CN112723827B - Radiation-proof concrete and preparation method thereof - Google Patents

Abstract

The application relates to the technical field of concrete production and preparation, and particularly discloses a radiation-proof concrete and a preparation method thereof, wherein the radiation-proof concrete comprises the following raw material components in parts by weight: 28-32 parts of cement, 15-17 parts of water, 78-82 parts of recrystallized sand, 122 parts of barite 118-doped sand, 60-120 parts of steel shot, 4-6 parts of fly ash, 8.4-18.6 parts of radiation-proof fiber, 2-4 parts of modified hydrotalcite and 0.33-0.64 part of additive; the preparation method of the radiation-proof concrete comprises the steps of preparing an additive into an aqueous solution, and then stirring and mixing the aqueous solution and the components.

Description

Radiation-proof concrete and preparation method thereof

Technical Field

The application relates to the technical field of concrete production and preparation, in particular to radiation-proof concrete and a preparation method thereof.

Background

Radiation refers to the transmission of energy in the form of electromagnetic waves or the movement of sub-atomic particles such as alpha, beta, gamma particles and neutron particles, with the radiation energy being emitted linearly in all directions from the source. The alpha rays and the beta rays have weak penetrating power, and can be eliminated after being blocked by a common wall body, but the gamma rays and the neutron rays have strong penetrating power and large destructive power, so that the human body is irradiated by the gamma rays and the neutron rays to more easily induce symptoms such as cancer, leukemia, malignant tumor, infertility and the like, and can also be complicated with hereditary teratogenesis. The plants are irradiated by gamma rays and neutron rays, which may cause genetic variation and harm the growth of the plants.

Radiation-proof materials are generally used for building construction at places where radiation source buildings are built in scientific research institutions, hospitals and the like, and the radiation sources are prevented from radiating outwards to cause harm to human bodies or animals and plants. Radiation-proof concrete is generally used for building radiation source buildings, and the radiation-proof concrete mainly prevents alpha, beta, gamma and neutron rays from penetrating through walls to cause injury to human bodies.

At present, the radiation-proof concrete prepared at home and abroad is mainly characterized in that the radiation-proof performance of the concrete is improved by adding heavy metal element admixtures, and heavy metal element-containing ores such as serpentine, barite, limonite and the like are also used in actual production to improve the radiation-proof capability of the concrete. Because of the high penetration of gamma rays and neutron rays, it is usually necessary to thicken the wall to prevent gamma rays and neutron rays from penetrating the wall.

With respect to the related art among the above, the inventors consider that the following drawbacks exist: in the use process of the radiation-proof concrete, the thickness of the wall body is generally required to be increased so as to slow down the speed of radiation rays, the rays are finally blocked and absorbed, the radiation-proof performance is improved, the thickness of the wall body is increased, the building cost is increased, and meanwhile, the tensile performance of the wall body is also influenced.

Disclosure of Invention

In order to reduce the thickness of a concrete wall and simultaneously maintain the radiation protection capability, the application provides radiation protection concrete and a preparation method thereof.

In a first aspect, the application provides a radiation-proof concrete which adopts the following technical scheme:

the radiation-proof concrete comprises the following raw material components in parts by weight: 28-32 parts of cement, 15-17 parts of water, 78-82 parts of recrystallized sand, 122 parts of barite 118-doped sand, 60-120 parts of steel shot, 4-6 parts of fly ash, 8.4-18.6 parts of radiation-proof fiber, 2-4 parts of modified hydrotalcite and 0.33-0.64 part of additive; the modified hydrotalcite is prepared by the following method:

s1: mixing hydrotalcite and nitric acid according to the weight ratio of 1:1.5, heating to 50-70 ℃ for reaction for 2-3 hours, and filtering to obtain pretreated hydrotalcite;

s2: mixing the pretreated hydrotalcite and styrene sulfonic acid according to the weight ratio of 1:2, and carrying out anion replacement reaction under the stirring condition for 0.5-1 hour to obtain styrene sulfonic acid intercalated hydrotalcite reaction liquid;

s3: adding an initiator into the reaction solution to carry out polymerization reaction at the temperature of 50-60 ℃ for 1-3 hours to obtain the modified hydrotalcite.

By adopting the technical scheme, the main components in the barite sand and the barite are barium sulfate, and barium ions have good radiation protection capability; the radiation protection capability of the concrete can be further improved by adding the steel shot, and the density of the concrete is increased; the radiation-proof fiber can improve the radiation-proof capability of concrete and can improve the tensile strength of the concrete; the hydrotalcite has magnesium-aluminum ions and radiation protection performance, polystyrene sulfonic acid is intercalated in the modified hydrotalcite, the polystyrene sulfonic acid contains a large amount of hydrogen, the mass of hydrogen nuclei is equal to that of neutrons, the speed of the neutrons is greatly reduced when the hydrogen nuclei and the neutrons collide with each other, and the neutrons are finally absorbed, so that the radiation protection performance of concrete is further improved, and meanwhile, the hydrotalcite absorbs water between layers, collects a large amount of water molecules, and the water molecules can improve the deceleration and absorption effects on the neutron flow; the radiation-proof performance of the concrete is greatly improved due to the comprehensive effect of a plurality of substances, and the neutron particles can be well decelerated while the thickness of the concrete wall is reduced.

Optionally, the initiator is one of dicumyl peroxide and benzoyl peroxide.

By adopting the technical scheme, the organic peroxide can more effectively promote the polymerization of the polystyrene sulfonic acid.

Optionally, the radiation-proof fiber is prepared by the following method:

s1: stirring and mixing a silane coupling agent and ethanol according to a weight ratio of 1:50 to obtain a mixed solution;

s2: and stirring the lead fiber, the borosilicate glass fiber and the mixed solution to obtain a mixture, and drying the mixture to obtain the radiation-proof fiber, wherein the weight ratio of the silane coupling agent to the borosilicate glass fiber to the lead fiber is 1:10: 10-20.

By adopting the technical scheme, the lead fiber has good radiation-proof performance, the borosilicate glass fiber contains boron trioxide, boron atoms have good radiation-proof effect, and the radiation-proof performance and mechanical property of concrete can be improved by matching the lead fiber and the borosilicate glass fiber; the silane coupling agent is attached to the surfaces of the lead fibers and the borosilicate glass fibers, so that the bonding capacity of the lead fibers and the borosilicate glass fibers and the concrete can be improved, the lead fibers and the borosilicate glass fibers are connected more tightly in the concrete, and the radiation protection capacity and the tensile strength of the concrete are further improved; meanwhile, the silicon-oxygen bond in the silane coupling agent has high thermal stability, the molecular chemical bond is not easy to break at high temperature or under radiation, the change along with the temperature is small, the thermal stability of the concrete can be improved, and the possibility that the wall is cracked due to the fact that neutron rays penetrate into the concrete wall to cause heating of the wall is reduced.

Optionally, the silane coupling agent is one of vinyl silane and methacryloxy silane.

By adopting the technical scheme, the vinyl silane and the methacryloxy silane have good adhesive property, and the adhesive capacity of the radiation-proof fiber and concrete can be effectively improved.

Optionally, the steel shots comprise small steel shots with the grain size of 2-4mm and large steel shots with the grain size of 5-10 mm.

By adopting the technical scheme, the large steel shots and the small steel shots are matched for use, the small steel shots can be filled into gaps between the large steel shots, the contact area between the steel shots and radiation rays is increased, and the radiation protection performance of concrete is improved.

Optionally, the weight ratio of the large steel shots to the small steel shots is 1: 1-3.

Through adopting above-mentioned technical scheme, can further improve the radiation protection performance of concrete.

Optionally, the recrystallized sand is medium sand, and the fineness modulus is 2.6-2.8.

By adopting the technical scheme, the concrete workability of the medium sand is better than that of concrete stirred by fine sand and is not easy to bleed, and the specific surface area of the medium sand is larger than that of coarse sand, so that a better radiation-proof effect can be achieved.

Optionally, the admixture comprises a water reducing agent and an air entraining agent, and the weight ratio of the air entraining agent to the water reducing agent is 1: 10-15.

By adopting the technical scheme, the unit water consumption of the concrete can be reduced by using the water reducing agent, and the workability of the concrete is improved; the use of the air entraining agent can enhance the frost resistance of the radiation-proof concrete.

In a second aspect, the application provides a preparation method of radiation-proof concrete, which adopts the following technical scheme:

the preparation method of the radiation-proof concrete comprises the following steps:

weighing each raw material component, adding an additive into water to prepare an additive solution, adding the rest raw material components into the additive solution, and uniformly stirring to obtain the radiation-proof concrete.

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

1. polystyrene sulfonic acid is intercalated in the modified hydrotalcite added in the radiation-proof concrete, the polystyrene sulfonic acid contains a large amount of hydrogen, the mass of hydrogen nuclei is equal to that of neutrons, the speed of the neutrons is greatly reduced when the hydrogen nuclei and the neutrons collide with each other, the hydrogen nuclei and the neutrons are finally absorbed, the radiation-proof performance of the concrete is improved, meanwhile, hydrotalcite interlamination absorbs water, a large amount of water molecules are gathered, and the water molecules can improve the deceleration effect on the neutron flows;

2. the addition of the silane coupling agent can enable the lead fiber and the borosilicate glass fiber to be connected more tightly in the concrete, further improve the radiation protection capability and the tensile strength of the concrete, and simultaneously, the introduction of the silicon-oxygen bond can increase the thermal stability of the concrete and reduce the possibility that the wall body generates heat and accelerates the aging and chapping of the wall body because neutron rays pass through the concrete wall body.

Detailed Description

The radiation-proof concrete used at present is added with heavy metal to improve the radiation-proof performance of the concrete, and because the penetration force of gamma rays and neutron rays is strong, the thickness of the concrete wall needs to be increased to slow down the speed of particles, so that the particles are conveniently absorbed finally, the tensile strength of the concrete is reduced due to the increase of the thickness of the concrete wall, and cracks are easy to occur to influence the radiation-proof effect of the concrete; the inventor finds that the radiation protection performance of the concrete can be greatly improved by introducing the modified hydrotalcite and the radiation protection fiber into the concrete. The interlayer of the modified hydrotalcite contains a large amount of hydrogen-containing polymers, the quality of the radiation particles is similar to that of hydrogen nuclei, the speed of the particles is greatly reduced after the particles and the hydrogen nuclei elastically collide, and the particles are finally easily absorbed by a concrete layer. The hydrotalcite is a metal compound, metal ions have radiation protection performance, and the radiation protection performance is greatly improved after intercalation modification. The silane coupling agent has good bonding capacity, and can tightly connect the lead fibers, the borosilicate glass fibers and the concrete together to form a radiation-proof fiber mesh, so that the radiation-proof performance of the concrete is further improved, and the tensile strength of the concrete can be further improved. The radiation-proof performance of concrete can be greatly improved by compounding a plurality of substances, and the application is based on the invention.

The present application will be described in further detail with reference to examples.

In the invention, P.042.5R cement purchased from Ziboduoshan cement Co., Ltd is selected; the barite and barite are purchased from Shandong Motor Metal materials Co., Ltd, and the fineness modulus of the barite is 2.6-2.8; steel shots purchased from horsepower steel shot science and technology limited, the steel shots being divided into large steel shots and small steel shots; TY-J25 polycarboxylic acid high performance water reducing agent purchased from Chongqing Tianyao building materials Co; an industrial grade sodium abietate air entraining agent with the content of 98 percent is purchased from Jinchuan Shangqi of Jinan; secondary fly ash obtained from Panjin Lisheng environmental protection products, Inc.; HT3 hydrotalcite from Denton Denmark Chemicals, Inc.

Examples

Preparation example 1

Preparing modified hydrotalcite: mixing 0.8kg of hydrotalcite and 1mol/L of nitric acid according to the weight ratio of 1:1.5, heating to 50 ℃, reacting for 2 hours, and filtering to obtain pretreated hydrotalcite; mixing the pretreated hydrotalcite and styrene sulfonic acid according to the weight ratio of 1:2, and carrying out anion replacement reaction under the stirring condition, wherein the stirring speed is 50rpm/min, and the reaction time is 0.5 hour, so as to obtain styrene sulfonic acid intercalated hydrotalcite reaction liquid; and adding 0.02kg of dicumyl peroxide into the reaction solution for polymerization reaction at the temperature of 50 ℃ for 1 hour to obtain the modified hydrotalcite A.

Preparing radiation-proof fibers: stirring and mixing 0.4kg of methacryloxy silane and ethanol according to the weight ratio of 1:50, wherein the concentration of the ethanol is 75 vol% to obtain a mixed solution; and mixing and stirring 4kg of lead fiber and 4kg of borosilicate glass fiber with the mixed solution to obtain a mixture, and baking the mixture at 60 ℃ for 1 hour to obtain the radiation-proof fiber A.

Preparation example 2

Preparing modified hydrotalcite: mixing 1kg of hydrotalcite and 1mol/L of nitric acid according to the weight ratio of 1:1.5, heating to 60 ℃, reacting for 2 hours, and filtering to obtain pretreated hydrotalcite; mixing the pretreated hydrotalcite and styrene sulfonic acid according to the weight ratio of 1:2, and carrying out anion replacement reaction under the stirring condition, wherein the stirring speed is 50rpm/min, and the reaction time is 1 hour, so as to obtain styrene sulfonic acid intercalated hydrotalcite reaction liquid; and adding 0.03kg of benzoyl peroxide into the reaction solution for polymerization reaction at the temperature of 55 ℃ for 2 hours to obtain the modified hydrotalcite B.

Preparing radiation-proof fibers: stirring and mixing 0.5kg of vinyl silane and ethanol according to the weight ratio of 1:50, wherein the concentration of the ethanol is 75 vol% to obtain a mixed solution; and mixing and stirring 10kg of lead fiber and 5kg of borosilicate glass fiber with the mixed solution to obtain a mixture, and baking the mixture at 70 ℃ for 1 hour to obtain the radiation-proof fiber B.

Preparation example 3

Preparing modified hydrotalcite: mixing 1.3kg of hydrotalcite and 1mol/L of nitric acid according to the weight ratio of 1:1.5, heating to 70 ℃, reacting for 3 hours, and filtering to obtain pretreated hydrotalcite; mixing the pretreated hydrotalcite and styrene sulfonic acid according to the weight ratio of 1:2, and carrying out anion replacement reaction under the stirring condition, wherein the stirring speed is 50rpm/min, and the reaction time is 1 hour, so as to obtain styrene sulfonic acid intercalated hydrotalcite reaction liquid; and adding 0.04kg of benzoyl peroxide into the reaction solution for polymerization reaction at the temperature of 60 ℃ for 3 hours to obtain the modified hydrotalcite C.

Preparing radiation-proof fibers: stirring and mixing 0.6kg of vinyl silane and ethanol according to the weight ratio of 1:50, wherein the concentration of the ethanol is 75 vol% to obtain a mixed solution; and mixing and stirring 12kg of lead fiber and 6kg of borosilicate glass fiber with the mixed solution to obtain a mixture, and baking the mixture at 65 ℃ for 1 hour to obtain the radiation-proof fiber C.

Example 1

The radiation-proof concrete of the embodiment is prepared from the following raw materials in parts by weight: 28kg of cement, 15kg of water, 78kg of barite, 118kg of barite, 30kg of small steel shots with the particle size of 2mm, 30kg of large steel shots with the particle size of 5mm, 4kg of fly ash, modified hydrotalcite A2kg, 8.4kg of radiation-proof fibers, 0.3kg of polycarboxylic acid high-performance water reducing agent and 0.03kg of sodium abietate air entraining agent.

The preparation method of the radiation-proof concrete comprises the following steps:

weighing the raw material components, adding the polycarboxylic acid high-performance water reducing agent and the sodium abietate air entraining agent into water to prepare an additive solution, adding the rest raw material components into the additive solution, and uniformly stirring to obtain the radiation-proof concrete.

Example 2

The radiation-proof concrete of the embodiment is prepared from the following raw materials in parts by weight: 30Kg of cement, 16Kg of water, 80Kg of barite, 120Kg of barite, 60Kg of small steel shots with the grain diameter of 3mm, 30Kg of large steel shots with the grain diameter of 8mm, 5Kg of fly ash, modified hydrotalcite B3Kg, 15.5kg of radiation-proof fibers, 0.5Kg of polycarboxylic acid high-performance water reducing agent and 0.05Kg of sodium abietate air entraining agent.

The preparation method of the radiation-proof concrete of this example is the same as that of example 1.

Example 3

The radiation-proof concrete of the embodiment is prepared from the following raw materials in parts by weight: 32kg of cement, 17kg of water, 82kg of barite, 122kg of barite, 90kg of small steel shots with the particle size of 4mm, 30kg of large steel shots with the particle size of 10mm, 6kg of fly ash, 4kg of modified hydrotalcite B, 18.6kg of radiation-proof concrete, 0.6kg of polycarboxylic acid high-performance water reducing agent and 0.04kg of sodium abietate air entraining agent.

The preparation method of the radiation-proof concrete of this example is the same as that of example 1.

Comparative example

Comparative example 1

The comparative example 1 is different from example 1 in that the recrystallized sand in the raw material components is replaced with ordinary river sand having a fineness modulus of 2.6 to 2.8.

Comparative example 2

Comparative example 2 differs from example 1 in that the radiation protective fibers are not included in the raw material components.

Comparative example 3

Comparative example 3 is different from example 1 in that the radiation-proof fiber in the raw material components was replaced with a mixed fiber composed of 4kg of a common lead fiber and 4kg of a common borosilicate glass fiber in mass.

Comparative example 4

Comparative example 4 is different from example 1 in that the raw material components do not contain the modified hydrotalcite.

Comparative example 5

Comparative example 5 is different from example 1 in that the modified hydrotalcite in the raw material components was replaced with the hydrotalcite before modification.

The slump and the expansion of the concrete are tested according to the specification of GB/T50080.

The concrete was subjected to radiation protection testing according to GB 18871.

And testing the mechanical property of the concrete according to GB 50080-2002.

And a nuclear radiation detector is adopted to detect gamma rays, and a neutron source is adopted to detect neutron rays.

Table 1 shows linear attenuation coefficients (cm) of the radiation protective concretes of examples 1 to 3 and comparative examples 1 to 5 ^-1 ) And (6) testing results.

TABLE 1 Linear attenuation coefficient (cm) of radiation-proof concrete ^-1 )

Table 2 shows the results of the workability tests of the radiation protective concrete of examples 1 to 3 and comparative examples 1 to 5.

TABLE 2 workability of radiation-proof concrete

As can be seen by combining examples 1 to 3 and comparative examples 1 to 5 with tables 1 and 2, the radiation-proof concrete of example 2 of the present application has a better radiation-proof effect than other examples and comparative examples, while maintaining good workability. As can be seen by combining examples 1 to 3 and comparative examples 1 to 5 with tables 1 and 2, the radiation protection effect and the construction effect of the radiation protection concrete of the examples are also higher than those of the comparative examples.

By combining the example and the comparative example 1 and combining the table 1 and the table 2, it can be seen that the radiation protection performance of the concrete is obviously reduced after the recrystallized sand is changed into the common river sand, which indicates that the recrystallized sand has a good radiation protection effect. By combining the example and the comparative example 2 and combining the tables 1 and 2, it can be seen that the radiation-proof fiber can effectively improve the radiation-proof performance of the concrete, and can greatly improve the mechanical properties of the concrete. It can be seen from the combination of the example and the comparative example 3 and the combination of tables 1 and 2 that the radiation protection performance and the mechanical performance of the concrete can be further enhanced by the lead fibers and the borosilicate glass fibers treated by the silane coupling agent, which is probably because the silane coupling agent has good adhesive capacity and is attached to the surfaces of the lead fibers and the borosilicate glass fibers, so that the lead fibers and the borosilicate glass fibers can be more tightly and firmly connected with the concrete, fiber nets interwoven with the lead fibers and the borosilicate glass fibers are formed in the concrete, and the fiber nets are firmly connected with each other, so that the mechanical performance of the concrete is improved; meanwhile, the fiber mesh can effectively prevent gamma particles and neutron particles from penetrating through a concrete wall, so that the radiation protection performance of concrete is improved; the silicon-oxygen bonds can increase the thermal stability of concrete and reduce the possibility that neutron rays penetrate through a concrete wall to cause heating of the wall and accelerate chapping of the wall. By combining the example and the comparative example 4, the radiation resistance and the workability of the concrete can be greatly improved by adding the modified hydrotalcite. By combining the example and the comparative example 5 and combining the tables 1 and 2, the hydrotalcite can effectively improve the radiation resistance of the concrete after intercalation modification. The hydrotalcite is a magnesium-aluminum compound, magnesium-aluminum ions have radiation resistance, and the radiation resistance is greatly improved after intercalation modification; meanwhile, free water can be absorbed between hydrotalcite layers, the free water can accelerate the absorption of the decelerated particles in the concrete, and meanwhile, the free water in the hydrotalcite can further improve the thermal stability of the concrete and prolong the service time of the radiation-proof concrete wall. The modified hydrotalcite can greatly reduce the speed of ray particles, increase the radiation protection effect of concrete and reduce the thickness of a radiation protection concrete wall.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.

Claims (8)

1. The radiation-proof concrete is characterized by comprising the following raw material components in parts by weight: 28-32 parts of cement, 15-17 parts of water, 78-82 parts of recrystallized sand, 122 parts of barite 118-doped sand, 60-120 parts of steel shot, 4-6 parts of fly ash, 8.4-18.6 parts of radiation-proof fiber, 2-4 parts of modified hydrotalcite and 0.33-0.64 part of additive; the modified hydrotalcite is prepared by the following method:

s1: mixing hydrotalcite and nitric acid according to the weight ratio of 1:1.5, heating to 50-70 ℃ for reaction for 2-3 hours, and filtering to obtain pretreated hydrotalcite;

s2: mixing the pretreated hydrotalcite and styrene sulfonic acid according to the weight ratio of 1:2, and carrying out anion replacement reaction under the stirring condition for 0.5-1 hour to obtain styrene sulfonic acid intercalated hydrotalcite reaction liquid;

s3: adding an initiator into the reaction solution to carry out polymerization reaction at the temperature of 50-60 ℃ for 1-3 hours to obtain modified hydrotalcite;

the radiation-proof fiber is prepared by the following method:

s 1: stirring and mixing a silane coupling agent and ethanol according to a weight ratio of 1:50 to obtain a mixed solution;

s 2: and stirring the lead fiber, the borosilicate glass fiber and the mixed solution to obtain a mixture, and drying the mixture to obtain the radiation-proof fiber, wherein the weight ratio of the silane coupling agent to the borosilicate glass fiber to the lead fiber is 1:10: 10-20.

2. The radiation protective concrete of claim 1, wherein: the initiator is one of dicumyl peroxide and benzoyl peroxide.

3. The radiation protective concrete of claim 1, wherein: the silane coupling agent is one of vinyl silane and methacryloxy silane.

4. The radiation protective concrete according to claim 1 or 2, characterized in that: the steel shots comprise small steel shots with the grain diameter of 2-4mm and large steel shots with the grain diameter of 5-10 mm.

5. The radiation protective concrete of claim 4, wherein: the weight ratio of the large steel shots to the small steel shots is 1: 1-3.

6. The radiation protective concrete according to claim 1 or 2, characterized in that: the recrystallized sand is medium sand, and the fineness modulus is 2.6-2.8.

7. The radiation protective concrete according to claim 1 or 2, characterized in that: the admixture comprises a water reducing agent and an air entraining agent, and the weight ratio of the air entraining agent to the water reducing agent is 1: 10-15.

8. The method for preparing radiation protective concrete according to any one of claims 1 to 7, characterized by comprising the following steps:

weighing each raw material component, adding an additive into water to prepare an additive solution, adding the rest raw material components into the additive solution, and uniformly stirring to obtain the radiation-proof concrete.