Marine concrete self-repairing material, preparation method and application

Abstract

The invention discloses a marine concrete self-repairing material which is of a microcapsule structure and comprises a repairing core material and an environment triggering response wall material wrapping the repairing core material. In parts by weight, the weight ratio of the repairing core material to the environment triggering response wall material is (3-5): (1-2); the environment triggering response wall material is prepared from a water swelling material; the repairing core material comprises a material which generates an expansive hydration product when encountering water. When the concrete system has cracks, the environment-triggered response wall material absorbs water, swells and breaks; and water molecules enter the surface of the repairing core material to react to generate an expansive hydration product, so that the environment-triggered response wall material is further broken due to volume expansion of the repairing core material. After the repairing core material is released, an expansion reaction can be quickly generated, micro-cracks in the concrete are repaired in real time, and the penetration resistance of the concrete is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of concrete admixtures, and in particular relates to a self-repairing material for marine engineering concrete, a preparation method and uses thereof. Background Art

[0002] With the rapid development of marine engineering construction, concrete has been widely used in coastal ports, cross-sea bridges, docks, submarine tunnels, offshore drilling platforms, submarine cable laying and other engineering fields due to its advantages of high strength, low cost and good integrity. However, the marine environment is extremely complex, and concrete structures are subject to multiple coupling forms of damage such as sea breeze erosion, wave scouring, dry-wet cycles, and salt erosion, which seriously endanger the durability of concrete. Among them, the chloride ions and sulfate ions present in seawater can cause salt erosion and affect the service life of concrete. Chloride ions can diffuse and migrate in the pore channels of concrete, and when they reach the surface of the steel bars, they will damage the passivation film on the surface of the steel bars, causing the steel bars to rust and expand in volume, thereby causing the reinforced concrete structure to fail. In addition, sulfate ions can react with concrete hydration products to generate corrosion products such as calcium aluminate and gypsum, which affect the volume stability of concrete, easily cause concrete expansion and cracking, and reduce the durability of concrete structures. In addition, dry-wet cycles, freeze-thaw cycles, etc. accelerate the erosion and damage of salts to concrete structures. Therefore, solving the problem of salt erosion of marine concrete and improving the crack and corrosion resistance of concrete are of great significance to the development of marine engineering construction.

[0003] At present, the use of anti-corrosion agents is the simplest and most effective technical measure to improve the durability of marine engineering concrete. Anti-corrosion agents can improve the internal pore structure of concrete, increase the density of concrete, and greatly improve the impermeability of concrete. At present, mineral admixtures such as fly ash and slag are often added to increase the content of hydrated calcium silicate in cement-based materials to improve the density of concrete structures. In addition, admixtures can effectively improve the durability of concrete, use nanomaterials to fill and improve the concrete's ability to resist ion penetration, use hydrotalcite-like materials to improve the concrete's chloride ion curing ability, and use composite fiber toughening to improve the concrete's ability to resist cracking. However, in the marine environment, salt erosion lasts for a long period of time, and the risks of steel bar corrosion and expansion and calcium sulfonate expansion and cracking may require a long period of accumulation. Common mineral admixtures and admixtures mainly act in the early stage of cement hydration, and their ability to act is limited. Under long-term conditions, the cracks inside the concrete cannot be repaired in time, and it is difficult to achieve the improvement of the concrete's long-term anti-permeability ability. Summary of the invention

[0004] The purpose of the present invention is to solve the problem that the internal cracks of existing concrete cannot be repaired in time under long-term conditions, and it is difficult to improve the anti-penetration ability of concrete under long-term conditions.

[0005] The purpose of the present invention is to adopt the following technical solutions to achieve:

[0006] A self-repairing material for marine concrete, the self-repairing material is a microcapsule structure, comprising: a repair core material and an environment-triggered response wall material wrapped outside the repair core material; in parts by weight, the weight ratio of the repair core material to the environment-triggered response wall material is (3-5):(1-2); the environment-triggered response wall material is made of a material that swells when in contact with water; the repair core material comprises a material that generates an expansive hydration product when in contact with water.

[0007] Preferably, the repair core material comprises the following components in parts by weight: 10 to 20 parts by weight of modified resin, 5 to 10 parts by weight of quicklime, 5 to 10 parts by weight of anhydrous calcium sulphoaluminate, and 5 to 8 parts by weight of polypropylene fiber;

[0008] Preferably, the environmentally triggered responsive wall material is obtained by crosslinking and modification of the following components in parts by weight: 10 to 15 parts by weight of polyacrylic acid, 10 to 15 parts by weight of polyvinyl alcohol, 1 to 2 parts by weight of an organosilicon defoaming agent, and 2 to 3 parts by weight of a silane coupling agent.

[0009] Preferably, the modified resin is prepared by adding 10 to 20 parts by weight of stearic acid to 15 to 30 parts by weight of epoxy resin.

[0010] Based on the same inventive concept, the present invention also provides a preparation method for preparing a marine concrete self-repairing material as described above, the preparation method comprising the following steps:

[0011] S1. Preparation of repair core material;

[0012] S2. Preparation of environmentally triggered responsive wall materials;

[0013] S3. Under heating and stirring conditions, 80 to 100 parts by weight of the repair core material for self-repair of concrete microcracks are slowly added to 30 to 50 parts by weight of the environmentally triggered response wall material, and stirring is continued for 1 to 2 hours. After filtering and washing, vacuum drying is performed for 24 to 48 hours to obtain the marine engineering concrete self-repairing material.

[0014] Preferably, the preparation of the repair core material includes: taking 10 to 20 parts by weight of modified resin, mixing it evenly with 5 to 10 parts by weight of quicklime, 5 to 10 parts by weight of anhydrous calcium sulphoaluminate, and 5 to 8 parts by weight of polypropylene fiber, and then grinding and sieving to obtain the repair core material.

[0015] Preferably, the particle size of the repair core material after grinding and sieving is 45 to 80 μm.

[0016] Preferably, the preparation method of the modified resin comprises the following steps: adding 10 to 20 parts by weight of stearic acid to 15 to 30 parts by weight of epoxy resin, heating for 5 to 10 minutes, and vacuum drying at 50 to 60° C. for 24 to 48 hours to obtain the modified resin.

[0017] Preferably, the preparation of the environmentally triggered responsive wall material comprises: adding 10 to 15 parts by weight of polyvinyl alcohol, 5 to 8 parts by weight of polyacrylic acid and 1 to 2 parts by weight of a silicone defoamer to 30 to 50 parts by weight of water, stirring at 300 to 500 rpm at 90 to 95° C. for 4 to 6 hours, then adding 2 to 3 parts by weight of a silane coupling agent, stirring at 200 to 400 rpm at 40 to 50° C. for 1 to 3 hours to obtain the environmentally triggered responsive wall material.

[0018] Preferably, the main agent of the organosilicon defoamer is composite polyether modified silicone oil, with a mass fraction of 40% to 50%.

[0019] Preferably, the silane coupling agent is one of KH151, KH570 and KH792.

[0020] Based on the same inventive concept, the present invention also provides a use of a marine concrete self-repairing material, wherein the marine concrete self-repairing material as described above is added to marine concrete for use, with the addition amount being 6% to 8% of the total amount of cementitious materials in the concrete.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention discloses a self-repairing material for marine concrete. The self-repairing material is a microcapsule structure, which includes: a repair core material and an environment-triggered response wall material wrapped outside the repair core material; in parts by weight, the weight ratio of the repair core material to the environment-triggered response wall material is (3-5): (1-2); the environment-triggered response wall material is made of a material that swells when in contact with water; the repair core material includes a material that generates an expansive hydration product when in contact with water. When cracks appear in the concrete system, the environment-triggered response wall material absorbs water, swells and ruptures; causing water molecules to enter the surface of the core material to react and generate expansive hydration products, causing the environment-triggered response wall material to further rupture due to the expansion of the repair core material volume. After the repair core material is released, an expansion reaction can occur quickly, the cracks can be repaired in real time, and the concrete's anti-penetration ability can be improved. The anti-corrosion self-repairing material for marine concrete proposed by the present invention is a microcapsule structure, which is applied to reinforced concrete, can respond to changes in the external environment in real time, and has a real-time anti-crack self-repair function for concrete microcracks. The problem that the internal cracks of existing concrete cannot be repaired in time under long-term conditions and it is difficult to improve the anti-penetration ability of concrete under long-term conditions is solved. DETAILED DESCRIPTION

[0023] The technical solution is further described below in conjunction with specific embodiments to help understand the content of the present invention.

[0024] Example 1

[0025] The present invention relates to an anti-corrosion self-repairing material for marine engineering concrete, with a particle size of 80 to 150 μm. The microcapsule structure of the material is composed of a concrete microcrack repairing core material and an environment-triggered response wall material. The weight ratio of the core material to the wall material is (3 to 5): (1 to 2), for example, 3:2, 3:1.5, 3:1, 4:1, 4:1.5, 4:2, 5:1, 5:1.5 or 5:2, including any ratio values ​​between the above ratios.

[0026] The core material comprises the following components and weight parts: 10-20 weight parts of modified resin, 5-10 weight parts of quicklime, 5-10 weight parts of anhydrous calcium sulphoaluminate, and 5-8 weight parts of polypropylene fiber;

[0027] The wall material is obtained by crosslinking and modification of the following components in parts by weight: 10 to 15 parts by weight of polyacrylic acid, 10 to 15 parts by weight of polyvinyl alcohol, 1 to 2 parts by weight of an organic silicon defoaming agent, and 2 to 3 parts by weight of a silane coupling agent.

[0028] According to the above scheme, the method for preparing an anti-corrosion self-repairing material for marine engineering concrete includes the following contents:

[0029] (1) Preparation method of concrete microcrack repair core material: 10 to 20 parts by weight of modified resin, 5 to 10 parts by weight of quicklime, 5 to 10 parts by weight of anhydrous calcium sulphoaluminate, and 5 to 8 parts by weight of polypropylene fiber are mixed evenly, and then ground and sieved to obtain a particle size of 45 to 80 μm.

[0030] (2) Preparation method of environmentally triggered responsive wall material: add 10 to 15 parts by weight of polyvinyl alcohol, 5 to 8 parts by weight of polyacrylic acid and 1 to 2 parts by weight of silicone defoaming agent to 30 to 50 parts by weight of water, stir at 300 to 500 rpm at 90 to 95°C for 4 to 6 hours, then add 2 to 3 parts by weight of silane coupling agent, stir at 200 to 400 rpm at 40 to 50°C for 1 to 3 hours to obtain environmentally triggered responsive wall material.

[0031] (3) The packaging method of the anti-corrosion self-repairing material for marine engineering concrete is as follows: 80 to 100 parts by weight of concrete microcrack repair core material are slowly added to 30 to 50 parts by weight of environment-triggered response wall material at a stirring speed of 300 to 500 rpm and a heating temperature of 40 to 60° C., stirred for 1 to 2 hours, filtered and washed, and then vacuum dried for 24 to 48 hours to obtain the obtained product.

[0032] The preparation method of the modified resin comprises the following steps: adding 10 to 20 parts by weight of stearic acid to 15 to 30 parts by weight of epoxy resin, heating for 5 to 10 minutes, and vacuum drying at 50 to 60° C. for 24 to 48 hours to obtain the modified resin;

[0033] The main agent of the organosilicon defoamer is composite polyether modified silicone oil, with a mass fraction of 40% to 50%; the silane coupling agent is one of KH151, KH570 and KH792.

[0034] The application of the anti-corrosion self-repairing material for marine engineering concrete is to be used in marine engineering concrete, and the dosage is 6% to 8% of the total amount of cementitious materials.

[0035] The anti-corrosion self-repairing material for marine engineering concrete is used in concrete at a dosage of 6% to 8% of the total amount of cementitious materials. Compared with a blank group, the compressive strength at the age of 90 days is increased by 25% to 35%, the water seepage height is reduced by 30% to 40%, the corrosion resistance coefficient can be increased by 20% to 25%, and the chloride ion diffusion coefficient is reduced by 40% to 50%.

[0036] The following is a specific embodiment of an anti-corrosion self-repairing material for marine engineering concrete of the present invention:

[0037] The median particle size of the anti-corrosion self-repairing material for marine engineering concrete is 80 μm, and its microcapsule structure consists of a repair core material for filling and repairing concrete microcracks and an environment-triggered response wall material coated on the surface of the repair core material. In parts by weight, the weight ratio of the repair core material to the environment-triggered response wall material is 3:1.

[0038] In this embodiment, the specific preparation method of the anti-corrosion self-repairing material for marine engineering concrete comprises the following steps:

[0039] (1) Preparation method of concrete microcrack repair core material: 10 parts by weight of modified resin is mixed evenly with 5 parts by weight of quicklime, 5 parts by weight of anhydrous calcium sulphoaluminate and 5 parts by weight of polypropylene fiber, and the mixture is ground and sieved to obtain a repair core material having a median particle size of 45 μm.

[0040] (2) Preparation method of environmentally triggered responsive wall material: 10 parts by weight of polyvinyl alcohol, 5 parts by weight of polyacrylic acid and 1 part by weight of silicone defoaming agent are added to 30 parts by weight of water, stirred at 300 rpm at 90°C for 4 hours, then 2 parts by weight of silane coupling agent are added, and stirred at 200 rpm at 40°C for 1 hour to obtain environmentally triggered responsive wall material.

[0041] (3) Packaging method of anti-corrosion self-repairing material for marine engineering concrete: 80 parts by weight of concrete microcrack repair core material are slowly added to 30 parts by weight of environment-triggered response wall material at a stirring speed of 300 rpm and a heating temperature of 40°C, stirred for 1 hour, filtered and washed, and then vacuum dried for 24 hours to obtain.

[0042] In this embodiment, the preparation method of the modified resin comprises the following steps: adding 10 parts by weight of stearic acid to 15 parts by weight of epoxy resin, heating for 5 minutes, and vacuum drying at 50° C. for 24 hours to obtain a modified resin;

[0043] In this embodiment, the main agent of the organosilicon defoamer is composite polyether modified silicone oil, with a mass fraction of 40%; the model of the silane coupling agent is KH151.

[0044] Compared with the prior art, the present invention has the following advantages:

[0045] The anti-corrosion self-repairing material for marine engineering concrete proposed in the present invention is a microcapsule structure, which is applied to reinforced concrete. It can respond to changes in the external environment in real time and has the function of real-time anti-crack self-repair of concrete microcracks. When cracks appear in the concrete system, the environmentally triggered response wall material will be gradually broken by three effects, releasing the repair core material. On the one hand, at the same time as the cracks are generated, the environmentally triggered response wall material is damaged and defects are generated; on the other hand, free water gathers around the microcracks, and the environmentally triggered response wall material slowly absorbs water, swells and breaks; on the third hand, the formation of cracks causes the capillary channels inside the concrete to expand, and the corrosion inhibitor generates osmotic pressure inside and outside, causing water molecules to enter the surface of the repair core material to react and generate expansive hydration products, causing the environmentally triggered response wall material to break due to the expansion of the repair core material volume. After the repair core material is released, an expansion reaction can occur quickly to repair the cracks in real time and improve the concrete's anti-penetration ability.

[0046] The present invention designs an environmentally triggered responsive wall material, which has obvious advantages such as good compatibility, high strength, and uniform film formation. A high-performance hydrosol material with a network cross-linked structure is obtained by cross-linking and grafting reaction of polyacrylic acid, polyvinyl alcohol, an organosilicon defoamer, and a silane coupling agent. Polyacrylic acid can undergo an esterification cross-linking reaction with polyvinyl alcohol to improve the water absorption and swelling of the material. The graft copolymerization modification of the material using a silane coupling agent can generate a network cross-linked structure and improve the film-forming performance of the material. The organosilicon defoamer can effectively improve the dispersion and uniformity of the environmentally triggered responsive wall material.

[0047] The present invention designs a repair core material for repairing concrete microcracks, which has the advantages of strong self-repairing ability, high crack resistance, and long sustainable action time. Modified resin, quicklime, anhydrous calcium sulfoaluminate, and polypropylene fiber are used as the main raw materials in combination, and have the effects of crack resistance, self-repair, and reinforcement. Quicklime and anhydrous calcium sulfoaluminate are used as expansion initiators, which can quickly realize water absorption reaction expansion and fill cracks and pores. At the same time, polypropylene fiber has stable chemical properties and can physically fill tiny pores to make up for the shortcomings of chemical reaction of expansion initiator to repair cracks. The addition of modified resin can play a water storage role and prevent quicklime and anhydrous calcium sulfoaluminate from absorbing water too quickly to affect the stability of the material structure. The modified resin is prepared by compounding stearic acid and epoxy resin, which can improve the toughness of the material and enhance the water absorption performance of the material.

[0048] The present invention proposes an anti-corrosion self-repairing material for marine engineering concrete, which uses anti-corrosion materials such as anti-crack expansion materials, anti-crack repair fibers, and self-repairing resins as main raw materials, prepares capsule structural materials through modification, assembly and other methods, and develops a high-impermeability material with real-time monitoring and repairing concrete cracks function, which can overcome the shortcomings of conventional anti-corrosion agents such as low controllability and insufficient late-action ability.

[0049] Example 2

[0050] The present invention relates to a marine engineering concrete anticorrosion agent with a particle size of 150 μm. The microcapsule structure of the agent consists of a repair core material for filling and repairing concrete microcracks and an environment-triggered response wall material coated on the surface of the repair core material. The weight ratio of the repair core material to the environment-triggered response wall material is 5:2.

[0051] In this embodiment, the method for preparing an anti-corrosion self-repairing material for marine engineering concrete includes the following preparation method:

[0052] (1) Preparation method of concrete microcrack repair core material: 20 parts by weight of modified resin is mixed evenly with 10 parts by weight of quicklime, 10 parts by weight of anhydrous calcium sulfoaluminate, and 8 parts by weight of polypropylene fiber, and the mixture is ground and sieved to obtain a repair core material having a median particle size of 80 μm.

[0053] (2) Preparation method of environmentally triggered responsive wall material: 15 parts by weight of polyvinyl alcohol, 8 parts by weight of polyacrylic acid and 2 parts by weight of silicone defoaming agent are added to 50 parts by weight of water, stirred at 500 rpm at 95°C for 6 hours, then 3 parts by weight of silane coupling agent are added, and stirred at 400 rpm at 50°C for 3 hours to obtain environmentally triggered responsive wall material.

[0054] (3) The packaging method of the anti-corrosion self-repairing material for marine engineering concrete is as follows: 100 parts by weight of concrete microcrack repair core material is slowly added to 50 parts by weight of environment-triggered response wall material at a stirring speed of 500 rpm and a heating temperature of 60°C, stirred for 2 hours, filtered and washed, and then vacuum dried for 48 hours to obtain.

[0055] In this embodiment, the preparation method of the anticorrosive self-repairing material for marine engineering concrete, the preparation method of the modified resin comprises the following steps: adding 20 parts by weight of stearic acid to 30 parts by weight of epoxy resin, heating for 10 minutes, and vacuum drying at 60° C. for 48 hours to obtain a modified resin;

[0056] In this embodiment, the main agent of the organosilicon defoamer is composite polyether modified silicone oil, with a mass fraction of 50%; the model of the silane coupling agent is KH792.

[0057] Example 3

[0058] The present invention relates to a marine engineering concrete anticorrosion agent with a particle size of 115 μm. The microcapsule structure of the agent consists of a repair core material for repairing concrete microcracks and an environment-triggered response wall material coated on the outside of the repair core material. The weight ratio of the repair core material to the environment-triggered response wall material is 4:1.

[0059] In this embodiment, the method for preparing an anti-corrosion self-repairing material for marine engineering concrete includes the following preparation method:

[0060] (1) Preparation method of concrete microcrack repair core material: 15 parts by weight of modified resin is mixed evenly with 7 parts by weight of quicklime, 8 parts by weight of anhydrous calcium sulfoaluminate, and 7 parts by weight of polypropylene fiber, and the mixture is ground and sieved to obtain a repair core material having a median particle size of 65 μm.

[0061] (2) Preparation method of environmentally triggered responsive wall material: 12 parts by weight of polyvinyl alcohol, 6 parts by weight of polyacrylic acid and 1 part by weight of silicone defoaming agent are added to 40 parts by weight of water, stirred at 500 rpm at 90°C for 5 hours, then 3 parts by weight of silane coupling agent are added, and stirred at 300 rpm at 45°C for 2 hours to obtain environmentally triggered responsive wall material.

[0062] (3) The packaging method of the anti-corrosion self-repairing material for marine engineering concrete is as follows: 90 parts by weight of concrete microcrack repair core material is slowly added to 40 parts by weight of environment-triggered response wall material at a stirring speed of 400 rpm and a heating temperature of 50°C, stirred for 2 hours, filtered and washed, and then vacuum dried for 36 hours to obtain the obtained product.

[0063] In this embodiment, the preparation method of the anticorrosive self-repairing material for marine engineering concrete, the preparation method of the modified resin comprises the following steps: adding 15 parts by weight of stearic acid to 25 parts by weight of epoxy resin, heating for 8 minutes, and vacuum drying at 55° C. for 36 hours to obtain a modified resin;

[0064] In this embodiment, the main agent of the organosilicon defoamer is composite polyether modified silicone oil, with a mass fraction of 45%; the model of the silane coupling agent is KH570.

[0065] Example 4

[0066] The present invention relates to a marine engineering concrete anticorrosion agent with a particle size of 95 μm. The microcapsule structure of the agent consists of a repair core material for filling and repairing concrete microcracks and an environment-triggered response wall material coated on the surface of the repair core material. The weight ratio of the repair core material to the environment-triggered response wall material is 3:2.

[0067] In this embodiment, the method for preparing an anti-corrosion self-repairing material for marine engineering concrete includes the following preparation method:

[0068] (1) Preparation method of concrete microcrack repair core material: 12 parts by weight of modified resin is mixed evenly with 6 parts by weight of quicklime, 9 parts by weight of anhydrous calcium sulphoaluminate and 7 parts by weight of polypropylene fiber, and the mixture is ground and sieved to obtain a repair core material having a median particle size of 55 μm.

[0069] (2) Preparation method of environmentally triggered responsive wall material: 12 parts by weight of polyvinyl alcohol, 6 parts by weight of polyacrylic acid and 2 parts by weight of silicone defoaming agent are added to 35 parts by weight of water, stirred at 300 rpm at 95°C for 6 hours, then 3 parts by weight of silane coupling agent are added, and stirred at 40°C at 400 rpm for 1 hour to obtain environmentally triggered responsive wall material.

[0070] (3) The packaging method of the anti-corrosion self-repairing material for marine engineering concrete is as follows: 85 parts by weight of concrete microcrack repair core material is slowly added to 35 parts by weight of environment-triggered response wall material at a stirring speed of 500 rpm and a heating temperature of 40°C, stirred for 1 hour, filtered and washed, and then vacuum dried for 48 hours to obtain.

[0071] In this embodiment, the preparation method of the anticorrosive self-repairing material for marine engineering concrete, the preparation method of the modified resin comprises the following steps: adding 12 parts by weight of stearic acid to 18 parts by weight of epoxy resin, heating for 8 minutes, and vacuum drying at 60° C. for 48 hours to obtain a modified resin;

[0072] In this embodiment, the main agent of the organosilicon defoamer is composite polyether modified silicone oil, with a mass fraction of 50%; the model of the silane coupling agent is KH151.

[0073] Example 5

[0074] The present invention relates to a marine engineering concrete anticorrosion agent with a particle size of 135 μm. The microcapsule structure of the agent consists of a repair core material for filling and repairing concrete microcracks and an environment-triggered response wall material coated on the surface of the repair core material. The weight ratio of the repair core material to the environment-triggered response wall material is 5:1.

[0075] In this embodiment, the method for preparing an anti-corrosion self-repairing material for marine engineering concrete includes the following preparation method:

[0076] (1) Preparation method of concrete microcrack repair core material: 18 parts by weight of modified resin is mixed evenly with 9 parts by weight of quicklime, 7 parts by weight of anhydrous calcium sulfoaluminate, and 6 parts by weight of polypropylene fiber, and the mixture is ground and sieved to obtain a repair core material having a median particle size of 75 μm.

[0077] (2) Preparation method of environmentally triggered responsive wall material: 14 parts by weight of polyvinyl alcohol, 7 parts by weight of polyacrylic acid and 2 parts by weight of silicone defoaming agent are added to 45 parts by weight of water, stirred at 500 rpm at 90°C for 4 hours, and then 2 parts by weight of silane coupling agent are added, and stirred at 200 rpm at 50°C for 3 hours to obtain environmentally triggered responsive wall material.

[0078] (3) The packaging method of the anti-corrosion self-repairing material for marine engineering concrete is as follows: 95 parts by weight of concrete microcrack repair core material is slowly added to 45 parts by weight of environment-triggered response wall material at a stirring speed of 300 rpm and a heating temperature of 60°C, stirred for 2 hours, filtered and washed, and then vacuum dried for 36 hours to obtain the obtained product.

[0079] In this embodiment, the preparation method of the anticorrosive self-repairing material for marine engineering concrete, the preparation method of the modified resin comprises the following steps: adding 18 parts by weight of stearic acid to 26 parts by weight of epoxy resin, heating for 7 minutes, and vacuum drying at 60° C. for 48 hours to obtain a modified resin;

[0080] In this embodiment, the main agent of the organosilicon defoamer is composite polyether modified silicone oil, with a mass fraction of 50%; the model of the silane coupling agent is KH792.

[0081] Application Examples

[0082] Embodiments 1-5 were applied to concrete, and the mechanical properties of concrete were evaluated with reference to GB50081 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete"; the water penetration resistance was evaluated with the water seepage height method according to GB / T 50082-2009 "Standard for Test Methods of Long-term Performance and Durability of Ordinary Concrete"; the corrosion resistance coefficient and chloride ion diffusion coefficient of concrete specimens were measured with reference to GB / T 50082-2009 "Standard for Test Methods of Long-term Performance and Durability of Ordinary Concrete" and JGJ / T 193-2009 "Standard for Inspection and Evaluation of Concrete Durability" to characterize the salt corrosion resistance of concrete specimens. Among them, the mix ratio of the prepared concrete is shown in Table 1, the compressive strength and penetration height ratio results are shown in Table 2, and the salt corrosion resistance test results are shown in Table 3.

[0083] Table 1

[0084]

[0085]

[0086] Table 2

[0087]

[0088] Table 3

[0089]

[0090] The test results in Table 2 show that the anticorrosive agents used in Examples 1-5 can improve the compressive strength and anti-permeability of concrete. Compared with the comparative example, the compressive strength of Examples 1-5 at 90 days of age was increased by 27.3%, 33.3%, 27.9%, 30.8% and 29.7% respectively; the water seepage height was reduced by 34.1%, 37.3%, 33.2%, 39.8% and 37.9% respectively.

[0091] The data in Table 3 show that compared with the comparative example, the addition of the anticorrosive agent prepared in Examples 1-5 can effectively improve the concrete's resistance to sulfate erosion and chloride ion erosion. In both examples, as the amount of the anticorrosive agent increases, the chloride ion curing effect is also significantly improved. Compared with the blank group, the 90d corrosion resistance coefficient of the concrete specimens of Examples 1-5 can be increased by 21.2%, 24.2%, 22.7%, 21.2% and 24.2% respectively; the 90d chloride ion diffusion coefficient is reduced by 43.6%, 46.2%, 46.2%, 43.6% and 46.2% respectively.

[0092] In summary, the anti-corrosion self-repairing material for marine engineering concrete described in the present invention can effectively repair microcracks inside the concrete, improve the concrete's anti-penetration ability, and thus significantly delay the oxidative corrosion of the internal steel structure. It can significantly improve the durability of marine engineering concrete under long-term conditions and extend its service life, which has huge economic and social benefits.

[0093] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention.

Claims

1. A marine concrete self-repairing material, characterized in that: The self-healing material is a microcapsule structure, which includes: a repair core material and an environmentally triggered response wall material wrapped around the outside of the repair core material; in terms of weight, the weight ratio of the repair core material to the environmentally triggered response wall material is (3-5): (1-2); the environmentally triggered response wall material is made of a material that swells when exposed to water; the repair core material includes a material that generates an expandable hydration product when exposed to water.

2. A marine concrete self-repairing material according to claim 1, characterized in that: The repair core material comprises the following components in parts by weight: 10 to 20 parts by weight of modified resin, 5 to 10 parts by weight of quicklime, 5 to 10 parts by weight of anhydrous calcium sulphoaluminate, and 5 to 8 parts by weight of polypropylene fiber.

3. A marine concrete self-repairing material according to claim 1, characterized in that: The environmentally triggered responsive wall material is obtained by crosslinking and modification of the following components in parts by weight: 10 to 15 parts by weight of polyacrylic acid, 10 to 15 parts by weight of polyvinyl alcohol, 1 to 2 parts by weight of an organosilicon defoaming agent, and 2 to 3 parts by weight of a silane coupling agent.

4. A marine concrete self-repairing material as claimed in claim 2, characterized in that: The modified resin is prepared by adding 10 to 20 parts by weight of stearic acid to 15 to 30 parts by weight of epoxy resin.

5. A preparation method, characterized in that: Used to prepare a marine concrete self-repairing material as claimed in any one of claims 1 to 4, the preparation method comprises the following steps: preparing repair core material; Preparation of environmentally triggered responsive wall materials; Under heating and stirring conditions, 80 to 100 parts by weight of the repair core material for self-repair of concrete microcracks are slowly added to 30 to 50 parts by weight of the environmentally triggered response wall material, and stirring is continued for 1 to 2 hours. The resultant is filtered, washed and dried to obtain the marine engineering concrete self-repair material.

6. A preparation method according to claim 5, characterized in that: The preparation of the repair core material comprises: taking 10 to 20 parts by weight of modified resin, mixing it evenly with 5 to 10 parts by weight of quicklime, 5 to 10 parts by weight of anhydrous calcium sulphoaluminate and 5 to 8 parts by weight of polypropylene fiber, and then grinding and sieving to obtain the repair core material.

7. A preparation method according to claim 6, characterized in that: The particle size of the repair core material after grinding and sieving is 45-80 μm.

8. A preparation method according to claim 6, characterized in that: The preparation method of the modified resin comprises the following steps: adding 10 to 20 parts by weight of stearic acid into 15 to 30 parts by weight of epoxy resin, heating for 5 to 10 minutes, and vacuum drying at 50 to 60° C. for 24 to 48 hours to obtain the modified resin.

9. A preparation method according to claim 5, characterized in that: The preparation of the environmentally triggered responsive wall material comprises: adding 10 to 15 parts by weight of polyvinyl alcohol, 5 to 8 parts by weight of polyacrylic acid and 1 to 2 parts by weight of an organosilicon defoamer to 30 to 50 parts by weight of water, stirring at 300 to 500 rpm for 4 to 6 hours at 90 to 95° C., then adding 2 to 3 parts by weight of a silane coupling agent, stirring at 200 to 400 rpm for 1 to 3 hours at 40 to 50° C., to obtain the environmentally triggered responsive wall material.

10. A preparation method according to claim 9, characterized in that: The main agent of the organosilicon defoamer is composite polyether modified silicone oil, with a mass fraction of 40% to 50%.

11. A preparation method according to claim 9, characterized in that: The silane coupling agent is one of KH151, KH570 and KH792.

12. A use of a marine concrete self-repairing material, characterized in that: The marine engineering concrete self-repairing material as claimed in any one of claims 1 to 4 is added to marine engineering concrete for use, and the amount thereof is 6% to 8% of the total amount of cementitious materials in the concrete.

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