How to determine the addition rate of high-performance AE water-reducing agent

Abstract

To provide a method enabling determination of an addition rate of high-performance AE water reducing-agents enabling production of concrete having desired fluidity.SOLUTION: A determination method of an addition rate of high-performance AE water-reducing agents is provided to determine a first addition rate which is the mass ratio of the high-performance AE water reducing agents to cement in concrete materials, in order to produce the concrete by kneading the concrete materials using cement, fine aggregates, coarse aggregates, high-performance AE water-reducing agents, and water. The determination method comprises: a mortar production step of producing mortar by kneading mortar materials using cement, fine aggregates, high-performance AE water reducing agents, and water; a measurement step of measuring a flow value of the mortar; and a determination step of when the flow value is 275 mm or more and 325 mm or less, determining a first addition rate based on a second addition rate, the mass ratio of the high-performance AE water reducing agents to the cement in the mortar materials.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for determining the dosage rate of a high-range water-reducing agent for concrete and mortar. [Background technology]

[0002] At concrete manufacturing sites, tests to evaluate the fluidity of the produced concrete (for example, the slump flow test specified in JIS A 1150:2020) are conducted before shipping.

[0003] Incidentally, it is known that the fluidity of concrete can be adjusted by the mass ratio of the high-range air-entraining water-reducing agent to the cement in the concrete material to be mixed (addition rate of the high-range air-entraining water-reducing agent).

[0004] However, as described in Non-Patent Document 1 below, the fluidity of concrete is significantly affected by factors such as the composition of the concrete materials to be mixed and the concrete manufacturing environment. For this reason, even if concrete is manufactured at a concrete manufacturing site using a previously properly set addition rate of high-range air-entraining water-reducing agent, the fluidity of this concrete may not meet the quality standard. In this case, the concrete cannot be shipped and must be discarded, resulting in a problem of wasting the money and time required to manufacture this concrete. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Kazuo Yamada, Hiroshi Ozu, Mayumi Yano, "Improvement of compatibility with cement by optimizing polycarboxylic acid-based high-range water-reducing agent," Proceedings of the Japan Concrete Institute, Vol. 24, No. 1, 2002, pp. 909-914 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide a method for determining the amount of a high-range water-reducing agent to be added that will produce concrete with a desired fluidity before actually producing concrete and conducting a slump flow test.Another object of the present invention is to provide a method for determining the amount of a high-range water-reducing agent to be added that will produce mortar with a desired fluidity. [Means for solving the problem]

[0007] A first aspect of the present invention is a method for determining a first addition rate, which is the mass ratio of the high-range air-entraining water-reducing agent to the cement in a concrete material, in order to produce concrete by mixing the concrete material using cement, fine aggregate, coarse aggregate, a high-range air-entraining water-reducing agent, and water. In this method, The cement includes cement clinker powder and gypsum powder, The γ value of the cement is 1.50 or more and 7.00 or less, Here, the γ value of the cement is the Cl-F content (mg) per 1 kg of the cement as X (mg / kg), the Cr content (mg) per 1 kg of the cement as X (mg / kg), 6+ It is the value of "X×Y÷1000" where the content (mg) is Y (mg / kg), and the Cl-F refers to the fluorine contained in the cement clinker powder. This method is a mortar manufacturing process for manufacturing mortar by kneading a mortar material using the cement, fine aggregate, the high-performance AE water reducing agent, and water; a measuring step of measuring a flow value of the mortar; and a determination step of determining the first addition rate based on a second addition rate, which is the mass ratio of the high-performance AE water-reducing agent to the cement in the mortar material, when the flow value is 275 mm or more and 325 mm or less.

[0008] In the determining step, for example, the first addition rate can be made to coincide with the second addition rate.

[0009] A second aspect of the present invention is a method for producing the concrete based on the first addition rate determined in the determining step of the method according to the first aspect.

[0010] A third aspect of the present invention is a method for determining a second addition rate, which is the mass ratio of the high-range air-entraining water-reducing agent to the cement in a mortar material, in order to produce mortar by kneading a mortar material using cement, fine aggregate, a high-range air-entraining water-reducing agent, and water. In this method, The cement includes cement clinker powder and gypsum powder, The γ value of the cement is 1.50 or more and 7.00 or less, Here, the γ value of the cement is the Cl-F content (mg) per 1 kg of the cement as X (mg / kg), the Cr content (mg) per 1 kg of the cement as X (mg / kg), 6+ It is the value of "X×Y÷1000" where the content (mg) is Y (mg / kg), and the Cl-F refers to the fluorine contained in the cement clinker powder. This method is a concrete manufacturing process for manufacturing concrete by kneading concrete materials using the cement, fine aggregate, coarse aggregate, the high-performance AE water reducing agent, and water; a measuring step of measuring the flow value of the concrete; and a determination step of determining the second addition rate based on a first addition rate, which is the mass ratio of the high-performance AE water-reducing agent to the cement in the concrete material, when the flow value is 55 cm or more and 65 cm or less. [Effects of the Invention]

[0011] According to the first aspect of the present invention, it is possible to determine the addition rate of a high-range air-entraining water-reducing agent that can produce concrete with desired fluidity before actually producing concrete and conducting a slump flow test. According to the second aspect of the present invention, it is possible to produce concrete with desired fluidity. According to the third aspect of the present invention, it is possible to determine the addition rate of a high-range air-entraining water-reducing agent that can produce mortar with desired fluidity. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is an explanatory diagram for explaining a method for determining the addition rate of a high-range air-entraining water-reducing agent according to a first embodiment of the present invention. [Figure 2] FIG. 2 is an explanatory diagram for explaining a method for determining the addition rate of a high-range AE water-reducing agent according to a second embodiment of the present invention. [Figure 3] FIG. 3 is a graph showing the relationship between the γ value of cement and the flow value of mortar. DETAILED DESCRIPTION OF THE INVENTION

[0013] This section describes a method for determining the dosage rate of a high-range air-entraining water-reducing agent according to a first embodiment of the present invention. This method determines a first dosage rate, which is the mass ratio of the high-range air-entraining water-reducing agent to the cement in a concrete material, in order to produce concrete by kneading the concrete material using cement, fine aggregate, coarse aggregate, a high-range air-entraining water-reducing agent, and water. Specifically, this method is intended to achieve a target flow value of the concrete within a range of 60 cm ± 5 cm.

[0014] In this specification, the term "high-range air-entraining water-reducing agent" refers to a chemical admixture defined in "JIS A 6204: 2011." Also, in this specification, the term "flow value of concrete" refers to the slump flow measured in a slump test defined in "JIS A 1101: 2020."

[0015] As shown in FIG. 1, the method according to this embodiment includes a mortar producing step S1, a measuring step S2, and a determining step S3.

[0016] In the mortar production process S1, before the mortar is actually produced, a mortar mix design is carried out to set the flow value of the mortar to be produced to 275 mm or more and 325 mm or less. In this mortar mix design, a second addition rate, which is the mass ratio of the high-range water-reducing agent to the cement in the mortar material to be mixed, is determined. Mortar is then produced by mixing the mortar material using the high-range water-reducing agent, cement, fine aggregate, and water in amounts corresponding to this second addition rate.

[0017] In the mortar production step S1, the cement used is the same as the cement used as a material for the concrete to be actually produced. For example, Portland cement specified in "JIS R 5210:2009" (one example is ordinary Portland cement containing cement clinker powder and gypsum powder) can be used. For example, the fine aggregate used is the same as the fine aggregate used as a material for the concrete to be actually produced. For example, the high-performance air-entraining water-reducing agent used is the same as the high-performance air-entraining water-reducing agent used as a material for the concrete to be actually produced. For example, a polycarboxylic acid-based agent (i.e., one containing a polycarboxylic acid compound as the main component) can be used. For example, distilled water can be used as the water.

[0018] The γ value of the cement used in the mortar manufacturing process S1 is 1.50 or more and 7.00 or less. In this specification, the γ value of the cement is defined as the ratio of the Cl-F content (mg) per 1 kg of cement to the Cr content (mg / kg) per 1 kg of cement. 6+ It is the value of "X × Y ÷ 1000" where Y (mg / kg) is the content (mg). Cli-F refers to the fluorine contained in cement clinker powder.

[0019] The chemical composition of this cement is, for example, as follows: ig.loss: 1.90 mass% or more and 3.10 mass% or less SiO2 content: 19.40 mass% or more and 20.70 mass% or less Al2O3 content: 4.70 mass% or more and 6.00 mass% or less Fe2O3 content: 2.50 mass% or more and 3.40 mass% or less CaO content: 63.40 mass% or more and 64.70 mass% or less MgO content: 0.70 mass% or more and 2.30 mass% or less SO3 content: 1.60 mass% or more and 2.90 mass% or less Na2O content: 0.15% by mass or more and 0.30% by mass or less K2O content: 0.25 mass% or more and 0.50 mass% or less TiO2 content: 0.20 mass% or more and 0.35 mass% or less P2O5 content: 0.08 mass% or more and 0.30 mass% or less MnO content: 0.01% by mass or more and 0.12% by mass or less

[0020] The mineral composition of the cement clinker powder contained in this cement is, for example, as follows: In this specification, the mineral composition refers to that calculated by the Bogue formula. C3S content: 58.0 mass% or more and 68.0 mass% or less C2S content: 6.0% by mass or more and 14.0% by mass or less C3A content: 7.5% by mass or more and 13.0% by mass or less C4AF content: 8.0% by mass or more and 11.0% by mass or less

[0021] In the measurement step S2, the flow value of the mortar produced in the mortar production step S1 is measured. In this specification, the flow value of the mortar is a measured value in a flow test specified in "JIS R 5201:2015."

[0022] In the determination step S3, it is determined whether the flow value of the mortar measured in the measurement step S2 is within the range of 275 mm or more and 325 mm or less, or outside that range. If it is determined that the flow value of this mortar is within the range of 275 mm or more and 325 mm or less, the first addition rate is determined based on the second addition rate (for example, the first addition rate is made to match the second addition rate). On the other hand, if it is determined that the flow value of this mortar is outside the range of 275 mm or more and 325 mm or less, it is determined that the mortar production step S1 and the measurement step S2 will be performed again.

[0023] Next, a method for manufacturing concrete using the method according to this embodiment will be described. In this manufacturing method, the addition rate of the high-range water-reducing agent (the first addition rate) is determined by the method according to this embodiment, and concrete is manufactured by kneading a concrete material using the high-range water-reducing agent in an amount corresponding to this addition rate, cement, fine aggregate, coarse aggregate, and water.

[0024] In this concrete manufacturing method, the cement used is the same as that used in the mortar manufacturing step S1 of this embodiment. The fine aggregate used is, for example, the same fine aggregate as that used in the mortar manufacturing step S1. Any coarse aggregate can be used. The high-range air-entraining water-reducing agent used is the same as that used in the mortar manufacturing step S1. The water used is, for example, tap water with an air-entraining agent added. In this specification, the air-entraining agent is a chemical admixture defined in "JIS A 6204:2011."

[0025] Next, a method for determining the addition rate of a high-range AE water-reducing agent according to a second embodiment of the present invention will be described. Only differences from the method according to the first embodiment will be described, and the method according to this embodiment is the same as the method according to the first embodiment unless otherwise specified.

[0026] The method according to this embodiment determines a second addition ratio, which is the mass ratio of the high-range air-entraining water-reducing agent to the cement in the mortar material, in order to produce mortar by kneading a mortar material using cement, fine aggregate, a high-range air-entraining water-reducing agent, and water. Specifically, this method is intended to set the flow value of the mortar within a target value of 300 mm ± 25 mm.

[0027] As shown in FIG. 2, the method according to this embodiment includes a concrete producing step S11, a measuring step S12, and a determining step S13.

[0028] In the concrete production process S11, before the concrete is actually produced, a concrete mix design is carried out to set the flow value of the concrete to be produced to between 55 cm and 65 cm. In this concrete mix design, a first addition rate, which is the mass ratio of the high-range water-reducing agent to the cement in the concrete material, is determined. Then, concrete is produced by kneading the concrete material using the high-range water-reducing agent, cement, fine aggregate, coarse aggregate, and water in amounts corresponding to this first addition rate.

[0029] In the concrete production step S11, the cement used is the same as the cement used as a material for the mortar to be actually produced. The fine aggregate used is, for example, the same fine aggregate used as a material for this mortar. Any coarse aggregate can be used. The high-performance air-entraining water-reducing agent used is the same as the high-performance air-entraining water-reducing agent used as a material for this mortar. The water used is, for example, tap water with an air-entraining agent added.

[0030] The conditions for the composition of the cement used in the concrete production step S11 (for example, the range of the γ value) are the same as the conditions for the composition of the cement used in the mortar production step S1 shown in FIG.

[0031] In the measurement step S12, the flow value of the concrete produced in the concrete production step S11 is measured.

[0032] In the determination step S13, it is determined whether the flow value of the concrete measured in the measurement step S12 is within the range of 55 cm or more and 65 cm or less, or outside that range. If it is determined that the flow value of this concrete is within the range of 55 cm or more and 65 cm or less, the second doping rate is determined based on the first doping rate (for example, the second doping rate is made to match the first doping rate). On the other hand, if it is determined that the flow value of this concrete is outside the range of 55 cm or more and 65 cm or less, it is determined that the concrete production step S11 and the measurement step S12 will be carried out again.

[0033] Next, a test example will be described to explain the effect (accuracy) of the methods according to the first and second embodiments of the present invention.

[0034] (Test Method) 1. Concrete mix planning In Test Examples 1 to 7 shown in Table 1, concrete was planned to be produced by mixing concrete materials using ordinary Portland cement, first fine aggregate, second fine aggregate, first coarse aggregate, second coarse aggregate, high-range air-entraining water-reducing agent, air-entraining agent, and tap water. Table 2 shows the mix proportions common to the concrete produced in Test Examples 1 to 7.

[0035] [Table 1]

[0036] [Table 2]

[0037] The symbols shown in Table 2 have the following meanings: W / C: Water-cement ratio (%) C: Concrete 1m 3 Mass of ordinary Portland cement contained per unit (kg / m 3 ) W: Concrete 1m 3Mass of tap water contained per unit (kg / m 3 ) S1: Concrete 1m 3 Mass of first fine aggregate contained per unit (kg / m 3 ) S2: Concrete 1m 3 Mass of second fine aggregate contained per unit (kg / m 3 ) G1: Concrete 1m 3 Mass of first coarse aggregate contained per unit (kg / m 3 ) G2: Concrete 1m 3 Mass of second coarse aggregate contained per unit (kg / m 3 )

[0038] Next, the type of ordinary Portland cement to be used for each of Test Examples 1 to 7 was determined. Specifically, it was decided to use ordinary Portland cement of the type (C-1 to C-7) shown outside the parentheses in the "Type of cement used and γ value" section of Table 1 for Test Examples 1 to 7. The γ value of the ordinary Portland cement used in each of Test Examples 1 to 7 is shown in parentheses in this section. Table 3 shows the chemical composition (unit: mass%) of each of C-1 to C-7 and the mineral composition (unit: mass%) of the cement clinker powder contained in each of C-1 to C-7.

[0039] [Table 3]

[0040] Table 4 shows the surface dry density and water absorption of each of the first fine aggregate, the second fine aggregate, the first coarse aggregate and the second coarse aggregate.

[0041] [Table 4]

[0042] Furthermore, based on the type of ordinary Portland cement used in each of Test Examples 1 to 7, the concrete 1 m3 Mass of high-performance AE water-reducing agent contained per unit (kg / m 3 ) and 1m of concrete 3 Mass of AE agent contained per unit (kg / m 3 ) was decided.

[0043] The "High-performance AE water reducing agent content (addition rate)" in Table 1 is "per 1 m of concrete 3 Mass of ordinary Portland cement contained per unit (kg / m 3 )" to "1m of concrete 3 Mass of high-performance AE water-reducing agent contained per unit (kg / m 3 ) (i.e., the mass percentage of the high-range air-entraining water-reducing agent relative to ordinary Portland cement in the concrete material).

[0044] In Test Examples 1 to 7, "Concrete 1 m 3 Mass of ordinary Portland cement contained per unit (kg / m 3 )" to "1m of concrete 3 Mass of AE agent contained per unit (kg / m 3 )" percentages are as follows: Test Examples 1-3, 6, and 7: 0.003% Test Examples 4 and 5: 0.005%

[0045] 2. Concrete production In Test Examples 1 to 7, concrete was produced based on the above-mentioned "1. Concrete Mixing Plan." The concrete production procedure is as follows. All of the following steps were carried out using a mixer. Step 1: Ordinary Portland cement, first fine aggregate, and second fine aggregate were mixed for 15 seconds. Step 2: The mixture obtained in Step 1, tap water, a high-range air-entraining water-reducing agent, and an air-entraining agent were kneaded for 120 seconds. Step 3: The mixture obtained in Step 2, the first coarse aggregate, and the second coarse aggregate were mixed for 90 seconds. Step 4: The kneaded mixture obtained in Step 3 was left to stand for 5 minutes immediately after the completion of Step 3. Step 5: The kneaded material obtained in step 4 was kneaded for 15 seconds immediately after the completion of step 4. Step 6: The mixture (concrete) obtained in Step 5 was collected from the mixer.

[0046] 3. Measurement of concrete flow value and calculation of relative flow area ratio In Test Examples 1 to 7, the flow values ​​of the produced concrete were measured, and the relative flow area ratio was calculated based on these flow values. The relative flow area ratio is an index showing the fluidity of a cement mixture (mortar or concrete) and is expressed by the following formula. Relative flow area ratio = [(flow value - base diameter of slump cone) / (base diameter of slump cone)] squared In the section "Concrete flow value (cm) and relative flow area ratio" in Table 1, the measured results of the concrete flow value (cm) are shown outside the parentheses, and the calculated results of the concrete relative flow area ratio are shown inside the parentheses.

[0047] 4.Mortar mix planning In Test Examples 1 to 7 shown in Table 1, mortars were planned to be produced by mixing the following mortar materials. Mortar materials: Ordinary Portland cement (the same as that used in "2. Concrete Production" above) First fine aggregate and second fine aggregate (the same as those used in "2. Concrete production" above) High-performance AE water-reducing agent (the same as that used in "2. Concrete production" above) Distilled water The first coarse aggregate, the second coarse aggregate and the air-entraining agent used in "2. Production of concrete" above were not used as mortar materials.

[0048] Table 5 shows the common mix proportions for the mortars produced in Test Examples 1 to 7. The symbols shown in Table 5 have the following meanings. C: Mortar 1m 3 Mass of ordinary Portland cement contained per unit (kg / m 3 ) W: Mortar 1m 3 Mass of distilled water contained per unit (kg / m 3 ) S1: Mortar 1m 3 Mass of first fine aggregate contained per unit (kg / m 3 ) S2: Mortar 1m 3 Mass of second fine aggregate contained per unit (kg / m 3 )

[0049] [Table 5]

[0050] Furthermore, in each of Test Examples 1 to 7, 3 Mass of ordinary Portland cement contained per unit (kg / m 3 )" to "Mortar 1m 3 Mass of high-performance AE water-reducing agent contained per unit (kg / m 3 )" percentage is calculated based on the "1. Concrete Mix Plan" above. 3 Mass of ordinary Portland cement contained per unit (kg / m 3 )" to "1m of concrete 3 Mass of high-performance AE water-reducing agent contained per unit (kg / m 3 ) percentage.

[0051] 5. Mortar manufacturing In Test Examples 1 to 7, mortar was produced based on the above-mentioned "4. Mortar Mixing Plan." The mortar was produced according to the following procedure. All of the following steps were carried out using a kneader. Step 1: Ordinary Portland cement, first fine aggregate, and second fine aggregate were mixed at low speed for 30 seconds. Low speed means that the rotation speed of the mixer was 140±5 revolutions per minute and the revolution speed of the mixer was 62±5 revolutions per minute. Step 2: The mixture obtained in Step 1, distilled water, and a high-range air-entraining water-reducing agent were kneaded at the above-mentioned low speed for 60 seconds. Step 3: The operation of the mixer was stopped. In this state, the kneaded material adhering to the kneading bowl and paddles of the mixer was scraped off for 30 seconds so as to be collected in the center of the kneading bowl. Step 4: The mixture obtained in Step 3 was kneaded for 180 seconds at high speed. The high speed means that the rotation speed of the kneader was 285±10 revolutions per minute and the revolution speed of the kneader was 125±10 revolutions per minute. Step 5: The kneaded product (mortar) obtained in Step 4 was recovered from the mixer.

[0052] 6. Measurement of mortar flow value and calculation of relative flow area ratio In Test Examples 1 to 7, the flow value of the mortar was measured, and the relative flow area ratio was calculated based on this flow value. The relative flow area ratio is expressed by the formula in the above section "3. Measurement of concrete flow value and calculation of relative flow area ratio." In the section "Mortar flow value (mm) and relative flow area ratio" in Table 1, the measurement results of the mortar flow value (mm) are shown outside parentheses, and the calculation results of the mortar relative flow area ratio are shown inside parentheses.

[0053] (Test results and discussion) As shown in Table 1, in Test Examples 1, 2, and 4 to 6, the cement γ value was within the range of 1.50 to 7.00, the concrete flow value was within the range of 60 cm ± 5 cm, and the mortar flow value was within the range of 300 mm ± 25 mm. On the other hand, in Test Examples 3 and 7, the cement γ value was outside the range of 1.50 to 7.00, and the mortar flow value was outside the range of 300 mm ± 25 mm. Figure 3 is a graph showing the relationship between the cement γ value and the mortar flow value in Test Examples 1 to 7.

[0054] In other words, if the cement's gamma value is within the range of 1.50 to 7.00, the rate of high-performance AE water-reducing agent to be added to achieve a mortar flow value of 300mm ± 25mm will match the rate of high-performance AE water-reducing agent to be added to achieve a concrete flow value of 60cm ± 5cm.

[0055] Therefore, if the gamma value of the cement is within the range of 1.50 or more and 7.00 or less, and mortar with a flow value of 300 mm ± 25 mm (for example, 280 mm or more and 320 mm or less) can be manufactured, then by matching the addition rate of the high-performance air-entraining water-reducing agent in the production of this mortar with the addition rate of the high-performance air-entraining water-reducing agent in the production of concrete, the flow value of the produced concrete can be made 60 cm ± 5 cm.

[0056] Similarly, if the gamma value of the cement is within the range of 1.50 or more and 7.00 or less, and concrete with a flow value of 60 cm ± 5 cm (for example, 56.0 cm or more and 62.5 cm or less) can be produced, then by matching the addition rate of high-performance air-entraining water-reducing agent in the production of this concrete with the addition rate of high-performance air-entraining water-reducing agent in the production of mortar, the flow value of the produced mortar can be made 300 mm ± 25 mm.

[0057] The relative flow area ratio of mortar with a flow value of 300 mm and concrete with a flow value of 60 cm is 4.00, which means that these mortars and concrete have similar fluidity.

Claims

1. A method for producing concrete by mixing a concrete material using cement, fine aggregate, coarse aggregate, a high-range water-reducing agent, and water, comprising determining a first addition rate, which is a mass ratio of the high-range water-reducing agent to the cement in the concrete material, the method comprising: The cement includes cement clinker powder and gypsum powder, The γ value of the cement is 1.50 or more and 7.00 or less, Here, the γ value of the cement is the Cl-F content (mg) per 1 kg of the cement as X (mg / kg), the Cr content (mg) per 1 kg of the cement as X (mg / kg), 6＋ The value of "X × Y ÷ 1000" is obtained by dividing the content (mg) of fluorine by Y (mg / kg), and Cl-F refers to the fluorine contained in the cement clinker powder. a mortar manufacturing process for manufacturing mortar by kneading a mortar material using the cement, fine aggregate, the high-performance air-entraining water-reducing agent, and water; a measuring step of measuring a flow value of the mortar; and a determining step of determining the first addition rate based on a second addition rate, which is a mass ratio of the high-range air-entraining water-reducing agent to the cement in the mortar material, when the flow value is 275 mm or more and 325 mm or less.

2. 2. The method for determining an addition rate of a high-range air-entraining water-reducing agent according to claim 1, wherein in the determination step, the first addition rate is made to coincide with the second addition rate.

3. 3. A method for manufacturing concrete, comprising the step of manufacturing the concrete based on the first addition rate determined in the determination step of the method for determining an addition rate of a high-range air-entraining water-reducing agent according to claim 1 or 2.

4. A method for producing mortar by kneading a mortar material using cement, fine aggregate, a high-range water-reducing agent, and water, comprising determining a second addition rate, which is a mass ratio of the high-range water-reducing agent to the cement in the mortar material, the method comprising: The cement includes cement clinker powder and gypsum powder, The γ value of the cement is 1.50 or more and 7.00 or less, Here, the γ value of the cement is the Cl-F content (mg) per 1 kg of the cement as X (mg / kg), the Cr content (mg) per 1 kg of the cement as X (mg / kg), 6＋ The value of "X × Y ÷ 1000" is obtained by dividing the content (mg) of fluorine by Y (mg / kg), and Cl-F refers to the fluorine contained in the cement clinker powder. a concrete manufacturing process for manufacturing concrete by kneading concrete materials using the cement, fine aggregate, coarse aggregate, the high-performance air-entraining water-reducing agent, and water; a measuring step of measuring the flow value of the concrete; and a determining step of determining the second addition rate based on a first addition rate, which is the mass ratio of the high-range water-reducing agent to the cement in the concrete material, when the flow value is 55 cm or more and 65 cm or less.

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