Concrete suitable for high-temperature construction environment and preparation method thereof

Abstract

The invention relates to the technical field of concrete, and particularly discloses concrete suitable for a high-temperature construction environment and a preparation method of the concrete. The invention discloses concrete suitable for a high-temperature construction environment. The concrete is prepared from 150 to 200 parts of cement, 60 to 75 parts of fly ash, 60 to 80 parts of mineral powder, 720 to 800 parts of machine-made sand, 980 to 1150 parts of gravel, 10 to 20 parts of manganese slag powder, 3 to 5 parts of ethylene-vinyl acetate copolymer, 8 to 12 parts of additive, 110 to 140 parts of water and 100 to 130 parts of ice blocks, the additive is prepared by dissolving hydroxy propyl cellulose, fatty alcohol-polyoxyethylene ether and sodium allysulfonate in water. The concrete disclosed by the invention not only can keep good working performance and strength development under a high-temperature condition, but also has excellent crack resistance.

Description

Technical Field

[0001] The invention relates to the technical field of concrete, and in particular to concrete suitable for high-temperature construction environments and a preparation method thereof. Background Art

[0002] The construction environment of concrete is complex and diverse, especially under high temperature conditions in summer, the performance of concrete will be significantly affected by the climate. Under high temperature conditions, the moisture on the surface of the poured concrete can easily evaporate, causing the surface of the concrete to shrink faster than the deep layer, resulting in a difference in shrinkage between the inside and outside, which in turn causes cracks. At the same time, high temperature may cause changes in the internal structure of concrete, increase the hydration reaction rate of concrete, shorten the hardening time, and affect the shrinkage characteristics of concrete. Therefore, it is necessary to further improve the formula of concrete to adapt to the high temperature construction environment and reduce the plastic shrinkage cracks of concrete under high temperature conditions. Summary of the invention

[0003] In order to solve the problem that concrete is prone to plastic shrinkage cracks in high-temperature construction environments, the present invention provides a concrete suitable for high-temperature construction environments and a preparation method thereof. The concrete of the present application can not only maintain good working performance and strength development under high temperature conditions, but also has excellent crack resistance.

[0004] In the first aspect, the present application provides a concrete suitable for a high temperature construction environment, which adopts the following technical scheme: a concrete suitable for a high temperature construction environment, comprising the following raw materials in parts by weight: 150 to 200 parts of cement, 60 to 75 parts of fly ash, 60 to 80 parts of mineral powder, 720 to 800 parts of machine-made sand, 980 to 1150 parts of gravel, 10 to 20 parts of manganese slag powder, 3 to 5 parts of ethylene-vinyl acetate copolymer, 8 to 12 parts of admixture, 110 to 140 parts of water, and 100 to 130 parts of ice cubes; the admixture is prepared by dissolving hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate in water.

[0005] In the above technical scheme, the present application can effectively reduce the initial temperature of the concrete by adding a specific proportion of ice cubes to the concrete, thereby slowing down the evaporation rate of water on the surface of the concrete under high temperature environment. The present application can further improve the crack resistance and durability of the concrete by introducing manganese slag powder and ethylene-vinyl acetate copolymer. By introducing an admixture prepared from hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate, the workability and strength development of the concrete can be improved. This is because hydroxypropyl cellulose has good water retention, fatty alcohol polyoxyethylene ether can improve the fluidity of concrete, and sodium allyl sulfonate can enhance the cohesiveness of concrete. The synergistic effect of these three components enables the concrete to maintain good working performance in a high temperature environment and further improves the crack resistance of the concrete.

[0006] Preferably, the weight ratio of hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate is 1:(0.7-1):(0.5-0.8).

[0007] Preferably, the weight ratio of the hydroxypropyl cellulose, the fatty alcohol polyoxyethylene ether and the sodium allyl sulfonate is 1:0.9:0.7.

[0008] In the above technical scheme, the present application can ensure that the performance of concrete in a high-temperature construction environment is more stable by limiting the weight ratio of hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether, and sodium allyl sulfonate, so that the concrete has better workability and strength development under high temperature conditions, while effectively reducing the occurrence of cracks.

[0009] Preferably, the preparation method of the admixture comprises: mixing hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether, and sodium allyl sulfonate to obtain a premix, then adding an appropriate amount of water to dissolve, and stirring evenly to obtain the admixture; the mass ratio of the premixture to water is 1:(5-6).

[0010] In the above technical scheme, the present application can obtain an admixture with stable performance by precisely controlling the ratio of premix to water, thereby ensuring the uniform distribution and effective effect of the admixture in concrete, thereby better exerting its functions of water retention, flow increase, delayed setting and enhanced cohesion.

[0011] Preferably, the concrete suitable for high temperature construction environment includes the following components in parts by weight: 185 parts of cement, 70 parts of fly ash, 70 parts of mineral powder, 780 parts of machine-made sand, 1080 parts of crushed stone, 15 parts of manganese slag powder, 4.3 parts of ethylene-vinyl acetate copolymer, 10.7 parts of admixture, 130 parts of water, and 120 parts of ice.

[0012] In the above technical solution, the present application can obtain a concrete formula with excellent performance in a high-temperature construction environment by further limiting the amount of each raw material in the concrete.

[0013] Preferably, the concrete suitable for high temperature construction environment further comprises 1 to 3 parts of sodium molybdate.

[0014] In the above technical solution, the present application can further improve the high temperature resistance of concrete by adding sodium molybdate to concrete. As an inorganic salt, sodium molybdate can work together with admixtures to further improve the water retention of concrete, inhibit excessive evaporation of water inside the concrete, improve the microstructure inside the concrete, enhance its adaptability to temperature changes, and reduce the probability of cracks while improving the working performance of the concrete.

[0015] In a second aspect, the present application provides a method for preparing concrete suitable for high temperature construction environments, which adopts the following technical solution: A method for preparing concrete suitable for high temperature construction environment comprises the following steps: Step 1: Mix cement, fly ash, mineral powder and manganese slag powder evenly to obtain a dry mix; mix ethylene-vinyl acetate copolymer, admixture, water and ice cubes evenly to obtain a solid-liquid mixture; Step 2: Mix the machine-made sand, crushed stone and solid-liquid mixture evenly, then add the dry mix and stir evenly to obtain concrete suitable for high temperature construction environment.

[0016] Preferably, the method comprises the following steps: Step 1: Mix cement, fly ash, mineral powder and manganese slag powder evenly to obtain a dry mix; mix ethylene-vinyl acetate copolymer, admixture, sodium molybdate, water and ice cubes evenly to obtain a solid-liquid mixture; Step 2: Mix the machine-made sand, crushed stone and solid-liquid mixture evenly, then add the dry mix and stir evenly to obtain concrete suitable for high temperature construction environment.

[0017] In the above technical scheme, the present application can ensure that the performance of concrete in a high-temperature construction environment is more stable through the above-mentioned preparation method, so that the concrete has better workability and strength development under high temperature conditions, while effectively reducing the occurrence of cracks.

[0018] In summary, the present application includes at least one of the following beneficial technical effects: 1. The present application achieves the effect of regulating the temperature of concrete and slowing down the evaporation of concrete water by adding ice cubes into concrete. The introduction of manganese slag powder and ethylene-vinyl acetate copolymer enhances the crack resistance and durability of concrete. The use of admixtures and the synergistic effect of hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate not only improve the workability of concrete, but also promote the development of concrete strength, thereby ensuring the stable performance of concrete in high temperature environment.

[0019] 2. The present application adds sodium molybdate, and the interaction between sodium molybdate and the admixture of the present application helps to improve the internal microstructure of the concrete and enhance its adaptability to temperature changes, thereby reducing the internal stress caused by temperature fluctuations, reducing the occurrence of cracks, and further optimizing the stability and crack resistance of the concrete under high temperature construction conditions. DETAILED DESCRIPTION

[0020] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0021] Preparation Example 1 An additive is prepared by using raw materials including 1kg of hydroxypropyl cellulose, 1kg of fatty alcohol polyoxyethylene ether, 0.8kg of sodium allyl sulfonate and 14kg of water.

[0022] Among them, hydroxypropyl cellulose was purchased from Anhui Longyang Environmental Protection Technology Co., Ltd.

[0023] Among them, fatty alcohol polyoxyethylene ether was purchased from Xingtai Xinlanxing Technology Co., Ltd., product name: Penetrant JFC.

[0024] Among them, sodium allyl sulfonate was purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd.

[0025] The preparation method of the admixture is as follows: hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate are mixed to obtain a premix, and then water is added to dissolve the premix, and the admixture is obtained after stirring evenly.

[0026] Preparation Example 2 An admixture, which is different from Preparation Example 1 in that the raw materials include 1 kg hydroxypropyl cellulose, 0.7 kg fatty alcohol polyoxyethylene ether, 0.5 kg sodium allyl sulfonate and 13.2 kg water.

[0027] The preparation method of the admixture is as follows: hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate are mixed to obtain a premix, and then water is added to dissolve the premix, and the admixture is obtained after stirring evenly.

[0028] Preparation Example 3 An admixture, which is different from Preparation Example 1 in that the raw materials include 1 kg hydroxypropyl cellulose, 0.9 kg fatty alcohol polyoxyethylene ether, 0.7 kg sodium allyl sulfonate and 14.3 kg water.

[0029] The preparation method of the admixture is as follows: hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate are mixed to obtain a premix, and then water is added to dissolve the premix, and the admixture is obtained after stirring evenly.

[0030] Comparative Preparation Example 1 An additive, which is different from Preparation Example 1 in that hydroxypropyl cellulose is replaced by polyacrylamide in equal amounts.

[0031] Comparative Preparation Example 2 An additive, which is different from Preparation Example 1 in that an equal amount of fatty alcohol polyoxyethylene ether is replaced by fatty alcohol sodium sulfate.

[0032] Comparative Preparation Example 3 An admixture, which is different from Preparation Example 1 in that an equal amount of sodium allyl sulfonate is replaced by sodium lauryl sulfonate.

[0033] Example 1 A concrete suitable for a high-temperature construction environment comprises 150 kg of cement, 60 kg of fly ash, 60 kg of mineral powder, 720 kg of machine-made sand, 980 kg of crushed stone, 10 kg of manganese slag powder, 3 kg of ethylene-vinyl acetate copolymer, 8 kg of admixture, 1 kg of sodium molybdate, 110 kg of water and 100 kg of ice.

[0034] Among them, the cement is ordinary silicate PO42.5 cement produced by Southern Cement.

[0035] Among them, the fly ash is secondary fly ash.

[0036] Among them, the mineral powder is S95 grade.

[0037] Among them, the fineness modulus of artificial sand is 2.8.

[0038] Among them, the crushed stone is a continuous grade crushed stone with a particle size of 5 to 25 mm.

[0039] Among them, manganese slag powder was purchased from Anyang Xinhai Metallurgical Refractory Co., Ltd., with a particle size of less than 0.075mm.

[0040] Among them, ethylene-vinyl acetate copolymer was purchased from Jinan Xiangfeng Weiye Chemical Co., Ltd., CAS No.: 24937-78-8.

[0041] Wherein, the admixture is prepared by Preparation Example 1.

[0042] Among them, sodium molybdate was purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0043] The method for preparing concrete suitable for high temperature construction environment comprises the following steps: Step 1: Evenly mix cement, fly ash, mineral powder and manganese slag powder to obtain a dry mixture; evenly mix ethylene-vinyl acetate copolymer, admixture, sodium molybdate, water and ice cubes to obtain a solid-liquid mixture.

[0044] Step 2: Mix the machine-made sand, crushed stone and solid-liquid mixture evenly, then add the dry mix and stir evenly to obtain concrete suitable for high temperature construction environment.

[0045] Example 2 A concrete suitable for a high-temperature construction environment, which differs from Example 1 in that it includes 200 kg of cement, 75 kg of fly ash, 80 kg of mineral powder, 800 kg of machine-made sand, 1150 kg of crushed stone, 20 kg of manganese slag powder, 5 kg of ethylene-vinyl acetate copolymer, 12 kg of admixture, 140 kg of water, and 130 kg of ice.

[0046] Wherein, the admixture is prepared by Preparation Example 2.

[0047] Example 3 A concrete suitable for a high-temperature construction environment, which differs from Example 1 in that it includes 185kg of cement, 70kg of fly ash, 70kg of mineral powder, 780kg of machine-made sand, 1080kg of crushed stone, 15kg of manganese slag powder, 4.3kg of ethylene-vinyl acetate copolymer, 10.7kg of admixture, 1kg of sodium molybdate, 130kg of water, and 120kg of ice.

[0048] Among them, the admixture is prepared by Preparation Example 3.

[0049] Example 4 A concrete suitable for high temperature construction environment, which differs from Example 3 in that it does not contain sodium molybdate.

[0050] The method for preparing concrete suitable for high temperature construction environment comprises the following steps: Step 1: Mix cement, fly ash, mineral powder and manganese slag powder evenly to obtain a dry mixture; mix ethylene-vinyl acetate copolymer, admixture, water and ice cubes evenly to obtain a solid-liquid mixture.

[0051] Step 2: Mix the machine-made sand, crushed stone and solid-liquid mixture evenly, then add the dry mix and stir evenly to obtain concrete suitable for high temperature construction environment.

[0052] Comparative Example 1 A concrete suitable for high-temperature construction environment, which is different from Example 1 in that the admixture is prepared by Comparative Preparation Example 1.

[0053] Comparative Example 2 A concrete suitable for high-temperature construction environment, which is different from Example 1 in that the admixture is prepared by Comparative Preparation Example 2.

[0054] Comparative Example 3 A concrete suitable for high-temperature construction environment, which is different from Example 1 in that the admixture is prepared by Comparative Preparation Example 3.

[0055] Comparative Example 4 A concrete suitable for high-temperature construction environments, which differs from Example 1 in that an equal amount of manganese slag powder is replaced with slag.

[0056] Comparative Example 5 A concrete suitable for high-temperature construction environments, which differs from Example 1 in that an equal amount of ethylene-vinyl acetate copolymer is replaced with redispersible latex powder.

[0057] Performance verification testing environment: 35℃. Other conditions are based on GB / T 50080-2016 "Standard for Test Methods for Performance of Ordinary Concrete Mixtures" to test the initial slump, 1h slump, initial setting time and final setting time of concrete. The compressive strength of concrete at the 28th day is tested in accordance with GB / T50081-2019 "Standard for Test Methods for Mechanical Properties of Ordinary Concrete". The average number of surface cracks within 1.5 hours after concrete pouring is counted.

[0058] The above test results are shown in Table 1.

[0059] Table 1: Specifically combined with Table 1, it can be analyzed that the concrete suitable for high temperature construction environment of the present application shows excellent performance in terms of initial slump, 1h slump, initial setting time, final setting time, 28d compressive strength and number of surface cracks.

[0060] Specifically combined with the analysis of Example 1 and Comparative Examples 1-3, Comparative Examples 1-3 used different admixtures, and Example 1 showed good performance in terms of initial slump, 1h slump, initial setting time, final setting time, 28d compressive strength and number of surface cracks. It can be seen that the present application can significantly improve the workability of concrete, promote the development of concrete strength, and ensure the stable performance of concrete in high temperature environment through the synergistic effect of hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate.

[0061] Specifically combined with the analysis of Example 1 and Comparative Examples 4-5, Comparative Examples 4-5 replaced manganese slag powder and ethylene-vinyl acetate copolymer respectively. Example 1 showed good performance in initial slump, 1h slump, initial setting time, final setting time, 28d compressive strength and number of surface cracks. It can be seen that the present application enhances the crack resistance of concrete by introducing manganese slag powder and ethylene-vinyl acetate copolymer into concrete.

[0062] Specifically combining Example 3 and Example 4, it is analyzed that compared with Example 4, sodium molybdate is added in the preparation process of Example 3, and Example 3 shows good performance in initial slump, 1h slump, initial setting time, final setting time, 28d compressive strength and the number of surface cracks. It can be seen that further adding sodium molybdate to concrete, sodium molybdate and the admixture of the present application work together to further optimize the stability and crack resistance of concrete under high temperature construction conditions.

[0063] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A concrete suitable for high temperature construction environment, characterized in that: The invention comprises the following raw materials in parts by weight: 150-200 parts of cement, 60-75 parts of fly ash, 60-80 parts of mineral powder, 720-800 parts of machine-made sand, 980-1150 parts of crushed stone, 10-20 parts of manganese slag powder, 3-5 parts of ethylene-vinyl acetate copolymer, 8-12 parts of admixture, 110-140 parts of water and 100-130 parts of ice cubes; the admixture is prepared by dissolving hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate in water.

2. The concrete suitable for high temperature construction environment according to claim 1, characterized in that: The weight ratio of the hydroxypropyl cellulose, the fatty alcohol polyoxyethylene ether and the sodium allyl sulfonate is 1:(0.7-1):(0.5-0.8).

3. The concrete suitable for high temperature construction environment according to claim 1, characterized in that: The weight ratio of the hydroxypropyl cellulose, the fatty alcohol polyoxyethylene ether and the sodium allyl sulfonate is 1:0.9:0.

7.

4. The concrete suitable for high temperature construction environment according to claim 1, characterized in that: The preparation method of the additive comprises: mixing hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate to obtain a premix, then adding an appropriate amount of water to dissolve, and stirring evenly to obtain the additive; the mass ratio of the premix to water is 1: (5-6).

5. The concrete suitable for high temperature construction environment according to claim 1, characterized in that: The concrete suitable for high-temperature construction environment includes the following components in parts by weight: 185 parts of cement, 70 parts of fly ash, 70 parts of mineral powder, 780 parts of machine-made sand, 1080 parts of crushed stone, 15 parts of manganese slag powder, 4.3 parts of ethylene-vinyl acetate copolymer, 10.7 parts of admixture, 130 parts of water, and 120 parts of ice cubes.

6. The concrete suitable for high temperature construction environment according to claim 1, characterized in that: The concrete suitable for high temperature construction environment also includes 1 to 3 parts of sodium molybdate.

7. A method for preparing concrete suitable for high temperature construction environment according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1: Mix cement, fly ash, mineral powder and manganese slag powder evenly to obtain a dry mix; Evenly mixing ethylene-vinyl acetate copolymer, additive, water and ice cubes to obtain a solid-liquid mixture; Step 2: Mix the machine-made sand, crushed stone and solid-liquid mixture evenly, then add the dry mix and stir evenly to obtain concrete suitable for high temperature construction environment.

8. The method for preparing concrete suitable for high temperature construction environment according to claim 7, characterized in that: The following steps are involved: Step 1: Mix cement, fly ash, mineral powder and manganese slag powder evenly to obtain a dry mix; Evenly mixing ethylene-vinyl acetate copolymer, additive, sodium molybdate, water and ice cubes to obtain a solid-liquid mixture; Step 2: Mix the machine-made sand, crushed stone and solid-liquid mixture evenly, then add the dry mix and stir evenly to obtain concrete suitable for high temperature construction environment.

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