CN112979247A

CN112979247A - Anti-radiation concrete based on barite

Info

Publication number: CN112979247A
Application number: CN202110297715.8A
Authority: CN
Inventors: 张政刚; 李强强
Original assignee: Hangzhou Huajie Commercial Concrete Co ltd
Current assignee: Hangzhou Huajie Commercial Concrete Co ltd
Priority date: 2021-03-19
Filing date: 2021-03-19
Publication date: 2021-06-18

Abstract

The invention discloses a barite-based radiation-proof concrete, and belongs to the technical field of building materials. The radiation-proof concrete comprises the following components in parts by weight: 300 parts of 270-containing cement, 1350-1500 parts of barite, 700-850 parts of barite sand, 350-500 parts of boron ore sand, 60-90 parts of expanding agent, 7-10 parts of water reducing agent, 70-85 parts of admixture and 200 parts of 150-containing water, wherein the apparent density of the barite is 3800-3950 kg/m³The gradation is 8-20 mm; the gradation of the barite sand is 0.13-1.25 mm; the gradation of the boron ore sand is 0.17-2.74 mm; the swelling agent is a UEA swelling agent. The radiation-proof concrete has good mechanical property, thermal stability and radiation-proof property, and can effectively prevent gamma radiation and neutron radiation.

Description

Anti-radiation concrete based on barite

Technical Field

The invention belongs to the technical field of building materials, and particularly relates to a barite-based radiation-proof concrete.

Background

With the development of nuclear industry and the application of radioactive isotopes in the fields of industry, agriculture, medical treatment and electronics, special materials for radiation protection are required in order to prevent nuclear radiation from leaking out and causing damage to human bodies. The existing radiation protection materials are mainly in the following types: (1) metallic shielding material, most commonly lead material. The lead material has excellent shielding performance on both low-energy and high-energy X photons and gamma photons, and is convenient to process and sufficient in yield; (2) the radiation protection glass is prepared by mixing barium carbonate, methacrylic acid and methyl methacrylate in sequence and carrying out free copolymerization on the mixture to prepare the organic barium glass with excellent radiation protection performance, hardness and heat resistance. (3) The metal-base composite protective material is a kind of composite material with light metal as base body and radiation-resisting reinforced phase.

The barite is a nonmetallic mineral with barium sulfate as a main component, and the density of the barite is 4.3-4.5 g/cm³The Mohs hardness is 3-3.5, the chemical property is stable, the paint is insoluble in water and hydrochloric acid, and the paint is nontoxic and magnetic and is easy to absorb X rays and gamma rays.

At present, the application research of preparing radiation-proof materials by using barite abroad is relatively more, for example, the barite concrete prepared by using the barite as coarse and fine aggregate can increase the static density and compactness of the concrete, and has excellent shielding performance on X rays and gamma rays. However, the radiation protection performance of the barite-based concrete still needs to be further improved.

Disclosure of Invention

In order to solve at least one of the above technical problems, the technical solution adopted by the present invention is as follows:

the invention provides a barite-based radiation-proof concrete which comprises the following components in parts by weight: 300 parts of 270-1500 parts of cement, 1350-1500 parts of barite, 700-850 parts of barite sand, 350-500 parts of boron ore sand, 60-90 parts of expanding agent, 7-10 parts of water reducing agent, 70-85 parts of admixture and 200 parts of 150-200 parts of water, wherein the apparent density of the barite is 3800-3950 kg/m3, and the gradation is 8-20 mm; the gradation of the barite sand is 0.13-1.25 mm; the grade composition of the boron ore sand is 0.17-2.74 mm.

Concrete expansive agents are materials that resist shrinkage cracking of concrete, and have been commonly used in underground works and large-volume works. The barite radiation-proof concrete requires compact and uniform concrete without cavities and cracks. And is generally designed underground, and most of the engineering is large-volume concrete engineering. The barite radiation-proof concrete can be selected from a concrete expanding agent, but the efficient concrete expanding agent is preferably selected in consideration of the requirement of the barite radiation-proof concrete on apparent density.

In some implementations of the invention, the expansion agent is a UEA expansion agent. The UEA expanding agent is added to mix to prepare the shrinkage-compensating concrete, a large amount of expansive crystalline hydrate, namely ettringite, is generated after water mixing, the expansion energy generated by the water mixing can be converted into 0.2-0.7 Mpa pre-pressure under the constraint of the adjacent position of the reinforcing steel bar, the pressure can offset the tensile stress generated by concrete shrinkage, the shrinkage cracking of the concrete is prevented or reduced, and the concrete is densified.

In some embodiments of the invention, the barite, barite sand, boronate sand are graded as follows:

in some embodiments of the invention, the cement is selected from one or more of portland cement, pozzolanic portland cement, portland slag cement, high alumina cement, magnesia cement, barium cement, strontium cement, boron-containing cement.

The water reducing agent is an additive capable of reducing water consumption under the condition that concrete slump is basically the same, and is mainly used for improving the performance of concrete mixtures, namely reducing the water consumption, improving the slump and improving the workability. In some embodiments of the invention, the water reducer is a sulfamate-based superplasticizer. In some embodiments of the present invention, the sulfamate-based superplasticizer has a formula of formula (I):

in the invention, the sulfamate-series high-efficiency water reducing agent is prepared by adding sodium aminobenzenesulfonate, phenol and formaldehyde according to the molar ratio of 2:1.23:2.7 at 105 ℃ and pH of 9.3.

In some embodiments of the invention, the admixture is fly ash. In some embodiments of the invention, the fly ash is a class I fly ash.

In the present invention, the radiation is alpha radiation, beta radiation, gamma radiation, X radiation and/or neutron radiation.

The invention has the advantages of

Compared with the prior art, the invention has the following beneficial effects:

the radiation-proof concrete has reasonable raw material selection or preparation and proper proportion, and the apparent density of barite is about 3850kg/m³The apparent density of the obtained concrete even reaches 3600kg/m³Above, far beyond expectations.

The radiation-proof concrete has good mechanical properties, takes 28d compressive strength (MPa), 28d tensile strength (MPa), 28d axial compressive strength (MPa) and elastic modulus (MPa) as examples, is obviously higher than that of each comparative concrete, and has excellent radiation-proof performance.

Generally, the linear expansion coefficient of concrete mixture is increased by doping barite, however, the linear expansion coefficients of the radiation-proof concrete #1, the radiation-proof concrete #2 and the radiation-proof concrete #3 are not higher than that of the comparative concrete #1, and the thermal stability is better.

The linear attenuation coefficient of the radiation-proof concrete of the invention to gamma-ray radiation and neutron radiation is obviously higher than that of each comparative concrete, and is far higher than that of comparative concrete without barite, even obviously higher than that of commercial radiation-proof concrete.

Drawings

Fig. 1 shows the linear attenuation coefficient of gamma radiation for each concrete prepared according to an example of the present invention.

Fig. 2 shows the linear attenuation coefficient of neutron radiation for each concrete prepared according to the example of the present invention.

Detailed Description

Unless otherwise indicated, implied from the context, or customary in the art, all parts and percentages herein are by weight and the testing and characterization methods used are synchronized with the filing date of the present application. Where applicable, the contents of any patent, patent application, or publication referred to in this application are incorporated herein by reference in their entirety and their equivalent family patents are also incorporated by reference, especially as they disclose definitions relating to synthetic techniques, products and process designs, polymers, comonomers, initiators or catalysts, and the like, in the art. To the extent that a definition of a particular term disclosed in the prior art is inconsistent with any definitions provided herein, the definition of the term provided herein controls.

The numerical ranges in this application are approximations, and thus may include values outside of the ranges unless otherwise specified. A numerical range includes all numbers from the lower value to the upper value, in increments of 1 unit, provided that there is a separation of at least 2 units between any lower value and any higher value. For example, if a compositional, physical, or other property (e.g., molecular weight, melt index, etc.) is recited as 100 to 1000, it is intended that all individual values, e.g., 100, 101, 102, etc., and all subranges, e.g., 100 to 166, 155 to 170, 198 to 200, etc., are explicitly recited. For ranges containing a numerical value less than 1 or containing a fraction greater than 1 (e.g., 1.1, 1.5, etc.), then 1 unit is considered appropriate to be 0.0001, 0.001, 0.01, or 0.1. For ranges containing single digit numbers less than 10 (e.g., 1 to 5), 1 unit is typically considered 0.1. These are merely specific examples of what is intended to be expressed and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this application.

When used with respect to chemical compounds, the singular includes all isomeric forms and vice versa (e.g., "hexane" includes all isomers of hexane, individually or collectively) unless expressly specified otherwise. In addition, unless explicitly stated otherwise, the use of the terms "a", "an" or "the" are intended to include the plural forms thereof.

The terms "comprising," "including," "having," and derivatives thereof do not exclude the presence of any other component, step or procedure, and are not intended to exclude the presence of other elements, steps or procedures not expressly disclosed herein. To the extent that any doubt is eliminated, all compositions herein containing, including, or having the term "comprise" may contain any additional additive, adjuvant, or compound, unless expressly stated otherwise. Rather, the term "consisting essentially of … …" excludes any other components, steps or processes from the scope of any of the terms hereinafter recited, insofar as such terms are necessary for performance. The term "consisting of … …" does not include any components, steps or processes not specifically described or listed. Unless explicitly stated otherwise, the term "or" refers to the listed individual members or any combination thereof.

In order to make the technical problems, technical solutions and advantageous effects solved by the present invention more apparent, the present invention is further described in detail below with reference to the following embodiments.

Examples

The following examples are used herein to demonstrate preferred embodiments of the invention. It will be appreciated by those of skill in the art that the techniques disclosed in the examples which follow represent techniques discovered by the inventor to function in the invention, and thus can be considered to constitute preferred modes for its practice. Those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit or scope of the invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs and the disclosures and references cited herein and the materials to which they refer are incorporated by reference.

Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the following claims.

The following examples are conducted in the conventional manner unless otherwise specified. The instruments used in the following examples are, unless otherwise specified, laboratory-standard instruments; the test materials used in the following examples were purchased from a conventional biochemical reagent store unless otherwise specified.

Example 1 barite based radiation protective concrete #1

This example provides a barite-based radiation protective concrete #1 made of 280 parts by weight of cement (Hangzhou Huajie commercial concrete Co., Ltd., ordinary portland cement), 1430 parts by weight of barite (purchased from extended minerals Co., Ltd., Liaoyang county, apparent density of about 3850kg/m³) 820 parts of barite sand (purchased from extended mineral products, Inc. in Liaoyang county), 410 parts of boron ore sand (purchased from Changsha Zhengyao chemical industry, Inc.), 75 parts of UEA expanding agent (purchased from Fujiang alum ore accelerator factory, Anhui), 8.5 parts of water reducing agent, 80 parts of admixture (I-grade fly ash, purchased from Shijiazhuang mineral products, Inc.) and 180 parts of water.

Wherein, the grading table of barite, barite sand and boron ore sand is shown in table 1:

TABLE 1 grading table of barite, barite sand and boron ore sand

The structural formula of the water reducing agent is as follows:

the structural formula is formed by adding sodium aminobenzenesulfonate, phenol and formaldehyde according to the molar ratio of 2:1.23:2.7 at 105 ℃ and the pH value of 9.3.

Example 2 barite based radiation protective concrete #2

This example provides a barite based radiation protective concrete #2 made of 295 parts by weight of cement (Hangzhou)General Portland Cement, product concrete of Huajie, Ltd.), 1390 part by weight of barite (obtained from developed mineral products of Liaoyang county, apparent density of about 3850kg/m³) 750 parts of barite sand (purchased from extended mineral products, ltd. in Liaoyang county), 360 parts of boron ore sand (purchased from Changsha Zhengya chemical industry, ltd.), 80 parts of UEA expanding agent (purchased from Fujiang alum ore accelerator factory, Anhui), 9 parts of water reducing agent, 82 parts of admixture (I-grade fly ash, purchased from Shijiazhuang Tengbang mineral products, ltd.) and 200 parts of water.

The parameters of barite, barite sand, boron ore sand and water reducing agent are the same as those of example 1.

Example 3 barite based radiation protective concrete #3

This example provides a barite-based radiation-protective concrete #3 composed of 275 parts by weight of cement (Hangzhou Huajie commercial concrete Co., Ltd., ordinary portland cement), 1480 parts by weight of barite (purchased from extended minerals Co., Ltd., Liaoyang county, apparent density of about 3850kg/m³) 800 parts of barite sand (purchased from extended mineral products, Inc. in Liaoyang county), 400 parts of boron ore sand (purchased from Changsha Zhengya chemical industry, Inc.), 85 parts of UEA expanding agent (purchased from Fujiang alum ore accelerator factory, Anhui), 8 parts of water reducing agent, 80 parts of admixture (I-grade fly ash, purchased from Shijiazhuang mineral products, Inc.) and 175 parts of water.

Example 4 Properties of barite based radiation protective concrete

In order to verify the mechanical properties and radiation protection properties of the barite based radiation protection concrete #1, radiation protection concrete #2 and radiation protection concrete #3 prepared in examples 1-3, the following comparative concrete was prepared or obtained:

comparative concrete # 1:

the composition was the same as that of the radiation protective concrete #1 of example 1, except that barite and barite sand were replaced with equal and same graded stones and sands.

Comparative concrete # 2:

the composition was the same as that of the radiation protective concrete #1 of example 1 except that the borax sand was replaced with an equal amount of river sand.

Comparative concrete # 3:

the composition was the same as for radiation protective concrete #2 of example 2 except that the UEA expansion agent was replaced with an equal amount of a polymer fiber expansion agent (available from tokyo maple new construction materials ltd).

Comparative concrete # 4:

the composition was the same as that of the radiation-proof concrete #3 of example 3, except that the water reducing agent was replaced with an equal amount of a polycarboxylic acid water reducing agent (available from buhao building materials ltd, shandong) and the amount of water used was increased by 40 parts.

Comparative concrete # 5:

the radiation-proof concrete purchased from Zhongjian West construction Limited company has the apparent density of more than 3000kg/m³。

The slump test method of each concrete mixture is referred to the test method for the performance of ordinary concrete mixtures (GB/T50080).

The apparent density test method of each concrete mixture refers to the test method of the performance of common concrete mixtures (GB/T50080).

The test method of the cubic compressive strength, the splitting tensile strength, the axial compressive strength and the elastic modulus of each concrete refers to the standard of the test method of the mechanical properties of common concrete (GB/T50081).

The method for testing the linear expansion coefficient of each concrete is referred to the Hydraulic concrete test protocol (DL/T5150).

The results are shown in table 2:

TABLE 2 Properties of the concretes

As is clear from Table 2, except comparative concrete #4, the slump constant of each concrete was not so different mainly because the sand ratio and the aggregate ratio of each concrete were not so different. The slump of comparative concrete #4 was relatively high, reaching 79mm, due to the increased water usage.

The apparent density of the barite plays a decisive role in the radiation protection performance of the concrete, and the radiation protection concrete #1, the radiation protection concrete #2 and the radiation protection concrete #3 have the apparent density of about 3850kg/m at the barite due to reasonable raw material selection or preparation and proper proportion³The apparent density of the obtained concrete even reaches 3600kg/m³Above, far beyond expectation, better protection against alpha radiation, beta radiation, gamma radiation, X radiation, even neutron radiation can be achieved.

Radiation protective materials should have good machinability and also should have good structural strength and must not penetrate through gaps, holes, honeycombs and cracks that are likely to transmit radiation. In addition, the building material is also required to have a low modulus of elasticity. The mechanical properties of the radiation-proof concrete #1, the radiation-proof concrete #2 and the radiation-proof concrete #3 are obviously higher than those of each comparative concrete by taking 28d compressive strength (MPa), 28d tensile strength (MPa), 28d axial compressive strength (MPa) and elastic modulus (MPa) as examples, and the radiation-proof concrete has excellent radiation-proof performance.

Finally, in general, the linear expansion coefficient of the concrete mixture is increased due to the incorporation of barite, however, the linear expansion coefficients of the radiation-proof concrete #1, the radiation-proof concrete #2 and the radiation-proof concrete #3 are not higher than that of the comparative concrete #1, and the thermal stability is better.

The inventors further investigated the linear attenuation coefficient of each concrete for gamma radiation and neutron radiation, and the results are shown in table 3, fig. 1 and fig. 2:

TABLE 3 Linear attenuation coefficient (cm) for gamma radiation and neutron radiation for each concrete^-1)

As can be seen from table 3 and fig. 1 and 2, the linear attenuation coefficients of the radiation-proof concrete #1, the radiation-proof concrete #2 and the radiation-proof concrete #3 to gamma radiation and neutron radiation are significantly higher than those of each comparative concrete, and are much higher than that of the comparative concrete #1, and even significantly higher than that of the commercial radiation-proof concrete, i.e., the comparative concrete # 5.

The results also show that the interaction exists among the barite, the boron ore sand, the UEA expanding agent and the water reducing agent, the mechanical property, the thermal stability and the radiation protection property are obviously weakened under the condition that one of the two materials is lacked, and particularly, the properties in all aspects are obviously weakened after the water reducing agent is replaced. The reason is probably that the water reducing agent can better improve the apparent density of concrete, thereby improving the radiation protection capability.

All documents referred to herein are incorporated by reference into this application as if each were individually incorporated by reference. Furthermore, it should be understood that various changes and modifications of the present invention can be made by those skilled in the art after reading the above teachings of the present invention, and these equivalents also fall within the scope of the present invention as defined by the appended claims.

Claims

1. The radiation-proof concrete based on the barite is characterized by comprising the following components in parts by weight: 300 parts of 270-containing cement, 1350-1500 parts of barite, 700-850 parts of barite sand, 350-500 parts of boron ore sand, 60-90 parts of expanding agent, 7-10 parts of water reducing agent, 70-85 parts of admixture and 200 parts of 150-containing water, wherein the apparent density of the barite is 3800-3950 kg/m³The gradation is 8-20 mm; the gradation of the barite sand is 0.13-1.25 mm; the gradation of the boron ore sand is 0.17-2.74 mm; the swelling agent is a UEA swelling agent.

2. The radiation protective concrete of claim 1, wherein the barite, barite sand and boronite sand are graded as follows:

3. the radiation protective concrete of claim 1, wherein the cement is selected from one or more of portland cement, pozzolanic portland cement, portland slag cement, high alumina cement, magnesia cement, barium cement, strontium cement, and boron-containing cement.

4. The radiation protection concrete of claim 1, wherein the water reducing agent is a sulfamate-based superplasticizer.

5. The radiation protection concrete of claim 3, wherein the sulfamate-based superplasticizer has a molecular formula shown in formula (I):

6. the radiation-proof concrete according to claim 4, wherein the sulfamate-based superplasticizer is prepared by adding sodium aminobenzenesulfonate, phenol and formaldehyde in a molar ratio of 2:1.23:2.7 at 105 ℃ and at a pH of 9.3.

7. The radiation protective concrete of claim 1, wherein the admixture is fly ash.

8. The radiation protective concrete of claim 6, wherein the fly ash is class I fly ash.

9. The radiation protective concrete according to claim 1, wherein the radiation is alpha radiation, beta radiation, gamma radiation, X radiation and/or neutron radiation.