A method for repairing the wet interface of marine concrete structures and its repair materials

Abstract

This application provides a method for repairing the wet interface of marine concrete structures and its repair material. The repair material comprises 100-150 parts of hydroxyl-terminated polydimethylsiloxane, 20-60 parts of butyl rubber, 30-80 parts of sulfoaluminate cement, 5-15 parts of crosslinking agent, 2-8 parts of latent catalytic system, 3-10 parts of tackifying resin, and 20-100 parts of filler. The latent catalytic system is prepared by complexing an organotin catalyst with a chelating agent, achieving long-term stability at room temperature and triggering a curing reaction upon exposure to moisture and temperature. The repair material can be directly applied under wet interface conditions with a substrate surface moisture content of 5%-20%, without the need for drying. The application process is simple and quick. This method is suitable for in-situ repair of concrete structures in tidal zones, underwater concrete structures, offshore platform pile foundations, and wharf facilities. It can be applied under wet interface conditions with a substrate surface moisture content of 5%-20%, without the need for drying, and can be used for corrosion protection, crack sealing, damage repair, and steel reinforcement rust prevention in marine concrete structures.

Description

Technical Field

[0001] This application relates to the field of marine engineering technology, and in particular to a method for repairing the wet interface of marine concrete structures and its repair materials. Background Technology

[0002] With the continuous expansion of my country's marine engineering construction scale, concrete structures such as offshore platforms, cross-sea bridges, wharf facilities, subsea tunnels, and offshore wind power foundations face severe durability challenges during service. The coupled effects of multiple factors in the marine environment, including chloride ion corrosion, sulfate corrosion, freeze-thaw cycles, and wave impact, lead to surface spalling, crack propagation, and steel reinforcement corrosion in concrete structures, seriously threatening their safety and service life. Therefore, monitoring and repair of these concrete structures are necessary.

[0003] Currently, the main repair materials for marine concrete structures include polymer mortar, epoxy resin mortar, and rapid-hardening cement mortar. Polymer mortar has good flexibility and bonding properties, but it is prone to hydrolysis and aging under long-term seawater immersion, resulting in insufficient durability. Epoxy resin mortar has excellent bonding strength and impermeability, but solvent-based epoxy resins pose environmental pollution problems due to the volatilization of organic solvents during construction, and must be applied to a dry substrate surface, placing stringent requirements on the construction environment. Water-based epoxy resins, while environmentally friendly, have a slow curing speed and low early strength, making them unsuitable for the rapid repair needs of marine engineering projects. Rapid-hardening cement mortar, although setting and hardening quickly, has poor flexibility and is prone to cracking and peeling under temperature stress and wave impact.

[0004] The biggest technical challenge in repairing marine concrete structures is the construction at wet interfaces. Concrete surfaces in tidal zones and underwater areas are constantly damp or submerged. Traditional repair materials require a dry substrate surface to ensure effective adhesion, necessitating measures such as cofferdam drainage and compressed air drying, which are costly, time-consuming, and in some cases impossible. Even with drying measures, the presence of significant internal moisture in the concrete can easily lead to the formation of an interfacial water film between the repair material and the substrate, causing adhesion failure. Furthermore, if construction is required in tidal zones, the material needs to achieve initial positioning quickly to prevent being washed away by seawater, while simultaneously maintaining long-term flexibility to accommodate structural deformation and sufficient strength to resist wave impact. These multiple performance requirements pose extremely high challenges to material design and construction processes.

[0005] Therefore, there is a need to provide an improved technical solution that addresses the shortcomings of the existing technology. Summary of the Invention

[0006] The purpose of this application is to provide a construction method and repair material for repairing the wet interface of marine concrete structures, so as to solve or alleviate the problems of existing marine concrete repair materials and construction processes, which require construction on a dry substrate surface, have poor storage stability, are difficult to control during the curing process, and are difficult to balance flexibility and strength.

[0007] To achieve the above objectives, this application provides the following technical solution: A repair material for the wet interface of marine concrete structures, comprising the following raw materials in parts by weight: Hydroxyl-terminated polydimethylsiloxane 100-150 parts, butyl rubber 20-60 parts, sulfoaluminate cement 30-80 parts, crosslinking agent 5-15 parts, latent catalytic system 2-8 parts, tackifying resin 3-10 parts, and filler 20-100 parts; The latent catalytic system is prepared by complexing an organotin catalyst and a chelating agent at a mass ratio of 1:0.5-1:2; the organotin catalyst is one or more of dibutyltin dilaurate and stannous octoate; the chelating agent is one or more of acetylacetone, sodium diacetylacetone, and salicylaldehyde acetylacetonate; the latent catalytic system is stable at room temperature and is triggered to solidify when exposed to the combined effects of moisture and temperature.

[0008] The complex formed by the organotin catalyst and the chelating agent (i.e., the latent catalytic system) is inactive at room temperature, allowing the material to be stored in sealed packaging for more than 12 months without curing, thus solving the technical problem of short shelf life of traditional single-component silicone rubber. When the material is exposed to moisture and a suitable temperature environment after application, the chelating agent gradually releases the catalyst, triggering the curing reaction, achieving a balance between storage stability and curing convenience.

[0009] Preferably, the marine concrete structure wet interface repair material comprises the following raw materials in parts by weight: Hydroxyl-terminated polydimethylsiloxane 120-140 parts, butyl rubber 30-50 parts, sulfoaluminate cement 40-60 parts, crosslinking agent 8-12 parts, latent catalytic system 3-6 parts, tackifying resin 5-8 parts, and filler 40-80 parts.

[0010] Furthermore, the viscosity of the hydroxyl-terminated polydimethylsiloxane is 5000-50000 mPa·s; the Mooney viscosity of the butyl rubber is 30-60; the crosslinking agent is one or more of tetraethyl orthosilicate, methyltrimethoxysilane, and vinyltrimethoxysilane; the tackifying resin is one or more of rosin-modified phenolic resin, terpene resin, and C5 petroleum resin; and the filler is one or more of calcium carbonate, talc, and silica fume.

[0011] Furthermore, the preparation method of the latent catalytic system is as follows: the organotin catalyst and the chelating agent are mixed under an inert atmosphere and stirred for 30-120 minutes to obtain a complex, which is the latent catalytic system.

[0012] Furthermore, the preparation method of the marine concrete structure wet interface repair material is as follows: hydroxyl-terminated polydimethylsiloxane, butyl rubber and tackifying resin are mixed evenly at 60-90℃ to form a base adhesive; then filler, sulfoaluminate cement and crosslinking agent are added in sequence and stirred evenly; finally, when the temperature drops below 40℃, a latent catalytic system is added, and after vacuum degassing, the mixture is sealed and packaged to obtain a single-component latent repair material.

[0013] This invention also proposes a method for repairing the wet interface of marine concrete structures, using the aforementioned repair material for the wet interface of marine concrete structures, including the following steps: Step 1: Clean the wet interface of the marine concrete structure to be repaired, removing marine organisms, loose concrete and oil stains attached to the surface, while keeping the wet interface moist. Step 2: Apply the marine concrete structure wet interface repair material to the wet interface to be repaired, press it to make full contact with the marine concrete structure wet interface repair material, and use mechanical anchors to assist in fixation. Step 3: Curing is carried out in an environment with a relative humidity of 60%-95% and a temperature of 5-35℃, so that the material completes the staged curing process of initial bonding of butyl rubber, moisture curing of silicone rubber and hydration hardening of cement in sequence, forming a composite protective layer with both flexibility and rigidity; avoid external disturbance to the marine concrete structure wet interface repair material within 6 hours after construction.

[0014] The wet interface construction capability of the marine concrete structure wet interface repair material stems from the hydrophilic design of the material system and the drainage effect of butyl rubber. This allows the material to effectively wet the substrate surface and establish a strong interfacial bond. During curing, it undergoes phased curing: the initial curing stage, within 6 hours after application, relies on the initial tack of butyl rubber for rapid positioning and temporary bonding, effectively preventing the material from being washed away by seawater in tidal zones or creeping down vertically; the intermediate curing stage, within 6-48 hours after application, involves the silicone rubber undergoing a condensation reaction under moisture, forming a flexible elastic network that provides permanent flexible adhesion, adapting to the temperature and mechanical deformation of the structure; the late curing stage, within 48 hours to 7 days after application, involves the gradual hydration and hardening of sulfoaluminate cement, forming a rigid skeleton and mechanical anchoring force, providing long-term structural strength; complete curing requires 14-28 days, with the curing rate accelerating with increasing temperature and humidity. The synergistic effect of the three components—butyl rubber, silicone rubber, and sulfoaluminate cement—over time allows the material to perform functions such as rapid positioning, flexible bonding, and rigid reinforcement at different curing stages, forming a synergistic effect over time. This achieves an organic unity of construction convenience, flexibility, and strength, while also enabling direct construction under wet interface conditions.

[0015] Furthermore, in step one, high-pressure water jets, wire brushes, or handheld power tools are used to remove the deposits on the surface of the wet interface to be repaired. After cleaning, the roughness Ra of the wet interface to be repaired is controlled at 6.3-25μm, the surface moisture content is controlled at 5%-20%, and the pH value is controlled within the range of 7-13. For severely corroded exposed steel bars, rust removal treatment is performed and anti-rust primer is applied.

[0016] Furthermore, in step two, the repair material is made into a tape or sheet with a thickness of 2-10mm, or directly applied to the surface to be repaired with a thickness of 3-15mm; when applying, a pressure of 0.1-0.5MPa is applied to ensure that the material is in full contact with the substrate; for vertical and top surface construction, anchor nails, stainless steel mesh or fiberglass mesh are used for auxiliary fixing, with an anchor spacing of 100-300mm.

[0017] Preferably, the method for repairing the wet interface of marine concrete structures adopts differentiated construction methods for different marine environmental areas: In atmospheric and splash zones, the repair material thickness is 3-8 mm, and the curing time is no less than 7 days. In underwater zones, the repair material is made into sheets with a thickness of 8-15 mm, and an underwater rapid application process is used, with the assistance of divers or underwater robots, and the curing time is no less than 21 days. In tidal zones, the repair material thickness is 5-10 mm, and construction begins 2-3 hours before low tide, with a curing time of no less than 14 days. The repair method of this invention is particularly suitable for the most severe marine environment, the tidal zone. By starting construction 2-3 hours before low tide, utilizing the rapid positioning capability of butyl rubber, the material is initially fixed before the tide rises, and then continuously cured in a humid environment, fully utilizing the material's wet-curing characteristics. This construction strategy, which cleverly utilizes the natural tidal patterns, enables the efficient repair of structures in the tidal zone, which is originally the most difficult to repair.

[0018] Preferably, for large-area repair work, a zoned and segmented construction method should be adopted; the area of ​​a single construction operation should be controlled within 10-50m². 2 The construction time interval between adjacent construction areas is 12-24 hours, and the overlap width is 50-100mm to ensure the continuity and consistency of the overall protective layer.

[0019] Furthermore, the construction method for repairing the wet interface of marine concrete structures also includes step four, quality inspection: bond strength testing, integrity inspection, and protective effect evaluation of the repaired protective layer are conducted. The main test types include bond strength testing, integrity inspection, and protective effect evaluation. The bond strength test uses the pull-out method, requiring a bond strength ≥1.5 MPa and a failure mode of cohesive failure within the concrete. The integrity inspection uses a combination of visual inspection and tapping to ensure the protective layer is free of voids, delamination, and cracks. The protective effect evaluation includes measuring chloride ion penetration depth, electrochemical impedance, and cathodic protection potential to ensure effective protection of the reinforcing steel.

[0020] This invention provides a complete construction process system and quality control methods. A standardized operating procedure is established, encompassing substrate surface treatment, material attachment and fixation, curing and maintenance, and quality inspection. Differentiated construction parameters are developed for different marine environments to ensure optimal material performance under various conditions. The construction process is simple and quick, with a single application area of ​​10-50 square meters, suitable for large-area repairs. For emergency repairs, the material can achieve initial curing within 6 hours, rapidly restoring the structure's protective function.

[0021] The technical solution of this application has the following beneficial effects: This invention achieves long-term storage stability of the repair material through the design of a latent catalytic system. By leveraging the synergistic effect of butyl rubber, silicone rubber, and sulfoaluminate cement, a staged curing mechanism is creatively established, enabling direct application under wet interface conditions. This repair material can be applied to substrates with a surface moisture content of 5%-20%, eliminating the need for drying. This overcomes the limitation of traditional repair materials requiring application to dry surfaces, offering significant practical value for repairing concrete structures in tidal zones and underwater areas. It substantially reduces construction costs, shortens construction time, and enables repair operations in situations where drying measures are not feasible.

[0022] This invention achieves excellent comprehensive performance through optimized material composition and precise control of construction technology. It exhibits a stable storage period of ≥12 months at room temperature, and the bond strength of the repair material reaches over 2.0 MPa at 28 days, meeting engineering application requirements. With an elongation at break greater than 150%, it possesses good flexibility, adapting to structural deformation without cracking. It exhibits excellent resistance to seawater immersion, remaining unaffected by hydrolysis and aging during long-term use in seawater environments. Its high chloride ion penetration resistance effectively prevents chloride ion diffusion to the steel reinforcement surface, providing rust prevention and protection. The multifunctional integrated characteristics of the repair material enable it to simultaneously achieve comprehensive effects of protection, repair, and reinforcement.

[0023] This invention has broad engineering application prospects and can be applied to the maintenance and emergency repair of various marine concrete structures such as offshore platforms, cross-sea bridges, dock facilities, subsea tunnels, and offshore wind power foundations. It can also be used for the repair of hydraulic structures such as reservoir dams, hydropower stations, and sewage treatment facilities. The single-component nature of the material and the simple construction process make it suitable for rapid on-site application, with relatively low technical requirements for operators, which facilitates the promotion and popularization of the technology. In terms of economic benefits, compared with traditional cofferdam drainage and drying construction methods, this invention can save 30%-50% of project costs and shorten the construction period by 50%-70%, demonstrating significant economic advantages.

[0024] In summary, this invention systematically solves the technical challenges of repairing the wet interface of marine concrete structures by organically combining material formulation innovation, curing mechanism innovation, and construction process innovation. It provides an efficient and reliable technical solution for the maintenance and emergency repair of marine engineering infrastructure, and has significant theoretical and practical value. Attached Figure Description

[0025] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. Wherein: Figure 1 This is the SEM morphology of the organic-inorganic composite interface after the repair material of Example 1 of the present invention has been cured.

[0026] Figure 2 The image shows the SEM morphology of ettringite crystals formed by the hydration of sulfoaluminate cement in the repair material of Example 1 of the present invention. Detailed Implementation

[0027] The inventors discovered in their research that the fundamental reason why traditional marine concrete repair materials are difficult to apply at wet interfaces lies in the interfacial water film problem between the material and the substrate, as well as the material's lack of rapid positioning capability in the early stages of construction. Furthermore, single-function repair materials cannot meet the phased performance requirements of rapid initial positioning, flexible bonding in the middle stage, and rigid reinforcement in the marine environment. If the initial tack of butyl rubber, the moisture-curing properties of silicone rubber, and the rigid framework function of cement can be organically combined, and long-term storage stability and rapid on-site curing can be achieved through latent catalytic technology, constructing a multi-dimensional synergistic mechanism in both time and space dimensions, it will help solve or improve the aforementioned problems existing in the current repair of marine concrete structures. Therefore, this application proposes a marine concrete structure wet interface repair material and repair construction method.

[0028] A repair material for the wet interface of marine concrete structures, comprising the following raw materials in parts by weight: Hydroxyl-terminated polydimethylsiloxane 100-150 parts (e.g., 100, 110, 120, 130, 140, 150 parts), butyl rubber 20-60 parts (e.g., 20, 30, 40, 50, 60 parts), sulfoaluminate cement 30-80 parts (e.g., 30, 40, 50, 60, 70, 80 parts), crosslinking agent 5-15 parts (e.g., 5, 8, 10, 12, 15 parts), latent catalytic system 2-8 parts (e.g., 2, 3, 4, 5, 6, 7, 8 parts), tackifying resin 3-10 parts (e.g., 3, 5, 7, 8, 10 parts), and filler 20-100 parts (e.g., 20, 40, 60, 80, 100 parts). The latent catalytic system is prepared by complexing an organotin catalyst with a chelating agent at a mass ratio of 1:0.5-1:2 (e.g., 1:0.5, 1:0.8, 1:1, 1:1.5, 1:2); the organotin catalyst is one or more of dibutyltin dilaurate and stannous octoate; the chelating agent is one or more of acetylacetone, sodium diacetylacetone, and salicylaldehyde acetylacetonate; the latent catalytic system is stable at room temperature and is triggered to solidify when exposed to moisture and temperature.

[0029] One of the core innovations of this application is the design of a latent catalytic system, which achieves a harmonious balance between long-term room-temperature storage stability and rapid curing triggered by moisture. The complex formed by the organotin catalyst and the chelating agent (i.e., the latent catalytic system) is inactive at room temperature, allowing the material to be stored for more than 12 months without curing under sealed packaging, thus solving the technical problem of short shelf life of traditional single-component silicone rubber. When the material is exposed to moisture and a suitable temperature environment after application, the chelating agent gradually releases the catalyst, triggering the curing reaction, achieving a balance between storage stability and curing convenience. The principle is as follows: organotin catalysts are highly efficient catalysts for the room-temperature vulcanization reaction of silicone rubber, but ordinary organotin catalysts continuously exert their catalytic effect in the material, causing the material to slowly cure during storage. This application complexes the organotin catalyst with a chelating agent, whose coordination effect shields the active center of the catalyst, leaving it inactive under dry conditions at room temperature. When the material is exposed to a humid environment after application, water molecules gradually compete with the chelating agent for coordination, causing the chelating agent to dissociate from the catalyst, restoring the catalyst's activity and initiating the condensation curing reaction of the silicone rubber.

[0030] Preferably, the marine concrete structure wet interface repair material comprises the following raw materials in parts by weight: Hydroxyl-terminated polydimethylsiloxane 120-140 parts, butyl rubber 30-50 parts, sulfoaluminate cement 40-60 parts, crosslinking agent 8-12 parts, latent catalytic system 3-6 parts, tackifying resin 5-8 parts, and filler 40-80 parts.

[0031] The hydroxyl-terminated polydimethylsiloxane (PDMS) in the marine concrete structure wet interface repair material is the main polymer, providing the material with flexibility, weather resistance, and seawater resistance. The terminal hydroxyl groups of the PDMS undergo a condensation reaction with a crosslinking agent under the action of a latent catalyst, forming a three-dimensional network structure, which is the core mechanism of the material's moisture curing. By selecting a suitable viscosity range for the PDMS, the material's workability and mechanical properties after curing can be balanced. The viscosity of the PDMS is 5000-50000 mPa·s (e.g., 5000 mPa·s, 10000 mPa·s, 20000 mPa·s, 30000 mPa·s, 40000 mPa·s, 50000 mPa·s), and the hydroxyl content is 0.2-0.8 wt% (e.g., 0.2 wt%, 0.4 wt%, 0.6 wt%, 0.8 wt%).

[0032] Butyl rubber possesses excellent initial tack, airtightness, and water resistance, playing multiple roles in material systems: In the initial stages of construction, its initial tack enables rapid positioning and temporary bonding of the material, effectively preventing it from being washed away by seawater in tidal zones or creeping down vertically; as an elastic phase dispersed in a silicone rubber matrix, it improves the material's flexibility and impact resistance; and it creates a drainage effect at interfaces, facilitating adhesion of the material to wet substrate surfaces. The butyl rubber has a Mooney viscosity of 30-60 (e.g., 30, 40, 50, 60) and an unsaturation of less than 2%. At this viscosity, butyl rubber can be uniformly dispersed in the material system while maintaining sufficient initial tack.

[0033] The specific surface area of ​​sulfoaluminate cement is 350-450 m². 2 / kg (e.g., 350m) 2 / kg, 380m 2 / kg, 410m 2 / kg, 440m 2 / kg, 450m 2 Sulfoaluminate cement has a high initial setting time of 15-45 minutes (e.g., 15 minutes, 25 minutes, 35 minutes, 45 minutes) compared to ordinary silicate cement. It is characterized by rapid hardening, early strength, and micro-expansion, making it particularly suitable for repair applications in marine environments.

[0034] The crosslinking agent is one or a mixture of tetraethyl orthosilicate, methyltrimethoxysilane, and vinyltrimethoxysilane. The crosslinking agent provides crosslinking sites and undergoes a condensation reaction with the terminal hydroxyl groups of the hydroxyl-terminated polydimethylsiloxane to form a three-dimensional network structure. Tetraethyl orthosilicate hydrolyzes to form tetrafunctional silanols, which can significantly increase the crosslinking density and material strength; however, excessive use can lead to increased brittleness. Methyltrimethoxysilane and vinyltrimethoxysilane are trifunctional crosslinking agents, providing a moderate crosslinking density and maintaining the material's flexibility. By using different crosslinking agents in combination, the mechanical properties of the material can be precisely controlled.

[0035] The tackifying resin is one or more mixtures of rosin-modified phenolic resin, terpene resin, and C5 petroleum resin, with a softening point of 80-120℃ (e.g., 80℃, 90℃, 100℃, 110℃, or 120℃). The tackifying resin enhances the initial adhesion between the material and a wet substrate by increasing the material's adhesion and cohesive strength, thus assisting butyl rubber in its rapid positioning function.

[0036] The filler is one or a mixture of calcium carbonate, talc, and silica fume, with a particle size of 200-1000 mesh (e.g., 200 mesh, 400 mesh, 600 mesh, 800 mesh, or 1000 mesh). The filler plays a role in reducing costs, regulating rheological properties, improving dimensional stability, and enhancing mechanical strength in the material. Different types and particle sizes of fillers have different effects on material properties; by using a combination of different fillers, the overall performance of the material can be optimized while controlling costs.

[0037] Furthermore, the preparation method of the latent catalytic system is as follows: the organotin catalyst and the chelating agent are mixed under an inert atmosphere and stirred at 50-80℃ (e.g., 50℃, 60℃, 70℃, 80℃) for 30-120 minutes (e.g., 30 minutes, 60 minutes, 90 minutes, 120 minutes) to obtain a complex, which is the latent catalytic system. The mass ratio of the organotin catalyst to the chelating agent directly affects the latent effect and triggering sensitivity of the catalyst.

[0038] Furthermore, the preparation method of the marine concrete structure wet interface repair material is as follows: Hydroxyl-terminated polydimethylsiloxane, butyl rubber, and tackifying resin are mixed uniformly at 60-90℃ (e.g., 60℃, 70℃, 80℃, 90℃) to form a base adhesive; then filler, sulfoaluminate cement, and crosslinking agent are added sequentially, and the mixture is stirred uniformly in a planetary mixer; finally, a latent catalytic system is added when the temperature drops below 40℃, and after vacuum degassing, the mixture is sealed and packaged to obtain a single-component latent repair material. The preparation temperature of 60-90℃ softens the butyl rubber and tackifying resin, which is beneficial for their uniform dispersion in silicone oil, forming a stable mixed system. In the order of adding raw materials, the filler is added first to utilize its adsorption effect to stabilize the system; then sulfoaluminate cement is added, and finally the crosslinking agent is added. This order ensures thorough mixing of each component while avoiding premature chemical reactions.

[0039] Latent catalytic systems must be added only when the temperature drops below 40°C. This is because higher temperatures accelerate the dissociation of the catalyst-chelating agent complex, causing the catalyst to prematurely regain activity. Adding the catalyst below 40°C maximizes its latency, ensuring the material's storage stability. Vacuum degassing removes air bubbles introduced during stirring; these bubbles become defects, significantly reducing the material's mechanical properties and protective effect. Sealed packaging isolates the material from moisture, preventing moisture absorption and curing during storage.

[0040] This invention also proposes a method for repairing the wet interface of marine concrete structures, using the aforementioned repair material for the wet interface of marine concrete structures, including the following steps: Step 1: Clean the wet interface of the marine concrete structure to be repaired, removing marine organisms, loose concrete and oil stains attached to the surface, while keeping the wet interface moist. Step 2: Apply the marine concrete structure wet interface repair material to the wet interface to be repaired, press it to make full contact with the marine concrete structure wet interface repair material, and use mechanical anchors to assist in fixation. Step 3: Cure the material under environmental conditions of 60%-95% relative humidity and 5-35℃, allowing it to complete the phased curing process of initial bonding of butyl rubber, moisture curing of silicone rubber, and hydration hardening of cement, forming a composite protective layer that combines flexibility and rigidity. The curing rate of the repair material increases with rising temperature and humidity, providing flexibility for construction under different climatic conditions. It is important to note that the marine concrete structure wet interface repair material should be protected from external disturbance within 6 hours after construction. Temporary protective covers, waterproof membranes, or other auxiliary measures can be used to protect the material, or the timing of construction should be strictly controlled to ensure that initial curing is completed during low tide. After 6 hours, the marine concrete structure wet interface repair material can be exposed to the normal marine environment and continue to complete the curing process in a humid or underwater environment.

[0041] The wet interface construction capability of the marine concrete structure wet interface repair material stems from the hydrophilic design of the material system and the drainage effect of butyl rubber. This allows the material to effectively wet the substrate surface and establish a strong interfacial bond. The material cures in stages during the curing process: ① Initial curing stage (within 6 hours after application): The initial tack of the butyl rubber enables rapid positioning and temporary bonding, effectively preventing the material from being washed away by seawater in tidal zones or creeping down vertically; ② Mid-term curing stage (6-48 hours after application): This is the main period for the moisture curing of silicone rubber. Moisture in the air diffuses through the material surface to the interior, triggering the activation of a latent catalyst. The catalytically terminated hydroxyl polydimethylsiloxane undergoes a condensation reaction with the crosslinking agent, forming an elastic network. During this stage, the material's elastic modulus and tensile strength increase rapidly, while the elongation at break remains at a high level, forming a flexible adhesive layer. An environmental condition with a relative humidity of 60%-95% provides sufficient moisture for moisture curing, and the temperature range of 5-35℃ covers most actual temperatures in marine environments. ③ The post-construction curing stage, lasting 48 hours to 7 days after construction, is the main period of hydration and hardening of sulfoaluminate cement. The cement hydration reaction forms a rigid skeleton structure, providing the material with mechanical strength and anchoring force. Cement hydration products fill the pores of the silicone rubber matrix, forming an interpenetrating network structure with the silicone rubber. This organic-inorganic composite structure combines flexibility and rigidity, adapting to small structural deformations while withstanding external loads. Complete curing requires 14-28 days, during which time the material's various properties continue to improve and tend to stabilize.

[0042] Furthermore, in step one, high-pressure water jets, wire brushes, or handheld power tools are used to remove the adhering substances from the surface of the wet interface to be repaired. After cleaning, the roughness Ra of the wet interface to be repaired is controlled at 6.3-25μm, which increases the specific surface area of ​​the substrate and the mechanical interlocking effect, which is beneficial to the adhesion of the material. The moisture content of the surface of the wet interface to be repaired is controlled at 5%-20%, which ensures the practical feasibility of wet interface construction without weakening the bonding strength due to excessive moisture. The pH value is controlled within the range of 7-13, which is also the pH environment of normal concrete. For severely corroded exposed steel bars, rust removal treatment is performed and anti-rust primer is applied.

[0043] Furthermore, in step two, the repair material is pre-formed into tape or sheet-like products with a thickness of 2-10mm, or directly applied to the surface to be repaired with a thickness of 3-15mm. During application, a pressure of 0.1-0.5MPa is applied to ensure full contact between the material and the substrate, expelling air bubbles and water films at the interface, without causing excessive deformation due to excessive pressure. Pressure can be applied manually, by rolling, or mechanically, depending on the actual situation. For vertical and top surfaces, mechanical anchors such as anchor nails, stainless steel mesh, or fiberglass mesh are used for fixation, with an anchor spacing of 100-300mm. Pre-formed repair materials facilitate transportation and construction, and are suitable for regularly shaped repair areas; spreadable repair materials are more adaptable, and the application thickness can be adjusted according to the irregular shape of the substrate.

[0044] Preferably, the method for repairing the wet interface of marine concrete structures adopts differentiated construction methods for different marine environmental areas: ① Although the atmospheric and splash zones are also affected by the marine environment, the substrate is relatively dry, so the repair material thickness can be thinner, 3-8mm, and the curing time should be no less than 7 days. ② The underwater zone is submerged in seawater for a long time, requiring a repair material thickness of 8-15mm. An underwater rapid application process should be used, with the assistance of divers or underwater robots. The curing time should be no less than 21 days, as the underwater environment has sufficient moisture but relatively low temperature, resulting in slower curing. ③ The tidal zone is the harshest area in the marine environment, experiencing periodic wet-dry cycles, temperature changes, and wave impacts. A repair material thickness of 5-10mm is required to provide stronger protection. Construction should begin 2-3 hours before low tide, and the curing time should be no less than 14 days to ensure the material fully cures and forms a stable protective layer. The repair method of this invention is particularly suitable for the tidal zone, the harshest marine environment. By starting construction 2-3 hours before low tide, the materials are attached and initially pressed before the tide rises. The rapid positioning capability of butyl rubber is used to achieve initial fixation before the tide rises. After the tide rises, the materials continue to cure in the water, making full use of the material's wet curing characteristics. The seawater after high tide gently covers and continuously soaks the area, without generating strong external impacts, unlike the external disturbances mentioned earlier. This construction strategy cleverly utilizes the natural tidal patterns, enabling the efficient repair of structures in the tidal range, which are usually the most difficult to repair.

[0045] Preferably, for large-area repair work, a zoned and segmented construction method should be adopted; the area of ​​a single construction operation should be controlled within 10-50m². 2 The construction time interval between adjacent construction areas is 12-24 hours, and the overlap width is 50-100mm to ensure the continuity and consistency of the overall protective layer.

[0046] Furthermore, the construction method for repairing the wet interface of marine concrete structures also includes step four, quality inspection: bond strength testing, integrity inspection, and protective effect evaluation of the repaired protective layer; the main test types are bond strength testing, integrity inspection, and protective effect evaluation. The bond strength test uses the pull-out method, requiring a bond strength ≥1.5 MPa, and the failure mode to be cohesive failure of the concrete rather than interfacial bond failure. This indicates that the bond strength between the repair material and the substrate is higher than the strength of the concrete itself, and the repair layer and the substrate form a strong integrated structure. The integrity inspection uses visual inspection combined with tapping to ensure that the protective layer is free of voids, delamination, and cracks. The protective effect evaluation includes measuring chloride ion penetration depth, electrochemical impedance, and cathodic protection potential to ensure effective protection of the reinforcing steel. Chloride ion penetration depth reflects the material's impermeability; a smaller penetration depth indicates a better barrier effect against chloride ions. Electrochemical impedance testing evaluates the material's inhibitory effect on the electrochemical corrosion process of the reinforcing steel; a larger impedance value indicates a lower corrosion rate. Cathodic protection potential monitoring confirms that the reinforcing steel is under cathodic protection, thus avoiding or mitigating electrochemical corrosion. These testing methods comprehensively evaluate the repair effect from different perspectives, ensuring that the repair layer can effectively protect the concrete structure for a long time.

[0047] This invention provides a complete construction process system and quality control methods. A standardized operating procedure is established, encompassing substrate surface treatment, material attachment and fixation, curing and maintenance, and quality inspection. Differentiated construction parameters are developed for different marine environments to ensure optimal material performance under various conditions. The construction process is simple and quick, with a single application area of ​​10-50 square meters, suitable for large-area repairs. For emergency repairs, the material can achieve initial curing within 6 hours, rapidly restoring the structure's protective function.

[0048] The main raw materials used in the following examples and comparative examples are: Hydroxyl-terminated polydimethylsiloxane was purchased from Dow Corning, model DC-5609, viscosity 15000 mPa·s; butyl rubber was from ExxonMobil, model EXXON Butyl 268, Mooney viscosity 45; sulfoaluminate cement was selected from Tangshan Arctic Bear Building Materials Co., Ltd., grade 42.5R, specific surface area 380-420 m² / g. 2 / kg, initial setting time 25-35 minutes; tetraethyl orthosilicate was purchased from Sinopharm Chemical Reagent Co., Ltd., specification analytical grade; dibutyltin dilaurate was from TIB Chemicals AG, purity ≥95%; acetylacetone was purchased from Shanghai Aladdin Reagent Co., Ltd., purity ≥99%; rosin-modified phenolic resin was a product of Haimings Chemical Co., Ltd., softening point 100℃; calcium carbonate was from Guangxi Hezhou Calcium Carbonate Plant, particle size 800 mesh; silica powder was purchased from Lianyungang Non-metallic Mining Co., Ltd., particle size 1000 mesh.

[0049] In each example and comparative example, systematic performance tests are carried out on the repair material, and the test items include storage stability, initial setting time, bonding strength, elongation at break, chloride ion penetration depth and long-term durability. The test methods are as follows: Storage stability test: accelerated aging method is adopted; after the repair material is sealed and packaged, the storage stability is evaluated by high-temperature accelerated aging test. The specific method is: store the sample in a constant temperature oven at 50±2°C, sample and detect the viscosity change rate and curing performance at 7 days, 14 days, 28 days and 56 days respectively, and observe whether gelation, phase separation and other phenomena occur. According to the Arrhenius equation, accelerated aging at 50°C for 28 days is approximately equivalent to storage at normal temperature of 25°C for 6 months, and accelerated aging at 50°C for 56 days is approximately equivalent to storage at normal temperature of 25°C for 12 months. Judgment criteria: after accelerated aging at 50°C for 56 days, it is judged as qualified if the viscosity change rate is ≤20% and no gelation occurs; it is judged as unqualified if gelation or phase separation occurs within 56 days.

[0050] Initial setting time test: coat the repair material on the surface of a concrete substrate with a moisture content of 10%, place it in an environment with a relative humidity of 80% and a temperature of 25°C, and conduct detection every 30 minutes by the finger-touch method. When the material surface is not sticky to fingers and can withstand slight pressure, record this time as the initial setting time. Test each sample 3 times and take the average value.

[0051] Bonding strength test: according to the standard method of GB / T 50728, prepare a concrete test block of 100mm×100mm×50mm, control the surface moisture content at 10%±2%, evenly coat the repair material with a coating thickness of 5mm, cure under standard conditions for 28 days, carry out bonding strength test with a pull-out tester, adopt concrete cohesive failure as the failure mode, record the failure load and calculate the bonding strength. Test 6 samples for each material, remove the maximum value and the minimum value, and then take the average value.

[0052] Elongation at break test: according to the standard of GB / T 528 ("Determination of tensile stress-strain properties for vulcanized rubber or thermoplastic rubber"), prepare the repair material into dumbbell-shaped samples, cure for 28 days under standard conditions, carry out the test with an electronic tensile testing machine at a tensile speed of 500mm / min, and record the elongation at break. Test 5 samples for each material and take the average value.

[0053] Chloride ion penetration depth test: coat the repair material on the surface of a 100mm×100mm×50mm concrete test block with a coating thickness of 5mm, after curing for 28 days, immerse the test block in 3.5% NaCl solution, take samples at regular intervals (30 days, 60 days, 90 days), split the sample and spray 0.1mol / L AgNO₃ solution for color development, and measure the chloride ion penetration depth.

[0054] Long-term durability test: The repaired sample was subjected to a seawater immersion-drying cycle test. Each cycle included 3 days of immersion (in 3.5% NaCl solution) and 4 days of drying (in an oven at 40°C). After 30 cycles, the bond strength retention rate, surface integrity and chloride ion permeation resistance were tested.

[0055] The present application will now be described in detail with reference to the embodiments.

[0056] Example 1 The marine concrete structure wet interface repair material of this embodiment comprises, by weight, the following components: 100 parts of hydroxyl-terminated polydimethylsiloxane, 20 parts of butyl rubber, 30 parts of sulfoaluminate cement, 5 parts of crosslinking agent, 2 parts of latent catalytic system, 3 parts of tackifying resin, and 20 parts of filler; the viscosity of hydroxyl-terminated polydimethylsiloxane is 15000 mPa·s, the Mooney viscosity of butyl rubber is 45; the crosslinking agent is tetraethyl orthosilicate; the tackifying resin is rosin-modified phenolic resin; and the filler is calcium carbonate.

[0057] The preparation method of the latent catalytic system includes: mixing dibutyltin dilaurate and acetylacetone at a mass ratio of 1:0.5 under nitrogen protection, stirring at 50°C for 30 minutes to obtain a pale yellow complex.

[0058] The preparation process of the repair material is as follows: Hydroxyl-terminated polydimethylsiloxane, butyl rubber, and tackifying resin are mixed evenly at 60°C for 60 minutes to form a base compound. Then, fillers are added sequentially and stirred for 30 minutes. Sulfoaluminate cement is added and stirred for another 40 minutes. A crosslinking agent is added and stirred for 20 minutes to mix evenly. Finally, when the temperature drops to 35°C, a latent catalytic system is added, stirred for 15 minutes, and then vacuum degassed for 30 minutes. The mixture is then sealed and packaged to obtain a single-component latent repair material.

[0059] Indoor construction simulations were conducted. To simulate concrete structures with attached organisms in a marine environment, specialized concrete test blocks were first fabricated. The test blocks, measuring 300mm × 300mm × 100mm, were cast using C40 ordinary Portland cement concrete. After standard curing for 28 days, the test blocks were placed in an artificially simulated marine environment for degradation treatment. The degradation treatment method involved immersing the test blocks in a 3.5% NaCl solution for 7 days, then placing them in an environment with 85% relative humidity and 25℃ for 7 days. This wet-dry cycle was repeated 10 times to create a loose layer on the surface of the test blocks, similar to that found in a marine environment. Simultaneously, shell fragments and algae (simulated using sodium alginate gel) were artificially attached to the surface of the test blocks to simulate the attachment conditions on the surface of a real marine concrete structure.

[0060] The construction method in this embodiment includes the following steps: Step 1, Substrate Surface Treatment: High-pressure water jet with a pressure of 15MPa is used to remove marine organisms and loose layers adhering to the concrete surface. The surface roughness of the cleaned substrate is Ra8μm, the surface moisture content is measured to be 8%, and the pH value is 12.5. Step 2, Material Application: Prepare the repair material into a 3mm thick tape and apply it to the wet concrete surface. Press it down with a hand roller, applying a pressure of approximately 0.2MPa to ensure full contact between the material and the substrate. In this embodiment, the wet concrete surface is vertical, so anchor nails are also used for auxiliary fixation, with an anchor spacing of 150mm. Step 3, Curing and Maintenance: Curing is carried out under environmental conditions of 80% relative humidity and 25℃. An initial inspection is conducted 4 hours after application; the material has achieved preliminary positioning. After 24 hours, the material surface is dry and has good elasticity. The main curing process is completed after 7 days.

[0061] Step 4, Quality Inspection: Conduct a quality inspection 28 days after the repair is completed.

[0062] The test results were as follows: storage stability > 12 months, initial curing time 5.5 hours, 28-day bond strength 2.1 MPa, no hollow areas or delamination found during visual inspection and tapping; elongation at break 165%, 90-day chloride ion penetration depth 4.8 mm, and bond strength retention rate 88% after 30 cycles. SEM observation was performed on the cured repair material. Figure 1 The SEM morphology (magnification 40,000x) of the organic-inorganic composite interface after the repair material has cured. Figure 2 The SEM morphology (magnification 30,000x) of ettringite crystals formed by the hydration of sulfoaluminate cement in the repair material shows that the organic phase fills the gaps between inorganic particles / crystals, forming a dense bond.

[0063] Example 2 The difference between this embodiment and Embodiment 1 lies in the different raw material components, the different crosslinking agent, the different tackifying resin, the different filler components and amounts, and the different construction methods.

[0064] The marine concrete structure wet interface repair material of this embodiment comprises the following components by weight: 120 parts of hydroxyl-terminated polydimethylsiloxane, 30 parts of butyl rubber, 40 parts of sulfoaluminate cement, 8 parts of crosslinking agent, 3 parts of latent catalytic system, 5 parts of tackifying resin, and 40 parts of filler; the crosslinking agent is a mixture of tetraethyl orthosilicate and methyltrimethoxysilane in a 3:1 mass ratio; the tackifying resin is a terpene resin; and the filler is a mixture of calcium carbonate and silica powder in a 3:1 mass ratio.

[0065] The composition and preparation method of the latent catalytic system are the same as in Example 1.

[0066] The preparation process of the repair material is as follows: Hydroxyl-terminated polydimethylsiloxane, butyl rubber, and tackifying resin were mixed evenly at 70°C for 80 minutes to form a base compound. Then, fillers were added sequentially and stirred for 40 minutes. Sulfoaluminate cement was added and stirred for another 50 minutes. A crosslinking agent was added and stirred for 25 minutes to mix evenly. Finally, when the temperature dropped to 38°C, a latent catalytic system was added, stirred for 20 minutes, and then vacuum degassed for 40 minutes. The mixture was then sealed and packaged to obtain a single-component latent repair material.

[0067] Indoor construction simulations were conducted to model concrete structures with exposed, corroded reinforcing steel bars in a marine environment. Concrete test blocks measuring 400mm × 400mm × 150mm were cast using C35 ordinary Portland cement concrete. During casting, a 12mm diameter HRB400 reinforcing steel bar (50mm exposed) was pre-embedded in the center of the block. After 28 days of standard curing, an electrochemical accelerated corrosion method was used to degrade the exposed reinforcing steel bars: the test blocks were placed in a 5% NaCl solution, with the reinforcing steel bar as the anode and a stainless steel plate as the cathode, and an application rate of 100μA / cm² was applied. 2 A constant current density was applied continuously for 14 days, causing significant corrosion of the reinforcing steel and resulting in rust expansion cracks and loosening of the surrounding concrete cover. The deposits on the surface of the test block consisted of rust and loose concrete material produced during the corrosion process.

[0068] The construction method in this embodiment includes the following steps: Step 1: Substrate surface treatment: Use a wire brush to remove the adhering substances from the concrete surface. The surface roughness of the cleaned substrate is Ra15μm, the surface moisture content is measured to be 12%, and the pH value is 11.8. In this embodiment, a concrete simulation test block with pre-embedded rusted steel bars is used. The exposed rusted steel bar areas are treated with rust removal and coated with epoxy anti-rust primer. Step 2, Material Application: Apply the repair material directly to the surface to be repaired, with a thickness of 6mm. Press it firmly with a trowel to ensure full contact between the material and the substrate. For vertical surfaces, use stainless steel mesh for auxiliary fixation, securing the mesh with anchor nails spaced 200mm apart.

[0069] Step 3, Curing and Maintenance: Curing is carried out under environmental conditions of 75% relative humidity and 20℃. An initial inspection is conducted 5 hours after application; the material has achieved preliminary positioning. After 36 hours, the material surface is dry and has good elasticity to the touch. The main curing process is completed after 14 days.

[0070] Step 4, Quality Inspection: Conduct a quality inspection 28 days after the repair is completed.

[0071] The test results were as follows: storage stability > 12 months, initial curing time 4.8 h, 28-day bond strength 2.5 MPa, no defects found during integrity inspection; elongation at break 180%, 90-day chloride ion penetration depth 3.2 mm, bond strength retention rate 92% after 30 cycles; electrochemical impedance spectroscopy showed an impedance value of 8.5 × 10⁻⁶. 5 Ω·cm 2 .

[0072] Example 3 The difference between this embodiment and Example 1 lies in the different raw material components, the different components and amounts of the latent catalytic system, crosslinking agent, tackifying resin, and filler, and the different construction methods.

[0073] The marine concrete structure wet interface repair material of this embodiment comprises, by weight, the following components: 150 parts of hydroxyl-terminated polydimethylsiloxane, 60 parts of butyl rubber, 80 parts of sulfoaluminate cement, 15 parts of crosslinking agent, 8 parts of latent catalytic system, 10 parts of tackifying resin, and 100 parts of filler. The crosslinking agent is a mixture of tetraethyl orthosilicate, methyltrimethoxysilane, and vinyltrimethoxysilane in a 5:3:2 mass ratio; the tackifying resin is a mixture of rosin-modified phenolic resin and terpene resin in a 1:1 mass ratio; and the filler is a mixture of calcium carbonate, silica powder, and talc powder in a 5:3:2 mass ratio.

[0074] The preparation method of the latent catalytic system includes: mixing stannous octoate and acetylacetone at a mass ratio of 1:2 under nitrogen protection, stirring and reacting at 80°C for 120 minutes to obtain a deep yellow complex.

[0075] The preparation process of the repair material is as follows: Hydroxyl-terminated polydimethylsiloxane, butyl rubber, and tackifying resin were mixed evenly at 90°C for 120 minutes to form a base compound. Then, fillers were added sequentially and stirred for 60 minutes. Sulfoaluminate cement was added and stirred for another 70 minutes. A crosslinking agent was added and stirred for 35 minutes to mix evenly. Finally, when the temperature dropped to 40°C, a latent catalytic system was added, stirred for 30 minutes, and then vacuum degassed for 60 minutes. The mixture was then sealed and packaged to obtain a single-component latent repair material.

[0076] Indoor construction simulation was conducted to model the surface peeling of concrete structures in a marine environment. Specialized test blocks were first prepared, measuring 500mm × 500mm × 200mm, using C45 ordinary Portland cement concrete. After standard curing for 28 days, a freeze-thaw cycle treatment was applied: the test blocks were frozen at -18℃ for 4 hours, then immersed in a 3.5% NaCl solution at 20℃ for 4 hours, completing 25 freeze-thaw cycles. This resulted in significant peeling and roughening of the test block surface, with a surface roughness Ra exceeding 20μm. The construction method in this embodiment includes the following steps: Step 1: Substrate surface treatment: Use a handheld power tool to remove the adhering substances from the concrete surface. The surface roughness Ra of the cleaned substrate is 22μm, the surface moisture content is 18%, and the pH value is 10.5.

[0077] Step 2, Material Application: Prepare the repair material into a 10mm thick tape, apply it to the damp concrete surface, and press it down with a hand roller, applying a pressure of approximately 0.4MPa. For top surface application, use a combination of fiberglass mesh and anchor nails for fixation, with anchor spacing of 250mm.

[0078] Step 3: Curing and Maintenance: Curing is carried out under environmental conditions of 90% relative humidity and 30℃. An initial inspection is conducted 3 hours after construction, indicating that the material has achieved preliminary positioning; the silicone rubber curing stage is completed after 48 hours; and cement hydration and hardening are completed after 21 days, reaching the design strength.

[0079] Step 4, Quality Inspection: Conduct a quality inspection 28 days after the repair is completed.

[0080] The test results were as follows: storage stability > 12 months, initial curing time 3.2 h, 28-day bond strength 3.2 MPa, no defects found during integrity inspection; elongation at break 210%, 90-day chloride ion penetration depth 2.1 mm, bond strength retention rate 95% after 30 cycles; electrochemical impedance spectroscopy showed an impedance value of 1.2 × 10⁻⁶. 6 Ω·cm 2 The cathodic protection potential is -320mV (relative to the saturated calomel electrode SCE), and the reinforcing steel is in a good protective state.

[0081] Example 4 The difference between this embodiment and Example 1 lies in the different raw material components, the different components and amounts of the latent catalytic system, crosslinking agent, tackifying resin, and filler, and the different construction methods.

[0082] The marine concrete structure wet interface repair material of this embodiment comprises, by weight, the following components: 130 parts of hydroxyl-terminated polydimethylsiloxane, 40 parts of butyl rubber, 50 parts of sulfoaluminate cement, 10 parts of crosslinking agent, 4 parts of latent catalytic system, 6 parts of tackifying resin, and 60 parts of filler. The crosslinking agent, methyltrimethoxysilane, is compounded with vinyltrimethoxysilane at a mass ratio of 2:1; the tackifying resin is C5 petroleum resin with a softening point of 110℃; and the filler is silica powder.

[0083] The preparation method of the latent catalytic system includes: mixing dibutyltin dilaurate and stannous octoate at a mass ratio of 1:1, then mixing with acetylacetone at a catalyst to chelating agent mass ratio of 1:1.2 under nitrogen protection, and stirring at 65°C for 75 minutes to obtain an orange-yellow complex.

[0084] The prepared repair material was sealed and packaged, and its storage stability was evaluated using a 50℃ accelerated aging test. Performance tests were conducted after storage at a constant temperature of 50℃ for 7, 14, 28, and 56 days. The test results are as follows: Accelerated aging for 7 days: The material has a normal appearance, a viscosity change rate of 1.9%, and good workability; the initial curing time of the repair material is 4.5 hours, the bond strength is 2.7 MPa after 28 days of curing, the elongation at break is 190%, and the penetration depth of chloride ions after 90 days is 2.9 mm.

[0085] Accelerated aging after 14 days: The material has a normal appearance, a viscosity change rate of 4.1%, good workability, and a bond strength of 2.6 MPa after 28 days of curing.

[0086] Accelerated aging after 28 days: The material has a normal appearance, a viscosity change rate of 7.0%, and good workability; the initial curing time of the repair material is 4.8 hours, the bond strength after 28 days of curing is 2.6 MPa, the elongation at break is 186%, and the penetration depth of chloride ions after 90 days is 3.0 mm.

[0087] Accelerated aging after 56 days: The material has a normal appearance, a viscosity change rate of 11.2%, good workability, and a bond strength of 2.5 MPa after 28 days of curing.

[0088] The above test results show that the repair material of this application has good storage stability. According to the Arrhenius equation, accelerated aging at 50°C for 56 days is approximately equivalent to 12 months of storage at room temperature of 25°C. In Example 4, the viscosity change rate after accelerated aging for 56 days was only 11.2%, with no gelation phenomenon, and it still maintained good workability and curing performance.

[0089] The preparation process of the repair material is as follows: Hydroxyl-terminated polydimethylsiloxane, butyl rubber, and tackifying resin were mixed evenly at 75°C for 90 minutes to form a base compound. Then, fillers were added sequentially and stirred for 45 minutes. Sulfoaluminate cement was added and stirred for another 55 minutes. A crosslinking agent was added and stirred for 28 minutes to mix evenly. Finally, when the temperature dropped to 37°C, a latent catalytic system was added, stirred for 22 minutes, and then vacuum degassed for 45 minutes. The mixture was then sealed and packaged to obtain a single-component latent repair material.

[0090] Indoor construction simulation was conducted. To simulate the concrete piers in the tidal zone, concrete test blocks with dimensions of 600mm×400mm×150mm were used. They were cast using C40 marine concrete and cured for 28 days. Then, artificial tidal simulation of degradation was carried out: the lower half of the test block was immersed in artificial seawater (prepared according to ASTM D1141 standard), and the water level was raised and lowered every 12 hours for 60 days to simulate the alternating wet and dry environment of the tidal zone.

[0091] The construction method for repairing concrete bridge piers in the tidal zone based on the above-mentioned test blocks includes the following steps: Step 1, Substrate Surface Treatment: High-pressure water jet is used to remove surface deposits at low tide. The surface roughness of the cleaned substrate is Ra12μm, the surface moisture content is 15%, and the pH value is 11.2. Step 2, Material Application: Begin application 2.5 hours before low tide. Apply the repair material to the surface to be repaired, with a thickness of 8mm. Press and smooth it with a trowel. Secure the material using a combination of stainless steel mesh and anchor nails, with anchor spacing of 180mm. Step 3, Curing and Maintenance: Initially, the material is cured in the air for 3 hours to achieve preliminary positioning; after the tide rises, the material is submerged in seawater to continue curing underwater; after 14 days of tidal cycle curing, the material completes the main curing process. Step 4, Quality Inspection: Conduct a quality inspection 28 days after the repair is completed.

[0092] The test results are as follows: storage stability > 12 months, initial curing time 4.2h, 28-day bond strength 2.8MPa, and good integrity; elongation at break 195%, 90-day chloride ion penetration depth 2.8mm, and bond strength retention rate 93% after 30 cycles.

[0093] Example 5 The difference between this embodiment and Example 1 lies in the different raw material components, the different components and amounts of the latent catalytic system, crosslinking agent, tackifying resin, and filler, and the different construction methods.

[0094] The marine concrete structure wet interface repair material of this embodiment comprises, by weight, the following components: 140 parts of hydroxyl-terminated polydimethylsiloxane, 50 parts of butyl rubber, 60 parts of sulfoaluminate cement, 12 parts of crosslinking agent, 5 parts of latent catalytic system, 8 parts of tackifying resin, and 80 parts of filler. The hydroxyl-terminated polydimethylsiloxane has a viscosity of 30000 mPa·s and a hydroxyl content of 0.6 wt%; the butyl rubber has a Mooney viscosity of 52; the crosslinking agent is a mixture of tetraethyl orthosilicate and methyltrimethoxysilane in a 2:1 mass ratio; the tackifying resin is a terpene resin with a softening point of 105℃; the filler is a mixture of calcium carbonate, talc, and silica fume in a 4:3:3 mass ratio; and the sulfoaluminate cement has a specific surface area of ​​400 m². 2 / kg, initial setting time 30 minutes.

[0095] The preparation method of the latent catalytic system includes: mixing dibutyltin dilaurate and salicylaldehyde acetal at a mass ratio of 1:1.5 under nitrogen protection, and stirring at 70°C for 90 minutes to obtain a brownish-yellow complex. This complex has a stable storage period of up to 18 months under sealed conditions at room temperature.

[0096] The preparation process of the repair material is as follows: Hydroxyl-terminated polydimethylsiloxane, butyl rubber, and tackifying resin were mixed evenly at 80°C for 100 minutes to form a base compound. Then, fillers were added sequentially and stirred for 50 minutes. Sulfoaluminate cement was added and stirred for another 60 minutes. A crosslinking agent was added and stirred for 30 minutes to mix evenly. Finally, when the temperature dropped to 39°C, a latent catalytic system was added, stirred for 25 minutes, and then vacuum degassed for 50 minutes. The mixture was then sealed and packaged to obtain a single-component latent repair material.

[0097] Indoor construction simulation was conducted. To simulate underwater concrete structure repair, concrete test blocks with dimensions of 500mm×500mm×200mm were used. They were cast using C40 marine concrete and cured for 28 days. Then, the test blocks were completely immersed in artificial seawater for 90 days to bring them to a water saturation state with a moisture content close to 20%.

[0098] The construction method for repairing underwater concrete structures in this embodiment includes the following steps: Step 1: Substrate surface treatment: Divers carry underwater polishing tools to remove surface deposits. The surface roughness of the cleaned substrate is Ra18μm. The substrate has been immersed in water for a long time, and the water content is close to saturation at about 20%, with a pH value of 9.8.

[0099] Step Two: Material Application and Installation: Divers apply 12mm thick adhesive tape made of repair material to the underwater concrete surface, pressing it down with specialized underwater tools to apply pressure of approximately 0.3MPa. A specialized underwater anchoring system is used for fixation, with anchors spaced 220mm apart.

[0100] Step 3: Curing and Maintenance: The material is cured in an underwater environment at approximately 15°C and 100% relative humidity. Due to the low underwater temperature, the curing process is relatively slow, reaching the design strength requirements after 28 days.

[0101] Step 4: Quality Inspection: On the 28th day after the repair is completed, underwater quality inspection will be carried out with the assistance of divers.

[0102] The test results are as follows: storage stability > 12 months, initial solidification time 4.5h, 28-day bond strength 2.6MPa, no delamination or cracks found in underwater visual inspection; elongation at break 185%, 90-day chloride ion penetration depth 3.5mm, and bond strength retention rate 91% after 30 cycles.

[0103] Comparative Example 1 The difference between this comparative example and Example 2 is that the amount of hydroxyl-terminated polydimethylsiloxane used is 180 parts (higher than the upper limit specified in the claims), while the other components and preparation methods are the same as in Example 2.

[0104] The repair material of this comparative example, by weight, includes the following components: 180 parts of hydroxyl-terminated polydimethylsiloxane, 30 parts of butyl rubber, 40 parts of sulfoaluminate cement, 8 parts of crosslinking agent, 3 parts of latent catalytic system, 5 parts of tackifying resin, and 40 parts of filler.

[0105] Performance test results: Storage stability > 12 months, initial curing time 6.5h; Due to excessive use of hydroxyl-terminated polydimethylsiloxane, the material is too soft and lacks strength. The 28-day bond strength is only 1.5MPa, the elongation at break is 250%, the chloride ion penetration depth at 90 days is 6.5mm, and the bond strength retention rate after 30 cycles is 70%, which does not meet the engineering requirements; The material is prone to sagging and deformation when applied to vertical surfaces, resulting in poor workability; After curing, the material is too soft and prone to permanent deformation under external forces; The cost increases significantly by about 30%, making it uneconomical.

[0106] Comparative Example 2 The difference between this comparative example and Example 2 is that the amount of butyl rubber used is 10 parts, while the other components and preparation methods are the same as in Example 2.

[0107] Performance test results: Storage stability > 12 months, initial set time 8.0 h; elongation at break 160%, chloride ion penetration depth 5.5 mm after 90 days, and bond strength retention rate 78% after 30 cycles. Due to insufficient butyl rubber content, the initial tack of the material was significantly insufficient, and effective rapid positioning could not be achieved within 6 hours after construction; when constructing in tidal zones, the material was not fully fixed before the tide rose, and some material was washed away by seawater; when constructing on vertical surfaces, the material experienced significant creep and slippage, requiring more mechanical anchoring measures; the bond strength decreased to 1.9 MPa; the airtightness and drainage effect of the material weakened, and the bonding effect at wet interfaces decreased.

[0108] Comparative Example 3 The difference between this comparative example and Example 2 is that the amount of sulfoaluminate cement used is 20 parts, while the other components and preparation methods are the same as in Example 2.

[0109] Performance test results: Storage stability > 12 months, initial solidification time 5.5h. Due to insufficient sulfoaluminate cement content, the rigid skeleton of the material is not fully formed, resulting in severely insufficient mechanical strength. The 28-day bond strength is only 1.4MPa, far below the engineering requirements. The material is prone to deformation under external force. The elongation at break is 180%, the chloride ion penetration depth at 90 days is 6.8mm, and the bond strength retention rate after 30 cycles is 68%. The mechanical anchoring force is insufficient, and it is prone to detachment under wave impact. The compressive strength is low and cannot withstand normal use loads.

[0110] Comparative Example 4 The difference between this comparative example and Example 2 is that no latent catalytic system was added; instead, 3 parts of dibutyltin dilaurate catalyst were directly added. The other components and preparation methods were the same as in Example 2.

[0111] The repair material of this comparative example, by weight, includes the following components: 120 parts of hydroxyl-terminated polydimethylsiloxane, 30 parts of butyl rubber, 40 parts of sulfoaluminate cement, 8 parts of crosslinking agent, 5 parts of tackifying resin, 40 parts of filler, and 3 parts of dibutyltin dilaurate catalyst.

[0112] Performance test results: According to the accelerated aging test results at 50℃, after 7 days of accelerated aging at 50℃ (equivalent to 1.5 months of storage at 25℃), the viscosity change rate of this material reached 35%, and obvious gelation occurred, making further testing impossible. The material partially solidified in the packaging container; upon opening, it was found to be partially gelled and unusable. Even with freshly prepared material, the curing speed was uncontrollable, resulting in a short application window and poor application performance. Due to the rapid gelation, performance indicators such as bond strength, elongation at break, and chloride ion penetration depth could not be tested.

[0113] Comparative Example 5 The difference between this comparative example and Example 2 is that the amount of the latent catalytic system used is 10 parts, while the other components and preparation methods are the same as in Example 2.

[0114] The repair material of this comparative example, by weight, comprises the following components: 120 parts of hydroxyl-terminated polydimethylsiloxane, 30 parts of butyl rubber, 40 parts of sulfoaluminate cement, 8 parts of crosslinking agent, 10 parts of latent catalytic system, 5 parts of tackifying resin, and 40 parts of filler.

[0115] Performance test results: Storage stability > 12 months; 28-day bond strength 2.2 MPa; elongation at break 140%; 90-day chloride ion penetration depth 4.5 mm; bond strength retention rate 85% after 30 cycles. Due to excessive use of the latent catalyst system, although storage stability was good, the curing speed after application was too fast, with the initial curing time shortened to 2 hours. This short application window is unfavorable for large-area application and surface leveling. The excessively rapid curing led to stress concentration within the material, resulting in shrinkage cracks on the cured surface. Catalyst costs increased significantly, resulting in poor economic efficiency. Some incompletely complexed catalysts may cause unstable material performance.

[0116] Comparative Example 6 The difference between this comparative example and Example 2 is that no tackifying resin was added, while the other components and preparation methods are the same as in Example 2.

[0117] The repair material of this comparative example, by weight, includes the following components: 120 parts of hydroxyl-terminated polydimethylsiloxane, 30 parts of butyl rubber, 40 parts of sulfoaluminate cement, 8 parts of crosslinking agent, 3 parts of latent catalytic system, and 40 parts of filler.

[0118] Performance test results: Storage stability > 12 months, initial solidification time 1.5h; elongation at break 165%, chloride ion penetration depth 5.8mm after 90 days, and bond strength retention rate 76% after 30 cycles.

[0119] Due to the lack of tackifying resin, the material's adhesion and cohesive strength are significantly reduced; the adhesion between the material and the substrate is insufficient in the early stages of construction, making it prone to slipping when working on vertical surfaces; the initial tack of butyl rubber cannot be fully utilized, resulting in poor rapid positioning; the bonding strength drops to 1.8 MPa; and the material is prone to detachment under the scouring action of seawater when working in tidal zones.

[0120] Comparative Example 7 The difference between this comparative example and Example 2 is that the amount of crosslinking agent used is 3 parts, while the other components and preparation methods are the same as in Example 2.

[0121] Performance test results: Storage stability > 12 months, initial curing time 8.5h, elongation at break 195%, chloride ion penetration depth 7.5mm after 90 days, and bond strength retention rate 60% after 30 cycles. Due to insufficient crosslinking agent, the crosslinking density of the silicone rubber is low, curing is incomplete, the material is too soft, and the strength is severely insufficient, with a bond strength of only 1.3MPa after 28 days; the material is prone to softening and deformation at high temperatures; it has poor solvent resistance; long-term performance is unstable, and swelling occurs after long-term immersion in seawater.

[0122] Comparative Example 8 The difference between this comparative example and Example 2 is that the amount of filler used is 10 parts, while the other components and preparation methods are the same as in Example 2.

[0123] Performance test results: Storage stability > 12 months, initial curing time 5.5h, 28-day bond strength 2.0MPa; elongation at break 200%, 90-day chloride ion penetration depth 5.5mm, bond strength retention rate 80% after 30 cycles. However, due to insufficient filler content, material cost is too high, resulting in poor economic efficiency; dimensional stability of the material decreases, curing shrinkage is large; rheological properties are poor, making it prone to sagging during construction.

[0124] Comparative Example 9 The repair material in this comparative example is the same as that in Example 2, except that ordinary silicate cement 42.5R is used instead of sulfoaluminate cement.

[0125] Performance test results: Storage stability > 12 months, initial setting time 8 hours, elongation at break 175%, chloride ion penetration depth 6.8 mm after 90 days, and bond strength retention rate 72% after 30 cycles. Because ordinary Portland cement has a long initial setting time (approximately 2-3 hours), much slower than sulfoaluminate cement, the curing process is delayed, and the later curing stage is significantly prolonged. If construction is carried out in tidal zones, the material cannot form sufficient structural strength before the tide rises, making it easily washed away or eroded by seawater. Ordinary Portland cement has low early strength, with a 7-day bond strength of only 1.0 MPa and a 28-day bond strength of 1.5 MPa, failing to meet the requirements for rapid repair. Its synergistic effect with silicone rubber is poor, and the staged curing mechanism is not obvious.

[0126] Comparative Example 10 This comparative example uses the same repair material as Example 2, but the substrate surface was over-dried before construction, reducing the surface moisture content of the substrate to 2%.

[0127] Performance test results: Storage stability > 12 months, initial curing time 4.5h; elongation at break 182%, chloride ion penetration depth 3.0mm after 90 days, and bond strength retention rate 90% after 30 cycles. Although the material can still be applied and cured normally, and the bond strength reaches 2.4MPa after 28 days, it loses the technical advantage of wet interface application; to achieve the drying requirements, compressed air drying and other measures are required, significantly increasing the construction cost; in environments such as tidal zones and underwater areas, it is difficult to achieve such a low moisture content on the substrate surface, resulting in poor practical operability; although this comparative example shows that excessive drying does not lead to performance degradation, it violates the technical characteristics of wet interface application of this invention.

[0128] Comparative Example 11 This comparative example uses the same repair material as Example 2, but the surface moisture content of the substrate is 25% during construction, and there is an obvious water accumulation layer on the substrate surface.

[0129] Performance test results: Storage stability > 12 months, initial curing time 6.5h, elongation at break 170%, chloride ion penetration depth 7.0mm after 90 days, and bond strength retention rate 70% after 30 cycles. Due to excessive moisture on the substrate surface, a thick interfacial water film formed, making it difficult for the material to effectively wet the substrate surface. Although butyl rubber has a certain drainage effect, it cannot completely eliminate excessive interfacial moisture. The bond strength decreased significantly to 1.6MPa after 28 days, with poor bonding in some areas. The presence of the interfacial water film affected the chemical bonding and mechanical anchoring between the material and the substrate. During the curing process, interfacial moisture interfered with the cement hydration reaction, resulting in insufficient interfacial strength.

[0130] In the test results, except for the repair material of Comparative Example 7, which had a storage stability of 3 months, the repair materials of other examples and comparative examples all had a storage stability of more than 12 months. The other test results are summarized in Table 1. The units of data are indicated after the heading symbol " / " in Table 1. Storage stability is determined by whether the viscosity of the material is within acceptable limits after accelerated aging at 50°C for 56 days (equivalent to 12 months of storage at room temperature of 25°C).

[0131] Table 1. Test results of repair materials in the examples and comparative examples.

[0132] It can be seen from the above table: The repair materials in Examples 1-5 all exhibited excellent comprehensive performance, with storage stability exceeding 12 months, initial curing time within the range of 3-6 hours, 28-day bond strength exceeding 2.0 MPa, elongation at break exceeding 150%, chloride ion penetration depth controlled within 5 mm, and bond strength retention rate exceeding 88% after 30 seawater immersion-drying cycles, fully meeting the engineering requirements for wet interface repair of marine concrete structures.

[0133] Example 3 uses a higher ratio, resulting in the best performance indicators, making it particularly suitable for harsh marine environments and high-performance applications. Example 1 uses a lower ratio, which, although slightly lower in performance, still meets engineering requirements and has a relatively lower cost, making it suitable for general marine environment repairs.

[0134] Comparative Example 1, due to excessive use of hydroxyl-terminated polydimethylsiloxane, had a high elongation at break but severely insufficient strength, only 1.5 MPa, and poor workability and high cost.

[0135] In Comparative Example 2, due to insufficient butyl rubber, the initial curing time was extended to 8 hours, resulting in insufficient rapid positioning capability, which was not conducive to construction in tidal zones.

[0136] Comparative Example 3 had a bond strength of only 1.4 MPa due to insufficient sulfoaluminate cement content, which was far below the engineering requirements and the mechanical strength was seriously insufficient.

[0137] Comparative Example 4, lacking a latent catalytic system, had a storage stability of only 3 months. The material solidified during storage and could not be used normally.

[0138] Comparative Example 5 had an excessive amount of latent catalyst system and a short initial solidification time of only 2 hours, resulting in a short construction time window that was not conducive to large-scale construction.

[0139] Comparative Example 6, due to the lack of tackifying resin, had a prolonged initial curing time, insufficient rapid positioning ability, and decreased bonding strength.

[0140] Comparative Examples 7 and 8 show that the amount of crosslinking agent and filler used needs to be properly controlled.

[0141] Comparative Example 9 shows that sulfoaluminate cement is crucial for achieving a phased curing mechanism, while ordinary silicate cement, due to its long initial setting time and low early strength, cannot meet the requirements for rapid repair.

[0142] Although Comparative Example 10 has good performance, it loses the technical advantage of wet interface construction, has high construction costs, and has limited practical application value.

[0143] Comparative Example 11 shows that excessive moisture content on the substrate surface can seriously affect the bonding strength, indicating that although the material can be applied at a wet interface, the surface moisture still needs to be controlled within an appropriate range.

[0144] Application Example 1 This application example uses the same repair material formulation as in Example 2, and performs differentiated construction for three different marine environmental zones: atmospheric zone, splash zone, and tidal zone. Construction in atmospheric zones: The substrate surface moisture content is 5%, the repair material thickness is 4mm, and the bonding strength reaches 2.3MPa after 7 days of curing.

[0145] Construction in the splash zone: The substrate surface moisture content is 10%, the repair material thickness is 6mm, and it is frequently exposed to splashing waves. After 10 days of curing, the bonding strength reaches 2.4MPa.

[0146] Construction in tidal zones: The substrate surface moisture content is 15%, the repair material thickness is 8mm, and construction begins 2 hours before low tide. After 14 days of tidal cycle curing, the bonding strength reaches 2.7MPa.

[0147] After six months of natural environmental exposure testing following repair, the bond strength retention rates of the three areas were 95%, 92%, and 90%, respectively, all demonstrating good durability.

[0148] Table 2. Accelerated aging test results of the examples and comparative examples (stored at 50°C)

[0149] Table 2 shows that the viscosity change rate after 56 days of accelerated aging at 50℃ in Examples 1-5 was ≤15%, with no gelation or phase separation, indicating good storage stability, equivalent to more than 12 months of storage at room temperature (25℃). Comparative Example 4 (without a latent catalyst system, using dibutyltin dilaurate catalyst directly): gelation occurred within 7 days under accelerated aging at 50℃, verifying the crucial role of the latent catalyst system in storage stability. Other comparative examples: Although the storage stability was satisfactory, due to the component ratio exceeding the scope of the claims, other properties (such as bonding strength, flexibility, etc.) showed varying degrees of defects.

[0150] Table 3. Test results of the repair material in Application Example 1 after application in different scenarios.

[0151] The results in Table 3 demonstrate the effectiveness of the differentiated construction parameters in this application example, showing that the same material can achieve satisfactory repair results in different marine environments by adjusting the construction thickness and curing time.

[0152] Application Example 2 This embodiment uses the same repair material as in Embodiment 3, applied to a large-area repair project on a concrete platform at a wharf, with a repair area of ​​approximately 200m². 2 The construction method is carried out in sections and phases: The repair area was divided into 10 construction zones, each with an area of ​​approximately 20 square meters. 2 On the first day, construction in areas A and B will be completed. On the second day, construction in areas C and D will be completed, and so on. Adjacent construction areas will be spaced 24 hours apart, with an overlap width of 80mm.

[0153] On the 28th day after construction, quality inspections were conducted on each area. The bond strength ranged from 2.8 to 3.1 MPa, and the bond strength of the overlapping areas ranged from 2.7 to 2.9 MPa. The overall protective layer showed good continuity and consistency, and no cracking or delamination was found at the joints. Typical test results for a certain area were as follows: storage stability > 12 months, initial curing time 4.0 h, 28-day bond strength 2.9 MPa, elongation at break 198%, 90-day chloride ion penetration depth 2.6 mm, and bond strength retention rate 94% after 30 cycles.

[0154] This application example verifies the feasibility of the large-area zonal construction scheme. The performance of the overlapping area is consistent with that of the overall area, and no weak points are found at the joints.

[0155] In summary, the marine concrete structure wet interface repair material and construction method of the present invention achieves an organic unity of storage stability, wet interface construction capability, staged curing mechanism, excellent mechanical properties and durability by precisely controlling the proportion of each component. It provides an efficient and reliable technical solution for the maintenance and repair of marine concrete structures and has important engineering application value.

[0156] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A repair material for the wet interface of marine concrete structures, characterized in that: Including the following parts by weight of raw materials: Hydroxyl-terminated polydimethylsiloxane 100-150 parts, butyl rubber 20-60 parts, sulfoaluminate cement 30-80 parts, crosslinking agent 5-15 parts, latent catalytic system 2-8 parts, tackifying resin 3-10 parts, and filler 20-100 parts; The latent catalytic system is prepared by complexing an organotin catalyst and a chelating agent at a mass ratio of 1:0.5-1:2; the organotin catalyst is one or more of dibutyltin dilaurate and stannous octoate; the chelating agent is one or more of acetylacetone, sodium diacetylacetone, and salicylaldehyde acetylacetonate.

2. The marine concrete structure wet interface repair material according to claim 1, characterized in that: Including the following parts by weight of raw materials: Hydroxyl-terminated polydimethylsiloxane 120-140 parts, butyl rubber 30-50 parts, sulfoaluminate cement 40-60 parts, crosslinking agent 8-12 parts, latent catalytic system 3-6 parts, tackifying resin 5-8 parts, and filler 40-80 parts.

3. The marine concrete structure wet interface repair material according to claim 1, characterized in that: The viscosity of the hydroxyl-terminated polydimethylsiloxane is 5000-50000 mPa·s; the Mooney viscosity of the butyl rubber is 30-60; the crosslinking agent is one or more of tetraethyl orthosilicate, methyltrimethoxysilane, and vinyltrimethoxysilane; the tackifying resin is one or more of rosin-modified phenolic resin, terpene resin, and C5 petroleum resin; and the filler is one or more of calcium carbonate, talc, and silica fume.

4. The marine concrete structure wet interface repair material according to claim 1, characterized in that: The method for preparing the latent catalytic system is as follows: the organotin catalyst and the chelating agent are mixed under an inert atmosphere and stirred for 30-120 minutes to obtain a complex, which is the latent catalytic system.

5. The marine concrete structure wet interface repair material according to claim 1, characterized in that: The preparation method of the marine concrete structure wet interface repair material is as follows: hydroxyl-terminated polydimethylsiloxane, butyl rubber and tackifying resin are mixed evenly at 60-90℃ to form a base adhesive; then filler, sulfoaluminate cement and crosslinking agent are added in sequence and stirred evenly; finally, when the temperature drops below 40℃, a latent catalytic system is added, and after vacuum degassing, the mixture is sealed and packaged to obtain a single-component latent repair material.

6. A method for repairing the wet interface of a marine concrete structure, characterized in that: Using the marine concrete structure wet interface repair material as described in any one of claims 1 to 5, the steps include: Step 1: Clean the wet interface of the marine concrete structure to be repaired, removing marine organisms, loose concrete and oil stains attached to the surface, while keeping the wet interface moist. Step 2: Apply the marine concrete structure wet interface repair material to the wet interface to be repaired, press it to make full contact with the marine concrete structure wet interface repair material, and use mechanical anchors to assist in fixation. Step 3: Curing under environmental conditions of relative humidity 60%-95% and temperature 5-35℃; avoid external disturbance to the marine concrete structure wet interface repair material within 6 hours after construction.

7. The method for repairing the wet interface of a marine concrete structure according to claim 6, characterized in that: In step one, high-pressure water jets, wire brushes, or handheld power tools are used to remove the deposits on the surface of the wet interface to be repaired. After cleaning, the roughness Ra of the wet interface to be repaired is controlled at 6.3-25μm, the surface moisture content is controlled at 5%-20%, and the pH value is controlled within the range of 7-13. For severely rusted exposed steel bars, rust removal treatment is performed and anti-rust primer is applied.

8. The method for repairing the wet interface of a marine concrete structure according to claim 6, characterized in that: In step two, the repair material is made into a tape or sheet with a thickness of 2-10mm, or it is directly applied to the surface to be repaired with a thickness of 3-15mm; a pressure of 0.1-0.5MPa is applied when applying it.

9. The method for repairing the wet interface of a marine concrete structure according to claim 6, characterized in that: The aforementioned method for repairing the wet interface of marine concrete structures employs differentiated construction techniques for different marine environmental regions: In atmospheric and splash zones, the repair material thickness is 3-8mm, and the curing time is no less than 7 days; in tidal zones, the repair material thickness is 5-10mm, and the construction should begin 2-3 hours before low tide, with a curing time of no less than 14 days; in underwater zones, the repair material is made into sheets with a thickness of 8-15mm, and an underwater rapid application process is used, with the assistance of divers or underwater robots, with a curing time of no less than 21 days.

10. The method for repairing the wet interface of a marine concrete structure according to claim 6, characterized in that: For large-area repair work, a zoned and segmented construction method should be adopted; the area of ​​a single construction operation should be controlled within 10-50m². 2 The construction time interval between adjacent construction areas is 12-24 hours, and the overlap width is 50-100mm to ensure the continuity and consistency of the overall protective layer.

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