was added, and the mixture was stirred and reacted at 50°C for 2 hours. After filtration and drying, modified microcrystalline cellulose was obtained.

[0059] The mass ratio of microcrystalline cellulose, phenolic resin, and sodium alkali lignin carboxylate is 1:0.5:0.3.

[0060] This embodiment describes a method for preparing a concrete surface enhancer, comprising:

[0061] The lithium-based permeating solution, silicone resin, and epoxy resin emulsion were stirred and mixed evenly to obtain an initial mixture.

[0062] Sodium sulfate, latex powder, modified microcrystalline cellulose, and talc are added to water and stirred evenly. Then, while stirring, the mixture is added to the initial mixture and stirred evenly. Finally, film-forming aid and defoamer are added and stirring is continued for 10-20 minutes to obtain the concrete surface enhancer.

[0063] Example 2:

[0064] This embodiment of a concrete surface strengthening agent mainly comprises the following raw materials in the following weight ratios:

[0065] The composition consists of 15 wt% lithium-based permeate, 5 wt% silicone resin, 5 wt% epoxy resin emulsion, 3 wt% sodium sulfate, 3 wt% latex powder, 2 wt% modified microcrystalline cellulose, 2 wt% talc, 0.3 wt% film-forming aid, and 0.2 wt% defoamer, with the remainder being water.

[0066] The preparation of the lithium-based permeate includes: adding sodium methylsilicate and nano-silica to an aqueous solution of lithium polysilicate, and after the mixture is evenly dispersed, heating it to 60°C, stirring and reacting for 1.5 h, adding ammonium bisulfate and stirring for another 0.5 h to obtain the lithium-based permeate;

[0067] The mass ratio of lithium polysilicate, sodium methylsilicate, nano lithium bentonite, and ammonium bisulfate is 2:(1:0.3:0.2).

[0068] The preparation of the modified microcrystalline cellulose includes:

[0069] Microcrystalline cellulose was added to a phenolic resin solution and stirred until homogeneous. Then, sodium alkali lignin carboxylate was added, and the mixture was stirred and reacted at 60°C for 3 hours. After filtration and drying, modified microcrystalline cellulose was obtained.

[0070] The mass ratio of microcrystalline cellulose, phenolic resin, and sodium alkali lignin carboxylate is 1:0.6:0.4.

[0071] The preparation method of the concrete surface enhancer in this embodiment is the same as that in Embodiment 1.

[0072] Example 3:

[0073] This embodiment of a concrete surface strengthening agent mainly comprises the following raw materials in the following weight ratios:

[0074] The composition consists of 17 wt% lithium-based permeate, 5.5 wt% silicone resin, 6 wt% epoxy resin emulsion, 3.5 wt% sodium sulfate, 3.5 wt% latex powder, 3 wt% modified microcrystalline cellulose, 2.5 wt% talc, 0.5 wt% film-forming aid, and 0.3-0.1-0.5 wt% defoamer, with the remainder being water.

[0075] The preparation of the lithium-based permeate includes: adding sodium methylsilicate and nano-silica to an aqueous solution of lithium polysilicate, and after the mixture is evenly dispersed, heating it to 70°C, stirring for 2 hours, adding ammonium bisulfate, and continuing to stir for 0.5-1 hours to obtain the lithium-based permeate;

[0076] The mass ratio of lithium polysilicate, sodium methylsilicate, nano lithium bentonite, and ammonium bisulfate is 2:1.5:0.5:0.3.

[0077] The preparation of the modified microcrystalline cellulose includes:

[0078] Microcrystalline cellulose was added to a phenolic resin solution and stirred until homogeneous. Then, sodium alkali lignin carboxylate was added, and the mixture was stirred and reacted at 70°C for 3 hours. After filtration and drying, modified microcrystalline cellulose was obtained.

[0079] The mass ratio of microcrystalline cellulose, phenolic resin, and sodium alkali lignin carboxylate is 1:0.8:0.5.

[0080] The preparation method of the concrete surface enhancer in this embodiment is the same as that in Embodiment 1.

[0081] Example 4:

[0082] This embodiment of a concrete surface strengthening agent mainly comprises the following raw materials in the following weight ratios:

[0083] The composition consists of 20 wt% lithium-based permeate, 7 wt% silicone resin, 8 wt% epoxy resin emulsion, 4 wt% sodium sulfate, 4 wt% latex powder, 4 wt% modified microcrystalline cellulose, 4 wt% talc, 0.7 wt% film-forming aid, and 0.4 wt% defoamer, with the remainder being water.

[0084] The preparation of lithium-based penetrant and modified microcrystalline cellulose in the concrete surface enhancer of this embodiment is the same as in Example 1.

[0085] The preparation method of the concrete surface enhancer in this embodiment is the same as that in Example 1.

[0086] Example 5:

[0087] This embodiment of a concrete surface strengthening agent mainly comprises the following raw materials in the following weight ratios:

[0088] The composition consists of 25 wt% lithium-based permeate, 10 wt% silicone resin, 10 wt% epoxy resin emulsion, 5 wt% sodium sulfate, 5 wt% latex powder, 5 wt% modified microcrystalline cellulose, 5 wt% talc, 1 wt% film-forming aid, and 0.5 wt% defoamer, with the remainder being water.

[0089] The preparation of lithium-based penetrant and modified microcrystalline cellulose in the concrete surface enhancer of this embodiment is the same as in Example 1.

[0090] The preparation method of the concrete surface enhancer in this embodiment is the same as that in Example 1.

[0091] Compare with Example 1

[0092] The composition and preparation method of the concrete surface enhancer in this comparative example are the same as those in Example 1, except that a conventional lithium-based penetrant is used.

[0093] Compare with Example 2

[0094] The composition and preparation method of the concrete surface enhancer in this comparative example are the same as those in Example 1, except that modified microcrystalline cellulose was not used.

[0095] Compare with Example 3

[0096] The composition and preparation method of the concrete surface enhancer in this comparative example are the same as those in Example 1, except that unmodified microcrystalline cellulose is used.

[0097] Test case

[0098] The concrete surface enhancers prepared in Examples 1-5 and the concrete surface enhancers prepared in Comparative Examples 1-3 were applied to the concrete surface. The rebound values ​​of the concrete were measured using the rebound method according to JGJ / T23-2011 "Technical Specification for Testing the Compressive Strength of Concrete by Rebound Method". The results are shown in the table below.

[0099] Table 1

[0100] Initial rebound value 14d rebound value 28d rebound value 56d rebound value Example 1 40.5 43.1 45.7 48.8 Example 2 42.7 45.8 48.9 52.5 Example 3 44.3 47.8 51.3 54.4 Example 4 43.2 46.5 50.2 53.1 Example 5 41.8 44.2 46.8 50.2 Compare with Example 1 32.7 33.8 35.2 36.0 Compare with Example 2 35.3 37.8 40.0 42.4 Compare with Example 3 37.5 39.3 40.9 43.1

[0101] As can be seen from the results in the table, the concrete surface enhancer of the present invention increases the surface rebound rate by more than 20% after 56 days, demonstrating excellent concrete surface repair and enhancement effects.

[0102] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A concrete surface strengthening agent, characterized in that, The main raw materials include the following weight ratios: lithium-based permeate 10-25 wt%, silicone resin 3-10 wt%, epoxy resin emulsion 3-10 wt%, sodium sulfate 2-5 wt%, latex powder 2-5 wt%, modified microcrystalline cellulose 1-5 wt%, talc powder 1-5 wt%, film-forming aid 0.1-1 wt%, and defoamer 0.1-0.5 wt%, with the remainder being water; The preparation of the modified microcrystalline cellulose includes: adding microcrystalline cellulose to a phenolic resin solution and stirring until uniform, then adding sodium alkali lignin carboxylate, stirring and reacting at 50℃~70℃ for 2h~3h, filtering and drying to obtain modified microcrystalline cellulose; the mass ratio of microcrystalline cellulose, phenolic resin and sodium alkali lignin carboxylate is 1:(0.5~0.8):(0.3~0.5); The preparation of the lithium-based permeate includes: adding sodium methylsilicate and nano-lithium saponite to an aqueous solution of lithium polysilicate, and after the mixture is evenly dispersed, heating it to 50-70°C, stirring and reacting for 1-2 hours, adding ammonium bisulfate and continuing to stir for 0.5-1 hour to obtain the lithium-based permeate; wherein the mass ratio of lithium polysilicate, sodium methylsilicate, nano-lithium saponite and ammonium bisulfate is 2:(0.8-1.5):(0.1-0.5):(0.1-0.3).

2. The concrete surface strengthening agent according to claim 1, characterized in that, The main raw materials include the following weight ratios: lithium-based permeate 15-20 wt%, silicone resin 5-7 wt%, epoxy resin emulsion 5-8 wt%, sodium sulfate 3-4 wt%, latex powder 3-4 wt%, modified microcrystalline cellulose 2-4 wt%, talc powder 2-4 wt%, film-forming aid 0.3-0.7 wt%, and defoamer 0.2-0.4 wt%, with the remainder being water.

3. The concrete surface strengthening agent according to claim 2, characterized in that, The main raw materials include the following weight ratios: lithium-based permeate 17wt%, silicone resin 5.5wt%, epoxy resin emulsion 6wt%, sodium sulfate 3.5wt%, latex powder 3.5wt%, modified microcrystalline cellulose 3wt%, talc powder 2.5wt%, film-forming aid 0.5wt%, and defoamer 0.2wt%, with the remainder being water.

4. The concrete surface strengthening agent according to any one of claims 1 to 3, characterized in that, The film-forming aids include one or more of dodecyl alcohol ester, ethylene glycol butyl ether, and hexanediol butyl ether acetate.

5. The concrete surface strengthening agent according to any one of claims 1 to 3, characterized in that, The defoamer includes one or more of the following: polyoxypropylene polyoxyethylene glycerol ether, polyoxypropylene glycerol ether, polyoxyethylene ether, polyoxyethylene polyoxypropylene pentaerythritol ether, and polyoxyethylene polyoxypropylene alcohol ether.

6. A method for preparing a concrete surface strengthening agent according to any one of claims 1 to 5, characterized in that, include: Lithium-based penetrant, silicone resin, and epoxy resin emulsion are stirred and mixed evenly to obtain an initial mixture. Sodium sulfate, latex powder, modified microcrystalline cellulose, and talc are added to water and stirred evenly. Then, the mixture is added to the initial mixture while stirring and stirred evenly. Finally, film-forming aid and defoamer are added and stirring is continued for 10-20 minutes to obtain the concrete surface enhancer.

7. The application of the concrete surface enhancer according to any one of claims 1 to 5 in concrete crack repair mortar.

8. The application according to claim 7, characterized in that, The concrete surface enhancer is added to the concrete crack repair mortar at a rate of 5-10 wt%.