Fireproof anti-corrosion concrete and preparation method thereof

Abstract

The invention discloses fire-resistant and corrosion-resistant concrete, which is characterized in that the material components for preparing the fire-resistant and corrosion-resistant concrete comprise the following components in parts by mass: 100 parts of cement, 10 parts of fly ash, 10 parts of slag powder, 10 parts of coarse aggregate, 10 parts of fine aggregate, 10 parts of fire-resistant fiber material, 10 parts of corrosion-resistant agent and 10 parts of water. 20 to 30 parts of fly ash; 10 to 15 parts of slag powder; 150 to 250 parts of fine aggregate; 300 to 450 parts of coarse aggregate; 10 to 20 parts of a refractory fiber material; 1-2 parts of a corrosion resistant agent; and 50 to 70 parts of water. Through combined use of the fly ash, the slag powder and the chloride control agent, the corrosion resistance of the concrete is effectively improved. According to the invention, the refractory fiber material is added in the concrete, and in order to fully mix the refractory fiber material with the concrete, the refractory fiber material is cut into 1.5-5cm thin strips, and the thin strips are gradually put into the concrete mortar and uniformly stirred, so that the refractory fiber material can effectively improve the residual strength of the concrete after being burnt; therefore, the concrete has very high fire resistance.

Description

Technical Field

[0001] The invention belongs to the field of concrete preparation, and in particular relates to a fire-resistant and corrosion-resistant concrete and a preparation method thereof. Background Art

[0002] With the continuous acceleration of industrialization, many important equipment and structures need to have fire resistance and corrosion resistance to ensure their safe operation and long-term use. Traditional concrete is easily damaged in high temperature and corrosive environments, so it is necessary to develop fire-resistant and corrosion-resistant concrete to meet engineering needs.

[0003] Take chemical plants as an example. Chemical plants usually store various chemicals, some of which are corrosive, such as acids, alkalis, and salts. If ordinary concrete materials are used for the inner wall of the storage tank, long-term exposure to corrosive chemical environments will cause corrosion, loosening, or even damage to the concrete surface, reducing the service life of the storage tank and causing safety hazards. Therefore, in this scenario, the use of corrosion-resistant concrete materials can effectively extend the service life of the storage tank and improve the safety of the equipment. Secondly, the concrete used for the storage tank also needs to take into account fire resistance. Once a fire occurs, it must be ensured that the storage tank still has a high load-bearing capacity at high temperatures.

[0004] For example, for offshore structures, sea sand structures and structures in saline-alkali areas, chlorides in sea sand or the surrounding environment have a strong corrosive effect on the steel bars in the concrete, reducing the alkalinity of the concrete, destroying the passivation film on the surface of the steel bars, causing the steel bars to rust and expand, further leading to cracking and peeling of the concrete protective layer, and the structural function and mechanical properties continue to deteriorate. Domestic and foreign statistics show that the economic losses caused by steel bar corrosion are very huge. If these buildings involve living, storing chemicals or have a need for fire protection, the concrete must have fire resistance on the basis of corrosion resistance.

[0005] At present, there is no concrete product on the market that has both corrosion resistance and fire resistance. For concrete structures that need to be corrosion-resistant and fire-resistant, corrosion-resistant coatings or fire-resistant coatings are usually coated on the outer surface of concrete components to make the concrete structures have corrosion resistance and fire resistance. However, the material cost, labor cost and subsequent maintenance cost of doing so are very high.

[0006] Therefore, there is an urgent need to improve the formula of concrete so that the concrete has both corrosion resistance and fire resistance. Summary of the invention

[0007] In order to overcome the problems mentioned in the background technology, the present invention provides a fire-resistant and corrosion-resistant concrete and a preparation method thereof.

[0008] In order to achieve the above technical objectives, the technical solution adopted by the present invention is: A fire-resistant and anti-corrosion concrete, wherein the material components for preparing the fire-resistant and anti-corrosion concrete include cement, fly ash, slag powder, coarse aggregate, fine aggregate, refractory fiber material, anti-corrosion agent and water, wherein the amount of each material component is as follows, in parts by mass: Cement: 100 parts; Fly ash: 20-30 parts; Slag powder: 10-15 parts; Fine aggregate: 150-250 parts; Coarse aggregate: 300-450 parts; Corrosion resistance agent: 1-2 parts; Refractory fiber material: 10-20 parts; Water: 50-70 parts.

[0009] Furthermore, the material components for preparing the fire-resistant and corrosion-resistant concrete also include a water reducing agent, and the amount of the water reducing agent is 0.7-1 part by mass.

[0010] Furthermore, the water reducing agent is SN-Ⅱ.

[0011] Furthermore, the coarse aggregate is ceramsite aggregate with a particle size of 5mm-20mm.

[0012] Furthermore, the fine aggregate is sand with a particle size of 0.15 mm to 5 mm.

[0013] Furthermore, the refractory fiber material is steel fiber or glass fiber or polypropylene fiber or polyethylene fiber, and the corrosion resistant agent is a chloride control agent.

[0014] Furthermore, the material components for preparing the fire-resistant and corrosion-resistant concrete also include a rust inhibitor, and the rust inhibitor is used in an amount of 0.8-1.2 parts by mass.

[0015] Furthermore, the rust inhibitor is a phosphate rust inhibitor, a chromium salt rust inhibitor, an organic rust inhibitor, or a composite rust inhibitor.

[0016] A method for preparing fire-resistant and corrosion-resistant concrete comprises the following steps: Step 1: Take cement, fly ash, slag powder, fine aggregate, fine aggregate, water reducer, corrosion inhibitor, rust inhibitor and water in proportion, put them into a mixer, and mix them until a uniform concrete mortar is obtained. The specific material proportion is: by mass, Cement: 100 parts Fly ash: 20-30 parts Slag powder: 10-15 parts Fine aggregate: 150-250 parts Coarse aggregate: 300-450 parts Refractory fiber material: 10-20 parts; Water: 50-70 parts; Corrosion resistance agent: 1-2 parts; Water reducing agent: 0.7-1 part; Rust inhibitor 0.8-1.2 parts; Step 2: Cut the refractory fiber material into pieces with a length of 1.5 cm to 5 cm, gradually add the refractory fiber material into the concrete mortar, stir evenly, and ensure that the refractory fiber material is evenly distributed therein; and obtain refractory and corrosion-resistant concrete.

[0017] Step 3: Pour part of the fire-resistant and corrosion-resistant concrete into the mold, vibrate, level and fully compact it to ensure that the concrete is full and the generation of pores is minimized; Step 4: After the concrete is formed, it is put into a curing box for curing to obtain a fire-resistant and corrosion-resistant concrete specimen; Step 5: Dry the fire-resistant and anti-corrosion concrete specimens, and then conduct concrete corrosion resistance tests and fire resistance performance tests to confirm the fire resistance and corrosion resistance of the fire-resistant and anti-corrosion concrete.

[0018] The beneficial effects of the present invention are: The present invention adds fly ash and slag powder to concrete, and the fly ash and slag powder can fill the microscopic pores in the concrete, reduce the porosity of the concrete, and improve the compactness of the concrete. At the same time, the fly ash and slag powder contain a large amount of active ingredients such as silicate and iron oxide, which react with water and cement in the concrete to form a cement, fill the internal pores of the concrete, and improve the strength and corrosion resistance of the concrete. At the same time, the present invention also adds a chloride control agent to the concrete to reduce the penetration and permeation of chloride ions in the concrete, thereby reducing the risk of steel bar corrosion and concrete cracking caused by chloride ions in the concrete. Through the combined use of fly ash, slag powder and chloride control agent, the present invention can effectively improve the anti-corrosion performance of concrete.

[0019] The present invention adds refractory fiber material to concrete, and in order to fully mix the refractory fiber material with concrete, the refractory fiber material is cut into thin strips of 1.5 cm to 5 cm, and gradually added into the concrete mortar and stirred evenly. The refractory fiber material can effectively improve the residual strength of the concrete after being burned, thereby making the concrete have high fire resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the content diagram of concrete with different proportions in the embodiment; Figure 2 Graph showing chloride ion penetration electricity of concrete with different proportions in the embodiment. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0022] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0023] Unless otherwise defined, the technical terms or scientific terms involved in this application should be understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantitative limitation and may indicate the singular or plural. The terms "include", "comprise", "have" and any of their variations involved in this application are intended to cover non-exclusive inclusions; for example, a process, method, system, product or device that includes a series of steps or units (units) is not limited to the listed steps or units, but may also include unlisted steps or units, or may also include other steps or units inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" / "several" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships, for example, "A and / or B" can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0024] First embodiment: Fire-resistant and anti-corrosion concrete, the formula is: In parts by mass, the amount of each material component is: Portland cement: 100kg; Secondary fly ash: 20kg; Slag powder: 15kg; Quartz sand with particle size less than 5mm: 150kg; Ceramic aggregate with particle size greater than 5mm: 450kg; Potassium chloride: 2kg; Steel fiber: 20kg; Water: 70kg; SN-Ⅱ water reducing agent 1kg; 1.2kg organic rust inhibitor.

[0025] The method for preparing fire-resistant and corrosion-resistant concrete specifically comprises the following steps: Step 1: Add the above proportions of Portland cement, secondary fly ash, slag powder, ceramsite aggregate, quartz sand and water into a mixer and stir for 120 seconds. Then add SN-Ⅱ water reducer and organic rust inhibitor and continue stirring for 60 seconds. Step 2: Cut the steel fibers to a length between 1.5 cm and 5 cm. The length can be within this range. The length of each steel fiber does not have to be exactly the same. Add the steel fibers gradually into the concrete mortar at a rate of 2 portions every 5 seconds. After the steel fibers are added, stir for another 120 seconds to obtain fire-resistant and corrosion-resistant concrete.

[0026] Step 3: Take out the fire-resistant and anti-corrosion concrete and pour it into a test block mold of 10×10×10 cm, shake it, level it and fully compact it, let it stand for 24 hours, and then take out the concrete block from the test block mold; Step 4: Place the concrete blocks in a curing box for 28 days, during which time the concrete blocks are kept warm and moisturized.

[0027] Step 5. Take the concrete blocks out of the curing box and dry them. Then, conduct concrete corrosion resistance test and fire resistance test. The concrete corrosion resistance test adopts chloride ion diffusion test: by immersing concrete specimens or applying chloride salt solution on the surface of concrete specimens, the diffusion depth of chloride ions in concrete is measured to evaluate the concrete's resistance to chloride ion penetration.

[0028] Second embodiment: Compared with the first embodiment, only the formula is different, and the preparation method of the fire-resistant and anti-corrosion concrete is the same. Specifically: Fire-resistant and anti-corrosion concrete, the formula is: In parts by mass, the amount of each material component is: Portland cement: 100kg; Secondary fly ash: 30kg; Slag powder: 10kg; Quartz sand with particle size less than 5mm: 250kg; Ceramic aggregate with particle size greater than 5mm: 450kg; Potassium chloride: 1kg; Glass fiber: 20kg; Water: 70kg; SN-Ⅱ water reducing agent 1kg; Phosphate rust inhibitor 1.2kg.

[0029] The third embodiment: Compared with the first embodiment, only the formula is different, and the preparation method of the fire-resistant and anti-corrosion concrete is the same. Specifically: Fire-resistant and anti-corrosion concrete, the formula is: In parts by mass, the amount of each material component is: Portland cement: 100kg; Secondary fly ash: 25kg; Slag powder: 12.4kg; Quartz sand with particle size less than 5mm: 200kg; Ceramic aggregate with particle size greater than 5mm: 400kg; Sodium chloride: 1kg; Polypropylene fiber: 20kg; Water: 50kg; SN-Ⅱ water reducing agent 1kg; Chromium salt rust inhibitor 1kg.

[0030] Fourth embodiment: Compared with the first embodiment, only the formula is different, and the preparation method of the fire-resistant and anti-corrosion concrete is the same. Specifically: Fire-resistant and anti-corrosion concrete, the formula is: In parts by mass, the amount of each material component is: Portland cement: 100kg; Secondary fly ash: 30kg; Slag powder: 12kg; Quartz sand with particle size less than 5mm: 225kg; Ceramic aggregate with particle size greater than 5mm: 355kg; Sodium chloride: 1kg; Polyethylene fiber: 20kg; Water: 50kg; SN-Ⅱ water reducing agent 1kg; Composite rust inhibitor 1kg.

[0031] A group of concrete test blocks prepared by the method for preparing fire-resistant and corrosion-resistant concrete are given below, and the specific formula is shown in Table 1: Among them, the concrete specimen numbered 1 is the reference group.

[0032] The above concrete test blocks were used to carry out concrete corrosion resistance test and fire resistance test. The concrete corrosion resistance test results are as follows: Figure 1 The fire resistance test results are shown in Figure 2 shown.

[0033] from Figure 1 It can be concluded that after adding fly ash, slag powder, refractory fiber materials and corrosion resistant agents to concrete, the corrosion resistance test and fire resistance of the concrete test blocks are significantly improved. Taking No. 2 and No. 10 as examples, the only difference between No. 2 and No. 10 is the amount of refractory fiber materials added. The 7-day chloride ion penetration charge of No. 2 is 769C, and the 7-day chloride ion penetration charge of No. 10 is 770C. The 28-day chloride ion penetration charge of No. 2 is 1001C, and the 7-day chloride ion penetration charge of No. 10 is 1003C, with almost no difference. The chloride ion permeation charges of other specimens also show that the refractory fiber material has no obvious effect on the corrosion resistance of the concrete specimens. The chloride ion permeation charge of No. 6 after 7 days is 764C, and the chloride ion permeation charge after 28 days is 990C. Compared with No. 2, it shows that fly ash has a certain help on the corrosion resistance of the concrete specimens. The chloride ion permeation charge of No. 13 after 7 days is 703C, and the chloride ion permeation charge after 28 days is 880C. Compared with No. 2 and No. 13, it can be seen that adding slag powder and corrosion inhibitors has a significant positive effect on the corrosion resistance of the concrete specimens.

[0034] from Figure 2 It can be seen that the present invention can effectively improve the high-temperature bearing capacity of concrete after adding fly ash, slag powder, refractory fiber material and corrosion resistant agent, wherein the more refractory fiber material is added, the higher the high-temperature bearing capacity is.

[0035] In summary, it can be concluded that the concrete of the present invention has higher corrosion resistance and fire resistance, and the effects come from fly ash, slag powder, corrosion resistance agent and refractory fiber material.

[0036] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A fire-resistant and corrosion-resistant concrete, characterized in that: The material components for preparing fire-resistant and anti-corrosion concrete include cement, fly ash, slag powder, coarse aggregate, fine aggregate, refractory fiber material, corrosion resistant agent and water, wherein the amount of each material component is as follows, calculated by mass: Cement: 100 parts; Fly ash: 20-30 parts; Slag powder: 10-15 parts; Fine aggregate: 150-250 parts; Coarse aggregate: 300-450 parts; Refractory fiber material: 10-20 parts; Corrosion resistance agent: 1-2 parts; Water: 50-70 parts.

2. The fire-resistant and corrosion-resistant concrete according to claim 1 is characterized in that: The material components for preparing the fire-resistant and anti-corrosion concrete also include a water reducing agent, and the amount of the water reducing agent is 0.7-1 part by mass.

3. The fire-resistant and corrosion-resistant concrete according to claim 2 is characterized in that: The water reducing agent is SN-Ⅱ.

4. The fire-resistant and corrosion-resistant concrete according to claim 2 is characterized in that: The coarse aggregate is ceramsite aggregate with a particle size of 5mm-20mm.

5. The fire-resistant and corrosion-resistant concrete according to claim 2 is characterized in that: The fine aggregate is sand with a particle size of 0.15mm-5mm.

6. The fire-resistant and corrosion-resistant concrete according to claim 2 is characterized in that: The refractory fiber material is steel fiber or glass fiber or polypropylene fiber or polyethylene fiber; the corrosion resistant agent is a chloride control agent.

7. The fire-resistant and corrosion-resistant concrete according to claim 2 is characterized in that: The material components for preparing the fire-resistant and anti-corrosion concrete also include a rust inhibitor, and the rust inhibitor is used in an amount of 0.8-1.2 parts by mass.

8. The fire-resistant and corrosion-resistant concrete according to claim 2 is characterized in that: The rust inhibitor is a phosphate rust inhibitor, a chromium salt rust inhibitor, an organic rust inhibitor or a composite rust inhibitor.

9. A method for preparing fire-resistant and corrosion-resistant concrete, characterized in that: The specific steps include: Step 1: Take cement, fly ash, slag powder, fine aggregate, fine aggregate, water reducer, corrosion inhibitor, rust inhibitor and water in proportion, put them into a mixer, and mix them until a uniform concrete mortar is obtained. The specific material proportion is: by mass, Cement: 100 parts; Fly ash: 20-30 parts; Slag powder: 10-15 parts; Fine aggregate: 150-250 parts; Coarse aggregate: 300-450 parts; Refractory fiber material: 10-20 parts; Corrosion resistance agent: 1-2 parts; Water: 50-70 parts; Water reducing agent: 0.7-1 part; Rust inhibitor 0.8-1.2 parts; Step 2: Cut the refractory fiber material into pieces with a length between 1.5 cm and 5 cm, gradually add the refractory fiber material into the concrete mortar, and stir evenly to ensure that the refractory fiber material is evenly distributed therein; Fire-resistant and corrosion-resistant concrete is obtained.

10. The method for preparing fire-resistant and corrosion-resistant concrete according to claim 9, characterized in that: The step also includes the following steps: pouring part of the fire-resistant and corrosion-resistant concrete into the mold, vibrating, leveling and fully compacting the concrete to ensure that the concrete is full and the generation of pores is minimized; Step 4: After the concrete is formed, it is put into a curing box for curing to obtain a fire-resistant and corrosion-resistant concrete specimen; Step 5: Dry the fire-resistant and anti-corrosion concrete specimens, and then conduct concrete corrosion resistance tests and fire resistance performance tests to confirm the fire resistance and anti-corrosion properties of the fire-resistant and anti-corrosion concrete.

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