JP2006176397A - High-fluidity mortar composition and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-fluidity mortar composition excellent in fluidity, self-filling property, and material separating resistance, as well as excellent in self-leveling property and underwater non-separability. <P>SOLUTION: When the mortar composition is manufactured by blending a binding material containing at least cement and water and fine aggregate with a thickening admixture and a chemical admixture, a water-binder ratio of 30-70% and a unit quantity of water of 350-450 kg/m<SP>3</SP>are applied. The thickening admixture contains an admixture including a first water-soluble low-molecular compound (A) selected from cationic surfactants and a second water-soluble low-molecular compound (B) selected from anionic aromatic compounds in a ratio of 0.75-1.5 wt% to the unit quantity of water. The chemical admixture contains a polyether-based water reducing agent including a carboxy group in a ratio of 0.5-1.5 wt% to the quantity of cement. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a mortar composition having high fluidity and a method for producing the mortar composition. In particular, the mortar composition is excellent in fluidity, self-filling property and material separation resistance, as well as in self-leveling property and inseparability in water. About.

In existing tunnels, it can be seen that after a long time has passed since the start of service, concrete has been observed to be deformed, such as cracks and peeling. When repairing such concrete, generally, a sheet or concrete plate is wound around the outer periphery, and a space between the sheet or concrete plate and the concrete is filled with mortar, etc. A method of integrating the concrete with the concrete is performed.
As the mortar used in the repair method as described above, by increasing the amount of powder or by using a thickener, the fluidity is improved, and the material separation resistance and non-shrinking property are increased. The thing improved to the outstanding characteristic is used (for example, refer patent document 1).
On the other hand, self-leveling mortar having self-flatness is known as a mortar composition used for naturally ensuring the level of the floor of a building. This mortar composition having self-leveling properties is a material that naturally ensures horizontality after placement of the mortar composition by use of an admixture that exhibits high fluidity and its own weight (see, for example, Patent Document 2).
JP 2002-285153 A JP-A-8-40782

By the way, a mortar composition used for the purpose of repairing tunnel lining concrete is required to have excellent fluidity, self-filling property, and material separation resistance, as well as excellent self-leveling property and non-separability in water. ing.
However, the mortar having high fluidity is excellent in fluidity, material separation resistance, and non-shrinkage, but has problems in water inseparability and self-leveling. In addition, the self-leveling mortar has high fluidity and self-leveling properties, but there is a problem in that the performance cannot be exhibited when it is placed in a narrow space.

  The present invention has been made in view of conventional problems, and has a high fluidity mortar composition excellent in fluidity, self-filling property, material separation resistance, self-leveling property, and in-water non-separability, and its An object is to provide a manufacturing method.

The invention according to claim 1 of the present application is a high fluidity mortar composition obtained by adding a thickening admixture and a chemical admixture to a binder containing at least cement, water, and fine aggregate, The water-binding material ratio, which is the ratio of the binder to the binder, is 30 to 70%, the unit water amount is 350 to 450 kg / m ^3, and the first water-soluble low-molecular compound is used as the thickening admixture. (A) and a second water-soluble low molecular weight compound (B), and the compound (A) and the compound (B) are selected from amphoteric surfactants and anions Combination of compound (B) selected from cationic surfactants, or a combination of compound (A) selected from cationic surfactants and compound (B) selected from anionic aromatic compounds, cationic surfactants A compound selected from (A And a combination of a compound selected from a bromine compound (B), and any one of the additives selected from: a carboxyl group-containing polyether-based water reducing agent as the chemical admixture. It is a feature.

Invention of Claim 2 is chosen from the compound (A) chosen from a cationic surfactant and an anionic aromatic compound as said thickening admixture in the high fluid mortar composition of Claim 1. While using the thickening admixture containing the compound (B), the compound (A) and the compound (B) were blended at a ratio of 0.75 to 1.5% by weight, respectively, with respect to the unit water amount. Is.
Invention of Claim 3 adds the said chemical admixture in the ratio of 0.5 to 1.5 weight% with respect to cement in the high fluid mortar composition of Claim 1 or Claim 2. It is a thing.
Invention of Claim 4 is a manufacturing method of the high fluid mortar composition in any one of Claims 1-3, Comprising: The said 2nd water-soluble low thing is used for a binder, water, and a fine aggregate. After the molecular compound (B) and the chemical admixture are added and kneaded, the first water-soluble low molecular compound (A) is added to the kneaded product and kneaded again to obtain the high fluid mortar composition. It is characterized by being manufactured.

According to the present invention, when the mortar composition is produced, the water binder ratio is set to 30 to 70% and the unit water amount is set to 350 to 450 kg / m ³ . A compound comprising a water-soluble low-molecular compound (A) and a second water-soluble low-molecular compound (B), wherein the compound (A) and the compound (B) are selected from amphoteric surfactants A combination of (A) and a compound (B) selected from an anionic surfactant, or a combination of a compound (A) selected from a cationic surfactant and a compound (B) selected from an anionic aromatic compound, A combination of a compound (A) selected from a cationic surfactant and a compound (B) selected from a bromine compound, and an additive selected from the additives selected from Mixing Since a carboxyl group-containing polyether-based water reducing agent was added, a mortar composition having excellent fluidity, self-filling property, and material separation resistance, as well as excellent self-leveling and non-separability in water can be obtained. .
At this time, an additive containing a compound (A) selected from cationic surfactants and a compound (B) selected from anionic aromatic compounds is used as the thickening additive, and the compound (A) is used. And the compound (B) are mixed at a ratio of 0.75 to 1.5% by weight with respect to the unit water amount, respectively, and the carboxyl group-containing polyether water reducing agent is added to the cement in an amount of 0.5 to 0.5%. If it is added at a ratio of 1.5% by weight, each characteristic of the mortar composition can be reliably improved.

  Moreover, when manufacturing a high fluidity mortar composition, after adding the said 2nd water-soluble low molecular weight compound (B) and the said chemical admixture to a binder, water, and a fine aggregate, it knead | mixes after that. If the first water-soluble low molecular weight compound (A) is added to the product and kneaded again to produce a high fluidity mortar composition, the fluidity, self-filling property, and material separation resistance are excellent. A mortar composition excellent in self-leveling properties and inseparability in water can be reliably produced.

Hereinafter, the best mode of the present invention will be described.
The mortar composition according to the best mode of the present invention contains a carboxyl group-containing polyether-based water reducing agent, which is a chemical admixture, in a binder, water, and fine aggregate, which include cement and an expandable material that is an admixture. In addition, as the thickening admixture, a first water-soluble low molecular compound (A) selected from cationic surfactants, and a second water-soluble low molecular compound (B) selected from anionic aromatic compounds, First, a kneaded product was prepared by kneading a cement admixture and the second water-soluble low-molecular compound (B) into a binder, water, and fine aggregate. Thereafter, the first water-soluble low-molecular compound (A) is added to the kneaded material and kneaded again.
The above-mentioned cement is not particularly limited, and Portland cement such as ordinary Portland cement, early-strength Portland cement, moderately hot Portland cement, white Portland cement such as limestone, clay and iron oxide, blast furnace cement, A mixed cement such as fly ash cement or silica cement can be used.
At this time, the water binder ratio (W / B), which is the ratio of water to the binder, is preferably 30 to 70%. If the water binder ratio is less than 30%, the amount of binder is too large, so the viscosity increases and the required fluidity cannot be ensured. Further, if it exceeds 70%, the amount of the binder becomes too small to obtain the required strength, and the quality of the durability is also lowered by bleeding, so the water binder ratio is 30 to 70%. It is preferably 35 to 45%.
Moreover, as unit water quantity, it is preferable to set it as 350-450 kg / m < ³ >. When the unit water amount is less than 350 kg / m ³ , a decrease in fluidity is observed, and when it exceeds 450 kg / m ³ , the possibility of material separation increases and the durability such as shrinkage decreases. For this reason, the unit water amount is preferably 350 to 450 kg / m ³ .
In addition, there is no limitation in particular as a fine aggregate used for the said mortar, Although the coarse aggregate rate generally used is about 2.7, the coarse grain ratio is 2.05-. A fine aggregate having a coarse and fine intermediate particle size of 2.50 may be used.

  As the first water-soluble low molecular weight compound (A) used in the present invention, a quaternary ammonium salt type cationic surfactant is preferable, and an additive mainly composed of an alkyl ammonium salt is particularly preferable. The second water-soluble low molecular weight compound (B) is preferably a sulfonate having an aromatic ring, and particularly preferably an additive having an alkylallyl sulfonate as a main component. Examples of the low-molecular compound (A) and the second water-soluble low-molecular compound (B) include a compound (A) selected from amphoteric surfactants such as amidopropyl betaine dodecanoate and POE (3) dodecyl ether sulfate. Or a combination of a compound (B) selected from the above anionic surfactants or a compound (A) selected from the above cationic surfactants and a compound (B) selected from bromine compounds such as sodium bromide There may be.

By the way, when the first water-soluble low molecular compound (A) and the second water-soluble low molecular compound (B) are mixed in the cement at a certain ratio, the first water-soluble low molecular compound is mixed. The admixture functions as a thickener by electrically arranging (A) and the second water-soluble low molecular weight compound (B) to form a pseudo polymer. Thus, it is important to add the first water-soluble low molecular weight compound (A) after adding the second water-soluble low molecular weight compound (B) first and kneading.
This is because when the first water-soluble low molecular compound (A) and the second water-soluble low molecular compound (B) are added simultaneously, the first water-soluble low molecular compound (A) and the second water-soluble low molecular compound (B) are added. Since a pseudo polymer is formed in an inhomogeneous state with the water-soluble low molecular weight compound (B), a long time of kneading is required to obtain the desired characteristics by forming the pseudo polymer in a homogeneous state. It is to become.
Further, when the first water-soluble low molecular weight compound (A) is added first, bubbles are generated during kneading and the amount of air in the mortar increases, which may cause a decrease in strength, a decrease in specific gravity, or the like. .
When a chemical admixture and the second water-soluble low molecular weight compound (B) are added and kneaded with a mortar mixer or the like to a binder, water, and fine aggregate, the binder and fine aggregate are mixed. And the mixture is mixed with a solution in which the second water-soluble low-molecular compound (B) and the chemical admixture are dissolved in water, and the materials are uniformly kneaded. can do.
In addition, when kneading using a hand mixer, the stirring performance is lowered when a solution is put into the powder and kneaded. Therefore, the second water-soluble low molecular weight compound (B) and the chemical admixture are added to water. It is preferable to add and knead the mixture in which the binder and the fine aggregate are mixed into a solution in which is dissolved. Thereby, since it can knead | mix without reducing stirring performance, even when a hand mixer is used, a material can be knead | mixed uniformly.

The addition amount of the first water-soluble low molecular compound (A) and the second water-soluble low molecular compound (B) is 0.75 to 1.5% by weight with respect to the unit water amount. It is preferable to mix. When the addition amount of the first water-soluble low molecular compound (A) and the second water-soluble low molecular compound (B) is less than 0.75% by weight, viscosity cannot be obtained and bleeding is caused. Since it increases, the self-filling property, the material separation resistance, and the underwater non-separability are reduced. On the other hand, when the amount exceeds 1.5% by weight, the viscosity increases, and the high flow and self-leveling properties decrease. Therefore, it is preferable to add 0.75 to 1.5% by weight. This makes it possible to obtain a mortar composition that is not only excellent in water inseparability, fluidity, self-filling property, and material separation resistance, but also excellent in water inseparability and self-leveling properties.
Moreover, as a compounding ratio of the said 1st water-soluble low molecular compound (A) and a 2nd water-soluble low molecular compound (B), the range of 2: 5-5: 2 is preferable. As a result of the experiment, it was optimum that the mixing ratio of the first water-soluble low molecular compound (A) and the second water-soluble low molecular compound (B) was 1: 1.

Moreover, as a compounding quantity of the said carboxyl group-containing polyether type water reducing agent, it is preferable to set it as 0.5 to 1.5 weight% with respect to the said binder.
Examples of the concrete chemical admixture for concrete include lignin-based, polycarboxylic acid-based, melamine-based, naphthalene-based, and aminosulfonic acid-based polyether water reducing agents, AE water reducing agents, and high-performance AE water reducing agents. However, in consideration of the compatibility with the thickening admixture, it is preferable to use a carboxyl group-containing polyether water reducing agent having excellent compatibility with the thickening admixture, as in this example. In addition, self-leveling property and high fluidity can be surely exhibited.

Thus, according to the present embodiment, when a mortar composition comprising a chemical admixture and a thickening admixture in a binder composed of cement and an admixture, water and fine aggregate is prepared. And a water-binding material ratio of 30 to 70% and a unit water amount of 350 to 450 kg / m ^3, and a first water-soluble low molecule selected from cationic surfactants as the thickening admixture. The admixture containing the compound (A) and the second water-soluble low-molecular compound (B) selected from anionic aromatic compounds is 0.75 to 1.5% by weight based on the unit water amount, respectively. As a chemical admixture, a carboxyl group-containing polyether-based water reducing agent having excellent compatibility with the thickening admixture is a proportion of 0.5 to 1.5% by weight based on the cement. So that it is fluid, self-filling Is excellent in segregation resistance, it is possible to obtain a self-leveling mortar composition excellent in water non separability.

In the above embodiment, an expandable material is used as the admixture. However, the admixture mixed with the cement is not limited to the expandable material, and other materials such as fly ash, silica fume, and blast furnace slag fine powder are used. These admixtures or mixtures thereof may be used.
Moreover, it is good also considering only a cement as a binder. In this case, the water binder ratio (W / B) becomes the water cement ratio (W / C) as it is.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to an Example at all.
[Example 1]
After adding water to the ordinary Portland cement, which is a binder, and the expanded material, and adjusting the water binder ratio to a predetermined value, a high-performance special dispersant (manufactured by Kao Corporation, carboxyl group-containing polymer) is added. Ether type water reducing agent, trade name "Mighty 4000FA") and high performance special thickener B (trade name "Visco Top 100FA" manufactured by Kao Corporation) mainly composed of alkylallyl sulfonate, After adding silica sand and kneading, a high-performance special thickener A (trade name “Visco Top 100FB” manufactured by Kao Corporation) mainly composed of alkylammonium salt is added to this kneaded product and kneaded again. A mortar composition was prepared. In addition, as a comparative example, conventional high-flow mortar and ordinary mortar are prepared, and for each of the above mortars, material separation resistance, high fluidity, self-leveling property, and inseparability in water are also affected by the operating temperature. Including and comparing.
FIG. 1 is a blending table of a mortar composition according to the present invention (the present invention 1, 2, 3) and conventional high-flow mortar and ordinary mortar used as comparative examples. In consideration of the actual use situation, for the mortar of the present invention, the mixing ratio of the above-mentioned high-performance special thickeners A and B and the addition ratio of the high-performance special dispersant are used. For the high-flow mortar, the high-performance special dispersion is used. Viscosity at each temperature is adjusted by changing the amount of the agent added.
The material separation resistance was evaluated by a bleeding test.
In the bleeding test, a 400 cc mortar is put into a beaker having a capacity of 500 ml, water is sucked up every 30 minutes until bleeding is not recognized immediately after the placing, and the total amount of water accumulated until that time is recorded in units of 1 ml (JIS A 1123- 2003 “Concrete Bleeding Test Method”), the smaller the accumulated water, the smaller the water float (bleeding amount) and the smaller the material separation. FIG. 2 is a table summarizing the amount of bleeding when the temperature of each mortar is 5 ° C., 20 ° C., and 30 ° C. In ordinary mortar, bleeding occurs at each temperature. The mortar and conventional high-flowing mortar showed zero bleeding at any temperature and were confirmed to have excellent material separation resistance.

High fluidity was evaluated based on fluidity.
In this experiment, regarding the fluidity, a vinyl pipe with an inner diameter of 50 mm and a height of 100 mm is placed on an iron plate, the mortar is filled, the pipe is pulled up, and the diameter in two directions at right angles is measured 5 minutes after being pulled up. The value was evaluated by a 5-minute flow test (conforming to JAS 15 M103 “Quality Standards for Self-Leveling Materials”). The larger the 5-minute flow value, the higher the fluidity. FIG. 3 is a graph comparing the flow values (mm) for 5 minutes when the temperature of each mortar is 5 ° C., 20 ° C. and 30 ° C. The mortars of the present invention 1, 2 and 3 are not only conventional mortars but also conventional mortars. Even when compared with the conventional high flow mortar, it showed a high flow value, and it was confirmed that the mortar of the present invention exhibits excellent fluidity.
Self-leveling property was evaluated from fluidity and viscosity.
The viscosity is evaluated from the difference between the 5-minute flow value and the 1-minute flow value in the flow test. The larger the difference is, the higher the viscosity is, and even when the fluidity is high, no material separation occurs. That is, mortar with high fluidity (5 minutes flow value is large) but low viscosity will not flow again once it loses fluidity, and does not have sufficient self-leveling properties, A high and viscous mortar has a slow flow but has a long flow time, so that the flow does not stop and has an excellent self-leveling property.
FIG. 4A is a graph comparing the 5-minute flow value, and FIG. 4B is a graph comparing the difference between the 5-minute flow value and the 1-minute flow value. It is confirmed that the mortar of the present invention has excellent self-leveling properties because it has not only a large flow value for 5 minutes at 5 ° C, 20 ° C, and 30 ° C but also a high flowability, and a large difference in flow values. It was done. In contrast, the conventional high flow mortar has a large 5-minute flow value, but the difference between the 5-minute flow value and the 1-minute flow value is small, and the self-leveling property is inferior to the mortar of the present invention. Recognize.
Moreover, the filling property confirmation test as shown below was conducted, and the mortars were compared for self-filling property and self-leveling property.
Mortar was placed from the right end of a mold having a sheet having a width of 20 mm, a height of 400 mm, and a length of 1700 mm and having a projection having a length of 17 mm on one side of the mold, and the flow gradient and filling condition were measured. In the mortar of the present invention, a flow gradient is generated during the placement, but finally, as shown in FIG. 5 (a), the slope at the top end is approximately horizontal at 1.5% after 8 minutes of placement. It was confirmed that it had good filling properties and self-leveling properties. On the other hand, although the conventional high-flow mortar has a high flow rate, as shown in Fig. 5 (b), the flow finally stopped with a flow gradient of 8.8% after 2 minutes of placement. did. In addition, when a conventional ordinary mortar was placed on the mold, a blockage occurred in the vicinity of the placement portion, and the placement itself was not possible.
Also in this experiment, it was confirmed that the mortar of the present invention is superior in self-leveling property and self-filling property as compared with the conventional high flow mortar.

On the other hand, the underwater inseparability was evaluated by the underwater inseparability and the underwater strength ratio.
The degree of inseparability in water is an index indicating the elution of the alkaline content of the mortar when the mortar is placed in water, and is evaluated by the pH value of the water in which the mortar is introduced. Place 800 ml of water at 20 ° C. into a 1000 ml beaker and gently drop the sample weighed 500 g from the water surface for 20 to 30 seconds. After leaving the drop for 3 minutes, drop the sample using a dropper. While not disturbing, sample 600 ml of water in the beaker and measure its pH (Underwater inseparable concrete design and construction guideline (draft) Appendix 2 Underwater inseparability test method for underwater inseparable concrete ( According to the draft)). According to the Japan Society of Civil Engineers “Underwater inseparable concrete design and construction guideline (draft)”, the pH is 12 or less, and it has sufficient underwater inseparability.
The underwater strength ratio is the ratio between the compressive strength test result of the test specimen prepared in water and the compressive strength test result of the test specimen prepared in the air. Water entrainment is small and excellent in water inseparability. In general, materials having an underwater strength ratio of 70% or more are considered to be materials with a high strength ratio underwater.
FIG. 6 (a) is a graph showing the results of measuring the inseparability of each mortar in water, and the mortars of the present invention 1, 2 and 3 are both below the pH 12, which is the reference value shown by the Japan Society of Civil Engineers. Good results. On the other hand, it can be seen that the conventional high flow mortar has a pH of more than 12 and does not have inseparability in water.
FIG. 6 (b) is a graph comparing the strength ratios in water, and the mortars of the present invention 1, 2, and 3 have all the strength ratios in water at each temperature of 5 ° C., 20 ° C., and 30 ° C. Although it exceeds 70%, the conventional high flow mortar does not reach 70% at 5 ° C.
Thereby, it was confirmed that the mortar of this invention 1,2,3 has the outstanding non-separability in water.

[Example 2]
As shown in the table of FIG. 7, a mortar in which the addition ratio of the high-performance special thickeners A and B, the water cement ratio, the unit water amount, and the addition ratio of the high-performance special dispersant, which are the fluctuation factors of the present invention, are changed Each material was prepared and subjected to various material tests such as a flow test, and the influences on the viscosity, fluidity, material separation resistance, and underwater non-separability due to each variation factor were investigated. In this experiment, only the cement was used as the binder.
Viscosity was evaluated from 20 cm flow time, 1 minute flow value, 5 minute flow value, difference between 1 minute flow value and 5 minute flow value, funnel test, and the like.
The fluidity was evaluated by the difference between the 5-minute flow value, the 1-minute flow value, and the 5-minute flow value.
The material separation resistance was evaluated by visual observation during a flow test, a bleeding test, a placement test, and a split test of the placement test specimen.
About inseparability in water, it evaluated by the pH test when a mortar was dropped in water, and the strength ratio in the air.

表１に示すように、高性能特殊増粘剤の添加率の違いは、粘性、材料分離抵抗性、水中不分離性に対して大きな影響を及ぼしていることがわかる。また、高性能特殊増粘剤の添加率の違いによる各種性能への影響としては、添加率がＷ×０．５０％以下では粘性の低下により材料分離抵抗性、水中不分離性が発揮されず、Ｗ×２．００％以上になると粘性が高くなり、ポンプ圧送負荷が大きくなることや、流動時間が長くなるなど施工性に問題がある。したがって、上記高性能特殊増粘剤の添加率としては、Ｗ×０．７５％〜Ｗ×１．５０％の範囲とすることが好ましい。
（２）水セメント比の違いによる影響
水セメント比の違いによる各種性能の評価結果を以下の表２に示す。
使用したモルタルの配合は、単位水量を４００ｋｇ／ｍ³と一定にして、単位セメント量を１３３４ｋｇ／ｍ³，１０００ｋｇ／ｍ³，８００ｋｇ／ｍ³，６６７ｋｇ／ｍ³，５７２ｋｇ／ｍ³と変化させることにより、水セメント比を３０％，４０％，５０％，６０％，７０％と変化させたもので、高性能特殊分散剤の添加率はＣ×１．０％、高性能特殊増粘剤Ａ，Ｂの添加率はＷ×１．００％とそれぞれ一定とした。

表２に示すように、水セメント比を３０％とすると若干粘性が高くなり、流動性が低下するが、他の特性については影響は少ない。しかし、水セメント比が３０％を下まわる配合では、粘性の増加と流動性の低下により、セルフレベリング性、高流動性、自己充填性が発揮されない。また、水セメント比が７０％を超える配合では強度上の問題が発生するので、水セメント比としては、３０〜７０％の範囲とすることが好ましい。 (1) Influence of the addition rate of high-performance special thickeners The results of evaluation of viscosity, fluidity, material separation resistance, and underwater non-separability due to differences in the addition rates of high-performance special thickeners A and B are as follows. Table 1 shows.
Formulation of mortar used was water-cement ratio of 40%, the unit water amount is 400 kg / m ^3, the unit cement weight is 1000 kg / m ^3, the addition rate of the high-performance special dispersing agent at C × 1.0% high performance The addition ratios of the special thickeners A and B were W × 0.00%, 0.50%, 0.75%, 1.00%, 1.50%, and 2.00%.

As shown in Table 1, it can be seen that the difference in the addition rate of the high-performance special thickener has a great influence on the viscosity, material separation resistance, and in-water non-separability. In addition, as the effect on the various performances due to the difference in the addition rate of the high-performance special thickener, when the addition rate is less than W x 0.50%, the material separation resistance and water inseparability will not be exhibited due to the decrease in viscosity. When W x 2.00% or more, there is a problem in workability such as an increase in viscosity, an increase in pumping load, and a longer flow time. Therefore, the addition rate of the high-performance special thickener is preferably in the range of W × 0.75% to W × 1.50%.
(2) Influence due to difference in water-cement ratio Table 2 below shows the evaluation results of various performances due to the difference in water-cement ratio.
Formulation of mortar used is the unit water content constant at 400 kg / m ^3, to change the unit cement amount and ^{1334kg / m 3, 1000kg / m} 3, 800kg / m 3, 667kg / m 3, 572kg / m 3 By changing the water cement ratio to 30%, 40%, 50%, 60%, 70%, the addition rate of high-performance special dispersant is C x 1.0%, high-performance special thickener The addition rates of A and B were constant at W × 1.00%.

As shown in Table 2, when the water-cement ratio is set to 30%, the viscosity becomes slightly higher and the fluidity is lowered, but the other properties are less affected. However, when the water-cement ratio is less than 30%, the self-leveling property, the high fluidity, and the self-filling property are not exhibited due to an increase in viscosity and a decrease in fluidity. Moreover, since the problem on an intensity | strength will generate | occur | produce when the water cement ratio exceeds 70%, it is preferable to set it as the range of 30 to 70% as a water cement ratio.

表３に示すように、単位水量３５０ｋｇ／ｍ³では流動性が若干低下し、単位水量４５０ｋｇ／ｍ³では材料分離抵抗性が若干低くなるが、他の特性については影響は少ない。
しかし、単位水量が３５０ｋｇ／ｍ³を下まわる配合では、流動性の低下により、セルフレベリング性、高流動性、自己充填性が発揮されない。また、単位水量が４５０ｋｇ／ｍ³を超える配合のものは、材料分離抵抗性の低下による骨材の沈降や、水量が多いことによる収縮量の増大など、耐久性状の問題が発生するので、単位水量としては、３５０ｋｇ／ｍ³〜４５０ｋｇ／ｍ³の範囲とすることが好ましい。
（４）高性能特殊分散剤の添加率による影響
高性能特殊分散剤の添加率の違いによる各種性能の評価結果を以下の表４に示す。使用したモルタルの配合は、水セメント比が４０％、単位水量が４００ｋｇ／ｍ³、単位セメント量が１０００ｋｇ／ｍ³で、高性能特殊分散剤の添加率をＣ×０．５％，１．０％，１．５％とした。また、高性能特殊増粘剤Ａ，Ｂの添加率はＷ×１．００％とした。

表４に示すように、高性能特殊分散剤の添加率による違いは、添加率がＣ×０．５％で流動性が若干小さくなり、Ｃ×１．５％で材料分離抵抗性が若干低くなるが、他の特性については影響は少ない。しかし、高性能特殊分散剤の添加率がＣ×０．５％を下まわる配合では、流動性の低下により、セルフレベリング性、高流動性、自己充填性が発揮されない。また、添加率がＣ×１．５％を超える配合のものは、材料分離抵抗性の低下による骨材の沈降や、ブリーディングの問題が発生するので、高性能特殊分散剤の添加率としては、Ｃ×０．５％〜Ｃ×１．５％の範囲とすることが好ましい。 (3) Influence by the difference in unit water amount The evaluation results of various performances by the difference in unit water amount are shown in Table 3 below. Formulation of mortar used was such that the water-cement ratio is 40%, the unit water content is changed from ^{350kg / m 3, 400kg / m} 3, 450kg / m 3, accordingly, the unit amount of cement 875kg / m ^3, 1000kg / m ^3, which was varied between 1125kg / m ^3, the addition rate of the high-performance special dispersants C × 1.0%, high-performance special thickener a, the addition of B is, W × It was 1.00%.

As shown in Table 3, decrease in fluidity unit water 350 kg / m ³ slightly, but segregation resistance in the unit water amount 450 kg / m ³ is slightly lower, the less impact on other properties.
However, when the unit water content is less than 350 kg / m ³ , self-leveling property, high fluidity, and self-filling property are not exhibited due to the decrease in fluidity. Also, if the unit water content exceeds 450 kg / m ³ , durability problems such as sedimentation of aggregate due to a decrease in material separation resistance and an increase in shrinkage due to a large amount of water occur. the amount of water is preferably in the range of ^{350kg / m 3 ~450kg / m 3} .
(4) Influence of the addition rate of the high-performance special dispersant The evaluation results of various performances due to the difference in the addition rate of the high-performance special dispersant are shown in Table 4 below. The composition of the mortar used is 40% water cement, 400 kg / m ³ unit water amount, 1000 kg / m ³ unit cement amount, C × 0.5%, and 1. It was set to 0% and 1.5%. Moreover, the addition rate of the high-performance special thickeners A and B was W × 1.00%.

As shown in Table 4, the difference depending on the addition rate of the high-performance special dispersant is that the addition rate is C × 0.5%, the fluidity is slightly smaller, and the material separation resistance is slightly lower at C × 1.5%. However, there is little influence on other characteristics. However, when the addition ratio of the high-performance special dispersant is less than C × 0.5%, the self-leveling property, the high fluidity, and the self-filling property are not exhibited due to the decrease in fluidity. In addition, when the addition rate exceeds C × 1.5%, aggregate sedimentation due to a decrease in material separation resistance and bleeding problems occur, so the addition rate of the high-performance special dispersant is as follows: A range of C × 0.5% to C × 1.5% is preferable.

  As described above, according to the present invention, it is possible to obtain a mortar composition that is excellent not only in fluidity, self-filling property, and material separation resistance but also in water inseparability and self-leveling property. Therefore, it is possible to easily provide a backfill material for repairing tunnel lining concrete and a grout material that can be suitably placed even in a narrow space.

It is a figure which shows the mixing | blending of the mortar by this invention used in Example 1, the conventional high fluid mortar used as a comparative example, and a normal mortar. It is a figure which shows the measurement result of the bleeding amount of each mortar used in Example 1. FIG. It is the figure which compared the 5-minute flow value of each mortar used in Example 1. FIG. It is the figure which compared the 5-minute flow value of each mortar used in Example 1, and the difference of a 5-minute flow value and a 1-minute flow value. It is a schematic diagram which shows the result of the filling property confirmation test with the mortar by this invention, and the conventional high fluid mortar. It is the figure which compared the underwater non-separation degree of each mortar used in Example 1, and the underwater strength ratio. It is a figure which shows the mixing | blending of the mortar by this invention used in Example 2, and various material test results.

Claims (4)

A high-flowing mortar composition obtained by adding a kneading agent and a chemical admixture to a binder containing at least cement, water, and fine aggregate, and kneading the water to the binder in a ratio of 30 to 70 % And the unit water amount is 350 to 450 kg / m ^3, and the first water-soluble low-molecular compound (A) and the second water-soluble low-molecular compound (B) are used as the thickening admixture. A combination of a compound (B) selected from an amphoteric surfactant and a compound (B) selected from an amphoteric surfactant, or a cation A combination of a compound (A) selected from a cationic surfactant and a compound (B) selected from an anionic aromatic compound, a compound (A) selected from a cationic surfactant and a compound (B) selected from a bromine compound With Align, using any of the additives of the additives selected from, as the chemical admixture, high-flow mortar composition characterized by using a carboxyl group-containing polyether-based water reducing agent.   As the thickening admixture, a thickening admixture containing a compound (A) selected from cationic surfactants and a compound (B) selected from anionic aromatic compounds is used, and the compound (A) and the above are used. The high flow mortar composition according to claim 1, wherein the compound (B) is blended at a ratio of 0.75 to 1.5% by weight with respect to the unit water amount.   The high flow mortar composition according to claim 1 or 2, wherein the chemical admixture is added at a ratio of 0.5 to 1.5 wt% with respect to the cement. It is a manufacturing method of the high fluid mortar composition in any one of Claims 1-3, Comprising: Said 2nd water-soluble low molecular weight compound (B) and the said chemical mixing to a binder, water, and a fine aggregate. After adding and kneading the agent, the first water-soluble low-molecular compound (A) is added to the kneaded product and kneaded again to produce a high-fluid mortar composition. A method for producing a high fluidity mortar composition.

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