Corrosion-resistant and high-temperature-resistant concrete structure and preparation method thereof

Abstract

The invention discloses an anti-corrosion and high-temperature-resistant concrete structure and a preparation method thereof. According to the invention, by using the water reducing agent and the non-chlorine salt early strength agent, the fluidity of the concrete is improved, the construction is convenient, and meanwhile, the concrete can be rapidly hardened and the construction period is shortened by adding the early strength agent. In addition, the catalyst is added into water after uniform mixing, the curing process of the concrete can be accelerated through a specific preparation method, and the early strength and durability of the concrete are further improved. According to the construction method of the anti-corrosion and high-temperature-resistant concrete, the environmental erosion resistance of the concrete is improved, the mechanical property and the construction performance of the concrete are enhanced, and remarkable economic and social benefits are achieved. The successful application of the method provides an effective solution for long-term use of the concrete structure in acid-base corrosion and high-temperature environments, and has important practical application value.

Description

Technical Field

[0001] The invention belongs to the technical field of concrete structures, and in particular relates to an anti-corrosion and high-temperature resistant concrete structure and a preparation method thereof. Background Art

[0002] Concrete structure refers to building components made of concrete materials, such as columns, beams, slabs, walls, etc. Concrete structure is widely used in modern buildings. Its main advantages include high strength, good durability, strong fire resistance, and simple construction. The main characteristics of concrete structure include: High strength: Concrete has high compressive strength and tensile strength and can withstand large loads. Good durability: Concrete has good corrosion resistance, freeze-thaw resistance and impermeability, and can maintain the stability and safety of the structure for a long time. Strong fire resistance: Concrete has good fire resistance and can effectively isolate the spread of fire and ensure the safety of personnel. Simple construction: The construction process of concrete structure is relatively simple, including formwork making, concrete pouring, and maintenance. In short, concrete structure is a building component with the advantages of high strength, good durability, and strong fire resistance. With the continuous development of construction technology and the continuous improvement of people's requirements for building quality, concrete structure will play an increasingly important role in the construction industry.

[0003] However, common concrete structures are not treated with anti-corrosion treatment, which makes the overall corrosion resistance and high temperature resistance not strong enough, affecting the overall service life. Summary of the invention

[0004] The purpose of the present invention is to provide a corrosion-resistant and high-temperature-resistant concrete structure and a preparation method thereof in order to solve the above-mentioned problems.

[0005] The technical solution adopted by the present invention is as follows: an anti-corrosion and high temperature resistant concrete structure, the anti-corrosion and high temperature resistant concrete structure comprising:

[0006] 400-430 parts by weight of silicate sand;

[0007] 230-240 parts by weight of slag powder;

[0008] 50-65 parts by weight of powdered metakaolin;

[0009] 18-20 parts by weight of silane coupling agent emulsion;

[0010] 20-30 parts by weight of non-chloride salt early strength agent;

[0011] 20-40 parts by weight of water reducing agent;

[0012] 100-120 parts by weight of an anticorrosive agent;

[0013] 250-350 parts by weight of reinforcing fiber;

[0014] 430-450 parts by weight of water;

[0015] 30-50 parts by weight of curing agent.

[0016] In a preferred embodiment, the preparation method comprises the following steps:

[0017] S1: First, weigh the raw materials for preparing the anti-corrosion and high temperature resistant concrete structure:

[0018] 400-430 parts by weight of silicate sand;

[0019] 230-240 parts by weight of slag powder;

[0020] 50-65 parts by weight of powdered metakaolin;

[0021] 18-20 parts by weight of silane coupling agent emulsion;

[0022] 20-30 parts by weight of non-chloride salt early strength agent;

[0023] 20-40 parts by weight;

[0024] 100-120 parts by weight of an anticorrosive agent;

[0025] 250-350 parts by weight of reinforcing fiber;

[0026] 430-450 parts by weight of water;

[0027] 30-50 parts by weight of curing agent;

[0028] S2: preparing an anti-corrosion and high temperature resistant concrete structural skeleton, welding and fixing the steel skeleton of the anti-corrosion and high temperature resistant concrete structure, treating the surface with a NaOH solution, spraying a silane rust inhibitor on the surface, and finally making the steel skeleton after the rust prevention treatment, and placing it in a clean mold;

[0029] S3: Add the slag powder and water weighed in step S1 into a concrete mixer, stir until uniform, and then add 70-90% of the required water weight into the concrete mixer;

[0030] S4: mixing the silicate sand and the metakaolin evenly, adding the pre-dispersed reinforcing fiber through a vibrating screen under stirring, and then continuing to stir and mix;

[0031] S5: After the mixture in step S4 is evenly mixed, silane coupling agent emulsion, non-chloride salt early strength agent, curing agent and corrosion inhibitor are added, water is added after mixing evenly, and the mixture is mixed and stirred for 30 minutes, and then concrete for preparing trench cover is obtained;

[0032] S6: evenly loading the concrete obtained in step S5 into a mold with a steel bar skeleton installed, and after the material distribution is completed, closing the mold and prestressing the prestressed steel bar, with the tensioning force being 70-75% of the total tensile strength of the prestressed steel bar;

[0033] S7: performing centrifugal forming operation on the mold filled with concrete after prestressing until the concrete trench cover is formed, and finally curing the mold filled with concrete and steel skeleton at room temperature, wherein the curing temperature is 20-30° C. and the curing time is 24 hours;

[0034] S8: After the curing is completed, the prepared concrete trench cover is collected and preserved to obtain the acid and alkali corrosion resistant concrete trench cover, thus completing the entire preparation process of the anti-corrosion and high temperature resistant concrete structure.

[0035] In a preferred embodiment, in the step S1, the reinforcing fibers include: 70% to 80% by mass of hard reinforcing fibers and 15% to 25% by mass of soft tear-resistant fibers.

[0036] In a preferred embodiment, the hard reinforcing fiber is one or more combinations of carbon fiber, basalt fiber, aramid fiber, polypropylene fiber or polyvinyl alcohol fiber.

[0037] In a preferred embodiment, the soft tear-resistant fiber is a mixture of one or more of polylactic acid fiber, vinylon fiber, polyethylene fiber or polyacrylonitrile fiber.

[0038] In a preferred embodiment, in step S1, the preservative is one or a combination of sodium nitrate, potassium nitrate, potassium benzoate, potassium fluorosilicate, barium sulfate, silver nitrate, and lithium borate; and an air entraining agent is added at the same time, and the air entraining agent is one or a combination of sulfonated lignin, rosin resin extract, and alkyl glycoside.

[0039] In a preferred embodiment, in step S1, the water reducer is one or a combination of aliphatic, naphthalene-based water reducer or polycarboxylate water reducer.

[0040] In a preferred embodiment, in step S1, the non-chloride salt early strength agent is one or a combination of triisopropanolamine, magnesium nitrate, sodium nitrate, potassium sulfate, potassium thiosulfate.

[0041] In a preferred embodiment, in step S2, the surface of the steel skeleton is coated with a uniformly distributed anti-corrosion coating, wherein the anti-corrosion coating is a mesh protective film layer formed by coupling and cross-linking a silane rust inhibitor on the surface of the steel skeleton.

[0042] In a preferred embodiment, in step S5, a catalyst is added to the water added after mixing, and the catalyst is prepared by mixing dienyl palladium chloride (such as 1,5-cyclooctadiene palladium chloride), sodium borohydride and diethyl ether in a weight ratio of 5:1:2 in an inert gas atmosphere, reacting at room temperature for 24 hours, then filtering to remove the generated sodium borate, washing with heptane, and then recrystallizing in dichloromethane at -30°C.

[0043] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0044] 1. In the present invention, by using specific preservatives such as sodium nitrate, potassium nitrate, potassium benzoate, potassium fluorosilicate, barium sulfate, silver nitrate and lithium borate, the concrete structure can remain stable in an acid-base environment and is not susceptible to chemical erosion. Secondly, by coating the surface of the steel skeleton with a silane rust inhibitor, a uniformly distributed anti-corrosion coating is formed, which further improves the durability of the concrete structure. Reinforcement fibers are also used, including hard reinforcement fibers and soft tear-resistant fibers, to improve the tensile strength, flexural strength and toughness of the concrete. Hard reinforcement fibers include carbon fibers, basalt fibers, aramid fibers, polypropylene fibers and polyvinyl alcohol fibers, while soft tear-resistant fibers include polylactic acid fibers, vinylon fibers, polyethylene fibers and polyacrylonitrile fibers. The addition of these fibers significantly improves the mechanical properties of concrete, allowing it to withstand greater loads and harsher environmental conditions.

[0045] 2. In the present invention, during the construction process, by using a water reducing agent and a non-chloride salt early strength agent, the fluidity of the concrete is improved, which is convenient for construction. At the same time, the addition of the early strength agent allows the concrete to harden quickly and shorten the construction period. In addition, the catalyst added in the water added after mixing evenly can accelerate the curing process of the concrete through a specific preparation method, further improving its early strength and durability. This anti-corrosion and high temperature resistant concrete construction method not only improves the environmental erosion resistance of the concrete, but also enhances its mechanical properties and construction performance, and has significant economic and social benefits. The successful application of this method will provide an effective solution for the long-term use of concrete structures under acid and alkali corrosion and high temperature environments, and has important practical application value. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0047] Embodiment 1:

[0048] An anti-corrosion and high temperature resistant concrete structure, the anti-corrosion and high temperature resistant concrete structure comprising:

[0049] 400 parts by weight of silicate sand;

[0050] 230 parts by weight of slag powder;

[0051] 50 parts by weight of powdered metakaolin;

[0052] 18 parts by weight of silane coupling agent emulsion;

[0053] 20 parts by weight of non-chloride salt early strength agent;

[0054] 20 parts by weight of water reducing agent;

[0055] 100 parts by weight of anticorrosive agent;

[0056] 250 parts by weight of reinforcing fiber;

[0057] 430 parts by weight of water;

[0058] 30 parts by weight of curing agent.

[0059] The preparation method comprises the following steps:

[0060] S1: First, weigh the raw materials for preparing the anti-corrosion and high temperature resistant concrete structure:

[0061] 400 parts by weight of silicate sand;

[0062] 230 parts by weight of slag powder;

[0063] 50 parts by weight of powdered metakaolin;

[0064] 18 parts by weight of silane coupling agent emulsion;

[0065] 20 parts by weight of non-chloride salt early strength agent;

[0066] 20 parts by weight of water reducing agent;

[0067] 100 parts by weight of anticorrosive agent;

[0068] 250 parts by weight of reinforcing fiber;

[0069] 430 parts by weight of water;

[0070] 30 parts by weight of curing agent;

[0071] S2: preparing an anti-corrosion and high temperature resistant concrete structural skeleton, welding and fixing the steel skeleton of the anti-corrosion and high temperature resistant concrete structure, treating the surface with a NaOH solution, spraying a silane rust inhibitor on the surface, and finally making the steel skeleton after the rust prevention treatment, and placing it in a clean mold;

[0072] S3: Add the slag powder and water weighed in step S1 into a concrete mixer, stir until uniform, and then add 70-90% of the required water weight into the concrete mixer;

[0073] S4: mixing the silicate sand and the metakaolin evenly, adding the pre-dispersed reinforcing fiber through a vibrating screen under stirring, and then continuing to stir and mix;

[0074] S5: After the mixture in step S4 is evenly mixed, silane coupling agent emulsion, non-chloride salt early strength agent, curing agent and corrosion inhibitor are added, water is added after mixing evenly, and the mixture is mixed and stirred for 30 minutes, and then concrete for preparing trench cover is obtained;

[0075] S6: evenly loading the concrete obtained in step S5 into a mold with a steel bar skeleton installed, and after the material distribution is completed, closing the mold and prestressing the prestressed steel bar, with the tensioning force being 70-75% of the total tensile strength of the prestressed steel bar;

[0076] S7: performing centrifugal forming operation on the mold filled with concrete after prestressing until the concrete trench cover is formed, and finally curing the mold filled with concrete and steel skeleton at room temperature, wherein the curing temperature is 20-30° C. and the curing time is 24 hours;

[0077] S8: After the curing is completed, the prepared concrete trench cover is collected and preserved to obtain the acid and alkali corrosion resistant concrete trench cover, thus completing the entire preparation process of the anti-corrosion and high temperature resistant concrete structure.

[0078] In step S1, in step S1, the reinforcing fibers include: 70% to 80% by mass of hard reinforcing fibers and 15% to 25% by mass of soft tear-resistant fibers.

[0079] The hard reinforcing fiber is one or more combinations of carbon fiber, basalt fiber, aramid fiber, polypropylene fiber or polyvinyl alcohol fiber.

[0080] The soft tear-resistant fiber is a mixture of one or more of polylactic acid fiber, vinylon fiber, polyethylene fiber or polyacrylonitrile fiber.

[0081] In step S1, the preservative is one of sodium nitrate, potassium nitrate, potassium benzoate, potassium fluorosilicate, barium sulfate, silver nitrate, lithium borate or a combination thereof; and an air entraining agent is added at the same time, and the air entraining agent is one of sulfonated lignin, rosin resin extract, alkyl glycoside or a combination thereof.

[0082] In step S1, the water reducer is one of aliphatic water reducers, naphthalene water reducers and polycarboxylate water reducers, or a combination thereof.

[0083] In step S1, the non-chloride salt early strength agent is one of triisopropanolamine, magnesium nitrate, sodium nitrate, potassium sulfate, potassium thiosulfate or a combination thereof.

[0084] In step S2, the surface of the steel skeleton is coated with a uniformly distributed anti-corrosion coating, wherein the anti-corrosion coating is a mesh protective film layer formed by coupling and cross-linking a silane rust inhibitor on the surface of the steel skeleton.

[0085] In step S5, a catalyst is added to the water added after mixing evenly. The preparation method of the catalyst is: in an inert gas atmosphere, a dienyl palladium chloride (such as 1,5-cyclooctadiene palladium chloride), sodium borohydride and diethyl ether are mixed in a weight ratio of 5:1:2, and reacted at room temperature for 24 hours, and then filtered to remove the generated sodium borate, washed with heptane, and then recrystallized in dichloromethane at -30°C.

[0086] Then proceed with:

[0087] Acid resistance test:

[0088] Test method: The prepared concrete trench cover sample is immersed in a 5% sulfuric acid solution for 28 days.

[0089] Test results: The sample weight loss rate was 0.5% and the compressive strength retention rate was 95%, indicating that the concrete structure has excellent acid resistance.

[0090] Alkali resistance test:

[0091] Test method: Soak the sample in 5% sodium hydroxide solution for 28 days.

[0092] Test results: The sample weight loss rate was 0.8% and the compressive strength retention rate was 93%, indicating that the concrete structure has excellent alkali resistance.

[0093] Temperature resistance test:

[0094] Test method: The sample was kept at a high temperature of 200°C for 4 hours and then cooled at room temperature.

[0095] Test results: The sample had no cracks, the weight loss rate was 1.2%, and the compressive strength retention rate was 90%, indicating that the concrete structure has good stability and heat resistance in high temperature environment.

[0096] Anti-corrosion performance test:

[0097] Test method: The samples were immersed in a mixed solution of 5% sodium chloride and 1% sulfuric acid for 90 days to simulate the marine environment.

[0098] Test results: There is no rust on the sample surface, the weight loss rate is 1.0%, and the compressive strength retention rate is 92%, indicating that the concrete structure has excellent anti-corrosion performance in harsh corrosive environments.

[0099] Crack resistance test:

[0100] Test method: The sample was subjected to a freeze-thaw cycle test at -20°C for 50 cycles.

[0101] Test results: No cracks were produced in the samples, indicating that the concrete structure has good crack resistance and can adapt to temperature changes.

[0102] Mechanical properties test:

[0103] Test method: in accordance with the national standard GB / T 50081-2002 "Standard for test methods of mechanical properties of ordinary concrete".

[0104] Test results: The sample's 28-day compressive strength is 80MPa and its flexural strength is 6.5MPa, indicating that the concrete structure has very high mechanical properties.

[0105] From the above test data, it can be seen that the anti-corrosion and high-temperature resistant concrete structure has outstanding performance in acid and alkali corrosion resistance, high temperature resistance, corrosion resistance, crack resistance and mechanical properties, and is suitable for construction and infrastructure in harsh environments.

[0106] In the present invention, by using specific preservatives, such as sodium nitrate, potassium nitrate, potassium benzoate, potassium fluorosilicate, barium sulfate, silver nitrate and lithium borate, the concrete structure can remain stable under acid-base environment and is not susceptible to chemical erosion. Secondly, by applying silane rust inhibitor on the surface of the steel skeleton, a uniformly distributed anti-corrosion coating is formed, which further improves the durability of the concrete structure. Reinforcement fibers are also used, including hard reinforcement fibers and soft tear-resistant fibers, to improve the tensile strength, flexural strength and toughness of concrete. Hard reinforcement fibers include carbon fibers, basalt fibers, aramid fibers, polypropylene fibers and polyvinyl alcohol fibers, while soft tear-resistant fibers include polylactic acid fibers, vinylon fibers, polyethylene fibers and polyacrylonitrile fibers, etc. The addition of these fibers significantly improves the mechanical properties of concrete, allowing it to withstand greater loads and more severe environmental conditions.

[0107] In the present invention, in the construction process, by using a water reducer (such as aliphatic, naphthalene water reducer or polycarboxylate water reducer) and a non-chloride early strength agent (such as triisopropanolamine, magnesium nitrate, sodium nitrate, potassium sulfate, potassium thiosulfate, etc.), the fluidity of concrete is improved, which is convenient for construction, and the addition of the early strength agent enables concrete to harden quickly, shortening the construction period. In addition, the catalyst added in the water added after mixing evenly can accelerate the curing process of concrete by a specific preparation method, further improving its early strength and durability. The anticorrosive and high temperature resistant concrete construction method not only improves the environmental erosion resistance of concrete, but also enhances its mechanical properties and construction performance, and has significant economic and social benefits. The successful application of the method will provide an effective solution for the long-term use of concrete structures under acid-base corrosion and high temperature environments, and has important practical application value.

[0108] Embodiment two:

[0109] An anti-corrosion and high temperature resistant concrete structure, the anti-corrosion and high temperature resistant concrete structure comprising:

[0110] 430 parts by weight of silicate sand;

[0111] 240 parts by weight of slag powder;

[0112] 65 parts by weight of powdered metakaolin;

[0113] 20 parts by weight of silane coupling agent emulsion;

[0114] 30 parts by weight of non-chloride salt early strength agent;

[0115] 40 parts by weight of water reducing agent;

[0116] 120 parts by weight of an anticorrosive agent;

[0117] 350 parts by weight of reinforcing fiber;

[0118] 450 parts by weight of water;

[0119] 50 parts by weight of curing agent.

[0120] The preparation method comprises the following steps:

[0121] S1: First, weigh the raw materials for preparing the anti-corrosion and high temperature resistant concrete structure:

[0122] 430 parts by weight of silicate sand;

[0123] 240 parts by weight of slag powder;

[0124] 65 parts by weight of powdered metakaolin;

[0125] 20 parts by weight of silane coupling agent emulsion;

[0126] 30 parts by weight of non-chloride salt early strength agent;

[0127] 40 parts by weight of water reducing agent;

[0128] 120 parts by weight of an anticorrosive agent;

[0129] 350 parts by weight of reinforcing fiber;

[0130] 450 parts by weight of water;

[0131] 50 parts by weight of curing agent;

[0132] S2: preparing an anti-corrosion and high temperature resistant concrete structural skeleton, welding and fixing the steel skeleton of the anti-corrosion and high temperature resistant concrete structure, treating the surface with a NaOH solution, spraying a silane rust inhibitor on the surface, and finally making the steel skeleton after the rust prevention treatment, and placing it in a clean mold;

[0133] S3: Add the slag powder and water weighed in step S1 into a concrete mixer, stir until uniform, and then add 70-90% of the required water weight into the concrete mixer;

[0134] S4: mixing the silicate sand and the metakaolin evenly, adding the pre-dispersed reinforcing fiber through a vibrating screen under stirring, and then continuing to stir and mix;

[0135] S5: After the mixture in step S4 is evenly mixed, silane coupling agent emulsion, non-chloride salt early strength agent, curing agent and corrosion inhibitor are added, water is added after mixing evenly, and the mixture is mixed and stirred for 30 minutes, and then concrete for preparing trench cover is obtained;

[0136] S6: evenly loading the concrete obtained in step S5 into a mold with a steel bar skeleton installed, and after the material distribution is completed, closing the mold and prestressing the prestressed steel bar, with the tensioning force being 70-75% of the total tensile strength of the prestressed steel bar;

[0137] S7: performing centrifugal forming operation on the mold filled with concrete after prestressing until the concrete trench cover is formed, and finally curing the mold filled with concrete and steel skeleton at room temperature, wherein the curing temperature is 20-30° C. and the curing time is 24 hours;

[0138] S8: After the curing is completed, the prepared concrete trench cover is collected and preserved to obtain the acid and alkali corrosion resistant concrete trench cover, thus completing the entire preparation process of the anti-corrosion and high temperature resistant concrete structure.

[0139] In step S1, in step S1, the reinforcing fibers include: 70% to 80% by mass of hard reinforcing fibers and 15% to 25% by mass of soft tear-resistant fibers.

[0140] The hard reinforcing fiber is one or more combinations of carbon fiber, basalt fiber, aramid fiber, polypropylene fiber or polyvinyl alcohol fiber.

[0141] The soft tear-resistant fiber is a mixture of one or more of polylactic acid fiber, vinylon fiber, polyethylene fiber or polyacrylonitrile fiber.

[0142] In step S1, the preservative is one of sodium nitrate, potassium nitrate, potassium benzoate, potassium fluorosilicate, barium sulfate, silver nitrate, lithium borate or a combination thereof; and an air entraining agent is added at the same time, and the air entraining agent is one of sulfonated lignin, rosin resin extract, alkyl glycoside or a combination thereof.

[0143] In step S1, the water reducer is one of aliphatic, naphthalene-based water reducers and polycarboxylate water reducers, or a combination thereof.

[0144] In step S1, the non-chloride salt early strength agent is one of triisopropanolamine, magnesium nitrate, sodium nitrate, potassium sulfate, potassium thiosulfate or a combination thereof.

[0145] In step S2, the surface of the steel skeleton is coated with a uniformly distributed anti-corrosion coating, wherein the anti-corrosion coating is a mesh protective film layer formed by coupling and cross-linking a silane rust inhibitor on the surface of the steel skeleton.

[0146] In step S5, a catalyst is added to the water added after mixing evenly. The preparation method of the catalyst is: in an inert gas atmosphere, a dienyl palladium chloride (such as 1,5-cyclooctadiene palladium chloride), sodium borohydride and diethyl ether are mixed in a weight ratio of 5:1:2, and reacted at room temperature for 24 hours, and then filtered to remove the generated sodium borate, washed with heptane, and then recrystallized in dichloromethane at -30°C.

[0147] Then proceed with:

[0148] Acid resistance test:

[0149] Test method: The prepared concrete trench cover sample is immersed in a 5% sulfuric acid solution for 28 days.

[0150] Test results: The sample weight loss rate was 0.6% and the compressive strength retention rate was 94%, indicating that the concrete structure has excellent acid resistance.

[0151] Alkali resistance test:

[0152] Test method: Soak the sample in 5% sodium hydroxide solution for 28 days.

[0153] Test results: The sample weight loss rate was 0.7% and the compressive strength retention rate was 91%, indicating that the concrete structure has excellent alkali resistance.

[0154] Temperature resistance test:

[0155] Test method: The sample was kept at a high temperature of 200°C for 4 hours and then cooled at room temperature.

[0156] Test results: The sample had no cracks, the weight loss rate was 1.2%, and the compressive strength retention rate was 90%, indicating that the concrete structure has good stability and heat resistance in high temperature environment.

[0157] Anti-corrosion performance test:

[0158] Test method: The samples were immersed in a mixed solution of 5% sodium chloride and 1% sulfuric acid for 90 days to simulate the marine environment.

[0159] Test results: There is no rust on the sample surface, the weight loss rate is 1.1%, and the compressive strength retention rate is 93%, indicating that the concrete structure has excellent anti-corrosion performance in harsh corrosive environments.

[0160] Crack resistance test:

[0161] Test method: The sample was subjected to a freeze-thaw cycle test at -20°C for 50 cycles.

[0162] Test results: No cracks were produced in the samples, indicating that the concrete structure has good crack resistance and can adapt to temperature changes.

[0163] Mechanical properties test:

[0164] Test method: in accordance with the national standard GB / T 50081-2002 "Standard for test methods of mechanical properties of ordinary concrete".

[0165] Test results: The sample's 28-day compressive strength is 82MPa, and its flexural strength is 6.6MPa, indicating that the concrete structure has very high mechanical properties.

[0166] From the above test data, it can be seen that the anti-corrosion and high-temperature resistant concrete structure has outstanding performance in acid and alkali corrosion resistance, high temperature resistance, corrosion resistance, crack resistance and mechanical properties, and is suitable for construction and infrastructure in harsh environments.

[0167] In the present invention, by using specific preservatives, such as sodium nitrate, potassium nitrate, potassium benzoate, potassium fluorosilicate, barium sulfate, silver nitrate and lithium borate, the concrete structure can remain stable under acid-base environment and is not susceptible to chemical erosion. Secondly, by applying silane rust inhibitor on the surface of the steel skeleton, a uniformly distributed anti-corrosion coating is formed, which further improves the durability of the concrete structure. Reinforcement fibers are also used, including hard reinforcement fibers and soft tear-resistant fibers, to improve the tensile strength, flexural strength and toughness of concrete. Hard reinforcement fibers include carbon fibers, basalt fibers, aramid fibers, polypropylene fibers and polyvinyl alcohol fibers, while soft tear-resistant fibers include polylactic acid fibers, vinylon fibers, polyethylene fibers and polyacrylonitrile fibers, etc. The addition of these fibers significantly improves the mechanical properties of concrete, allowing it to withstand greater loads and more severe environmental conditions.

[0168] In the present invention, in the construction process, by using a water reducer (such as aliphatic, naphthalene water reducer or polycarboxylate water reducer) and a non-chloride early strength agent (such as triisopropanolamine, magnesium nitrate, sodium nitrate, potassium sulfate, potassium thiosulfate, etc.), the fluidity of concrete is improved, which is convenient for construction, and the addition of the early strength agent enables concrete to harden quickly and shorten the construction period. In addition, the catalyst added in the water added after mixing evenly can accelerate the curing process of concrete by a specific preparation method, and further improve its early strength and durability. The anticorrosive and high temperature resistant concrete construction method not only improves the environmental erosion resistance of concrete, but also enhances its mechanical properties and construction performance, and has significant economic and social benefits. The successful application of the method will provide an effective solution for the long-term use of concrete structures under acid-base corrosion and high temperature environments, and has important practical application value.

[0169] Embodiment three:

[0170] An anti-corrosion and high temperature resistant concrete structure, the anti-corrosion and high temperature resistant concrete structure comprising:

[0171] 425 parts by weight of silicate sand;

[0172] 230 parts by weight of slag powder;

[0173] 60 parts by weight of powdered metakaolin;

[0174] 19 parts by weight of silane coupling agent emulsion;

[0175] 30 parts by weight of non-chloride salt early strength agent;

[0176] 40 parts by weight of water reducing agent;

[0177] 120 parts by weight of an anticorrosive agent;

[0178] 350 parts by weight of reinforcing fiber;

[0179] 450 parts by weight of water;

[0180] 50 parts by weight of curing agent.

[0181] The preparation method comprises the following steps:

[0182] S1: First, weigh the raw materials for preparing the anti-corrosion and high temperature resistant concrete structure:

[0183] 430 parts by weight of silicate sand;

[0184] 240 parts by weight of slag powder;

[0185] 65 parts by weight of powdered metakaolin;

[0186] 20 parts by weight of silane coupling agent emulsion;

[0187] 30 parts by weight of non-chloride salt early strength agent;

[0188] 40 parts by weight of water reducing agent;

[0189] 120 parts by weight of an anticorrosive agent;

[0190] 350 parts by weight of reinforcing fiber;

[0191] 450 parts by weight of water;

[0192] 50 parts by weight of curing agent;

[0193] S2: preparing an anti-corrosion and high temperature resistant concrete structural skeleton, welding and fixing the steel skeleton of the anti-corrosion and high temperature resistant concrete structure, treating the surface with a NaOH solution, spraying a silane rust inhibitor on the surface, and finally making the steel skeleton after the rust prevention treatment, and placing it in a clean mold;

[0194] S3: Add the slag powder and water weighed in step S1 into a concrete mixer, stir until uniform, and then add 70-90% of the required water weight into the concrete mixer;

[0195] S4: mixing the silicate sand and the metakaolin evenly, adding the pre-dispersed reinforcing fiber through a vibrating screen under stirring, and then continuing to stir and mix;

[0196] S5: After the mixture in step S4 is evenly mixed, silane coupling agent emulsion, non-chloride salt early strength agent, curing agent and corrosion inhibitor are added, water is added after mixing evenly, and the mixture is mixed and stirred for 30 minutes, and then concrete for preparing trench cover is obtained;

[0197] S6: evenly loading the concrete obtained in step S5 into a mold with a steel bar skeleton installed, and after the material distribution is completed, closing the mold and prestressing the prestressed steel bar, with the tensioning force being 70-75% of the total tensile strength of the prestressed steel bar;

[0198] S7: performing centrifugal forming operation on the mold filled with concrete after prestressing until the concrete trench cover is formed, and finally curing the mold filled with concrete and steel skeleton at room temperature, wherein the curing temperature is 20-30° C. and the curing time is 24 hours;

[0199] S8: After the curing is completed, the prepared concrete trench cover is collected and preserved to obtain the acid and alkali corrosion resistant concrete trench cover, thus completing the entire preparation process of the anti-corrosion and high temperature resistant concrete structure.

[0200] In step S1, in step S1, the reinforcing fibers include: 70% to 80% by mass of hard reinforcing fibers and 15% to 25% by mass of soft tear-resistant fibers.

[0201] The hard reinforcing fiber is one or more combinations of carbon fiber, basalt fiber, aramid fiber, polypropylene fiber or polyvinyl alcohol fiber.

[0202] The soft tear-resistant fiber is a mixture of one or more of polylactic acid fiber, vinylon fiber, polyethylene fiber or polyacrylonitrile fiber.

[0203] In step S1, the preservative is one of sodium nitrate, potassium nitrate, potassium benzoate, potassium fluorosilicate, barium sulfate, silver nitrate, lithium borate or a combination thereof; and an air entraining agent is added at the same time, and the air entraining agent is one of sulfonated lignin, rosin resin extract, alkyl glycoside or a combination thereof.

[0204] In step S1, the water reducer is one of aliphatic, naphthalene-based water reducers and polycarboxylate water reducers, or a combination thereof.

[0205] In step S1, the non-chloride salt early strength agent is one of triisopropanolamine, magnesium nitrate, sodium nitrate, potassium sulfate, potassium thiosulfate or a combination thereof.

[0206] In step S2, the surface of the steel skeleton is coated with a uniformly distributed anti-corrosion coating, wherein the anti-corrosion coating is a mesh protective film layer formed by coupling and cross-linking a silane rust inhibitor on the surface of the steel skeleton.

[0207] In step S5, a catalyst is added to the water added after mixing evenly. The preparation method of the catalyst is: in an inert gas atmosphere, a dienyl palladium chloride (such as 1,5-cyclooctadiene palladium chloride), sodium borohydride and diethyl ether are mixed in a weight ratio of 5:1:2, and reacted at room temperature for 24 hours, and then filtered to remove the generated sodium borate, washed with heptane, and then recrystallized in dichloromethane at -30°C.

[0208] Then proceed with:

[0209] Acid resistance test:

[0210] Test method: The prepared concrete trench cover sample is immersed in a 5% sulfuric acid solution for 28 days.

[0211] Test results: The sample weight loss rate was 0.5% and the compressive strength retention rate was 93%, indicating that the concrete structure has excellent acid resistance.

[0212] Alkali resistance test:

[0213] Test method: Soak the sample in 5% sodium hydroxide solution for 28 days.

[0214] Test results: The sample weight loss rate was 0.6% and the compressive strength retention rate was 92%, indicating that the concrete structure has excellent alkali resistance.

[0215] Temperature resistance test:

[0216] Test method: The sample was kept at a high temperature of 200°C for 4 hours and then cooled at room temperature.

[0217] Test results: The sample had no cracks, the weight loss rate was 1.3%, and the compressive strength retention rate was 90%, indicating that the concrete structure has good stability and heat resistance in high temperature environment.

[0218] Anti-corrosion performance test:

[0219] Test method: The samples were immersed in a mixed solution of 5% sodium chloride and 1% sulfuric acid for 90 days to simulate the marine environment.

[0220] Test results: There is no rust on the sample surface, the weight loss rate is 1.0%, and the compressive strength retention rate is 93%, indicating that the concrete structure has excellent anti-corrosion performance in harsh corrosive environments.

[0221] Crack resistance test:

[0222] Test method: The sample was subjected to a freeze-thaw cycle test at -20°C for 50 cycles.

[0223] Test results: No cracks were produced in the samples, indicating that the concrete structure has good crack resistance and can adapt to temperature changes.

[0224] Mechanical properties test:

[0225] Test method: in accordance with the national standard GB / T 50081-2002 "Standard for test methods of mechanical properties of ordinary concrete".

[0226] Test results: The sample's 28-day compressive strength is 83MPa and its flexural strength is 6.4MPa, indicating that the concrete structure has very high mechanical properties.

[0227] From the above test data, it can be seen that the anti-corrosion and high-temperature resistant concrete structure has outstanding performance in acid and alkali corrosion resistance, high temperature resistance, corrosion resistance, crack resistance and mechanical properties, and is suitable for construction and infrastructure in harsh environments.

[0228] Comparative Example 1:

[0229] The conventional concrete formula does not contain slag powder, metakaolin, silane coupling agent emulsion, non-chloride salt early strength agent, corrosion inhibitor and reinforcing fiber.

[0230] Only basic ingredients such as Portland cement, sand, gravel and water are used.

[0231] According to the above experiments, the experimental results are shown in the following table:

[0232]

[0233]

[0234] It is thus known that in the present invention, by using specific preservatives, such as sodium nitrate, potassium nitrate, potassium benzoate, potassium fluorosilicate, barium sulfate, silver nitrate and lithium borate, the concrete structure can remain stable under acid-base conditions and is not susceptible to chemical erosion. Secondly, by applying a silane rust inhibitor on the surface of the steel skeleton, a uniformly distributed anti-corrosion coating is formed, which further improves the durability of the concrete structure. Reinforcement fibers are also used, including hard reinforcement fibers and soft tear-resistant fibers, to improve the tensile strength, flexural strength and toughness of concrete. Hard reinforcement fibers include carbon fibers, basalt fibers, aramid fibers, polypropylene fibers and polyvinyl alcohol fibers, while soft tear-resistant fibers include polylactic acid fibers, vinylon fibers, polyethylene fibers and polyacrylonitrile fibers, etc. The addition of these fibers significantly improves the mechanical properties of concrete, allowing it to withstand greater loads and more severe environmental conditions.

[0235] In the present invention, in the construction process, by using a water reducer (such as aliphatic, naphthalene water reducer or polycarboxylate water reducer) and a non-chloride early strength agent (such as triisopropanolamine, magnesium nitrate, sodium nitrate, potassium sulfate, potassium thiosulfate, etc.), the fluidity of concrete is improved, which is convenient for construction, and the addition of the early strength agent enables concrete to harden quickly and shorten the construction period. In addition, the catalyst added in the water added after mixing evenly can accelerate the curing process of concrete by a specific preparation method, and further improve its early strength and durability. The anticorrosive and high temperature resistant concrete construction method not only improves the environmental erosion resistance of concrete, but also enhances its mechanical properties and construction performance, and has significant economic and social benefits. The successful application of the method will provide an effective solution for the long-term use of concrete structures under acid-base corrosion and high temperature environments, and has important practical application value.

[0236] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0237] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A corrosion-resistant and high-temperature-resistant concrete structure, characterized in that: The anti-corrosion and high temperature resistant concrete structure comprises: 400-430 parts by weight of silicate sand; 230-240 parts by weight of slag powder; 50-65 parts by weight of powdered metakaolin; 18-20 parts by weight of silane coupling agent emulsion; 20-30 parts by weight of non-chloride salt early strength agent; 20-40 parts by weight of water reducing agent; 100-120 parts by weight of an anticorrosive agent; 250-350 parts by weight of reinforcing fiber; 430-450 parts by weight of water; 30-50 parts by weight of curing agent.

2. The method for preparing a corrosion-resistant and high-temperature-resistant concrete structure according to claim 1, characterized in that: The preparation method comprises the following steps: S1: First, weigh the raw materials for preparing the anti-corrosion and high temperature resistant concrete structure: 400-430 parts by weight of silicate sand; 230-240 parts by weight of slag powder; 50-65 parts by weight of powdered metakaolin; 18-20 parts by weight of silane coupling agent emulsion; 20-30 parts by weight of non-chloride salt early strength agent; 20-40 parts by weight; 100-120 parts by weight of an anticorrosive agent; 250-350 parts by weight of reinforcing fiber; 430-450 parts by weight of water; 30-50 parts by weight of curing agent; S2: preparing an anti-corrosion and high temperature resistant concrete structural skeleton, welding and fixing the steel skeleton of the anti-corrosion and high temperature resistant concrete structure, treating the surface with a NaOH solution, spraying a silane rust inhibitor on the surface, and finally making the steel skeleton after the rust prevention treatment, and placing it in a clean mold; S3: Add the slag powder and water weighed in step S1 into a concrete mixer, stir until uniform, and then add 70-90% of the required water weight into the concrete mixer; S4: mixing the silicate sand and the metakaolin evenly, adding the pre-dispersed reinforcing fiber through a vibrating screen under stirring, and then continuing to stir and mix; S5: After the mixture in step S4 is evenly mixed, silane coupling agent emulsion, non-chloride salt early strength agent, curing agent and corrosion inhibitor are added, water is added after mixing evenly, and the mixture is mixed and stirred for 30 minutes, and then concrete for preparing trench cover is obtained; S6: evenly loading the concrete obtained in step S5 into a mold with a steel bar skeleton installed, and after the material distribution is completed, closing the mold and prestressing the prestressed steel bar, with the tensioning force being 70-75% of the total tensile strength of the prestressed steel bar; S7: performing centrifugal forming operation on the mold filled with concrete after prestressing until the concrete trench cover is formed, and finally curing the mold filled with concrete and steel skeleton at room temperature, wherein the curing temperature is 20-30° C. and the curing time is 24 hours; S8: After the curing is completed, the prepared concrete trench cover is collected and preserved to obtain the acid and alkali corrosion resistant concrete trench cover, thus completing the entire preparation process of the anti-corrosion and high temperature resistant concrete structure.

3. The method for preparing a corrosion-resistant and high-temperature-resistant concrete structure according to claim 1, characterized in that: In the step S1, the reinforcing fibers include: 70% to 80% by mass of hard reinforcing fibers and 15% to 25% by mass of soft tear-resistant fibers.

4. The method for preparing a corrosion-resistant and high-temperature-resistant concrete structure according to claim 3, characterized in that: The hard reinforcing fiber is one or more combinations of carbon fiber, basalt fiber, aramid fiber, polypropylene fiber or polyvinyl alcohol fiber.

5. The method for preparing a corrosion-resistant and high-temperature-resistant concrete structure according to claim 3, characterized in that: The soft tear-resistant fiber is a mixture of one or more of polylactic acid fiber, vinylon fiber, polyethylene fiber or polyacrylonitrile fiber.

6. The method for preparing a corrosion-resistant and high-temperature-resistant concrete structure according to claim 1, characterized in that: In step S1, the preservative is one of sodium nitrate, potassium nitrate, potassium benzoate, potassium fluorosilicate, barium sulfate, silver nitrate, lithium borate or a combination thereof; and an air entraining agent is added at the same time, and the air entraining agent is one of sulfonated lignin, rosin resin extract, alkyl glycoside or a combination thereof.

7. The method for preparing a corrosion-resistant and high-temperature-resistant concrete structure according to claim 1, characterized in that: In the step S1, the water reducer is one of aliphatic water reducers, naphthalene water reducers and polycarboxylate water reducers or a combination thereof.

8. The method for preparing a corrosion-resistant and high-temperature-resistant concrete structure according to claim 1, characterized in that: In the step S1, the non-chloride salt early strength agent is one of triisopropanolamine, magnesium nitrate, sodium nitrate, potassium sulfate, potassium thiosulfate or a combination thereof.

9. The method for preparing a corrosion-resistant and high-temperature-resistant concrete structure according to claim 1, characterized in that: In the step S2, the surface of the steel skeleton is coated with a uniformly distributed anti-corrosion coating, wherein the anti-corrosion coating is a mesh protective film layer formed by coupling and cross-linking a silane rust inhibitor on the surface of the steel skeleton.

10. The method for preparing a corrosion-resistant and high-temperature-resistant concrete structure according to claim 1, characterized in that: In the step S5, a catalyst is added to the water added after mixing evenly. The catalyst is prepared by mixing dienylpalladium chloride, sodium borohydride and diethyl ether in a weight ratio of 5:1:2 in an inert gas atmosphere, reacting at room temperature for 24 hours, then filtering to remove the generated sodium borate, washing with heptane, and then recrystallizing in dichloromethane at -30°C.

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