Radiation-proof self-compacting concrete and method for preparing the same

Abstract

The application relates to a kind of radiation-proof self-compacting concrete and its preparation method in the technical field of concrete.The preparation raw materials of concrete include the following components according to weight parts: 100-300 parts of radiation-proof cement, 600-900 parts of crushed stone of barite, 50-150 parts of ludwigite, 7-18 parts of high-efficiency water reducing agent, 0.1-0.5 parts of sodium dioctyl succinate sulfonate, 0.05-0.2 parts of silicone resin polyether emulsion, 0.3-1 parts of slow-release defoamer, 80-130 parts of fly ash, 30-60 parts of slag and 160-250 parts of water, and the slow-release defoamer is hydrophobic white carbon black coated by sodium starch octenyl succinate and soluble soybean polysaccharide.The application forms a large number of stable bubbles in concrete by adding sodium dioctyl succinate sulfonate and silicone resin polyether emulsion, reduces the friction between raw material particles, thereby improving the fluidity of concrete and realizing self-compaction.

Description

Technical Field

[0001] This application relates to the field of concrete technology, and in particular to a radiation-resistant self-compacting concrete and its preparation method. Background Technology

[0002] Radiation-shielding concrete, also known as shielding concrete or radiation-shielding concrete, has a high density and can shield against gamma rays, X-rays, or neutron radiation. It is not easily penetrated by radiation and is therefore often used as a substitute for expensive radiation-shielding materials such as lead and steel. It is used for the protection of radioactive isotope equipment in nuclear reactors, particle accelerators, and industrial, agricultural, and scientific research departments.

[0003] Most radiation-shielding concrete currently on the market suffers from poor fluidity, easy bleeding, and easy segregation. Furthermore, due to the high aggregate density of radiation-shielding concrete, it is difficult to achieve self-leveling and self-compacting, requiring vibration during its molding process. However, during construction vibration, the concrete is prone to segregation, leading to uneven internal structure and resulting in low hardened strength and reduced radiation shielding performance.

[0004] Therefore, how to improve the fluidity of radiation-shielding concrete so that it can achieve self-compactment without vibration is an urgent problem to be solved. Summary of the Invention

[0005] To address the challenge of improving the fluidity of radiation-shielding concrete and enabling it to self-compact, this application provides a self-compacting radiation-shielding concrete and its preparation method. This application involves adding sodium dioctyl succinate sulfonate and silicone polyether emulsion to the concrete, which creates numerous stable air bubbles within the concrete, reducing frictional resistance between raw material particles and thus enhancing the concrete's fluidity and achieving self-compactment.

[0006] In the first aspect, this application provides a radiation-resistant self-compacting concrete, which adopts the following technical solution:

[0007] A radiation-resistant self-compacting concrete, wherein the raw materials for preparing the concrete, by weight, include the following components: 100-300 parts of radiation-resistant cement, 600-900 parts of barite crushed stone, 50-150 parts of boromagnesite, 700-1000 parts of iron tailings sand, 7-18 parts of high-efficiency water-reducing agent, 0.1-0.5 parts of sodium dioctyl succinate sulfonate, 0.05-0.2 parts of silicone polyether emulsion, 0.4-1.5 parts of slow-release defoamer, 80-130 parts of fly ash, 30-60 parts of slag, and 160-250 parts of water;

[0008] The slow-release defoamer is a hydrophobic silica coated with sodium octenyl succinate starch and soluble soybean polysaccharide.

[0009] By adopting the above technical solution, sodium dioctyl succinate sulfonate can generate a large number of bubbles when added to concrete. The silicone resin polyether emulsion gives the bubbles good elasticity and self-healing ability, and improves the structural stability of the bubbles. The combination of sodium dioctyl succinate sulfonate and silicone resin polyether emulsion forms a large number of stable bubbles in the early stage of concrete pouring, reduces the friction between the raw material particles, increases the fluidity of concrete, and achieves its self-densification.

[0010] However, during the later stages of concrete curing, the presence of air bubbles can affect the strength of the cured concrete. Therefore, the raw materials for preparing the concrete described in this application also include a slow-release defoamer. The use of a slow-release defoamer can effectively eliminate air bubbles present in the concrete during the later stages of pouring. Specifically, the slow-release defoamer in this application is a hydrophobic silica coated with sodium octenyl succinate starch and soluble soybean polysaccharide. In the early stages of pouring, the hydrophobic silica is not able to play a defoaming role because it is coated by the two water-soluble wall materials, sodium octenyl succinate starch and soluble soybean polysaccharide. In the later stages of pouring, as the sodium octenyl succinate starch and soluble soybean polysaccharide dissolve in water, the hydrophobic silica is exposed. The exposed hydrophobic silica particles attract the hydrophobic ends of sodium dioctyl succinate sulfonate on the surface of the air bubbles, turning the hydrophobic particles into hydrophilic particles and allowing them to enter the aqueous phase, causing the air bubbles to burst. Therefore, the slow-release defoamer added in this application enables the concrete to achieve self-densification while maintaining its strength.

[0011] In addition, high-efficiency water-reducing agents have a strong dispersing effect, which can reduce the yield shear stress of concrete mixtures and improve the rheological properties of concrete. On the other hand, they can effectively reduce the water-cement ratio, ensuring the mechanical properties and durability of hardened concrete. The mineral composition of fly ash consists of sponge glass and aluminosilicate glass microspheres. These spherical glass particles have smooth surfaces, small particle sizes, and dense textures, playing a certain lubricating role in concrete. The contact area between slag particles and cement particles, as well as between adjacent slag particles, is small, and the water-repellent effect of slag powder makes the adsorption of water-reducing agents weak. Therefore, the dual admixture of slag powder and fly ash can improve the fluidity and workability of concrete and reduce slump loss.

[0012] In some specific embodiments, the radiation-shielding cement is barium sulfate cement, the high-efficiency water-reducing agent is polycarboxylate water-reducing agent, and the particle size of the barite crushed stone is 20mm.

[0013] Preferably, the raw materials for preparing the concrete, by weight, include the following components: 150-250 parts of radiation-resistant cement, 700-850 parts of barite crushed stone, 80-120 parts of boromagnesite, 800-900 parts of iron tailings sand, 9-15 parts of high-efficiency water-reducing agent, 0.1-0.5 parts of sodium dioctyl succinate sulfonate, 0.05-0.2 parts of silicone resin polyether emulsion, 0.4-1.5 parts of slow-release defoamer, 90-120 parts of fly ash, 40-60 parts of slag, and 180-240 parts of water.

[0014] Preferably, the mass ratio of the sodium dioctyl succinate sulfonate to the silicone polyether emulsion is (1-4):1.

[0015] By adopting the above technical solution, the addition amounts of sodium dioctyl succinate sulfonate and silicone polyether emulsion are further adjusted to make the bubbles formed by sodium dioctyl succinate sulfonate in concrete more stable, thereby improving the fluidity of concrete in the early stage of pouring and achieving self-compacting of concrete.

[0016] In some preferred embodiments, the mass ratio of sodium dioctyl succinate sulfonate to the silicone polyether emulsion can be 2:1 or 3:1, etc.

[0017] Preferably, the total mass ratio of the sodium dioctyl succinate sulfonate and the silicone polyether emulsion to the sustained-release defoamer is 1:(1-2.5).

[0018] If the amount of slow-release defoamer added is too small, the effect of eliminating air bubbles in concrete will be poor, thus affecting the strength of concrete. If the amount of slow-release defoamer added is too large, it will increase the production cost of concrete and also affect the compressive strength of concrete.

[0019] In some preferred embodiments, the mass ratio of the total mass of the sodium dioctyl succinate sulfonate and the silicone polyether emulsion to the mass ratio of the sustained-release defoamer can be 1:1, 1:1.5, or 1:2, etc.

[0020] Preferably, the coating thickness of the sodium octenyl succinate starch and soluble soybean polysaccharide on the hydrophobic silica is 4-8 μm.

[0021] By adopting the above technical solution, when the thickness of the sodium octenyl succinate starch and soluble soybean polysaccharide coating on the outside of the hydrophobic silica is controlled within the above range, it can be ensured that the hydrophobic silica will not eliminate a large number of air bubbles in the early stage of concrete pouring, and it can also be ensured that the hydrophobic silica can eliminate harmful air bubbles in the concrete before the concrete is formed, thereby improving the fluidity of the concrete while ensuring the strength of the concrete.

[0022] In some preferred embodiments, the coating thickness of sodium octenyl succinate starch and soluble soybean polysaccharide on the hydrophobic silica can be 6 μm.

[0023] As a preferred embodiment, the preparation method of the sustained-release defoamer is as follows:

[0024] S1. Dissolve the sodium octenyl succinate starch and the soluble soybean polysaccharide in water to prepare a wall material mixture;

[0025] S2. Add methylglucose sesquistearate and the hydrophobic silica to the wall material mixture and mix evenly to obtain an emulsion.

[0026] S3. Spray dry the emulsion to obtain a slow-release defoamer.

[0027] By adopting the above technical solution, sodium octenyl succinate starch and soluble soybean polysaccharide are both water-soluble wall materials with strong water absorption. Among them, sodium octenyl succinate starch has a certain viscosity, and soluble soybean polysaccharide has good film-forming properties and stability. The combination of the two can form a stable microcapsule shell to coat the hydrophobic silica. By adjusting the spray drying conditions, the thickness of the microcapsule shell can be controlled, thereby controlling the time for the defoamer to take effect after the microcapsule shell dissolves in water.

[0028] In addition, methyl gluconate sesquistearate has excellent emulsifying and dispersing properties, which can improve the surface tension between various constituent phases in the emulsion, so as to form a uniform and stable dispersion system. Sodium octenyl succinate starch and soluble soybean polysaccharide can enhance the stability of the emulsion. Therefore, the combined use of the three can further enhance the dispersibility of hydrophobic silica in the wall material mixture, improve the encapsulation rate of microcapsule shells, reduce the possibility of hydrophobic silica playing a role in the early stage of pouring, and further improve the fluidity of concrete.

[0029] Preferably, the total content of sodium octenyl succinate starch and the soluble soybean polysaccharide in the wall material mixture is 2wt%-6wt%.

[0030] In some preferred embodiments, the total content of sodium octenyl succinate starch and the soluble soybean polysaccharide in the wall material mixture can be 3 wt% or 5 wt%, etc.

[0031] By adopting the above technical solution, since sodium octenyl succinate starch is viscous, if too much sodium octenyl succinate starch and soluble soybean polysaccharide are added, the wall material mixture will be too viscous, which is not conducive to the dispersion of hydrophobic silica, increases costs and affects the coating effect; if too little sodium octenyl succinate starch and soluble soybean polysaccharide are added, it cannot be guaranteed that the hydrophobic silica will be completely coated, thus affecting the fluidity of concrete.

[0032] In some specific embodiments, the mass ratio of sodium octenyl succinate starch to the soluble soybean polysaccharide can be 1:(2-3), for example, 1:2 or 1:3.

[0033] Preferably, the mass ratio of the methylglucose sesquistearate to the hydrophobic silica is (1-4):1.

[0034] By adopting the above technical solution and further adjusting the amount of methylglucose sesquistearate and the hydrophobic silica added, it is beneficial to improve the uniformity and stability of the emulsion, thereby ensuring the coating effect of the hydrophobic silica.

[0035] In some preferred embodiments, the mass ratio of the methylglucose sesquistearate to the hydrophobic silica can be 2:1 or 3:1, etc.

[0036] Preferably, the mass-to-volume ratio of the hydrophobic silica and the wall material mixture is 1:(40-100).

[0037] By adopting the above technical solution, the mass-volume ratio of the hydrophobic silica and the wall material mixture is controlled within the above range, which is conducive to the more uniform dispersion of the hydrophobic silica in the wall material mixture and further improves the coating effect of the hydrophobic silica.

[0038] In some preferred embodiments, the mass-to-volume ratio of the hydrophobic silica and the wall material mixture can be 1:50 or 1:100, etc.

[0039] Secondly, this application provides a method for preparing radiation-resistant self-compacting concrete, employing the following technical solution:

[0040] A method for preparing radiation-resistant self-compacting concrete includes the following steps:

[0041] S1. Mix the radiation-proof cement, barite crushed stone, boromagnesia stone, iron tailings sand, high-efficiency water-reducing agent, sodium dioctyl succinate sulfonate, silicone resin polyether emulsion, fly ash, slag and water evenly to prepare premixed concrete.

[0042] S2. Mix the premixed concrete with the slow-release defoamer for 10-20 seconds to obtain radiation-proof self-compacting concrete.

[0043] By adopting the above technical solution, the raw materials other than the slow-release defoamer are mixed first, so that sodium dioctyl succinate sulfonate forms a large number of micro bubbles in the premixed concrete. Then, the slow-release defoamer is added and mixed for a short time to avoid the water-soluble microcapsule shells from dissolving or breaking during the mixing process, which would cause the hydrophobic silica to be exposed prematurely. This improves the fluidity of the concrete in the early stage of pouring and ensures the self-compacting of the concrete.

[0044] In summary, this application includes at least one of the following beneficial technical effects:

[0045] 1. This application uses sodium dioctyl succinate sulfonate and silicone polyether emulsion in combination to form a large number of stable microbubbles in the concrete, which can reduce the friction between the raw material particles, thereby improving the fluidity of the concrete and achieving self-compacting of the concrete.

[0046] 2. Using sodium octenyl succinate starch and soluble soybean polysaccharide as a wall material to coat hydrophobic silica ensures that the hydrophobic silica does not play a role in the early stage of concrete pouring, thus maintaining the fluidity of the concrete. When sodium octenyl succinate starch and soluble soybean polysaccharide dissolve in water, the hydrophobic silica will eliminate air bubbles in the concrete, preventing the formation of a large number of pores during the molding process, thereby improving the strength of the concrete.

[0047] 3. Sodium octenyl succinate starch and soluble soybean polysaccharides can both improve the stability of the emulsion. When combined with methyl glucose sesquistearate, they can improve the dispersibility of the components in the emulsion and further enhance the coating effect of hydrophobic silica, thereby ensuring the fluidity of concrete. Detailed Implementation

[0048] To make this application easier to understand, the following detailed description will be provided with reference to embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of application of this application. Unless otherwise specified, the raw materials or components used in this application can be obtained commercially or by conventional methods.

[0049] Raw material source:

[0050] Barium sulfate cement was purchased from Dongguan Shengkang Metal Materials Co., Ltd.; polycarboxylate superplasticizer was purchased from Wuhan Runxingyuan Technology Co., Ltd.; sodium dioctyl succinate was purchased from Hubei Watson Chemical Technology Co., Ltd.; silicone polyether emulsion was purchased from Qingdao Tengyun Chemical Technology Co., Ltd.; soluble soybean polysaccharide was purchased from Shandong Siyang Biotechnology Co., Ltd.; and hydrophobic silica HDK-H30 was purchased from Shizhong Mingzhi Chemical (Shanghai) Co., Ltd.

[0051] Preparation Example 1:

[0052] The raw materials and their amounts for preparing the sustained-release defoamer are shown in Table 1. The preparation steps of the sustained-release defoamer are as follows: Sodium octenyl succinate starch and soluble soybean polysaccharide are dissolved in water and stirred evenly to obtain a wall material mixture. Then, hydrophobic silica and methyl gluconate sesquistearate are added to the wall material mixture and mixed evenly to obtain an emulsion. The emulsion is homogenized and dispersed using a homogenizer, and then sprayed, dried, and granulated in a spray dryer to obtain the sustained-release defoamer. The inlet air temperature is 150℃, the outlet air temperature is 120℃, the compressed air flow rate is 650L / h, and the feed rate is 6ml / min. In the obtained sustained-release defoamer, the coating thickness of sodium octenyl succinate starch and soluble soybean polysaccharide on the outside of the hydrophobic silica is 6μm.

[0053] The mass ratio of sodium octenyl succinate starch to soluble soybean polysaccharide is 1:2, the total content of sodium octenyl succinate starch and soluble soybean polysaccharide in the wall material mixture is 3wt%, the mass-volume ratio of hydrophobic silica to the wall material mixture is 1:50, and the mass ratio of methyl glucose sesquistearate to hydrophobic silica is 2:1.

[0054] Table 1. Amounts of each component added in Preparation Examples 1-6

[0055]

[0056]

[0057] Preparation Example 2

[0058] The raw materials and their amounts for preparing the sustained-release defoamer are shown in Table 1. The difference between Preparation Example 2 and Preparation Example 1 is that the mass ratio of sodium octenyl succinate starch to soluble soybean polysaccharide is 1:3, and the preparation method is the same as that of Preparation Example 1.

[0059] Preparation Example 3

[0060] The raw materials and their amounts for preparing the sustained-release defoamer are shown in Table 1. The difference between Preparation Example 3 and Preparation Example 1 is that the mass ratio of sodium octenyl succinate starch and soluble soybean polysaccharide is 1:1, and the preparation method is the same as that of Preparation Example 1.

[0061] Preparation Example 4

[0062] The raw materials and their amounts for preparing the sustained-release defoamer are shown in Table 1. The difference between Preparation Example 4 and Preparation Example 1 is that the total content of sodium octenyl succinate starch and soluble soybean polysaccharide in the wall material mixture is 5 wt%, while the preparation method is the same as in Preparation Example 1.

[0063] Preparation Example 5

[0064] The raw materials and their amounts for preparing the slow-release defoamer are shown in Table 1. The difference between Preparation Example 5 and Preparation Example 1 is that the mass-to-volume ratio of the hydrophobic silica and the wall material mixture is 1:100, and the preparation method is the same as that of Preparation Example 1.

[0065] Preparation Example 6

[0066] The raw materials and their amounts for preparing the sustained-release defoamer are shown in Table 1. The difference between Preparation Example 6 and Preparation Example 1 is that the mass ratio of methylglucose sesquistearate and hydrophobic silica is 3:1, and the preparation method is the same as that of Preparation Example 1.

[0067] Preparation Example 7

[0068] The difference between Preparation Example 7 and Preparation Example 6 is that the spray drying conditions were adjusted so that the coating thickness of sodium octenyl succinate starch and soluble soybean polysaccharide on the hydrophobic silica in the prepared slow-release defoamer was 10 μm, and the rest was the same as in Preparation Example 6.

[0069] Example 1

[0070] The raw materials for preparing the radiation-proof self-compacting concrete in Example 1 were: 200 kg of barium sulfate cement, 750 kg of barite crushed stone, 100 kg of boromagnesite, 850 kg of iron tailings sand, 12 kg of polycarboxylate superplasticizer, 0.4 kg of sodium dioctyl succinate sulfonate, 0.2 kg of silicone polyether emulsion, 0.6 kg of the slow-release defoamer prepared in Example 1, 100 kg of fly ash, 50 kg of slag, and 210 kg of water. The mass ratio of sodium dioctyl succinate sulfonate to silicone polyether emulsion was 2:1, and the total mass ratio of sodium dioctyl succinate sulfonate and silicone polyether emulsion to the slow-release defoamer was 1:1.

[0071] The preparation method of radiation-proof self-compacting concrete is as follows: First, barium sulfate cement, barite crushed stone, boron magnesium stone, iron tailings sand, polycarboxylate superplasticizer, sodium dioctyl succinate sulfonate, silicone resin polyether emulsion, fly ash, slag and water are mixed evenly to obtain premixed concrete. Then, a slow-release defoamer is added to the premixed concrete and stirred for 15 seconds to obtain radiation-proof self-compacting concrete.

[0072] Example 2

[0073] The raw materials for preparing the radiation-proof self-compacting concrete in Example 2 are: 200 kg of barium sulfate cement, 750 kg of barite crushed stone, 100 kg of boromagnesite, 850 kg of iron tailings sand, 12 kg of polycarboxylate superplasticizer, 0.45 kg of sodium dioctyl succinate sulfonate, 0.15 kg of silicone polyether emulsion, 0.6 kg of the slow-release defoamer obtained in Preparation Example 1, 100 kg of fly ash, 50 kg of slag, and 210 kg of water. The mass ratio of sodium dioctyl succinate sulfonate to silicone polyether emulsion is 3:1, and the mass ratio of the total mass of sodium dioctyl succinate sulfonate and silicone polyether emulsion to the mass ratio of the slow-release defoamer is 1:1.

[0074] The rest is the same as in Example 1.

[0075] Example 3

[0076] The raw materials for preparing the radiation-proof self-compacting concrete in Example 3 were: 200 kg of barium sulfate cement, 750 kg of barite crushed stone, 100 kg of boromagnesite, 850 kg of iron tailings sand, 12 kg of polycarboxylate superplasticizer, 0.45 kg of sodium dioctyl succinate sulfonate, 0.15 kg of silicone polyether emulsion, 0.9 kg of the slow-release defoamer obtained in Preparation Example 1, 100 kg of fly ash, 50 kg of slag, and 210 kg of water. The mass ratio of sodium dioctyl succinate sulfonate to silicone polyether emulsion was 3:1, and the mass ratio of the total mass of sodium dioctyl succinate sulfonate and silicone polyether emulsion to the mass ratio of the slow-release defoamer was 1:1.5.

[0077] The rest is the same as in Example 1.

[0078] Example 4

[0079] The raw materials for preparing the radiation-proof self-compacting concrete in Example 4 are: 200 kg of barium sulfate cement, 750 kg of barite crushed stone, 100 kg of boromagnesite, 850 kg of iron tailings sand, 12 kg of polycarboxylate superplasticizer, 0.45 kg of sodium dioctyl succinate sulfonate, 0.15 kg of silicone polyether emulsion, 1.2 kg of the slow-release defoamer obtained in Preparation Example 1, 100 kg of fly ash, 50 kg of slag, and 210 kg of water. The mass ratio of sodium dioctyl succinate sulfonate to silicone polyether emulsion is 3:1, and the mass ratio of the total mass of sodium dioctyl succinate sulfonate and silicone polyether emulsion to the mass ratio of the slow-release defoamer is 1:2.

[0080] The rest is the same as in Example 1.

[0081] Examples 5-10

[0082] The difference between Examples 5-10 and Example 3 is that the sustained-release defoamer is the same as that prepared in Examples 2-7, while the rest is the same as in Example 3.

[0083] Example 11

[0084] The difference between Example 11 and Example 9 is that, in the preparation process of the radiation-resistant self-compacting concrete, the premixed concrete and the slow-release defoamer are stirred and mixed for 1 minute to obtain the radiation-resistant self-compacting concrete. The rest is the same as in Example 9.

[0085] Comparative Example 1

[0086] The difference between Comparative Example 1 and Example 9 is that silicone resin polyether emulsion was not added to the raw materials for preparing radiation-proof self-compacting concrete, and the amount of sodium dioctyl succinate sulfonate added was adjusted to 0.6 kg. The rest is the same as in Example 10.

[0087] Comparative Example 2

[0088] The difference between Comparative Example 2 and Example 9 is that no slow-release defoamer was added to the raw materials for preparing radiation-proof self-compacting concrete; otherwise, they are the same as in Example 9.

[0089] Comparative Example 3

[0090] The difference between Comparative Example 3 and Example 9 is that in the raw materials for preparing radiation-proof self-compacting concrete, an equal amount of hydrophobic silica is used instead of a slow-release defoamer, while the rest is the same as in Example 9.

[0091] Test case

[0092] The radiation-resistant self-compacting concretes prepared in Examples 1-11 and Comparative Examples 1-3 were subjected to performance tests, specifically including 28-day compressive strength, slump flow, J-ring spread, and spread time T50. The 28-day compressive strength was tested according to GB / T50081-2002 "Standard for Test Methods of Mechanical Properties of Ordinary Concrete," the slump flow was tested according to GB / T50080-2002 "Standard for Test Methods of Performance of Ordinary Concrete Mixtures," and the J-ring spread and spread time T50 were tested according to JGJ / T283-2012 "Technical Specification for Application of Self-Compacting Concrete." The test results are shown in Table 2.

[0093] Table 2

[0094] 28-day compressive strength / MPa Collapse spread / mm J-ring expansion / mm Extended time T50 / s Example 1 42.0 622 601 5.2 Example 2 41.7 632 618 5.0 Example 3 44.5 638 622 4.9 Example 4 43.1 603 586 5.5 Example 5 42.3 600 587 5.5 Example 6 39.8 616 603 5.3 Example 7 38.4 613 601 5.3 Example 8 44.1 635 620 4.9 Example 9 47.7 672 659 4.4 Example 10 34.2 659 647 4.6 Example 11 45.0 567 554 6.1 Comparative Example 1 41.1 582 570 5.8 Comparative Example 2 31.4 667 654 4.7 Comparative Example 3 42.8 456 439 6.6

[0095] According to the test results in Table 2, the 28-day compressive strength of the radiation-proof self-compacting concrete prepared in Examples 1-11 and Comparative Examples 1-3 is 31.4-47.7 MPa, the slump spread is 456-672 mm, the J-ring spread is 439-659 mm, and the spread time T50 is 4.4-6.6 s.

[0096] The test results from Example 1 and Comparative Examples 1-3 show that the combination of sodium dioctyl succinate sulfonate and silicone polyether emulsion, when added to concrete, can form a large number of stable air bubbles within the concrete, reducing the friction between the raw material particles and increasing the fluidity of the concrete. Furthermore, the addition of a slow-release defoamer prevents the elimination of a large number of air bubbles in the early stages of pouring, thus avoiding interference with the self-compacting of the concrete. Simultaneously, it can also eliminate harmful air bubbles during the concrete forming process, ensuring the strength of the concrete.

[0097] The test results of Examples 1 and 2 show that when the mass ratio of sodium dioctyl succinate sulfonate to silicone polyether emulsion is 3:1, the synergistic effect between the two is better, the bubbles formed in the concrete are more stable, and the fluidity of the concrete is further improved.

[0098] As can be seen from the test results of Examples 2-4, when the total mass ratio of sodium dioctyl succinate sulfonate and silicone polyether emulsion to the slow-release defoamer is 1:1.5, the slow-release defoamer can more thoroughly eliminate harmful bubbles and ensure the strength of concrete.

[0099] As can be seen from the test results of Examples 3 and 5-7, when the content of sodium octenyl succinate starch and soluble soybean polysaccharide in the wall material mixture is 3wt%, and the mass ratio of sodium octenyl succinate starch to soluble soybean polysaccharide is 1:2, the two can form a stable microcapsule shell on the surface of hydrophobic silica, ensuring its effect in the concrete pouring and molding process.

[0100] The test results of Examples 3 and 8 show that when the mass-volume ratio of the hydrophobic silica and the wall material mixture is 1:50, the coating effect of the hydrophobic silica is better and the production cost is lower. The wall material can be uniformly coated on the surface of the hydrophobic silica, which further ensures the effect of the hydrophobic silica in the concrete pouring and molding process.

[0101] The test results of Examples 3 and 9 show that when the mass ratio of methylglucose sesquistearate to hydrophobic silica is 3:1, it is more conducive to improving the uniformity and stability of the emulsion, thereby improving the coating effect of hydrophobic silica.

[0102] The test results of Examples 9 and 10 show that when the coating thickness of sodium octenyl succinate starch and soluble soybean polysaccharide on the outside of hydrophobic silica in the slow-release defoamer is 6 μm, it can ensure that the hydrophobic silica will not eliminate a large number of air bubbles in the early stage of concrete pouring. In the later stage of pouring and molding process, sodium octenyl succinate starch and soluble soybean polysaccharide can dissolve, exposing the hydrophobic silica and eliminating the harmful air bubbles, thus ensuring the strength of the concrete.

[0103] As can be seen from the test results of Examples 9 and 11, during the concrete preparation process, mixing the premixed concrete with the slow-release defoamer for 15 seconds avoids the dissolution or rupture of the microcapsule shell of the slow-release defoamer during the long mixing process, which would lead to the premature exposure of the hydrophobic silica. This ensures the fluidity of the concrete in the early stage of pouring and achieves the self-densification of the concrete.

[0104] It should be noted that the embodiments described above are only for explaining this application and do not constitute any limitation on this application. This application has been described with reference to typical embodiments, but it should be understood that the terms used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to this application within the scope of the claims, and revisions can be made to the invention without departing from the scope and spirit of this application. Although the application described herein relates to specific methods, materials, and embodiments, it does not mean that this application is limited to the specific examples disclosed herein; on the contrary, this application can be extended to all other methods and applications with the same function.

Claims

1. A radiation-resistant self-compacting concrete, characterized in that: The raw materials for preparing the concrete, by weight, include the following components: 100-300 parts of radiation-resistant cement, 600-900 parts of barite crushed stone, 50-150 parts of boromagnesite, 700-1000 parts of iron tailings sand, 7-18 parts of high-efficiency water-reducing agent, 0.1-0.5 parts of sodium dioctyl succinate sulfonate, 0.05-0.2 parts of silicone resin polyether emulsion, 0.4-1.5 parts of slow-release defoamer, 80-130 parts of fly ash, 30-60 parts of slag, and 160-250 parts of water; The slow-release defoamer is a hydrophobic silica coated with sodium octenyl succinate starch and soluble soybean polysaccharide; The coating thickness of sodium octenyl succinate starch and soluble soybean polysaccharide on the hydrophobic silica is 4-8 μm. The preparation method of the sustained-release defoamer is as follows: S1. Dissolve the sodium octenyl succinate starch and the soluble soybean polysaccharide in water to prepare a wall material mixture; S2. Add methylglucose sesquistearate and the hydrophobic silica to the wall material mixture and mix evenly to obtain an emulsion. S3. Spray-dry the emulsion to obtain a slow-release defoamer; The total content of sodium octenyl succinate starch and soluble soybean polysaccharide in the wall material mixture is 2wt%-6wt%.

2. The radiation-resistant self-compacting concrete according to claim 1, characterized in that: The raw materials for preparing the concrete, by weight, include the following components: 150-250 parts of radiation-resistant cement, 700-850 parts of barite crushed stone, 80-120 parts of boromagnesite, 800-900 parts of iron tailings sand, 9-15 parts of high-efficiency water-reducing agent, 0.1-0.5 parts of sodium dioctyl succinate sulfonate, 0.05-0.2 parts of silicone resin polyether emulsion, 0.4-1.5 parts of slow-release defoamer, 90-120 parts of fly ash, 40-60 parts of slag, and 180-240 parts of water.

3. The radiation-resistant self-compacting concrete according to claim 1, characterized in that: The mass ratio of sodium dioctyl succinate sulfonate to the silicone polyether emulsion is (1-4):

1.

4. The radiation-resistant self-compacting concrete according to claim 1, characterized in that: The total mass ratio of the sodium dioctyl succinate sulfonate and the silicone polyether emulsion to the sustained-release defoamer is 1:(1-2.5).

5. The radiation-resistant self-compacting concrete according to claim 1, characterized in that: The mass ratio of the methylglucose sesquistearate to the hydrophobic silica is (1-4):

1.

6. The radiation-resistant self-compacting concrete according to claim 1, characterized in that: The mass-to-volume ratio of the hydrophobic silica and the wall material mixture is 1 kg: (40-100) L.

7. A method for preparing radiation-resistant self-compacting concrete as described in any one of claims 1-6, characterized in that: The following steps are included: S1. Mix the radiation-proof cement, barite crushed stone, boromagnesia stone, iron tailings sand, high-efficiency water-reducing agent, sodium dioctyl succinate sulfonate, silicone resin polyether emulsion, fly ash, slag and water evenly to prepare premixed concrete. S2. Mix the premixed concrete with the slow-release defoamer for 10-20 seconds to obtain radiation-proof self-compacting concrete.

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