A repair material for concrete surface defects and preparation method thereof

Abstract

The present invention relates to the field of concrete technology, and in particular to a repair material for concrete surface defects and a preparation method thereof. The repair material for concrete surface defects comprises three components: component A, component B, and component C. Component A is composed of the following raw materials in parts by weight: 25-60 parts by weight of modified epoxy resin, 1-3 parts by weight of dispersant, 0.5-2 parts by weight of defoamer, and 5-10 parts by weight of diluent; component B is composed of the following raw materials in parts by weight: 15-30 parts by weight of curing agent, and 3-8 parts by weight of elastomer; component C is composed of the following raw materials in parts by weight: 80-150 parts by weight of cement, 120-200 parts by weight of sand, 15-30 parts by weight of densifier, 10-20 parts by weight of crystallization additive, 3-8 parts by weight of aluminum fluorosilicate, and 8-15 parts by weight of repair agent; and the repair agent is a polyurethane modified zeolite complex. The repair material of the present invention has good anti-seepage, anti-compression and anti-chloride ion properties, can repair damage, exposed reinforcement and other defects on the concrete surface, and can be used for overall repair and leveling of the concrete surface.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete, and in particular to a repairing material for concrete surface defects and a preparation method thereof. Background Art

[0002] Concrete components are widely used in various types of buildings, bridges, and roads due to their durability, strong load-bearing capacity, stability, long service life, and low construction and maintenance costs. However, due to the natural aging of concrete structures, the rapid increase in road traffic, and heavy vehicle loads, surface defects such as flaws, cracks, spalling, and honeycombing often occur due to environmental factors, loads, or poor construction quality. If these microcracks or microdamages are not repaired promptly, they not only affect the structural appearance but, if allowed to develop, are likely to develop into difficult-to-repair macrocracks, thereby reducing the durability and load-bearing capacity of the structure, affecting the service life and durability of the concrete, and even potentially leading to serious accidents such as concrete building collapse.

[0003] How to improve the repair effect of cracks and defect reinforcement has become an important issue facing the later maintenance of concrete structures. Therefore, it is of great significance to develop a concrete surface defect repair material with high bond strength, good durability and simple construction. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a repair material for concrete surface defects and a preparation method thereof.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A repair material for concrete surface defects, comprising component A, component B, and component C, wherein the weight ratio of components A, B, and C is (2-5): (1-3): (12-20); component A is composed of the following raw materials in parts by weight: 25-60 parts by weight of a modified epoxy resin, 1-3 parts by weight of a dispersant, 0.5-2 parts by weight of a defoamer, and 5-10 parts by weight of a diluent; component B is composed of the following raw materials in parts by weight: 15-30 parts by weight of a curing agent and 3-8 parts by weight of an elastomer; component C is composed of the following raw materials in parts by weight: 80-150 parts by weight of cement, 120-200 parts by weight of sand, 15-30 parts by weight of a densifier, 10-20 parts by weight of a crystallizing additive, 3-8 parts by weight of aluminum fluorosilicate, and 8-15 parts by weight of a repair agent; the repair agent is a polyurethane-modified zeolite composite; the composition of the repair material for concrete surface defects is as follows:

[0007] (i) consisting of three components: A, B and C; or

[0008] (ii) Add component C to components A and B to form a two-component mixture.

[0009] Zeolite's porous structure absorbs moisture and harmful ions (such as chloride ions), reducing the penetration of moisture and corrosive substances into concrete and improving concrete's durability. Its active substances, silica and alumina, react with calcium hydroxide, a hydration product of cement, to stimulate the formation of cementitious materials, which enhances concrete's compressive strength. Despite its numerous advantages in concrete, zeolite's relatively low mechanical properties make it difficult to use alone as a reinforcing component in high-performance repair materials. Furthermore, its weak interfacial bonding with the cementitious or polymeric matrix can lead to interfacial delamination of the repair material under stress. Polyurethane, on the other hand, exhibits high elasticity and flexibility, adapting to subtle deformations on the concrete surface and reducing cracking caused by stress concentration. It also forms a strong chemical bond with the concrete matrix, significantly improving the bond strength of the repair material. Therefore, combining zeolite with polyurethane leverages the advantages of both, compensating for zeolite's shortcomings while imparting additional functional properties to the repair material. The introduction of polyurethane not only improves the mechanical properties and interfacial compatibility of zeolite but also enhances the overall performance of the repair material through chemical bonding.

[0010] Preferably, the preparation method of the polyurethane modified zeolite composite is as follows:

[0011] S1, taking 12-20 parts by weight of zeolite powder, 0.5-2 parts by weight of graphene oxide, and 150-300 parts by weight of water, mixing and dispersing, heating and stirring to obtain a zeolite-graphene oxide composite;

[0012] S2, adding 70-150 parts by weight of N,N-dimethylformamide to 10-15 parts by weight of the above zeolite-graphene oxide composite, ultrasonically adding 2-4 parts by weight of a silane coupling agent and heating for reaction to obtain a silane-modified zeolite-graphene oxide composite;

[0013] S3. Take 3-6 parts by weight of polyol, 2-4 parts by weight of isophorone diisocyanate, and 50-100 parts by weight of dimethyl sulfoxide and heat them to obtain a polyurethane prepolymer; then add dibutyltin dilaurate, 0.5-2 parts by weight of N,N'-bis(2-hydroxyethyl)oxamide, and 10-14 parts by weight of a silane-modified zeolite-graphene oxide composite, and ultrasonically react at 70-90°C and 200-500rpm for 2-5h, and remove the solvent by distillation under reduced pressure to obtain a polyurethane-modified zeolite composite.

[0014] The specific reaction mechanism is as follows: S1. Using zeolite and graphene oxide as reaction raw materials, the oxygen-containing functional groups (such as carboxyl, hydroxyl, and epoxy) of graphene oxide react with the hydroxyl groups (-OH) on the surface of zeolite under heating and stirring conditions to form hydrogen bonds or partial covalent bonds to form a zeolite-graphene oxide composite; S2. Using zeolite-graphene oxide composite and silane coupling agent as reaction raw materials, ultrasonication causes the zeolite-graphene composite to be uniformly dispersed in N,N-dimethylformamide, exposing more surface active sites. Under heating conditions, the silane coupling agent introduces organic functional groups on the surface of the composite through hydrolysis and condensation reactions, increasing its affinity with the polymer base. The method enhances the compatibility of the polyurethane prepolymer and the stability and interfacial bonding of the composite, thereby obtaining a silane-modified zeolite-graphene oxide composite. S3. Polyol and isophorone diisocyanate are used as the main raw materials for the polyurethane reaction, dibutyltin dilaurate is used as a catalyst, and N,N'-bis(2-hydroxyethyl)oxamide is used as a chain extender. The silane-modified zeolite-graphene oxide composite is added and, under heating conditions, the -NCO end groups of the polyurethane prepolymer react with the active groups (such as amino and carboxyl groups) on the surface of the silane-modified zeolite-graphene composite to form chemical bonds (such as urea and carbamate bonds), achieving cross-linking of the composite and obtaining a polyurethane-modified zeolite composite. The preparation method of the polyurethane-modified zeolite composite achieves efficient composite formation of zeolite, graphene, and polyurethane through a multi-step reaction. The reaction mechanism of each step optimizes the interfacial bonding and functional properties of the composite. The resulting composite material has excellent comprehensive performance and is suitable for the efficient repair and reinforcement of concrete surface defects.

[0015] Furthermore, the preparation method of the polyurethane modified zeolite composite is as follows:

[0016] S1, taking 12-20 parts by weight of zeolite powder, 0.5-2 parts by weight of graphene oxide, and 150-300 parts by weight of water, mixing, ultrasonically dispersing at an ultrasonic power of 100-300 W and an ultrasonic frequency of 40-70 kHz for 0.5-2 h, stirring at 80-110 ° C and 100-400 rpm for 1.5-4 h, filtering, washing, and drying to obtain a zeolite-graphene oxide composite;

[0017] S2, add 70-150 parts by weight of N, N-dimethylformamide to 10-15 parts by weight of the above zeolite-graphene oxide composite, place it under ultrasonic power of 100-300 W and ultrasonic frequency of 40-70 kHz for 30-60 min, add 2-4 parts by weight of silane coupling agent, place it at 50-70 ° C and 400-700 rpm for 1-4 h, filter, wash, and dry to obtain a silane-modified zeolite-graphene oxide composite;

[0018] S3. Take 3-6 parts by weight of polyol, 2-4 parts by weight of isophorone diisocyanate, and 50-100 parts by weight of dimethyl sulfoxide, react at 70-90°C and 300-500rpm for 1-3h to obtain a polyurethane prepolymer; then add 0.05-0.3 parts by weight of dibutyltin dilaurate, 0.5-2 parts by weight of N,N'-bis(2-hydroxyethyl)oxamide, and 10-14 parts by weight of a silane-modified zeolite-graphene oxide composite, place it in an ultrasonic power of 100-300W and an ultrasonic frequency of 40-70 for ultrasonic dispersion for 1-3h, react at 70-90°C and 200-500rpm for 2-5h, and remove the solvent by distillation under reduced pressure to obtain a polyurethane-modified zeolite composite.

[0019] The surface of the polyurethane modified zeolite composite prepared by the present invention has multiple functional groups, combining the three effects of zeolite, graphene oxide and polyurethane. Zeolite has good adsorption capacity and can effectively adsorb a variety of harmful heavy metal ions in concrete. The microporous structure and ion exchange capacity of zeolite can adsorb and neutralize acid and alkali substances. At the same time, zeolite also has density and can fill micro cracks and pores on the surface of concrete. It can replace part of cement, effectively reduce the amount of cement, and improve the density and mechanical properties of the material. The high specific surface area and excellent mechanical properties of graphene oxide can significantly improve the tensile strength and crack resistance of the repair material, and can form strong chemical bonds with the cement matrix and polymer to enhance the interfacial adhesion. Its layered structure can form a dense The barrier layer reduces the penetration of moisture and harmful ions. Graphene oxide and silane coupling agent enhance the hydrophobicity and interfacial bonding force of zeolite, reduce medium penetration, and improve the shrinkage resistance of the repair material. The polyurethane material has good mechanical properties, good compressive resistance, and good bonding properties. It can form a strong chemical bond with the concrete matrix, significantly improving the bonding strength between the repair material and the matrix. After the introduction of polyurethane, the flexibility of the repair material can be improved, enabling it to adapt to the slight deformation of the concrete surface, reducing cracking caused by stress concentration, and further forming a corrosion-resistant organic-inorganic hybrid network to block the acid and alkali erosion path.

[0020] Zeolite and graphene oxide are modified with polyurethane, and the three are combined to produce a synergistic reinforcement effect. Zeolite makes the concrete structure denser, graphene oxide improves the shrinkage resistance of concrete while also increasing the mechanical properties and durability of concrete. The composite of polyurethane and zeolite can fill the microcracks and pores on the surface of concrete, improving the density, compressive strength and impermeability of the repair material.

[0021] Preferably, the silane coupling agent is at least one of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and N-[β-(N,N-diacetyl)aminoethyl]-γ-(N-acetyl)aminopropyltrimethoxysilane; preferably, the silane coupling agent is a mixture of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and N-[β-(N,N-diacetyl)aminoethyl]-γ-(N-acetyl)aminopropyltrimethoxysilane in a mass ratio of 1:(1-3).

[0022] This application uses a mixture of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and N-[β-(N,N-diacetoxy)aminoethyl]-γ-(N-acetoxy)aminopropyltrimethoxysilane in a mass ratio of 1:2. The possible reason is that 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane contains two amino groups, which have high reactivity and can react with the isocyanate group (-NCO) in the polyurethane prepolymer to enhance the crosslinking strength and mechanical properties of the composite; N-[β-(N,N-diacetoxy)aminoethyl]-γ-(N-acetoxy)aminopropyltrimethoxysilane contains multiple acetic acid groups (-COO⁻), which can adsorb harmful ions in concrete through ion exchange, thereby improving the shrinkage resistance and durability of the repair material. This synergistic effect gives the repair material excellent mechanical properties, interfacial bonding strength, shrinkage resistance, and durability, making it suitable for the efficient repair and reinforcement of concrete surface defects.

[0023] Preferably, the polyol is any one of polycaprolactone triol, polytetramethylene ether glycol, polyethylene glycol, and polypropylene glycol.

[0024] Preferably, the dispersant in component A is any one of sodium dodecylbenzenesulfonate, octylphenol polyoxyethylene ether, and fatty acid monoethanolamide; the defoamer is any one of silicone defoamer and polyether defoamer; and the diluent is any one of propylene oxide butyl ether, propylene oxide phenyl ether, and polyglycidyl ether.

[0025] Preferably, the curing agent in the B component is any one of an aliphatic polyamine curing agent, an acid anhydride curing agent, and an aromatic amine curing agent; the elastomer is any one of an ethylene-propylene copolymer, a styrene-ethylene-butylene-styrene copolymer, chloroprene rubber, natural rubber, styrene-butadiene rubber, and EPDM rubber.

[0026] Preferably, the crystallization additive in the C component is at least one of calcium oxide, magnesium oxide, and aluminum oxide; the densifier is at least one of lanthanum oxide, calcium phosphate, dihydrate calcium hydrogen phosphate, and cerium oxide. Rare earth oxides have excellent chemical stability and can react with acid and alkaline media to form an inert protective layer to slow down corrosion. The addition of rare earth oxides is beneficial to improving the mortar's resistance to chloride ion penetration. In particular, when lanthanum oxide is added alone, the effect of improving the resistance to chloride ion penetration is the best, which can fill pores and inhibit harmful ions (such as Cl⁻, SO4 2- ) penetration, lanthanum oxide and zeolite complex improves acid and alkali resistance through the dual effects of physical barrier and chemical stability.

[0027] The method for preparing the repair material for concrete surface defects comprises the following steps:

[0028] (1) Preparation of component A: Weigh the raw materials according to the ratio of each raw material, add them into the blender in sequence, stir at 300-500 rpm for 15-30 minutes to obtain component A, and package and store;

[0029] (2) Preparation of component B: Weigh the raw materials according to the ratio of each raw material, add them into the blender in sequence, stir at 300-500 rpm for 5-20 minutes to obtain component B, and package and store;

[0030] (3) Preparation of component C: Weigh the raw materials according to the ratio of each raw material, add them into the blender in sequence, stir at 300-500 rpm for 5-20 min to obtain component C, and package and store;

[0031] (4) Weigh each component according to the mass ratio of component A, component B, and component C. First, mix component A with component B and stir evenly. Finally, add component C and stir evenly to obtain the repair material for concrete surface defects.

[0032] Beneficial effects of the present invention: 1. The present invention provides a repair material for concrete surface defects and a preparation method thereof. By using a polyurethane-modified zeolite composite, the respective advantages of zeolite, graphene oxide and polyurethane are combined. When applied to the repair of concrete surface defects, the anti-penetration performance of the repair material can be improved, and cracking, hollowing and falling-off can be effectively avoided. At the same time, it also has good compressive resistance and chloride ion resistance, which significantly improves the comprehensive performance of the repair material and realizes the multifunctionality and high performance of the repair material.

[0033] 2. Compared with ordinary concrete repair materials, the repair material prepared by the present invention utilizes the mutual synergistic effect between the raw materials, improves the gap filling performance and mechanical strength of the repair material for concrete surface defects, thereby improving the repair effect of concrete surface defects and reinforcing them, and prolongs the service life of concrete pavements. The repair material can be widely used in crack repair, surface reinforcement, spalling, hole and wear defect repair of concrete structures, and is particularly suitable for occasions with high durability requirements such as bridges, tunnels, and engineering buildings.

[0034] 3. Compared with the current traditional concrete repair materials, the product provided by the present invention has excellent elastic deformation ability and maintains excellent bonding performance with concrete structures. Especially when used in combination with nano-gelatin materials, it can give full play to the excellent adaptability of the two materials. DETAILED DESCRIPTION

[0035] The above content of the present invention will be further described in detail below in conjunction with specific embodiments, but it should not be understood that the scope of the above subject matter of the present invention is limited to the following embodiments.

[0036] Some of the raw materials described in this application are commercially available:

[0037] The modified epoxy resin was purchased from Langfang Xinhaochang Anticorrosion Materials Co., Ltd., model 109-92-2.

[0038] The organosilicon defoamer was purchased from Shandong Wanhua Tianhe New Materials Co., Ltd., model: th-5600.

[0039] Styrene-ethylene-butylene-styrene copolymer was purchased from Dongguan Shengli New Materials Co., Ltd., Cat. No.

[0040] HH1160ZYOONN.

[0041] The cement was purchased from Conch (Hefei) Holdings Co., Ltd., with a compressive strength of more than 50 MPa.

[0042] The sand was purchased from Shanghai Jiyun Building Materials Co., Ltd., with a mud content of 0.1%, and the model is river sand.

[0043] Zeolite powder was purchased from Zhengzhou Chaorong Nanomaterial Co., Ltd., model CR-1273, mesh size: 325 mesh.

[0044] Graphene oxide was purchased from Shenzhen Liyou New Energy Technology Co., Ltd., model TOB-Graphene-510.

[0045] Polycaprolactone triol was purchased from Hubei Darli Chemical Co., Ltd., model Darl-1.

[0046] Example 1: A repair material for concrete surface defects, consisting of component A, component B, and component C, wherein the weight ratio of component A, component B, and component C is 3:2:15, and the component A is composed of the following raw materials in parts by weight: 40 parts by weight of modified epoxy resin, 2 parts by weight of sodium dodecylbenzenesulfonate, 1 part by weight of silicone defoamer TH-5600, and 8 parts by weight of propylene oxide phenyl ether; the component B is composed of the following raw materials in parts by weight: 20 parts by weight of tetraethylene pentamine and 4 parts by weight of styrene-ethylene-butylene-styrene copolymer; the component C is composed of the following raw materials in parts by weight: 100 parts by weight of cement, 150 parts by weight of sand, 20 parts by weight of lanthanum oxide, 15 parts by weight of calcium oxide, 5 parts by weight of aluminum fluorosilicate, and 10 parts by weight of repair agent.

[0047] The repairing agent is zeolite powder.

[0048] The method for preparing the repair material for concrete surface defects comprises the following steps:

[0049] (1) Preparation of component A: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 20 minutes to obtain component A. Package and store.

[0050] (2) Preparation of component B: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 minutes to obtain component B, which is then packaged and stored.

[0051] (3) Preparation of component C: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 min to obtain component C, which is then packaged and stored.

[0052] (4) Weigh each component according to the mass ratio of component A, component B, and component C. First, mix component A with component B and stir evenly. Finally, add component C and stir evenly to obtain the repair material for concrete surface defects.

[0053] Example 2: A repair material for concrete surface defects, consisting of component A, component B, and component C, wherein the weight ratio of component A, component B, and component C is 2:1:12, and the component A is composed of the following raw materials in parts by weight: 40 parts by weight of modified epoxy resin, 2 parts by weight of sodium dodecylbenzenesulfonate, 1 part by weight of silicone defoamer TH-5600, and 8 parts by weight of propylene oxide phenyl ether; the component B is composed of the following raw materials in parts by weight: 20 parts by weight of tetraethylene pentamine and 4 parts by weight of styrene-ethylene-butylene-styrene copolymer; the component C is composed of the following raw materials in parts by weight: 100 parts by weight of cement, 150 parts by weight of sand, 20 parts by weight of lanthanum oxide, 15 parts by weight of calcium oxide, 5 parts by weight of aluminum fluorosilicate, and 10 parts by weight of repair agent.

[0054] The repair agent is a zeolite-graphene oxide composite. The preparation method of the zeolite composite is as follows: 16 parts by weight of zeolite powder, 1 part by weight of graphene oxide, and 200 parts by weight of water are mixed, ultrasonically dispersed at an ultrasonic power of 200 W and an ultrasonic frequency of 60 kHz for 1 hour, stirred at 100°C and 200 rpm for 2.5 hours, filtered, washed, and dried to obtain a zeolite-graphene oxide composite.

[0055] The method for preparing the repair material for concrete surface defects comprises the following steps:

[0056] (1) Preparation of component A: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 20 minutes to obtain component A. Package and store.

[0057] (2) Preparation of component B: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 minutes to obtain component B, which is then packaged and stored.

[0058] (3) Preparation of component C: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 min to obtain component C, which is then packaged and stored.

[0059] (4) Weigh each component according to the mass ratio of component A, component B, and component C. First, mix component A with component B and stir evenly. Finally, add component C and stir evenly to obtain the repair material for concrete surface defects.

[0060] Example 3: A repair material for concrete surface defects, consisting of component A, component B, and component C, wherein the weight ratio of component A, component B, and component C is 5:3:20, and the component A is composed of the following raw materials in parts by weight: 40 parts by weight of modified epoxy resin, 2 parts by weight of sodium dodecylbenzenesulfonate, 1 part by weight of silicone defoamer TH-5600, and 8 parts by weight of propylene oxide phenyl ether; the component B is composed of the following raw materials in parts by weight: 20 parts by weight of tetraethylene pentamine and 4 parts by weight of styrene-ethylene-butylene-styrene copolymer; the component C is composed of the following raw materials in parts by weight: 100 parts by weight of cement, 150 parts by weight of sand, 20 parts by weight of lanthanum oxide, 15 parts by weight of calcium oxide, 5 parts by weight of aluminum fluorosilicate, and 10 parts by weight of repair agent.

[0061] The repair agent is a modified zeolite composite, and the preparation method of the modified zeolite composite is as follows:

[0062] S1, taking 16 parts by weight of zeolite powder, 1 part by weight of graphene oxide, and 200 parts by weight of water, mixing, ultrasonically dispersing at an ultrasonic power of 200 W and an ultrasonic frequency of 60 kHz for 1 hour, stirring at 100° C. and 200 rpm for 2.5 hours, filtering, washing, and drying to obtain a zeolite-graphene oxide composite;

[0063] S2. Add 100 parts by weight of N,N-dimethylformamide to 12 parts by weight of the above-mentioned zeolite-graphene oxide composite, place it under ultrasonic power of 200 W and ultrasonic frequency of 60 kHz for 40 minutes, add 3 parts by weight of silane coupling agent, place it at 60 ° C and 600 rpm to react for 2 hours, filter, wash, and dry to obtain a silane-modified zeolite-graphene oxide composite; the silane coupling agent is N-[β-(N,N-diacetyl)aminoethyl]-γ-(N-acetyl)aminopropyltrimethoxysilane.

[0064] The method for preparing the repair material for concrete surface defects comprises the following steps:

[0065] (1) Preparation of component A: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 20 minutes to obtain component A. Package and store.

[0066] (2) Preparation of component B: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 minutes to obtain component B, which is then packaged and stored.

[0067] (3) Preparation of component C: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 min to obtain component C, which is then packaged and stored.

[0068] (4) Weigh each component according to the mass ratio of component A, component B, and component C. First, mix component A with component B and stir evenly. Finally, add component C and stir evenly to obtain the repair material for concrete surface defects.

[0069] Example 4: A repair material for concrete surface defects, consisting of component A, component B, and component C, wherein the weight ratio of component A, component B, and component C is 4:1:18, and the component A is composed of the following raw materials in parts by weight: 40 parts by weight of modified epoxy resin, 2 parts by weight of sodium dodecylbenzenesulfonate, 1 part by weight of silicone defoamer TH-5600, and 8 parts by weight of propylene oxide phenyl ether; the component B is composed of the following raw materials in parts by weight: 20 parts by weight of tetraethylene pentamine and 4 parts by weight of styrene-ethylene-butylene-styrene copolymer; the component C is composed of the following raw materials in parts by weight: 100 parts by weight of cement, 150 parts by weight of sand, 20 parts by weight of lanthanum oxide, 15 parts by weight of calcium oxide, 5 parts by weight of aluminum fluorosilicate, and 10 parts by weight of repair agent.

[0070] The repair agent is a polyurethane-modified zeolite composite, and the preparation method of the polyurethane-modified zeolite composite is as follows:

[0071] S1, taking 16 parts by weight of zeolite powder, 1 part by weight of graphene oxide, and 200 parts by weight of water, mixing, ultrasonically dispersing at an ultrasonic power of 200 W and an ultrasonic frequency of 60 kHz for 1 hour, stirring at 100° C. and 200 rpm for 2.5 hours, filtering, washing, and drying to obtain a zeolite-graphene oxide composite;

[0072] S2. Add 100 parts by weight of N,N-dimethylformamide to 12 parts by weight of the above-mentioned zeolite-graphene oxide composite, place it under ultrasonic power of 200 W and ultrasonic frequency of 60 kHz for 40 min, add 3 parts by weight of silane coupling agent, place it at 60 ° C and 600 rpm for 2 h, filter, wash and dry to obtain a silane-modified zeolite-graphene oxide composite; the silane coupling agent is N-[β-(N,N-diacetoxy)aminoethyl]-γ-(N-acetoxy)aminopropyltrimethoxysilane;

[0073] S3. Take 4 parts by weight of polycaprolactone triol, 3 parts by weight of isophorone diisocyanate, and 60 parts by weight of dimethyl sulfoxide, and react at 80°C and 400 rpm for 1.5 hours to obtain a polyurethane prepolymer; then add 0.1 parts by weight of dibutyltin dilaurate, 1 part by weight of N,N'-bis(2-hydroxyethyl)oxamide, and 12 parts by weight of a silane-modified zeolite-graphene oxide composite, and ultrasonically disperse the mixture at an ultrasonic power of 200 W and an ultrasonic frequency of 60 kHz for 2 hours, react at 80°C and 400 rpm for 3 hours, and remove the solvent by distillation under reduced pressure to obtain a polyurethane-modified zeolite composite.

[0074] The method for preparing the repair material for concrete surface defects comprises the following steps:

[0075] (1) Preparation of component A: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 20 minutes to obtain component A. Package and store.

[0076] (2) Preparation of component B: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 minutes to obtain component B, which is then packaged and stored.

[0077] (3) Preparation of component C: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 min to obtain component C, which is then packaged and stored.

[0078] (4) Weigh each component according to the mass ratio of component A, component B, and component C. First, mix component A with component B and stir evenly. Finally, add component C and stir evenly to obtain the repair material for concrete surface defects.

[0079] Example 5: A repair material for concrete surface defects, consisting of component A, component B, and component C, wherein the weight ratio of component A, component B, and component C is 2:3:14, and the component A is composed of the following raw materials in parts by weight: 40 parts by weight of modified epoxy resin, 2 parts by weight of sodium dodecylbenzenesulfonate, 1 part by weight of silicone defoamer TH-5600, and 8 parts by weight of propylene oxide phenyl ether; the component B is composed of the following raw materials in parts by weight: 20 parts by weight of tetraethylene pentamine and 4 parts by weight of styrene-ethylene-butylene-styrene copolymer; the component C is composed of the following raw materials in parts by weight: 100 parts by weight of cement, 150 parts by weight of sand, 20 parts by weight of lanthanum oxide, 15 parts by weight of calcium oxide, 5 parts by weight of aluminum fluorosilicate, and 10 parts by weight of repair agent.

[0080] The repair agent is a polyurethane-modified zeolite composite, and the preparation method of the polyurethane-modified zeolite composite is as follows:

[0081] S1, taking 16 parts by weight of zeolite powder, 1 part by weight of graphene oxide, and 200 parts by weight of water, mixing, ultrasonically dispersing at an ultrasonic power of 200 W and an ultrasonic frequency of 60 kHz for 1 hour, stirring at 100° C. and 200 rpm for 2.5 hours, filtering, washing, and drying to obtain a zeolite-graphene oxide composite;

[0082] S2. Take 4 parts by weight of polycaprolactone triol, 3 parts by weight of isophorone diisocyanate, and 60 parts by weight of dimethyl sulfoxide, and react at 80°C and 400 rpm for 1.5 hours to obtain a polyurethane prepolymer; then add 0.1 parts by weight of dibutyltin dilaurate, 1 part by weight of N,N'-bis(2-hydroxyethyl)oxamide, and 12 parts by weight of zeolite-graphene oxide composite, and ultrasonically disperse for 2 hours at an ultrasonic power of 200 W and an ultrasonic frequency of 60 kHz, react at 80°C and 400 rpm for 3 hours, and remove the solvent by distillation under reduced pressure to obtain a polyurethane modified zeolite composite.

[0083] The method for preparing the repair material for concrete surface defects comprises the following steps:

[0084] (1) Preparation of component A: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 20 minutes to obtain component A. Package and store.

[0085] (2) Preparation of component B: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 minutes to obtain component B, which is then packaged and stored.

[0086] (3) Preparation of component C: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 min to obtain component C, which is then packaged and stored.

[0087] (4) Weigh each component according to the mass ratio of component A, component B, and component C. First, mix component A with component B and stir evenly. Finally, add component C and stir evenly to obtain the repair material for concrete surface defects.

[0088] Example 6: A repair material for concrete surface defects, consisting of component A, component B, and component C, wherein the weight ratio of component A, component B, and component C is 5:3:16, and the component A is composed of the following raw materials in parts by weight: 40 parts by weight of modified epoxy resin, 2 parts by weight of sodium dodecylbenzenesulfonate, 1 part by weight of silicone defoamer TH-5600, and 8 parts by weight of propylene oxide phenyl ether; the component B is composed of the following raw materials in parts by weight: 20 parts by weight of tetraethylene pentamine and 4 parts by weight of styrene-ethylene-butylene-styrene copolymer; the component C is composed of the following raw materials in parts by weight: 100 parts by weight of cement, 150 parts by weight of sand, 20 parts by weight of lanthanum oxide, 15 parts by weight of calcium oxide, 5 parts by weight of aluminum fluorosilicate, and 10 parts by weight of repair agent.

[0089] The repair agent is a polyurethane-modified zeolite composite, and the preparation method of the polyurethane-modified zeolite composite is as follows:

[0090] S1, taking 16 parts by weight of zeolite powder, 1 part by weight of graphene oxide, and 200 parts by weight of water, mixing, ultrasonically dispersing at an ultrasonic power of 200 W and an ultrasonic frequency of 60 kHz for 1 hour, stirring at 100° C. and 200 rpm for 2.5 hours, filtering, washing, and drying to obtain a zeolite-graphene oxide composite;

[0091] S2. Add 100 parts by weight of N,N-dimethylformamide to 12 parts by weight of the above-mentioned zeolite-graphene oxide composite, place it under ultrasonic power of 200 W and ultrasonic frequency of 60 kHz for 40 min, add 3 parts by weight of silane coupling agent, place it at 60° C. and 600 rpm for 2 h, filter, wash, and dry to obtain a silane-modified zeolite-graphene oxide composite; the silane coupling agent is 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane;

[0092] S3. Take 4 parts by weight of polycaprolactone triol, 3 parts by weight of isophorone diisocyanate, and 60 parts by weight of dimethyl sulfoxide, and react at 80°C and 400 rpm for 1.5 hours to obtain a polyurethane prepolymer; then add 0.1 parts by weight of dibutyltin dilaurate, 1 part by weight of N,N'-bis(2-hydroxyethyl)oxamide, and 12 parts by weight of a silane-modified zeolite-graphene oxide composite, and ultrasonically disperse the mixture at an ultrasonic power of 200 W and an ultrasonic frequency of 60 kHz for 2 hours, react at 80°C and 400 rpm for 3 hours, and remove the solvent by distillation under reduced pressure to obtain a polyurethane-modified zeolite composite.

[0093] The method for preparing the repair material for concrete surface defects comprises the following steps:

[0094] (1) Preparation of component A: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 20 minutes to obtain component A. Package and store.

[0095] (2) Preparation of component B: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 minutes to obtain component B, which is then packaged and stored.

[0096] (3) Preparation of component C: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 min to obtain component C, which is then packaged and stored.

[0097] (4) Weigh each component according to the mass ratio of component A, component B, and component C. First, mix component A with component B and stir evenly. Finally, add component C and stir evenly to obtain the repair material for concrete surface defects.

[0098] Example 7: A repair material for concrete surface defects, consisting of component A, component B, and component C, wherein the weight ratio of component A, component B, and component C is 3:1:15, and the component A is composed of the following raw materials in parts by weight: 40 parts by weight of modified epoxy resin, 2 parts by weight of sodium dodecylbenzenesulfonate, 1 part by weight of silicone defoamer TH-5600, and 8 parts by weight of propylene oxide phenyl ether; the component B is composed of the following raw materials in parts by weight: 20 parts by weight of tetraethylene pentamine and 4 parts by weight of styrene-ethylene-butylene-styrene copolymer; the component C is composed of the following raw materials in parts by weight: 100 parts by weight of cement, 150 parts by weight of sand, 20 parts by weight of lanthanum oxide, 15 parts by weight of calcium oxide, 5 parts by weight of aluminum fluorosilicate, and 10 parts by weight of repair agent.

[0099] The repair agent is a polyurethane-modified zeolite composite, and the preparation method of the polyurethane-modified zeolite composite is as follows:

[0100] S1, taking 16 parts by weight of zeolite powder, 1 part by weight of graphene oxide, and 200 parts by weight of water, mixing, ultrasonically dispersing at an ultrasonic power of 200 W and an ultrasonic frequency of 60 kHz for 1 hour, stirring at 100° C. and 200 rpm for 2.5 hours, filtering, washing, and drying to obtain a zeolite-graphene oxide composite;

[0101] S2. Add 100 parts by weight of N, N-dimethylformamide to 12 parts by weight of the above-mentioned zeolite-graphene oxide composite, place it under ultrasonic power 200 W and ultrasonic frequency 60 kHz for 40 min, add 3 parts by weight of silane coupling agent, place it at 60 ° C and 600 rpm for reaction 2 h, filter, wash and dry to obtain a silane-modified zeolite-graphene oxide composite; the silane coupling agent is a mixture of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and N-[β-(N,N-diacetyl)aminoethyl]-γ-(N-acetyl)aminopropyltrimethoxysilane in a mass ratio of 1:2;

[0102] S3. Take 4 parts by weight of polycaprolactone triol, 3 parts by weight of isophorone diisocyanate, and 60 parts by weight of dimethyl sulfoxide, and react at 80°C and 400 rpm for 1.5 hours to obtain a polyurethane prepolymer; then add 0.1 parts by weight of dibutyltin dilaurate, 1 part by weight of N,N'-bis(2-hydroxyethyl)oxamide, and 12 parts by weight of a silane-modified zeolite-graphene oxide composite, and ultrasonically disperse the mixture at an ultrasonic power of 200 W and an ultrasonic frequency of 60 kHz for 2 hours, react at 80°C and 400 rpm for 3 hours, and remove the solvent by distillation under reduced pressure to obtain a polyurethane-modified zeolite composite.

[0103] The method for preparing the repair material for concrete surface defects comprises the following steps:

[0104] (1) Preparation of component A: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 20 minutes to obtain component A. Package and store.

[0105] (2) Preparation of component B: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 minutes to obtain component B, which is then packaged and stored.

[0106] (3) Preparation of component C: Weigh the raw materials according to the ratio of each raw material and add them into the blender in sequence. Stir at 400 rpm for 10 min to obtain component C, which is then packaged and stored.

[0107] (4) Weigh each component according to the mass ratio of component A, component B, and component C. First, mix component A with component B and stir evenly. Finally, add component C and stir evenly to obtain the repair material for concrete surface defects.

[0108] Test Example 1: Basic performance test: The test was carried out with reference to JGJ / T70-2009 "Standard for Test Methods for Basic Performance of Building Mortar". The repair materials for concrete surface defects of Examples 1-7 were transported to the laboratory 24 hours in advance, placed at 20°C, and stirred for 5 minutes using a mortar mixer to form prismatic specimens with a size of 40 mm × 40 mm × 160 mm, and a cavity with a diameter of 6.5 mm was opened at each end of the specimen. The test specimens were cured for 24 hours at 20°C and a relative humidity of 60%, and then demolded. They were placed in standard water and cured for 28 days before mechanical performance testing was performed. The impermeability and compressive properties were tested. Three groups of parallel samples were tested, and the average value was taken. The results are shown in Table 1.

[0109] Table 1 Anti-seepage pressure test results

[0110]

[0111] Test Example 2: Basic performance test: The test was conducted with reference to JGJ / T70-2009 "Standard for Test Methods for Basic Performance of Building Mortar". The concrete structure specimens in Test Example 1 were subjected to compressive strength tests after curing for 28 days. Three groups of parallel samples were tested and the average value was taken. The results are shown in Table 2.

[0112] Table 2 Basic performance test results

[0113]

[0114] Test Example 3: Chloride ion penetration resistance test: The test was conducted according to the method described in Chapter 3 of “Study on Chloride Ion and Carbonation Resistance of Graphene Oxide Regenerated Concrete” (Miao Hang, Shenyang Jianzhu University, Master’s Thesis). Each group of samples was tested 4 times, and the average value was taken. The results are shown in Table 3.

[0115] Table 3 Test results of chloride ion penetration resistance

[0116]

[0117] From the above results, it can be seen that the repair material for concrete surface defects prepared by the present invention is used in concrete repair, has good repair performance on the concrete surface, and can be used for local repair and overall coating repair of concrete. The product of the present invention has good anti-penetration performance and can effectively repair concrete cracking, hollowing and falling off. At the same time, it also has good compressive strength, elastic elongation and chloride ion resistance. Comparing Examples 1-3, it can be seen that the high specific surface area and excellent mechanical properties of graphene oxide can significantly improve the tensile strength and crack resistance of the repair material, and can form strong chemical bonds with the cement matrix and polymer to enhance the interfacial adhesion; its lamellar structure can form a dense barrier layer, reduce the penetration of moisture and harmful ions, and improve the shrinkage resistance of the repair material; Comparing Examples 4-5, it can be seen that zeolite and graphene oxide are modified by polyurethane, and the three are combined to produce a synergistic reinforcement effect. Zeolite makes the concrete structure denser, graphene oxide improves the shrinkage resistance of concrete while also increasing the mechanical properties and durability of concrete. The composite of polyurethane and zeolite can fill the microcracks and pores on the concrete surface, thereby improving the density, compressive strength and impermeability of the repair material. Finally, by comparing Example 4 with Examples 6-7, it can be seen that the present invention adopts a mixture of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and N-[β-(N,N-diacetyl)aminoethyl]-γ-(N-acetyl)aminopropyltrimethoxysilane in a mass ratio of 1:2. The possible reason is that 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane contains two amino groups, which have high reactivity and can react with the isocyanate group (-NCO) in the polyurethane prepolymer to enhance the crosslinking strength and mechanical properties of the composite; N-[β-(N,N-diacetyl)aminoethyl]-γ-(N-acetyl)aminopropyltrimethoxysilane contains multiple acetic acid groups (-COO⁻), which can adsorb harmful ions in concrete through ion exchange, thereby improving the shrinkage resistance and durability of the repair material. This synergistic effect gives the repair material excellent mechanical properties, interfacial bonding, shrinkage resistance and durability, and is suitable for efficient repair and reinforcement of concrete surface defects. As can be seen from Table 3 above, the repair material for concrete surface defects prepared by the present invention has good resistance to chloride ion penetration. The reason is that rare earth oxides have excellent chemical stability and can react with acid and alkaline media to form an inert protective layer to slow down corrosion. The addition of rare earth oxides is beneficial to improving the mortar's resistance to chloride ion penetration. In particular, when lanthanum oxide is added alone, the effect of improving the resistance to chloride ion penetration is the best. It can fill pores and inhibit the penetration of harmful ions Cl⁻. The lanthanum oxide and zeolite complex improves acid and alkali resistance through the dual effects of physical barrier and chemical stability, can effectively prevent acid and alkaline water, and effectively prevent external chlorides from entering the concrete.

[0118] In summary, the polyurethane-modified zeolite composite prepared by the present invention has a variety of functional groups on its surface, combining the three effects of zeolite, graphene oxide and polyurethane. Zeolite has good adsorption capacity and can effectively adsorb a variety of harmful heavy metal ions in concrete; at the same time, zeolite also has density, can fill the microcracks and pores on the surface of concrete, can replace part of the cement, effectively reduce the amount of cement, and improve the density and mechanical properties of the material; the high specific surface area and excellent mechanical properties of graphene oxide can significantly improve the tensile strength and crack resistance of the repair material, and can form strong chemical bonds with the cement matrix and polymer to enhance the interfacial adhesion; its lamellar structure can form a dense barrier layer, reduce the penetration of moisture and harmful ions, improve the shrinkage resistance of the repair material, and effectively improve the acid and alkali resistance of the repair material; polyurethane material has good mechanical properties, good compressive resistance, and good bonding properties. It can form a strong chemical bond with the concrete matrix, significantly improving the bonding strength between the repair material and the matrix. After the introduction of polyurethane, the flexibility of the repair material can be improved, so that it can adapt to the slight deformation of the concrete surface and reduce cracking caused by stress concentration.

[0119] The concrete surface defect repair material provided by this invention can not only repair concrete damage, exposed rebar, and voids, but can also be used for overall concrete surface repair and coating. Its application areas include, but are not limited to: surface spalling repair and pits caused by partial loss of surface mortar or concrete; honeycomb holes: loose, porous structures caused by incomplete vibration or trapped bubbles; wear and sanding: exposed aggregate and powdered mortar layers caused by mechanical friction or weathering; exposed aggregate defects: rough surfaces caused by missing surface cement slurry and exposed coarse aggregate; and bridge structures: concrete repairs on the inside and outside of slab beams, box beams, and crash barriers.

Claims

1. A repair material for concrete surface defects, characterized in that: The invention comprises component A, component B and component C, wherein component A is composed of the following raw materials in parts by weight: 25-60 parts by weight of modified epoxy resin, 1-3 parts by weight of dispersant, 0.5-2 parts by weight of defoamer and 5-10 parts by weight of diluent; component B is composed of the following raw materials in parts by weight: 15-30 parts by weight of curing agent and 3-8 parts by weight of elastomer; component C is composed of the following raw materials in parts by weight: 80-150 parts by weight of cement, 120-200 parts by weight of sand, 15-30 parts by weight of densifier, 10-20 parts by weight of crystallization additive, 3-8 parts by weight of aluminum fluorosilicate and 8-15 parts by weight of repair agent; the repair agent is a polyurethane modified zeolite composite; the composition of the repair material for concrete surface defects is as follows: (i) consisting of three components: A, B and C; or (ii) adding component C to components A and B to form a two-component mixture; The preparation method of the polyurethane modified zeolite composite is as follows: S1, taking 12-20 parts by weight of zeolite powder, 0.5-2 parts by weight of graphene oxide, and 150-300 parts by weight of water, mixing and dispersing, and stirring at 80-110° C. and 100-400 rpm for 1.5-4 hours to obtain a zeolite-graphene oxide composite; S2. Add 70-150 parts by weight of N,N-dimethylformamide to 10-15 parts by weight of the zeolite-graphene oxide composite, ultrasonically add 2-4 parts by weight of a silane coupling agent, and react at 50-70° C. and 400-700 rpm for 1-4 hours to obtain a silane-modified zeolite-graphene oxide composite; S3. Take 3-6 parts by weight of polyol, 2-4 parts by weight of isophorone diisocyanate, and 50-100 parts by weight of dimethyl sulfoxide, and react at 70-90°C and 300-500rpm for 1-3h to obtain a polyurethane prepolymer; then add dibutyltin dilaurate, 0.5-2 parts by weight of N,N'-bis(2-hydroxyethyl)oxamide, and 10-14 parts by weight of a silane-modified zeolite-graphene oxide composite, and ultrasonically react at 70-90°C and 200-500rpm for 2-5h. Remove the solvent by distillation under reduced pressure to obtain a polyurethane-modified zeolite composite.

2. The repair material for concrete surface defects according to claim 1, characterized in that: The silane coupling agent is at least one of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and N-[β-(N,N-diacetyl)aminoethyl]-γ-(N-acetyl)aminopropyltrimethoxysilane.

3. The repair material for concrete surface defects according to claim 1, characterized in that: The polyol is any one of polycaprolactone triol, polytetramethylene ether glycol, polyethylene glycol and polypropylene glycol.

4. The repair material for concrete surface defects according to claim 1, characterized in that: The dispersant in component A is any one of sodium dodecylbenzenesulfonate, octylphenol polyoxyethylene ether, and fatty acid monoethanolamide; the defoaming agent is any one of silicone defoaming agent and polyether defoaming agent; and the diluent is any one of propylene oxide butyl ether, propylene oxide phenyl ether, and polyglycidyl ether.

5. The repairing material for concrete surface defects according to claim 1, characterized in that: The curing agent in the B component is any one of an aliphatic polyamine curing agent, an acid anhydride curing agent, and an aromatic amine curing agent; the elastomer is any one of an ethylene-propylene copolymer, a styrene-ethylene-butylene-styrene copolymer, chloroprene rubber, natural rubber, styrene-butadiene rubber, and EPDM rubber.

6. The repairing material for concrete surface defects according to claim 1, characterized in that: The crystallization additive in the C component is at least one of calcium oxide, magnesium oxide, and aluminum oxide; the densifying agent is at least one of lanthanum oxide, calcium phosphate, calcium hydrogen phosphate dihydrate, and cerium oxide.

7. The repairing material for concrete surface defects according to claim 1, characterized in that: The weight ratio of component A, component B and component C is (2-5):1:(12-20).

8. The method for preparing the repairing material for concrete surface defects according to any one of claims 1 to 7, characterized in that: The steps include: (1) Preparation of component A: Weigh the raw materials according to the ratio of each raw material, add them into the blender in sequence, stir them evenly to obtain component A, and package and store; (2) Preparation of component B: weigh the raw materials according to the ratio of each raw material, add them into the blender in sequence, stir them evenly to obtain component B, and package and store them; (3) Preparation of component C: weigh the raw materials according to the ratio of each raw material, add them into the blender in sequence, stir them evenly to obtain component C, and package and store them; (4) Weigh each component according to the mass ratio of component A, component B, and component C. First, mix component A with component B and stir evenly. Finally, add component C and stir evenly to obtain the repair material for concrete surface defects.

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