阅读说明：本技术 一种赤铁矿混凝土及其配比设计方法 (Hematite concrete and proportioning design method thereof ) 是由 张有佳 李小军 刘旭晨 王子彦 王冲 陈彦达 于 2021-01-05 设计创作，主要内容包括：本发明涉及混凝土,特别涉及防辐射混凝土,是一种赤铁矿混凝土,其特征是,由重量份比的水泥、水、赤铁矿砂、赤铁矿石和减水剂组成。其赤铁矿混凝土的配比设计方法包括以下步骤：1)计算试配强度；2)确定水与水泥的比；3)确定单位用水量；4)确定骨料用量。密度高,强度大,而且相对于其他防辐射混凝土,防辐射效果更好。(The invention relates to concrete, in particular to radiation-proof concrete, which is hematite concrete and is characterized by comprising cement, water, hematite sand, hematite ore and a water reducing agent in parts by weight. The design method of the proportion of the hematite concrete comprises the following steps: 1) calculating the trial intensity; 2) determining the ratio of water to cement; 3) determining unit water consumption; 4) and determining the using amount of the aggregate. High density and high strength, and has better radiation-proof effect compared with other radiation-proof concrete.)

1. The hematite concrete is characterized by comprising the following materials in parts by weight: 135.45 parts of cement, 354.674-450 parts of water, 980.656-1011.160 parts of hematite sand, 2083.894-2148.716 parts of hematite ore and 0.709-2.25 parts of water reducing agent;

the hematite concrete is hematite concrete with a compressive strength standard value of 40 MPa.

2. A proportioning design method of hematite concrete is characterized by comprising the following steps:

1) calculating trial strength

The trial strength is calculated according to equation (1)

f_cu,0＝f_cu,k+tσ (1)

In the formula: fcu0, concrete adaptive strength, fcuk, designed concrete cube compressive strength standard value, t-probability, taking t as 1.645, sigma as concrete strength standard difference, and taking sigma as 6.5;

2) determining the ratio of water to cement

The ratio of water to cement is calculated according to equation (2)

In the formula: w is the water consumption of the concrete, c is the cement consumption, alpha a is a regression coefficient, 0.55, fce is taken as the actual strength of the cement, fcu0 is the adaptive strength of the concrete, and alpha b is a regression coefficient, and 0.45 is taken as the regression coefficient;

3) determining unit water consumption

Firstly, the slump is 110mm, and the reference water consumption of the barite radiation-proof concrete in unit volume is taken as the value in the table 1

TABLE 1 Standard Water consumption (kg/m) of radiation-proof concrete³)

When the slump is more than 90mm, the water consumption of the radiation-proof concrete is adjusted by taking the water consumption of which the slump is 75-90 mm in the table 1 as a base number and increasing the water consumption by 5kg every time the slump is increased by 20 mm;

② the reference water consumption for mixing the water reducing agent is calculated according to the formula (3)

m_w0＝m_wX (1-Water reducing Rate) (3)

In the formula: mw0 actual water consumption, mw benchmark water consumption;

thirdly, the cement consumption is calculated according to the formula (4)

In the formula: c-cement consumption, mw 0-actual water consumption,-the ratio of water to cement,

fourthly, the dosage of the water reducing agent is calculated according to the formula (5)

The dosage of the water reducing agent is C multiplied by the mixing amount of the water reducing agent (5)

4) Determining the amount of aggregate

Aggregate gross amount see formula (6)

Aggregate total amount-mass of hematite concrete-mass of cement-mass of water (6)

② thin aggregate prescription (7)

Fine aggregate amount-aggregate total amount x sand rate (7)

③ coarse aggregate measuring type (8)

The amount of coarse aggregate is the total amount of aggregate-the amount of fine aggregate (8).

The technical field is as follows:

the invention relates to concrete, in particular to radiation-proof concrete, namely hematite concrete and a proportioning design method thereof.

Background art:

the radiation-proof concrete is mainly used for nuclear industry and devices using radioactive isotopes, such as protective structures of reactors, accelerators, radiochemical devices, customs, hospitals and the like. The main function of the concrete can shield the concrete which is harmful to human bodies such as x rays, gamma rays and the like. It is made up by using cement, water and heavy aggregate, and its apparent density is generally above 3000kg/m 3. The heavier the concrete, or the higher the apparent density of the concrete, the better the protection against x-rays and gamma-rays, and the thickness of the protective structure can be reduced. The radiation-proof structure of the composite material of the radiation-proof concrete and the steel plate is applied in the nuclear power station and the hospital at present, so far, the actual application and literature report of the hematite concrete with the apparent density of more than 3700kg/m3 and the proportioning design method thereof are not seen.

When preparing the radiation-proof concrete, cement with strong cementing power and high hydration water content, such as Portland cement, is preferably used, and heavy cement such as strontium silicate is preferably used. When high-alumina cement is adopted for construction, cooling measures are required. The common heavy aggregate is mainly barite (BaSO)₄) Limonite (2 Fe)₂O₃.3H₂O), magnetite (Fe)₃O₄) Hematite (Fe)₂O₃) And the like. In addition, boron, boride, lithium salt and the like are doped, so that the protective performance of the concrete can be effectively improved.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: overcomes the defects of the prior art and provides hematite concrete and a proportioning design method thereof.

1 one of the technical schemes adopted by the invention is as follows: the hematite concrete is characterized by comprising the following materials in parts by weight: 135.45 parts of cement, 354.674-450 parts of water, 980.656-1011.160 parts of hematite sand, 2083.894-2148.716 parts of hematite ore and 0.709-2.25 parts of water reducing agent.

The hematite concrete is hematite concrete with a compressive strength standard value of 40 MPa.

The second technical scheme adopted by the invention is as follows: a proportioning design method of hematite concrete is characterized by comprising the following steps:

1) calculating trial strength

The trial strength is calculated according to equation (1)

f_cu,0＝f_cu,k+tσ (1)

In the formula: fcu0, concrete adaptive strength, fcuk, designed concrete cube compressive strength standard value, t-probability, taking t as 1.645, sigma as concrete strength standard difference, and taking sigma as 6.5;

2) determining the ratio of water to cement

The ratio of water to cement is calculated according to equation (2)

In the formula: w is the water consumption of concrete, c is the cement consumption, alpha a is a regression coefficient, 0.55, fce are taken

Taking the actual strength of the cement, fcu0, the adaptive strength of the concrete, and alpha b as a regression coefficient, and taking 0.45;

3) determining unit water consumption

Firstly, the slump is 110mm, and the reference water consumption of the radiation-proof concrete in unit volume is taken as the value in the table 1

TABLE 1 Standard Water consumption (kg/m) of radiation-proof concrete³)

When the slump is more than 90mm, the water consumption of the radiation-proof concrete is adjusted by taking the water consumption of which the slump in the table is 75-90 mm as a base number and increasing the water consumption by 5kg every 20mm increase of the slump;

② the reference water consumption for mixing the water reducing agent is calculated according to the formula (3)

m_w0＝m_wX (1-Water reducing Rate) (3)

In the formula: mw0 actual water consumption, mw benchmark water consumption;

thirdly, the cement consumption is calculated according to the formula (4)

In the formula: c-cement consumption, mw 0-actual water consumption,-the ratio of water to cement,

fourthly, the dosage of the water reducing agent is calculated according to the formula (5)

The dosage of the water reducing agent is C multiplied by the mixing amount of the water reducing agent (5)

4) Determining the amount of aggregate

Aggregate gross amount see formula (6)

Aggregate total amount-mass of C40 hematite concrete-mass of cement-mass of water (6)

② thin aggregate prescription (7)

Fine aggregate amount-aggregate total amount x sand rate (7)

③ coarse aggregate measuring type (8)

Coarse aggregate amount-fine aggregate amount (8)

The invention has the beneficial effects that: high density and high strength, and has better radiation-proof effect compared with other radiation-proof concrete.

Detailed Description

The present invention will be further described with reference to the following examples.

Embodiment 1, the design method of the ratio of the hematite concrete of this embodiment includes the following steps:

1) calculating trial strength

The trial strength is calculated according to equation (1)

f_cu,0＝f_cu,k+tσ＝40+1.645×6.5＝50.6925MPa (1)

In the formula: fcu0, concrete adaptive strength, fcuk, designed concrete cube compressive strength standard value, t-probability, taking t as 1.645, sigma as concrete strength standard difference, and taking sigma as 6.5;

2) determining the ratio of water to cement

The ratio of water to cement is calculated according to equation (2)

In the formula: w is the water consumption of concrete, c is the cement consumption, alpha a is a regression coefficient, 0.55, fce are taken

Taking the actual strength of the cement, fcu0, the adaptive strength of the concrete, and alpha b as a regression coefficient, and taking 0.45;

3) determining unit water consumption

Firstly, the slump is 75 mm-90 mm, and the reference water consumption of the radiation-proof concrete in unit volume is taken according to the value in the table 1

TABLE 1 Standard Water consumption (kg/m) of radiation-proof concrete³)

When the slump is more than 90mm, the water consumption of the radiation-proof concrete is adjusted by taking the water consumption of which the slump in the table is 75-90 mm as a base number and increasing the water consumption by 5kg every 20mm increase of the slump;

② the reference water consumption for mixing the water reducing agent is calculated according to the formula (3)

m_w0＝m_w(1-Water-reducing ratio) 215 × (1-37%) -135.45 kg/m³ (3)

In the formula: mw0 actual water consumption, mw benchmark water consumption;

thirdly, the cement consumption is calculated according to the formula (4)

In the formula: c-cement consumption, mw 0-actual water consumption,-the ratio of water to cement,

the dosage of the water reducing agent is calculated according to the formula (5), wherein the dosage of the water reducing agent is C multiplied by the dosage of the water reducing agent is 354.674 multiplied by 0.2-0.5%, and the dosage of the water reducing agent is 0.709-1.773 kg/m³ (5)

4) Determining the amount of aggregate

Aggregate gross amount see formula (6)

Aggregate total amount-mass of hematite concrete-mass of cement-mass of water

＝3650-354.674-135.45＝3159.876kg/m³ (6)

② thin aggregate prescription (7)

The amount of fine aggregate (total aggregate amount) and sand rate (3159.876X 0.32%: 1011.160 kg/m)³ (7)

The sand rate is 32 percent,

③ coarse aggregate measuring type (8)

Coarse aggregate amount-fine aggregate amount

Coarse aggregate amount-fine aggregate amount

＝3159.876-1011.160＝2148.716 kg/m³ (8)

The weight ratio of cement, water, hematite sand, hematite ore and water reducing agent of the hematite concrete obtained by the calculation is shown in a specific formula in a table 2

Table 2 specific formulation of example 1

Example 2, the hematite concrete of this example, the proportioning design method is the same as example 1, except that: in the embodiment, 32% of cement and 400kg of cement are adopted, the weight ratio of the cement, the water, the hematite sand, the hematite ore and the water reducing agent is calculated to obtain the hematite concrete, and the specific formula is shown in Table 3

Table 3 specific formulation of example 2

The hematite concrete of the embodiment has the strength of 54MPa to 71.5MPa and the surface density of 3700.74kg/m³～3780.74kg/m³。

Example 3, the hematite concrete of this example has the same proportioning design method as example 1, except that: in the embodiment, 32% of cement and 450kg of cement are adopted, the weight ratio of the cement, the water, the hematite sand, the hematite ore and the water reducing agent of the obtained hematite concrete is calculated, and the specific formula is shown in Table 4

Table 4 specific formulation of example 3

The hematite concrete of the embodiment has the strength of 63.48-72.41 MPa and the surface density of 3700.74kg/m³～3780.74kg/m³。

The present invention is not limited to the present embodiment, and it is possible for those skilled in the art to easily reproduce and modify the present invention without inventive efforts within the scope of the present invention claimed.