A concrete applicable to high-temperature construction environments and its preparation method

Abstract

The present invention relates to the technical field of concrete, and specifically discloses a concrete suitable for high-temperature construction environments and a preparation method thereof. A concrete suitable for high-temperature construction environments includes 150-200 parts of cement, 60-75 parts of fly ash, 60-80 parts of slag powder, 720-800 parts of manufactured 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 an 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 allylsulfonic acid sodium in water. The concrete of the present application can not only maintain good workability and strength development under high-temperature conditions, but also has excellent crack resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete, and in particular to a concrete applicable to 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 is easily evaporated, resulting in a faster shrinkage rate on the surface of the concrete than in the deep layer, causing internal and external shrinkage differences, and thus cracks. At the same time, high temperature may cause changes in the internal structure of the concrete, increasing the hydration reaction rate of the concrete and shortening the hardening time, which affects the shrinkage characteristics of the concrete. Therefore, it is necessary to further improve the concrete formula to adapt to high-temperature construction environments 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 under high-temperature construction environments, the present invention provides a concrete applicable to high-temperature construction environments and a preparation method thereof. The concrete of the present application can not only maintain good workability and strength development under high-temperature conditions, but also has excellent crack resistance.

[0004] In a first aspect, a concrete applicable to high-temperature construction environments provided by the present application adopts the following technical solution: A concrete applicable to high-temperature construction environments includes the following raw materials in parts by weight: 150-200 parts of cement, 60-75 parts of fly ash, 60-80 parts of slag powder, 720-800 parts of manufactured 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 an 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 allylsulfonic acid sodium in water.

[0005] In the above technical solution, by adding a specific proportion of ice cubes to the concrete, the present application can effectively reduce the initial temperature of the concrete, thereby slowing down the evaporation rate of the moisture on the surface of the concrete in a high-temperature environment. By introducing manganese slag powder and ethylene-vinyl acetate copolymer, the present application can further improve the crack resistance and durability of the concrete. By introducing an admixture prepared from hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether, and allylsulfonic acid sodium, 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 the concrete, and allylsulfonic acid sodium can enhance the cohesiveness of the concrete. The synergistic effect of these three components enables the concrete to maintain good workability under high-temperature environments and further improves the crack resistance of the concrete.

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

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

[0008] In the above technical solution, by limiting the weight ratio of hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether, and sodium allylsulfonate, the present application can ensure that the performance of concrete is more stable in a high-temperature construction environment, enabling the concrete to have better workability and strength development under high-temperature conditions, and effectively reducing the generation of cracks at the same time.

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

[0010] In the above technical solution, by precisely controlling the ratio of the premix to water, the present application can obtain an admixture with stable performance, ensuring the uniform distribution and effective action of the admixture in concrete, and thus better exerting its functions of water retention, flow increase, setting time extension, and cohesion enhancement.

[0011] Preferably, the concrete applicable to a high-temperature construction environment includes the following components in parts by weight: 185 parts of cement, 70 parts of fly ash, 70 parts of slag powder, 780 parts of manufactured 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.

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

[0013] Preferably, the concrete applicable to a high-temperature construction environment further includes 1 - 3 parts of sodium molybdate.

[0014] In the above technical solution, by adding sodium molybdate to the concrete, the present application can further improve the high-temperature resistance of the concrete. As an inorganic salt, sodium molybdate can act together with the admixture, further improve the water retention of the concrete, inhibit the excessive evaporation of internal water in the concrete, improve the internal microstructure of the concrete, enhance its adaptability to temperature changes, and reduce the probability of crack generation while improving the workability of the concrete.

[0015] In a second aspect, a method for preparing concrete applicable to a high-temperature construction environment provided by the present application adopts the following technical solution:

[0016] A method for preparing concrete applicable to a high-temperature construction environment includes the following steps:

[0017] Step 1: Mix cement, fly ash, slag 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;

[0018] Step 2: Mix manufactured sand, crushed stone, and the solid-liquid mixture evenly, then add the dry mixture and stir evenly to prepare concrete applicable to a high-temperature construction environment.

[0019] Preferably, it includes the following steps:

[0020] Step 1: Mix cement, fly ash, slag powder, and manganese slag powder evenly to obtain a dry mixture; mix ethylene-vinyl acetate copolymer, admixture, sodium molybdate, water, and ice cubes evenly to obtain a solid-liquid mixture;

[0021] Step 2: Mix manufactured sand, crushed stone, and the solid-liquid mixture evenly, then add the dry mixture and stir evenly to prepare concrete applicable to a high-temperature construction environment.

[0022] In the above technical solution, through the above preparation method, the present application can ensure that the performance of the concrete is more stable in a high-temperature construction environment, enabling the concrete to have better workability and strength development under high-temperature conditions, and effectively reducing the generation of cracks.

[0023] In summary, the present application includes at least one of the following beneficial technical effects:

[0024] 1. By adding ice cubes to the concrete, the present application achieves the effect of regulating the temperature of the concrete and slowing down the evaporation of water in the concrete. By introducing manganese slag powder and ethylene-vinyl acetate copolymer, the crack resistance and durability of the concrete are enhanced. By using the admixture, through the synergistic effect of hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether, and allylsulfonic acid sodium, not only the workability of the concrete is improved, but also the development of the concrete strength is promoted, ensuring the stable performance of the concrete in a high-temperature environment.

[0025] 2. By adding sodium molybdate, sodium molybdate interacts with the admixture of the present application, which helps to improve the internal microstructure of the concrete, enhance its adaptability to temperature changes, thereby reducing the internal stress caused by temperature fluctuations and reducing the generation of cracks, further optimizing the stability and crack resistance of the concrete under high-temperature construction conditions. Detailed implementation mode

[0026] To better illustrate the purpose, technical solution and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0027] Preparation Example 1

[0028] An admixture, the preparation raw materials include 1 kg of hydroxypropyl cellulose, 1 kg of fatty alcohol polyoxyethylene ether, 0.8 kg of sodium allylsulfonate and 14 kg of water.

[0029] Among them, the hydroxypropyl cellulose was purchased from Anhui Longyang Environmental Protection Technology Co., Ltd.

[0030] Among them, the fatty alcohol polyoxyethylene ether was purchased from Xingtai Xinlanxing Technology Co., Ltd., product name: penetrant JFC.

[0031] Among them, the sodium allylsulfonate was purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd.

[0032] Among them, the preparation method of the admixture is as follows: mix hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allylsulfonate to obtain a premix, then add water for dissolution, and stir evenly to obtain the admixture.

[0033] Preparation Example 2

[0034] An admixture, different from Preparation Example 1, the preparation raw materials include 1 kg of hydroxypropyl cellulose, 0.7 kg of fatty alcohol polyoxyethylene ether, 0.5 kg of sodium allylsulfonate and 13.2 kg of water.

[0035] Among them, the preparation method of the admixture is as follows: mix hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allylsulfonate to obtain a premix, then add water for dissolution, and stir evenly to obtain the admixture.

[0036] Preparation Example 3

[0037] An admixture, different from Preparation Example 1, the preparation raw materials include 1 kg of hydroxypropyl cellulose, 0.9 kg of fatty alcohol polyoxyethylene ether, 0.7 kg of sodium allylsulfonate and 14.3 kg of water.

[0038] Among them, the preparation method of the admixture is as follows: mix hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allylsulfonate to obtain a premix, then add water for dissolution, and stir evenly to obtain the admixture.

[0039] Comparative Preparation Example 1

[0040] An admixture, different from Preparation Example 1, the hydroxypropyl cellulose was replaced with polyacrylamide in equal amount.

[0041] Comparative Preparation Example 2

[0042] An admixture, different from Preparation Example 1, is that fatty alcohol polyoxyethylene ether is replaced with sodium lauryl sulfate in equal amount.

[0043] Comparative Preparation Example 3

[0044] An admixture, different from Preparation Example 1, is that sodium allylsulfonate is replaced with sodium lauryl sulfonate in equal amount.

[0045] Example 1

[0046] A concrete applicable to high-temperature construction environment, comprising 150 kg of cement, 60 kg of fly ash, 60 kg of blast furnace slag powder, 720 kg of manufactured 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 cubes.

[0047] Among them, the cement is ordinary Portland cement PO42.5 of Southern Cement.

[0048] Among them, the fly ash is secondary fly ash.

[0049] Among them, the blast furnace slag powder is of S95 grade.

[0050] Among them, the fineness modulus of the manufactured sand is 2.8.

[0051] Among them, the crushed stone is continuously graded crushed stone with a particle size of 5 - 25 mm.

[0052] Among them, the manganese slag powder is purchased from Anyang Xinhai Metallurgical Refractory Co., Ltd. and the particle size is less than 0.075 mm.

[0053] Among them, the ethylene-vinyl acetate copolymer is purchased from Jinan Xiangfeng Weiye Chemical Co., Ltd., CAS No.: 24937-78-8.

[0054] Among them, the admixture is prepared from Preparation Example 1.

[0055] Among them, the sodium molybdate is purchased from Wuhan Jiyesheng Chemical Co., Ltd.

[0056] Among them, the preparation method of the concrete applicable to high-temperature construction environment includes the following steps:

[0057] Step 1: Mix the cement, fly ash, blast furnace slag powder, and manganese slag powder evenly to obtain a dry mixture; mix the ethylene-vinyl acetate copolymer, admixture, sodium molybdate, water, and ice cubes evenly to obtain a solid-liquid mixture.

[0058] Step 2: Mix the manufactured sand, crushed stone, and the solid-liquid mixture evenly, and then add the dry mixture and stir evenly to prepare the concrete applicable to high-temperature construction environment.

[0059] Example 2

[0060] A kind of concrete applicable to high-temperature construction environment, which is different from that of Example 1 in that it includes 200 kg of cement, 75 kg of fly ash, 80 kg of slag powder, 800 kg of manufactured 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 cubes.

[0061] Among them, the admixture is prepared from Preparation Example 2.

[0062] Example 3

[0063] A kind of concrete applicable to high-temperature construction environment, which is different from that of Example 1 in that it includes 185 kg of cement, 70 kg of fly ash, 70 kg of slag powder, 780 kg of manufactured sand, 1080 kg of crushed stone, 15 kg of manganese slag powder, 4.3 kg of ethylene-vinyl acetate copolymer, 10.7 kg of admixture, 1 kg of sodium molybdate, 130 kg of water, and 120 kg of ice cubes.

[0064] Among them, the admixture is prepared from Preparation Example 3.

[0065] Example 4

[0066] A kind of concrete applicable to high-temperature construction environment, which is different from that of Example 3 in that it does not contain sodium molybdate.

[0067] Among them, the preparation method of the concrete applicable to high-temperature construction environment includes the following steps:

[0068] Step 1: Mix the cement, fly ash, slag powder, and manganese slag powder evenly to obtain a dry mixture; mix the ethylene-vinyl acetate copolymer, admixture, water, and ice cubes evenly to obtain a solid-liquid mixture.

[0069] Step 2: Mix the manufactured sand, crushed stone, and solid-liquid mixture evenly, and then add the dry mixture and stir evenly to prepare the concrete applicable to high-temperature construction environment.

[0070] Comparative Example 1

[0071] A kind of concrete applicable to high-temperature construction environment, which is different from that of Example 1 in that the admixture is prepared from Comparative Preparation Example 1.

[0072] Comparative Example 2

[0073] A kind of concrete applicable to high-temperature construction environment, which is different from that of Example 1 in that the admixture is prepared from Comparative Preparation Example 2.

[0074] Comparative Example 3

[0075] A kind of concrete applicable to high-temperature construction environment, which is different from that of Example 1 in that the admixture is prepared from Comparative Preparation Example 3.

[0076] Comparative Example 4

[0077] A kind of concrete applicable to high-temperature construction environment, different from Example 1 in that the manganese slag powder is replaced with slag in equal amount.

[0078] Comparative Example 5

[0079] A kind of concrete applicable to high-temperature construction environment, different from Example 1 in that the ethylene-vinyl acetate copolymer is replaced with redispersible latex powder in equal amount.

[0080] Performance verification test environment: 35°C. Under other conditions, according to GB / T 50080—2016 Standard Test Methods for Performance of Ordinary Concrete Mixtures, the initial slump, 1h slump, initial setting time and final setting time of the concrete are detected. According to GB / T 50081—2019 Standard Test Methods for Mechanical Properties of Ordinary Concrete, the compressive strength of the concrete at 28d is detected, and the average number of surface cracks within 1.5h after the concrete is poured is counted.

[0081] The above test results are shown in Table 1.

[0082] Table 1:

[0083]

[0084] Specifically combined with Table 1, it can be analyzed that the concrete applicable to 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 surface crack number.

[0085] Specifically combined with Example 1 and Comparative Examples 1-3 for analysis, different admixtures are used in Comparative Examples 1-3. Example 1 shows good performance in terms of initial slump, 1h slump, initial setting time, final setting time, 28d compressive strength and surface crack number. Thus, it can be seen that through the synergistic effect of hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and allylsulfonic acid sodium, the present application can significantly improve the workability of concrete, promote the development of concrete strength, and ensure the performance stability of concrete in high-temperature environment.

[0086] Specifically combined with Example 1 and Comparative Examples 4-5 for analysis, the manganese slag powder and ethylene-vinyl acetate copolymer are replaced respectively in Comparative Examples 4-5. Example 1 shows good performance in terms of initial slump, 1h slump, initial setting time, final setting time, 28d compressive strength and surface crack number. Thus, it can be seen that by introducing manganese slag powder and ethylene-vinyl acetate copolymer into the concrete, the present application enhances the crack resistance of the concrete.

[0087] Specifically, in combination with Example 3 and Example 4, it is analyzed that compared with Example 4, sodium molybdate was added in the preparation process of Example 3. Example 3 showed good performance in terms of initial slump, 1h slump, initial setting time, final setting time, 28d compressive strength, and the number of surface cracks. Thus, it can be seen that by further adding sodium molybdate to the concrete, the combined action of sodium molybdate and the admixture of the present application can further optimize the stability and crack resistance of the concrete under high-temperature construction conditions.

[0088] This specific embodiment is only an interpretation of the present application and does not limit the present application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

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; The weight ratio of hydroxypropyl cellulose, fatty alcohol polyoxyethylene ether and sodium allyl sulfonate is 1: (0.7-1): (0.5-0.8); 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 to obtain the additive; the mass ratio of the premix to water is 1: (5-6); The concrete suitable for high temperature construction environment also includes 1 to 3 parts of sodium molybdate.

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 1:0.9:0.

7.

3. 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.

4. A method for preparing concrete suitable for high temperature construction environment according to any one of claims 1 to 3, 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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