Anti-burst and anti-impact sacrificial concrete and preparation method thereof

Abstract

The invention provides anti-burst and anti-impact sacrificial concrete and a preparation method thereof. The sacrificial concrete is prepared from the following components in parts by weight: 600 to 700 parts of cement, 250 to 350 parts of superfine fly ash, 100 to 150 parts of silica fume, 900 to 1100 parts of quartz sand, 70 to 120 parts of barium ferrite, 140 to 170 parts of steel fiber, 4 to 20 parts of sisal fiber, 193 to 213 parts of water and 15 to 20 parts of water reducing agent. The preparation method comprises the following steps: sequentially mixing and stirring the raw materials, pouring, forming and curing. The sacrificial concrete disclosed by the invention has good sacrificial property, and the water content of raw materials is lower than 5%, so that the hydrogen yield in the interaction process of a reactor core melt and a sacrificial material is reduced; and the sisal hemp is heated to form gaps and channels, so that the high-temperature bursting resistance is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of special concrete, in particular to a blast-resistant and impact-resistant sacrificial concrete and a preparation method thereof. BACKGROUND

[0002] Nuclear power, as a potential low-carbon, clean and economic energy source, has the advantages of high energy efficiency, convenient transportation and environmental protection, and plays an important strategic role in the transformation of China's energy structure. In order to reduce the harm of serious nuclear power accidents, sacrificial concrete is set in the third generation of nuclear power plants. Sacrificial concrete is designed to be eroded or damaged preferentially in a specific environment, thereby protecting the main part of the structure. When a serious nuclear power accident occurs, the core melt drops on the sacrificial concrete, with a mass of 20t-80t, which will cause a huge impact and high-temperature destructive damage to the sacrificial concrete. On the one hand, such impact may cause significant damage to the sacrificial concrete; on the other hand, the core melt may melt through the sacrificial concrete, and then melt the core catcher and the containment bottom plate, causing radioactive material leakage and bringing immeasurable consequences. The requirement of nuclear power plant for sacrificial concrete is that it can effectively change the physical and chemical properties of the core melt and prevent the diffusion of radioactive material to the external environment when the core melt accident occurs.

[0003] The current nuclear sacrificial concrete mainly focuses on improving its high-temperature compressive strength, and there is less research on its blast-resistant performance. It is necessary to further explore the effect of sisal fiber on the inhibition of high-temperature blast of sacrificial concrete, and reveal the reasons for reducing high-temperature blast, in order to meet the multifunctional performance requirements of the material in high-temperature environment. This will further promote the engineering application of sacrificial concrete in extreme environments and provide protection for the safety and durability of the structure in high-temperature scenarios of nuclear power plants. Therefore, it is necessary to provide an improved technical solution to the above-mentioned deficiencies in the prior art. SUMMARY

[0004] The present application aims to provide a blast-resistant and impact-resistant sacrificial concrete and a preparation method thereof, to solve or alleviate the problems existing in the prior art.

[0005] In order to achieve the above-mentioned purpose, the present application provides the following technical solution: A blast-resistant and impact-resistant sacrificial concrete, comprising the following components by weight: cement 600-700 parts, ultra-fine fly ash 250-350 parts, silica fume 100-150 parts, quartz sand 900-1100 parts, barium ferrite 70-120 parts, steel fiber 140-170 parts, sisal fiber 4-20 parts, water 193-213 parts, and water reducing agent 15-20 parts.

[0006] Further, the superfine fly ash is fly ash microbead, the particle size range is 10-100 mu m, the specific surface area is greater than 2000 m 2 / kg, the bulk density is 300-500 kg / m 3 .

[0007] Further, the specific surface area of the silica ash is greater than 1300 m 2 / / kg, the average particle size is 0.1-0.3 mu m, and the proportion of particle size less than 0.1 mu m is greater than 80%.

[0008] Further, the quartz sand is continuously graded, and is divided into a first grade of 0.5-1 mm, a second grade of 1-2 mm and a third grade of 2-4 mm; the mass ratio of the first grade, the second grade and the third grade quartz sand is (1-2):(1-3):(1-2).

[0009] Further, the barium ferrite contains more than 12 wt% of BaO and more than 85 wt% of Fe2O3, and the particle size range of the barium ferrite is 1-50 mu m.

[0010] Further, the steel fiber is copper-plated micro-wire steel fiber; the fiber diameter of the steel fiber is 0.15-0.25 mm, and the fiber length is 10-20 mm; the tensile strength of the steel fiber is greater than 2200 MPa.

[0011] Further, the sisal fiber has a fiber length of 10-15 mm, a fiber diameter of 0.10-0.25 mm, and a tensile strength of 500-650 MPa.

[0012] Further, the components include cement 649.65 parts, superfine fly ash 299 parts, silica ash 120.4 parts, quartz sand 1001.70 parts, barium ferrite 100 parts, steel fiber 157 parts, sisal fiber 4.35 parts, water 203.12 parts, and water reducing agent 16.04 parts.

[0013] The application also provides a preparation method of the foregoing blast-resistant and impact-resistant sacrificial concrete, which comprises the following steps: (1) uniformly stirring cement, fly ash microbead, silica ash and barium ferrite to obtain a mixture M1; (2) adding quartz sand into the mixture M1, and stirring to obtain a mixture M2; (3) mixing a part of water with a water reducing agent, and adding into the mixture M2, and stirring to obtain a mixture M3; (4) rinsing containers with the remaining water, and adding into the mixture M3, and stirring to obtain a mixture M4; (5) adding steel fiber and sisal fiber into the mixture M4, and continuing to stir to obtain the blast-resistant and impact-resistant sacrificial concrete, and then forming and curing the blast-resistant and impact-resistant sacrificial concrete.

[0014] Further, the stirring operation in the steps (1), (2) and (3) is 135-145 revolutions / min for 3-5 minutes; and the stirring operation in the steps (4) and (5) is 285-295 revolutions / min for 4-6 minutes.

[0015] Compared with the closest prior art, the technical scheme of the embodiment of the application has the following beneficial effects: The Fe2O3 in the barium ferrite and the SiO2 in the quartz sand in the sacrificial concrete of the application preferentially react with the active reducing agent Zr and U in the core melt to form ZrO2 and UO2, and no hydrogen is generated, and the raw material water return is less than 5%, thereby reducing the hydrogen production in the interaction process between the core melt and the sacrificial material, and showing obvious sacrificial property; the sisal fiber in the sacrificial concrete of the application can inhibit crack propagation to a certain extent and reduce porosity, and under the action of high temperature, the sisal fiber melts to form voids and channels, and the micro-cracks formed by thermal expansion of the steel fiber, thereby effectively releasing steam in a high temperature environment, and improving the impact resistance and high-temperature blast resistance of the blast-resistant and impact-resistant sacrificial concrete.

[0016] The blast-resistant and impact-resistant sacrificial concrete prepared by the application has excellent working performance, can meet the fluidity requirement of self-compacting concrete, and can greatly improve construction efficiency. The blast-resistant and impact-resistant sacrificial concrete prepared by the application has a compressive strength higher than 120 MPa, and can meet the strength requirement of ultra-high performance concrete, through selection and proportion adjustment of raw materials. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a scanning electron microscope image of the sisal fiber in the sacrificial concrete of the embodiment 1 of the application at 25 DEG C.

[0018] Figure 2 It is a scanning electron microscope image of the sisal fiber in the sacrificial concrete of the embodiment 1 of the application at 200 DEG C.

[0019] Figure 3 It is a scanning electron microscope image of the sisal fiber in the sacrificial concrete of the embodiment 1 of the application at 400 DEG C.

[0020] Figure 4 It is a radial scanning electron microscope image of the sisal fiber in the sacrificial concrete of the embodiment 1 of the application at 400 DEG C.

[0021] Figure 5Scanning electron microscope image of steel fiber in sacrificial concrete of example 1 of the present application at 25℃.

[0022] Figure 6 Scanning electron microscope image of steel fiber in sacrificial concrete of example 1 of the present application at 200℃.

[0023] Figure 7 Scanning electron microscope image of steel fiber in sacrificial concrete of example 1 of the present application at 400℃.

[0024] Figure 8 Scanning electron microscope image of steel fiber in sacrificial concrete of example 1 of the present application at 600℃.

[0025] Figure 9 Scanning electron microscope image of steel fiber in sacrificial concrete of example 1 of the present application at 800℃.

[0026] Figure 10 Scanning electron microscope image of steel fiber in sacrificial concrete of example 1 of the present application at 1000℃. DETAILED DESCRIPTION

[0027] The application discloses an anti-burst and anti-impact sacrificial concrete, which is characterized by comprising the following components in parts by weight: cement 600-700 parts, ultra-fine fly ash 250-350 parts, silica fume 100-150 parts, quartz sand 900-1100 parts, barium ferrite 70-120 parts, steel fiber 140-170 parts, sisal fiber 4-20 parts, water 193-213 parts, and water reducing agent 15-20 parts.

[0028] In the application, the cement, fly ash, silica fume, quartz sand and water reducing agent are conventional components of the concrete. For the nuclear power scene, Fe2O3 in the barium ferrite and SiO2 in the quartz sand preferentially react with active reducing agents Zr and U in the reactor core melt to form ZrO2 and UO2, thus showing obvious sacrificial property. In addition, no hydrogen is generated in the reaction process, thereby reducing the hydrogen production in the interaction process between the reactor core melt and the sacrificial material.

[0029] The steel fiber reinforced concrete is tough and has high ability to resist crack propagation, thus improving the tensile strength, bending strength and impact resistance. In addition, under the action of high temperature, the steel fiber will form micro-cracks in the sacrificial concrete due to thermal expansion.

[0030] The incorporation of sisal fibers improves the impact resistance and high-temperature spalling resistance of the sacrificial concrete. Firstly, sisal fibers can effectively inhibit the propagation of micro-cracks and delay the appearance of large cracks. Secondly, sisal fibers can improve the interface transition zone structure of the sacrificial concrete, making it more dense, thereby reducing the porosity of the matrix and optimizing the pore structure. Thirdly, sisal fibers can bridge cracks and absorb impact energy, prolong the stress action time, and significantly enhance the impact resistance of the specimen. Fourthly, under the action of high temperature, sisal fibers will melt at their melting point, forming voids and channels. This process not only connects the micro-cracks formed by the thermal expansion of steel fibers, but also increases the porosity of the material, thereby effectively releasing the steam in the high-temperature environment and improving the high-temperature spalling resistance of the sacrificial concrete.

[0031] The melting point of sisal fibers is 255-260℃. At high temperatures, sisal fibers first undergo shrinkage deformation, and then completely transform into a porous structure when the temperature exceeds their melting point. This not only increases the porosity of the sacrificial concrete, but also effectively connects the micro-cracks caused by the thermal expansion of steel fibers through the formed channel network. This connected crack network provides a diffusion channel for high-temperature steam, effectively relieving the internal steam pressure accumulation and significantly improving the high-temperature spalling resistance of the material. Steel fibers, with their high thermal stability and reinforcing effect, compensate for the strength loss caused by the increase in porosity, maintaining the basic mechanical properties of the material. Figures 1 to 10 The scanning electron microscope photos of the sacrificial concrete at different temperatures, respectively, can be seen from the figure that the morphological change of sisal fibers is not large at 25℃ and 200℃, when the temperature reaches 400℃, sisal fibers shrink and deform, sisal fibers completely melt to form a channel structure and produce micro-cracks in the radial direction; from Figure 4 The radial direction of sisal fibers at 400℃, it can be seen that sisal fibers completely melt to form a channel structure when the temperature reaches the melting point, which is manifested as a hole morphology. With the continuous increase of temperature (25-1000℃), steel fibers undergo a significant oxidation reaction, and the outer surface of the steel fibers becomes rough and the interface, accompanied by a decrease in diameter. In this process, the bonding strength between steel fibers and the matrix gradually decreases, and this interface degradation directly induces the decline of the macroscopic bearing capacity of the material.

[0032] Further, the ultra-fine fly ash is fly ash beads, the particle size range is 10-100μm, the specific surface area is greater than 2000m 2 / kg, and the bulk density is 300-500kg / m 3 . The specific surface area of the silica fume is greater than 1300m 2 / kg, and the average particle size is 0.1-0.3μm, wherein the proportion of particle size less than 0.1μm is greater than 80%.

[0033] Further, the quartz sand is high-quality fine aggregate, continuous grading, divided into first grade 0.5-1mm, second grade 1-2mm, third grade 2-4mm; the mass ratio of the first grade, second grade, third grade quartz sand is (1-2):(1-3):(1-2), preferably 1:1:1. In the concrete, the quartz sand as the fine aggregate continuous grading can reduce the aggregate void, improve the concrete density, reduce the porosity; make the fresh concrete fluidity better, reduce segregation and bleeding, ensure the construction and workability.

[0034] Further, the barium ferrite contains 12wt% or more BaO and 85wt% or more Fe2O3, and the particle size of the barium ferrite ranges from 1 to 50 microns.

[0035] Further, the steel fiber is copper-plated or uncoated micro-fine steel fiber; the fiber diameter of the steel fiber is 0.15-0.25mm, and the fiber length is 10-20mm; the tensile strength of the steel fiber is greater than 2200MPa. The copper plating on the surface of the micro-fine steel fiber is a conventional process of the manufacturer. The previous test shows that whether the steel fiber is copper-plated or not, it does not affect the reinforcing effect and the sacrificial performance in the sacrificial concrete.

[0036] Further, the sisal fiber has a fiber length of 10-15mm, a fiber diameter of 0.10-0.25mm, and a tensile strength of 500-650MPa.

[0037] Further, the cement is P·O52.5 grade ordinary portland cement; the specific surface area of the P·O52.5 grade ordinary portland cement is greater than 370m 2 / kg, the 28d compressive strength is greater than 60MPa, and the loss on ignition is less than 2%. The water reducing agent is a polycarboxylic acid superplasticizer; the density of the polycarboxylic acid superplasticizer is 1.05-1.15g / mL, the pH value is 6-8, and the water-reducing rate is greater than or equal to 33%; when the polycarboxylic acid superplasticizer is in mass fraction, the solid content is greater than or equal to 40%, and when the polycarboxylic acid superplasticizer is in volume fraction, the air content is 6%-8%. The water is tap water or drinking water, which meets the requirements of the "Concrete Water Standard" (JGJ63-2006). The raw materials used in the present application, including sisal fiber and steel fiber, are directly purchased from the market as industrial raw materials, and all the raw materials maintain their initial physical and chemical states without self-modification treatment.

[0038] A preparation method of an anti-burst and anti-impact sacrificial concrete, comprising the following steps: (1) pouring cement, fly ash microbeads, silica fume and barium ferrite into a mixing container, stirring at 135-145rpm for 3-5min to obtain a mixture M1; (2) Add quartz sand to the mixture M1, stir for 3-5 minutes at 135-145 rpm to obtain a mixture M2; (3) Mix a portion of water with water reducing agent, and add to the mixture M2, stir for 3-5 minutes at 135-145 rpm to obtain a mixture M3; (4) Wash the containers with the remaining water, and add to the mixture M3, stir for 4-6 minutes at 285-295 rpm to obtain a mixture M4; (5) Add steel fibers and sisal fibers to the mixture M4, stir for 4-6 minutes at 285-295 rpm to obtain the blast-resistant and impact-resistant sacrificial concrete, which is then molded and cured.

[0039] The method for preparing the blast-resistant and impact-resistant sacrificial concrete aims to fully mix the raw materials (including sisal fibers, steel fibers and other components) of the sacrificial concrete, and ensure the uniform distribution of the raw materials in the matrix. By optimizing the stirring time and speed, the fiber agglomeration can be effectively avoided, thereby improving the consistency of the mechanical properties of the composite material.

[0040] The application will be described in detail below with reference to the embodiments.

[0041] The raw materials used in the embodiments include: The cement is P·O52.5 grade ordinary portland cement, which has a specific surface area of 380.3 m 2 / kg, a 28d compressive strength of 62.4 MPa, and a loss on ignition of 1.01%.

[0042] The superfine fly ash is fly ash microbeads, which have a specific surface area of 2120 m 2 / kg, a bulk density of 415 kg / m3, and a particle size range of 10-100 μm.

[0043] The silica fume has a specific surface area of 1324 m 2 / kg, an average particle size of 0.12 μm, and a SiO2 mass fraction of 97.49% in the silica fume.

[0044] The quartz sand has a SiO2 content of 96.47%, a particle size range of 0.5-1 mm, 1-2 mm and 2-4 mm, and is used according to a mass ratio of 1:1:1.

[0045] The barium ferrite has a BaO content of 12.5% and a Fe2O3 content of 85.82%, and a particle size range of 1-50 μm, and is purchased from Guangzhou Province Meizhou Magnetic Material Co., Ltd.

[0046] The steel fiber is copper-plated micro-wire steel fiber, with a tensile strength of 2500 MPa, a fiber diameter of 0.2 mm, and a fiber length of 13 mm. The steel fiber is purchased from Shanghai Zhenqiang Fiber Co., Ltd.

[0047] The tensile strength of the sisal fiber is 530-630 MPa, the fiber diameter ranges from 0.14-0.20 mm, and the fiber length is 13 mm. The sisal fiber is purchased from the Dongfang Sisal Group Co., Ltd.

[0048] The water-reducing agent is a polycarboxylic acid high-efficiency water-reducing agent, with a density of 1.1 g / mL, a solid content of 41.2%, a pH value of 6.8, a water-reducing rate of 33.9%, and an air content of 6.5%. The water-reducing agent is a polycarboxylic acid polymer compound, produced by Jiangsu Subote New Material Co., Ltd., and the model is PCA-I.

[0049] The water is tap water or drinking water, which meets the requirements of the "Standard for Water for Concrete" (JGJ63-2006).

[0050] Example 1 An anti-burst and anti-impact sacrificial concrete, by weight parts, comprises the following components: cement 649.65 parts, ultra-fine fly ash 299 parts, silica fume 120.4 parts, quartz sand 1001.70 parts, barium ferrite 100 parts, steel fiber 157 parts, sisal fiber 4.35 parts, water 203.12 parts, water-reducing agent 16.04 parts.

[0051] The preparation method of the above-mentioned anti-burst and anti-impact sacrificial concrete comprises the following steps: (1) The cement, fly ash microbeads, silica fume, and barium ferrite are poured into a mixing container, and after stirring at 140 rpm for 4 min, a mixture M1 is obtained; (2) The quartz sand is added to the above-mentioned mixture M1, and after stirring at 140 rpm for 3 min, a mixture M2 is obtained; (3) About three-quarters of the water is mixed with the water-reducing agent, and added to the above-mentioned mixture M2, and after stirring at 140 rpm for 3 min, a mixture M3 is obtained; (4) After rinsing the containers with the remaining water, the water is added to the above-mentioned mixture M3, and after stirring at 290 rpm for 5 min, a mixture M4 is obtained; (5) The steel fiber and sisal fiber are added to the above-mentioned mixture M4, and after stirring at 290 rpm for 5 min, an anti-burst and anti-impact sacrificial concrete is obtained, and the anti-burst and anti-impact sacrificial concrete is molded and cured.

[0052] Example 2 The difference between this embodiment 2 and embodiment 1 is the amount of quartz sand and sisal fiber in the anti-blast and anti-impact sacrificial concrete raw materials. The anti-blast and anti-impact sacrificial concrete is prepared by the method of embodiment 1.

[0053] An anti-blast and anti-impact sacrificial concrete comprises the following components by weight fraction: Cement 649.65 parts, ultra-fine fly ash 299 parts, silica fume 120.4 parts, quartz sand 993.75 parts, barium ferrite 100 parts, steel fiber 157 parts, sisal fiber 8.70 parts, water 203.12 parts, water reducing agent 16.04 parts.

[0054] Embodiment 3 The difference between this embodiment 3 and embodiment 1 is the amount of quartz sand and sisal fiber in the anti-blast and anti-impact sacrificial concrete raw materials. The anti-blast and anti-impact sacrificial concrete is prepared by the method of embodiment 1.

[0055] An anti-blast and anti-impact sacrificial concrete comprises the following components by weight fraction: Cement 649.65 parts, ultra-fine fly ash 299 parts, silica fume 120.4 parts, quartz sand 985.80 parts, barium ferrite 100 parts, steel fiber 157 parts, sisal fiber 13.05 parts, water 203.12 parts, water reducing agent 16.04 parts.

[0056] Comparative example 1 The difference between this comparative example 1 and embodiment 1 is the amount of quartz sand in the sacrificial concrete raw materials, and does not contain sisal fiber. The amount of quartz sand in this comparative example 1 is the same as that in embodiment 3. The sacrificial concrete is prepared by the method of embodiment 1.

[0057] A sacrificial concrete comprises the following components by weight fraction: Cement 649.65 parts, ultra-fine fly ash 299 parts, silica fume 120.4 parts, quartz sand 985.80 parts, barium ferrite 100 parts, steel fiber 157 parts, water 203.12 parts, water reducing agent 16.04 parts.

[0058] Performance detection: The working performance of the anti-blast and anti-impact sacrificial concrete in the above Examples 1-3 was measured according to the "Cement Mortar Fluidity Determination Method" (GB / T2419-2005), and the measurement index was the spread; the 28-day compressive strength of the anti-blast and anti-impact sacrificial concrete in the above Examples 1-3 was measured according to the "Cement Mortar Strength Test Method (ISO Method)" (GB / T17671-2021); the 28-day impact resistance of the anti-blast and anti-impact sacrificial concrete in the above Examples 1-3 was measured by using a dynamic split Hopkinson pressure bar testing device; and the 28-day high-temperature performance (1000°C) of the anti-blast and anti-impact sacrificial concrete in the above Examples 1-3 was measured by using a high-temperature heating device RX5-65-12 type box resistance furnace. The experimental results of the three examples are shown in Table 1 below.

[0059] Table 1 Performance experimental results of the anti-blast and anti-impact sacrificial concrete obtained in Examples 1-3

[0060] As can be seen from Table 1, the spread of the anti-blast and anti-impact sacrificial concrete in the three examples is between 220-260 mm, all meeting the flowability requirements of self-compacting concrete; the compressive strength of the anti-blast and anti-impact sacrificial concrete in the three examples is greater than 120 MPa, all meeting the strength requirements of ultra-high performance concrete; the impact resistance of the anti-blast and anti-impact sacrificial concrete in the three examples is greater than 220 MPa, all meeting the impact resistance requirements of ultra-high performance concrete; the high-temperature (1000°C) mechanical properties of the anti-blast and anti-impact sacrificial concrete in the three examples are all greater than 30 MPa, and no blast phenomenon occurs, all meeting the anti-high-temperature blast requirements of ultra-high performance concrete; the anti-blast and anti-impact sacrificial concrete in the three examples all contain a high content of SiO2 and Fe2O3, which can react with the core melt, and have a clear sacrificial effect.

[0061] Comparative Example and Comparative Example 1, when there is no sisal fiber in the raw materials of the sacrificial concrete, the impact resistance is less than 220 MPa, the high-temperature (1000°C) mechanical property is less than 30 MPa, and the blast phenomenon occurs, which does not meet the relevant requirements of the sacrificial concrete. Mechanism analysis shows that the addition of sisal fiber can be completely melted under the action of high temperature, forming the following improvement effects: (1) the channel structure formed after the sisal fiber is melted generates a micro-crack network in the radial direction, significantly improving the porosity of the sacrificial concrete; (2) the above channel structure can provide an escape channel for the water vapor generated inside the sacrificial concrete in a high-temperature environment, thereby effectively inhibiting the high-temperature blast behavior of the concrete.

[0062] In summary, the application has simple preparation process, and can be produced by using conventional forced concrete mixer; the blast-resistant and impact-resistant sacrificial concrete prepared by the application has excellent working performance, can achieve the fluidity requirement of self-compacting concrete, and can greatly improve construction efficiency; the blast-resistant and impact-resistant sacrificial concrete prepared by the application has compressive strength higher than 120 MPa, and can meet the strength requirement of ultra-high performance concrete; the blast-resistant and impact-resistant sacrificial concrete prepared by the application has impact-resistant performance higher than 220 MPa, and can meet the impact-resistant performance requirement of ultra-high performance concrete; the blast-resistant and impact-resistant sacrificial concrete prepared by the application has sisal fiber melting under high temperature environment, forms pores and channels, releases high-temperature steam, and can meet the blast-resistant performance requirement of ultra-high performance concrete; the blast-resistant and impact-resistant sacrificial concrete prepared by the application contains high content of SiO2 and Fe2O3, and reacts with active reducing agent Zr and U in the core melt, thereby reducing hydrogen production, and can meet the sacrificial performance requirement of ultra-high performance concrete. The blast-resistant and impact-resistant sacrificial concrete prepared by the application can not only be used in the core catcher of the third-generation nuclear power plant, but also can be used in the core catcher of the fourth-generation nuclear power plant in the future, and has significant engineering application value.

[0063] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A sacrificial concrete that is resistant to bursting and impact, characterized by: The invention comprises the following components in parts by weight: 600-700 parts of cement, 250-350 parts of ultrafine fly ash, 100-150 parts of silica fume, 900-1100 parts of quartz sand, 70-120 parts of barium ferrite, 140-170 parts of steel fiber, 4-20 parts of sisal fiber, 193-213 parts of water and 15-20 parts of water reducing agent.

2. The anti-burst and anti-impact sacrificial concrete according to claim 1, characterized in that: The ultrafine fly ash is fly ash microbeads with a particle size range of 10-100 μm and a specific surface area greater than 2000 m 2 / kg, bulk density is 300-500kg / m 3 .

3. The explosion-resistant and impact-resistant sacrificial concrete according to claim 1, characterized in that: The specific surface area of ​​the silica fume is greater than 1300m 2 / kg, with an average particle size of 0.1-0.3μm, of which the proportion of particles smaller than 0.1μm is greater than 80%.

4. The explosion-resistant and impact-resistant sacrificial concrete according to claim 1, characterized in that: The quartz sand is continuously graded and is divided into a first grade of 0.5-1 mm, a second grade of 1-2 mm, and a third grade of 2-4 mm; the mass ratio of the first grade, the second grade, and the third grade quartz sand is (1-2):(1-3):(1-2).

5. The explosion-resistant and impact-resistant sacrificial concrete according to claim 1, characterized in that: The barium ferrite contains more than 12 wt % of BaO and more than 85 wt % of Fe2O3, and the particle size of the barium ferrite is in the range of 1-50 μm.

6. The explosion-resistant and impact-resistant sacrificial concrete according to claim 1, characterized in that: The steel fiber is a microfilament steel fiber; the fiber diameter of the steel fiber is 0.15-0.25 mm, the fiber length is 10-20 mm; and the tensile strength of the steel fiber is greater than 2200 MPa.

7. The explosion-resistant and impact-resistant sacrificial concrete according to claim 1, characterized in that: The sisal fiber has a fiber length of 10-15 mm, a fiber diameter of 0.10-0.25 mm, and a tensile strength of 500-650 MPa.

8. The explosion-resistant and impact-resistant sacrificial concrete according to claim 1, characterized in that: The invention comprises the following components in parts by weight: 649.65 parts of cement, 299 parts of ultrafine fly ash, 120.4 parts of silica fume, 1001.70 parts of quartz sand, 100 parts of barium ferrite, 157 parts of steel fiber, 4.35 parts of sisal fiber, 203.12 parts of water and 16.04 parts of water reducing agent.

9. A method for preparing the explosion-resistant and impact-resistant sacrificial concrete according to any one of claims 1 to 8, characterized in that: The following steps are involved: (1) Cement, fly ash microbeads, silica fume, and barium ferrite are uniformly mixed to obtain a mixture M1; (2) Quartz sand is added to the above mixture M1 and stirred to obtain a mixture M2; (3) A portion of water is mixed with a water reducer, and the mixture is added to the above mixture M2 and stirred to obtain a mixture M3; (4) After rinsing each container with the remaining water, the remaining water is added to the above mixture M3 and stirred to obtain a mixture M4; (5) Steel fiber and sisal fiber are added to the above mixture M4 and the stirring is continued to obtain a sacrificial concrete that is resistant to explosion and impact, and the sacrificial concrete that is resistant to explosion and impact can be formed and cured.

10. The method for preparing the explosion-resistant and impact-resistant sacrificial concrete according to claim 9, characterized in that: The stirring operation in step (1), step (2) and step (3) is 135-145 rpm for 3-5 min; the stirring operation in step (4) and step (5) is 285-295 rpm for 4-6 min.

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