Anti-freezing and anti-cracking concrete and preparation method thereof

Abstract

The invention provides anti-freezing and anti-cracking concrete. The anti-freezing and anti-cracking concrete is prepared from the following components in parts by weight: 1500 to 2000 parts of coarse aggregate, 800 to 1100 parts of fine aggregate, 300 to 450 parts of water, 120 to 170 parts of admixture, 50 to 70 parts of bonding enhancer, 25 to 36 parts of air content agent, 17 to 22 parts of water reducing agent and 12 to 16 parts of fiber enhancer. The bonding enhancer is added into the raw materials of the concrete, so that the bonding performance and crack resistance of the concrete can be improved, the cohesive force of the concrete is enhanced, the cracking risk is reduced, the air content agent can form tiny bubbles in the concrete, and the bubbles can absorb freeze-thaw water and reduce the frost heaving pressure; the water reducing agent can improve the flowability and the working performance of the concrete and reduce pore structures in the concrete at the same time, fiber reinforced materials such as polypropylene fibers or steel fibers are added, the crack resistance and the toughness of the concrete can be remarkably improved, and the fibers can bear part of tensile force, so that the anti-freezing performance and the anti-cracking performance of the concrete are improved. And the cracking possibility is reduced.

Description

Technical Field

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

[0002] Concrete is a building material made of cement, aggregates (such as sand and gravel) and water in a certain proportion. It is a versatile material that is widely used in construction, infrastructure, roads, bridges, water conservancy projects and other fields. The process of making concrete involves mixing cement with aggregates and adding water during the mixing process to make the mixture form a uniform slurry. Over time, concrete will undergo chemical reactions to form a solid structure that hardens and solidifies.

[0003] However, existing concrete has the following problems during use: (1) Ordinary concrete is prone to cracks and wear when subjected to impact and friction, which reduces its durability and service life, and concrete shrinks during the drying and hardening process, which may cause cracking and deformation, especially in large-volume concrete structures such as dams and bridges; (2) Concrete is very sensitive to temperature changes and may crack and deform under extreme temperature conditions, for example: poor anti-freezing ability in low-temperature environments. Therefore, it is necessary to design corresponding technical solutions to solve the existing technical problems. Summary of the invention

[0004] The purpose of the present invention is to provide a frost-resistant and crack-resistant concrete and a preparation method thereof, which solves the technical problem that ordinary concrete is prone to cracks and wear when subjected to impact and friction, reducing its durability and service life, and that concrete shrinks during the drying and hardening process, which may cause cracking and deformation, especially in large-volume concrete structures such as dams and bridges. Concrete is very sensitive to temperature changes and may crack and deform under extreme temperature conditions, for example: poor antifreeze ability in low temperature environments.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical scheme: a frost-resistant and crack-resistant concrete, which comprises, by weight, 1500-2000 parts of coarse aggregate, 800-1100 parts of fine aggregate, 300-450 parts of water, 120-170 parts of admixture, 50-70 parts of bonding enhancer, 25-36 parts of air content agent, 17-22 parts of water reducer and 12-16 parts of fiber reinforcement.

[0006] As a preferred embodiment of the present invention, the specific weight ratio includes 1800 parts of coarse aggregate, 950 parts of fine aggregate, 370 parts of water, 150 parts of admixture, 60 parts of bonding enhancer, 30 parts of air content agent, 20 parts of water reducer and 14 parts of fiber reinforcement.

[0007] As a preferred embodiment of the present invention, the admixture is selected from two or more of fly ash, silica ash and slag powder, and the raw materials are dried and refined to ensure that the raw material particle diameter is 1mm-3mm.

[0008] As a preferred embodiment of the present invention, the adhesion enhancer is selected from three or more of silicone, polymer emulsion, acrylate copolymer, polymer nanocomposite material and polypropylene fiber, and the selected adhesion enhancers need to be premixed for use.

[0009] As a preferred embodiment of the present invention, the fiber reinforcement is selected from one or more of polypropylene fiber and steel fiber.

[0010] As a preferred embodiment of the present invention, the specific preparation steps are as follows:

[0011] S1: Premixing of concrete raw materials, introducing coarse aggregate, fine aggregate, water and admixtures in the raw materials into a concrete mixer according to the above proportions, and performing rotary mixing of the raw materials by the concrete mixer to mix the raw materials into a slurry;

[0012] S2: Deep processing of the concrete raw material mixture, adding asphalt to the stirred concrete, controlling the ratio of asphalt to the concrete raw material mixture at 1:10, and then continuously stirring to fully blend the asphalt and the concrete raw material mixture to obtain a pre-finished product;

[0013] S3: The operation of adding and introducing the concrete pre-finished product, the bonding enhancer, air content agent, water reducing agent and fiber reinforcing agent in the raw materials are introduced into the concrete mixer containing the pre-finished product in sequence for continuous mixing, and the mixing time is controlled within 30min-40min;

[0014] S4: The finished concrete product is poured and used. The mixed concrete slurry is poured into the predetermined construction site for pouring. During the pouring process, when pouring in a low temperature environment, the concrete slurry can be pre-cooled by refrigeration equipment. The difference between the pre-cooling temperature and the outside temperature is controlled to be less than 10°C, and the uniformity and density of the concrete are ensured;

[0015] S5: Concrete vibration exhaust treatment. After the concrete is poured, a vibrator is used to vibrate the concrete. The purpose of vibration is to remove bubbles in the concrete, improve the density and strength, and ensure the quality of the concrete.

[0016] S6: Concrete curing operation. After the concrete is vibrated, it is cured to maintain the humidity and temperature of the concrete, promote the hydration reaction of the cement, and gradually gain strength and durability of the concrete. The concrete is periodically covered and moisturized, sprayed with water, and treated with curing agents.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention adds bonding enhancer, air content agent, water reducing agent and fiber reinforcement agent to the raw materials of concrete. The bonding enhancer can improve the bonding performance and crack resistance of concrete. These additives can form more gelling substances in concrete, enhance the cohesion of concrete and reduce the risk of cracking. The air content agent is a chemical additive that can form tiny bubbles in concrete. These bubbles can absorb freeze-thaw water and reduce frost heave pressure, thereby improving the anti-freeze and anti-cracking ability of concrete. The water reducing agent can improve the fluidity and workability of concrete and reduce the pore structure in concrete, which is helpful to improve the anti-freeze and anti-cracking ability of concrete. Adding fiber reinforcement materials, such as polypropylene fiber or steel fiber, can significantly improve the crack resistance and toughness of concrete. These fibers can bear part of the tensile force and reduce the possibility of cracking, thereby improving the anti-freeze and anti-cracking effect of the finished concrete.

[0019] 2. In the process of processing and laying of concrete, the present invention can improve the adhesion of the concrete pre-finished product and ensure the strength of the concrete by premixing the main raw materials of the concrete and adding asphalt. In addition, the additives added subsequently can further improve the frost resistance and crack resistance of the concrete finished product. In the process of laying, precooling is adopted for areas with low ambient temperature to avoid the possibility of cracks in the concrete slurry during the laying process due to too low temperature, and a vibrator is used to vibrate the concrete. The purpose of vibration is to eliminate bubbles in the concrete, improve the density and strength, ensure the quality of the concrete, and greatly improve the frost resistance and crack resistance of the concrete after the laying process. DETAILED DESCRIPTION

[0020] Embodiment 1:

[0021] A frost-resistant and crack-resistant concrete comprises, by weight, 1,500 parts of coarse aggregate, 800 parts of fine aggregate, 300 parts of water, 120 parts of admixture, 50 parts of bonding enhancer, 25 parts of air content agent, 17 parts of water reducer and 12 parts of fiber reinforcement.

[0022] The specific preparation steps are as follows:

[0023] S1: Premixing of concrete raw materials, introducing coarse aggregate, fine aggregate, water and admixtures in the raw materials into a concrete mixer according to the above proportions, and performing rotary mixing of the raw materials by the concrete mixer to mix the raw materials into a slurry;

[0024] S2: Deep processing of the concrete raw material mixture, adding asphalt to the stirred concrete, controlling the ratio of asphalt to the concrete raw material mixture at 1:10, and then continuously stirring to fully blend the asphalt and the concrete raw material mixture to obtain a pre-finished product;

[0025] S3: The operation of adding and introducing the concrete pre-finished product, the bonding enhancer, air content agent, water reducing agent and fiber reinforcing agent in the raw materials are introduced into the concrete mixer containing the pre-finished product in sequence for continuous mixing, and the mixing time is controlled within 30min-40min;

[0026] S4: The finished concrete product is poured and used. The mixed concrete slurry is poured into the predetermined construction site for pouring. During the pouring process, when pouring in a low temperature environment, the concrete slurry can be pre-cooled by refrigeration equipment. The difference between the pre-cooling temperature and the outside temperature is controlled to be less than 10°C, and the uniformity and density of the concrete are ensured;

[0027] S5: Concrete vibration exhaust treatment. After the concrete is poured, a vibrator is used to vibrate the concrete. The purpose of vibration is to remove bubbles in the concrete, improve the density and strength, and ensure the quality of the concrete.

[0028] S6: Concrete curing operation. After the concrete is vibrated, it is cured to maintain the humidity and temperature of the concrete, promote the hydration reaction of the cement, and gradually gain strength and durability of the concrete. The concrete is periodically covered and moisturized, sprayed with water, and treated with curing agents.

[0029] The present invention adds an adhesive enhancer, an air content agent, a water reducer and a fiber reinforcement agent to the raw materials of concrete. The adhesive enhancer can improve the adhesive performance and crack resistance of concrete. These additives can form more gelling substances in concrete, enhance the cohesion of concrete and reduce the risk of cracking. The air content agent is a chemical additive that can form tiny bubbles in concrete. These bubbles can absorb freeze-thaw water and reduce frost heave pressure, thereby improving the anti-freeze and anti-cracking ability of concrete. The water reducer can improve the fluidity and workability of concrete and reduce the pore structure in concrete, which is helpful to improve the anti-freeze and anti-cracking ability of concrete. Adding fiber reinforcement materials, such as polypropylene fiber or steel fiber, can significantly improve the crack resistance and toughness of concrete. These fibers can To bear part of the tensile force and reduce the possibility of cracking, thereby improving the anti-freeze and anti-cracking effect of the finished concrete product. During the processing and paving of concrete, by premixing the main raw materials of concrete and adding asphalt, the adhesion of the concrete pre-finished product can be improved and the strength of the concrete can be ensured. In addition, the additives added later can further improve the anti-freeze and anti-cracking ability of the finished concrete product. During the paving process, pre-cooling is adopted in areas with low ambient temperature to avoid the possibility of cracks in the concrete slurry during the paving process due to low temperature, and a vibrator is used to vibrate the concrete. The purpose of vibration is to eliminate bubbles in the concrete, improve the density and strength, ensure the quality of concrete, and greatly improve the anti-freeze and anti-cracking ability of the concrete after the paving process.

[0030] Embodiment 2:

[0031] A frost-resistant and crack-resistant concrete comprises, by weight, 1,800 parts of coarse aggregate, 950 parts of fine aggregate, 370 parts of water, 150 parts of admixture, 60 parts of bonding enhancer, 30 parts of air content agent, 20 parts of water reducer and 14 parts of fiber reinforcement.

[0032] The specific preparation steps are as follows:

[0033] S1: Premixing of concrete raw materials, introducing coarse aggregate, fine aggregate, water and admixtures in the raw materials into a concrete mixer according to the above proportions, and performing rotary mixing of the raw materials by the concrete mixer to mix the raw materials into a slurry;

[0034] S2: Deep processing of the concrete raw material mixture, adding asphalt to the stirred concrete, controlling the ratio of asphalt to the concrete raw material mixture at 1:10, and then continuously stirring to fully blend the asphalt and the concrete raw material mixture to obtain a pre-finished product;

[0035] S3: The operation of adding and introducing the concrete pre-finished product, the bonding enhancer, air content agent, water reducing agent and fiber reinforcing agent in the raw materials are introduced into the concrete mixer containing the pre-finished product in sequence for continuous mixing, and the mixing time is controlled within 30min-40min;

[0036] S4: The finished concrete product is poured and used. The mixed concrete slurry is poured into the predetermined construction site for pouring. During the pouring process, when pouring in a low temperature environment, the concrete slurry can be pre-cooled by refrigeration equipment. The difference between the pre-cooling temperature and the outside temperature is controlled to be less than 10°C, and the uniformity and density of the concrete are ensured;

[0037] S5: Concrete vibration exhaust treatment. After the concrete is poured, a vibrator is used to vibrate the concrete. The purpose of vibration is to remove bubbles in the concrete, improve the density and strength, and ensure the quality of the concrete.

[0038] S6: Concrete curing operation. After the concrete is vibrated, it is cured to maintain the humidity and temperature of the concrete, promote the hydration reaction of the cement, and gradually gain strength and durability of the concrete. The concrete is periodically covered and moisturized, sprayed with water, and treated with curing agents.

[0039] The present invention adds an adhesive enhancer, an air content agent, a water reducer and a fiber reinforcement agent to the raw materials of concrete. The adhesive enhancer can improve the adhesive performance and crack resistance of concrete. These additives can form more gelling substances in concrete, enhance the cohesion of concrete and reduce the risk of cracking. The air content agent is a chemical additive that can form tiny bubbles in concrete. These bubbles can absorb freeze-thaw water and reduce frost heave pressure, thereby improving the anti-freeze and anti-cracking ability of concrete. The water reducer can improve the fluidity and workability of concrete and reduce the pore structure in concrete, which is helpful to improve the anti-freeze and anti-cracking ability of concrete. Adding fiber reinforcement materials, such as polypropylene fiber or steel fiber, can significantly improve the crack resistance and toughness of concrete. These fibers can To bear part of the tensile force and reduce the possibility of cracking, thereby improving the anti-freeze and anti-cracking effect of the finished concrete product. During the processing and paving of concrete, by premixing the main raw materials of concrete and adding asphalt, the adhesion of the concrete pre-finished product can be improved and the strength of the concrete can be ensured. In addition, the additives added later can further improve the anti-freeze and anti-cracking ability of the finished concrete product. During the paving process, pre-cooling is adopted in areas with low ambient temperature to avoid the possibility of cracks in the concrete slurry during the paving process due to low temperature, and a vibrator is used to vibrate the concrete. The purpose of vibration is to eliminate bubbles in the concrete, improve the density and strength, ensure the quality of concrete, and greatly improve the anti-freeze and anti-cracking ability of the concrete after the paving process.

[0040] Embodiment 3:

[0041] A frost-resistant and crack-resistant concrete comprises 2000 parts of mortar, 1100 parts of fine aggregate, 450 parts of water, 170 parts of admixture, 70 parts of bonding enhancer, 36 parts of air content agent, 22 parts of water reducer and 16 parts of fiber reinforcement in specific weight proportions.

[0042] The specific preparation steps are as follows:

[0043] S1: Premixing of concrete raw materials, introducing coarse aggregate, fine aggregate, water and admixtures in the raw materials into a concrete mixer according to the above proportions, and performing rotary mixing of the raw materials by the concrete mixer to mix the raw materials into a slurry;

[0044] S2: Deep processing of the concrete raw material mixture, adding asphalt to the stirred concrete, controlling the ratio of asphalt to the concrete raw material mixture at 1:10, and then continuously stirring to fully blend the asphalt and the concrete raw material mixture to obtain a pre-finished product;

[0045] S3: The operation of adding and introducing the concrete pre-finished product, the bonding enhancer, air content agent, water reducing agent and fiber reinforcing agent in the raw materials are introduced into the concrete mixer containing the pre-finished product in sequence for continuous mixing, and the mixing time is controlled within 30min-40min;

[0046] S4: The finished concrete product is poured and used. The mixed concrete slurry is poured into the predetermined construction site for pouring. During the pouring process, when pouring in a low temperature environment, the concrete slurry can be pre-cooled by refrigeration equipment. The difference between the pre-cooling temperature and the outside temperature is controlled to be less than 10°C, and the uniformity and density of the concrete are ensured;

[0047] S5: Concrete vibration exhaust treatment. After the concrete is poured, a vibrator is used to vibrate the concrete. The purpose of vibration is to remove bubbles in the concrete, improve the density and strength, and ensure the quality of the concrete.

[0048] S6: Concrete curing operation. After the concrete is vibrated, it is cured to maintain the humidity and temperature of the concrete, promote the hydration reaction of the cement, and gradually gain strength and durability of the concrete. The concrete is periodically covered and moisturized, sprayed with water, and treated with curing agents.

[0049] The present invention adds an adhesive enhancer, an air content agent, a water reducer and a fiber reinforcement agent to the raw materials of concrete. The adhesive enhancer can improve the adhesive performance and crack resistance of concrete. These additives can form more gelling substances in concrete, enhance the cohesion of concrete and reduce the risk of cracking. The air content agent is a chemical additive that can form tiny bubbles in concrete. These bubbles can absorb freeze-thaw water and reduce frost heave pressure, thereby improving the anti-freeze and anti-cracking ability of concrete. The water reducer can improve the fluidity and workability of concrete and reduce the pore structure in concrete, which is helpful to improve the anti-freeze and anti-cracking ability of concrete. Adding fiber reinforcement materials, such as polypropylene fiber or steel fiber, can significantly improve the crack resistance and toughness of concrete. These fibers can To bear part of the tensile force and reduce the possibility of cracking, thereby improving the anti-freeze and anti-cracking effect of the finished concrete product. During the processing and paving of concrete, by premixing the main raw materials of concrete and adding asphalt, the adhesion of the concrete pre-finished product can be improved and the strength of the concrete can be ensured. In addition, the additives added later can further improve the anti-freeze and anti-cracking ability of the finished concrete product. During the paving process, pre-cooling is adopted in areas with low ambient temperature to avoid the possibility of cracks in the concrete slurry during the paving process due to low temperature, and a vibrator is used to vibrate the concrete. The purpose of vibration is to eliminate bubbles in the concrete, improve the density and strength, ensure the quality of concrete, and greatly improve the anti-freeze and anti-cracking ability of the concrete after the paving process.

[0050] Embodiment 4:

[0051] A frost-resistant and crack-resistant concrete comprises 1800 parts of coarse aggregate, 950 parts of fine aggregate, 370 parts of water and 150 parts of admixture in specific weight proportions.

[0052] The specific preparation steps are as follows:

[0053] S1: Premixing of concrete raw materials, introducing coarse aggregate, fine aggregate, water and admixtures in the raw materials into a concrete mixer according to the above proportions, and performing rotary mixing of the raw materials by the concrete mixer to mix the raw materials into a slurry to obtain a pre-finished product;

[0054] S2: The finished concrete is poured and used. The mixed concrete slurry is poured into the predetermined construction site for pouring. During the pouring process, when pouring in a low temperature environment, the concrete slurry can be pre-cooled by refrigeration equipment. The difference between the pre-cooling temperature and the outside temperature is controlled to be less than 10°C, and the uniformity and density of the concrete are ensured.

[0055] S3: Concrete curing operation, which maintains the humidity and temperature of the concrete, promotes the hydration reaction of cement, and gradually enables the concrete to gain strength and durability. The concrete is periodically covered to keep it moist, sprayed with water, and treated with curing agents.

[0056] According to the above four groups of embodiments, concrete was processed and laid, and the concrete laying effects produced by the concrete processing and laying methods adopted in each embodiment were observed, as follows:

[0057]

[0058] According to the analysis of the above table, the designed concrete raw materials and processing methods are known. By adding bonding enhancers, air content agents, water reducers and fiber reinforcements to the raw materials, the bonding enhancers can improve the bonding properties and crack resistance of concrete. These additives can form more gelling substances in the concrete, enhance the cohesion of the concrete, and reduce the risk of cracking. The air content agent is a chemical additive that can form tiny bubbles in the concrete. These bubbles can absorb freeze-thaw water and reduce frost heave pressure, thereby improving the concrete's resistance to freezing and cracking. The water reducer can improve the fluidity and workability of the concrete, while reducing the pore structure in the concrete, which helps to improve the concrete's resistance to freezing and cracking. Adding fiber reinforcement materials, such as polypropylene fibers or steel fibers, can significantly improve the concrete's crack resistance. Energy and toughness, these fibers can bear part of the tension and reduce the possibility of cracking, thereby improving the frost and crack resistance of the finished concrete. During the processing and laying of concrete, by premixing the main raw materials of concrete and adding asphalt, the adhesion of the concrete pre-finished product can be improved and the strength of the concrete can be guaranteed. In addition, the additives added later can further improve the frost and crack resistance of the finished concrete. During the laying process, pre-cooling is used in areas with low ambient temperature to avoid the possibility of cracks in the concrete slurry during the laying process due to low temperature, and a vibrator is used to vibrate the concrete. The purpose of vibration is to eliminate bubbles in the concrete, improve the density and strength, ensure the quality of concrete, and greatly improve the frost and crack resistance of the concrete after the laying process.

[0059] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A frost-resistant and crack-resistant concrete, characterized in that: The weight ratio includes 1500-2000 parts of coarse aggregate, 800-1100 parts of fine aggregate, 300-450 parts of water, 120-170 parts of admixture, 50-70 parts of bonding enhancer, 25-36 parts of air content agent, 17-22 parts of water reducer and 12-16 parts of fiber reinforcement.

2. The frost-resistant and crack-resistant concrete according to claim 1, characterized in that: The specific weight ratio includes 1,800 parts of coarse aggregate, 950 parts of fine aggregate, 370 parts of water, 150 parts of admixture, 60 parts of bonding enhancer, 30 parts of air content agent, 20 parts of water reducer and 14 parts of fiber reinforcement.

3. The frost-resistant and crack-resistant concrete according to claim 1, characterized in that: The admixture is selected from two or more of fly ash, silica ash and slag powder, and the raw materials are dried and refined to ensure that the raw material particle diameter is 1mm-3mm.

4. The frost-resistant and crack-resistant concrete according to claim 1, characterized in that: The bonding enhancer is selected from three or more of silicone, polymer emulsion, acrylate copolymer, polymer nanocomposite material and polypropylene fiber, and the selected bonding enhancers need to be premixed for use.

5. The frost-resistant and crack-resistant concrete according to claim 1, characterized in that: The fiber reinforcement is selected from one or more of polypropylene fiber and steel fiber.

6. The method for preparing frost-resistant and crack-resistant concrete according to claim 1, characterized in that: The specific preparation steps are as follows: S1: Premixing of concrete raw materials, introducing coarse aggregate, fine aggregate, water and admixtures in the raw materials into a concrete mixer according to the above proportions, and performing rotary mixing of the raw materials by the concrete mixer to mix the raw materials into a slurry; S2: Deep processing of the concrete raw material mixture, adding asphalt to the stirred concrete, controlling the ratio of asphalt to the concrete raw material mixture at 1:10, and then continuously stirring to fully blend the asphalt and the concrete raw material mixture to obtain a pre-finished product; S3: The operation of adding and introducing the concrete pre-finished product, the bonding enhancer, air content agent, water reducing agent and fiber reinforcing agent in the raw materials are introduced into the concrete mixer containing the pre-finished product in sequence for continuous mixing, and the mixing time is controlled within 30min-40min; S4: The finished concrete product is poured and used. The mixed concrete slurry is poured into the predetermined construction site for pouring. During the pouring process, when pouring in a low temperature environment, the concrete slurry can be pre-cooled by refrigeration equipment. The difference between the pre-cooling temperature and the outside temperature is controlled to be less than 10°C, and the uniformity and density of the concrete are ensured; S5: Concrete vibration exhaust treatment. After the concrete is poured, a vibrator is used to vibrate the concrete. The purpose of vibration is to remove bubbles in the concrete, improve the density and strength, and ensure the quality of the concrete. S6: Concrete curing operation. After the concrete is vibrated, it is cured to maintain the humidity and temperature of the concrete, promote the hydration reaction of the cement, and gradually gain strength and durability of the concrete. The concrete is periodically covered and moisturized, sprayed with water, and treated with curing agents.

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