JP6907669B2 - Cement mortar / concrete composition and its manufacturing method - Google Patents

Description

The present invention relates to a cement mortar / concrete composition and a method for producing the same. In particular, a cement mortar / concrete composition capable of exhibiting sufficient initial strength even at a low temperature and suppressing the occurrence of initial shrinkage cracks. And its manufacturing method.

Cracks that occur in the early stages of concrete construction are called initial cracks, and there are several types of initial cracks.
For example, subsidence cracks are cracks that occur due to bleeding in concrete, which causes the concrete surface to subside, and the difference in the amount of subsidence. Subsidence cracks can be reduced by suppressing bleeding.

Among the initial cracks, the shrinkage cracks caused by restraining the shrinkage are particularly problematic.
The causes of shrinkage cracks include self-shrinkage of the concrete itself, drying shrinkage, and temperature shrinkage in which heat of hydration is accumulated inside the concrete structure and then dissipated to dissipate heat, which are the causes of shrinkage cracks.
Such shrinkage cracks have a problem that, for example, when the strength is increased, self-shrinkage becomes large and it becomes difficult to suppress the cracks.

Dry shrinkage is related to curing conditions such as humidity and wind, but it can be prevented by measures such as sprinkling a curing agent on the surface of the structure after construction.
The temperature shrinkage is a shrinkage that occurs when the temperature inside the structure rises due to the heat of hydration of cement and falls, and tensile stress is generated due to the restraint of reinforcing bars and the like, and cracks occur.
Self-shrinkage is a shrinkage that combines chemical shrinkage, which is a phase volume change caused by the hydration reaction of cement, and capillary void change, and occurs whenever cement reacts and hardens. In particular, a material such as a hardwood that rapidly hydrates and hardens cement has a large self-shrinkage and is prone to cracking.

Conventionally, as a cement having a fast-hardening property, there is a hard-hardening cement such as a jet cement. As clinker used in these cement, jet cement clinker, C ₄ A ₃ Irwin system to SO ₃ as a main component clinker, alumina cement clinker or the like composed mainly of CA is used.
There is also a method of obtaining _{amorphous C 12} A _{7 by melting a clinker containing C 12} A ₇ as a main component, which is a rapidly hardening component, and then quenching the clinker.

In particular, the conventional jet cement clinker is a clinker containing about 20 to 30% by mass _{of C 11} A ₇ and CaF ₂ as a fast-curing component containing a calcium silicate phase as a main component _{, and C 11} A ₇ CaF ₂ and C ₄ AF. It is formed by forming a melt phase such as. _{Therefore, if the content of C 12} A ₇ which is a rapid-hardening component is set to the above range or more, the melt phase becomes too large and the clinker melts, which makes it very difficult to manufacture, for example, in actual equipment.

Irwin system clinker has been utilized as a rapid hardening cement for clinker since contain Irwin (C 4 _A 3 _{SO 3)} at least 70 mass% with rapid hardening, the characteristics of the rapid-hardening components, in particular, low temperature There is a problem that it is inferior in sharpness.
Further, the alumina cement clinker containing CA as a main component is inferior in rapid hardness to the clinker containing _{C 12} A _{7 as a main component.}

On the other hand, as a cement composition, it has been conventionally practiced to add calcium aluminate and gypsum to Portland cement in order to impart rapid hardness.
However, it has been difficult for a cement composition containing calcium aluminate and a rapid-hardening component of gypsum to obtain sufficient rapid-hardening at a low temperature.

Therefore, Japanese 2014-201462 (Patent Document 1), CaO35~50 _{mass%, Al} 2 O 3 35 to 50 wt% and _SiO 2 7 to 18% by weight of amorphous Shitsudo in chemical composition 70 ^{The content of particles having a brain specific surface area of 4000 to 9000 cm 2} / g and more than 30 μm, which is obtained by crushing an ultrafast-hardening clinker of% or more, is 5% by mass or less, and the content of particles less than 1.0 μm is 5% by mass. A cement composition containing 25 to 200 parts by mass of plaster with respect to 100 parts by mass of an ultrafast-hardening crushed product of% or less is described in Japanese Patent Application Laid-Open No. 2014-196245 (Patent Document 2) as cement, water, and nitrite. Contains calcium, polycarboxylic acid-based water reducing agent and melamine-based water reducing agent, 2 to 5 parts by mass of calcium nitrite, 0.1 to 2.5 parts by mass of polycarboxylic acid-based water reducing agent, and melamine with respect to 100 parts by mass of cement. A cement composition containing 0.1 to 2.5 parts by mass of a water reducing agent is disclosed.

However, in a low temperature environment, it is difficult to promote the hydration reaction to obtain the desired rapid hardness, for example, sufficient strength for 3 hours, and to secure sufficient fluidity of the cement, which is a necessary appropriate amount. This is because the conditions for forming the melt phase and the solid solution state of the rapidly rigid component, that is, the conditions for maximizing the hydration activity do not always match, and it is difficult to design to maximize the hydration activity of the rapidly rigid component. there were.
Furthermore, in a low temperature environment, it was difficult to promote the hydration reaction and effectively suppress the occurrence of initial shrinkage cracks due to self-shrinkage.

Japanese Unexamined Patent Publication No. 2014-201462 Japanese Unexamined Patent Publication No. 2014-196245

An object of the present invention is a cement mortar capable of exhibiting sufficient strength even in a low temperature environment, exhibiting excellent hydration activity and good rapid hardening performance, and suppressing the occurrence of initial shrinkage cracks due to self-shrinkage. The present invention is to provide a concrete composition and a method for producing the same.

In particular, it is an object of the present invention to provide a cement mortar / concrete composition and a method for producing the same, which can suppress initial shrinkage cracks due to self-shrinkage of the mortar / concrete structure even at a low temperature such as 5 ° C.

Cement mortar and concrete composition of claim 1, wherein comprises (1) a cement for rapid hardening additive material containing C ₁₂ A ₇ based mineral phase, and gypsum, and sulfuric acid alkali compound, a calcium salt and lithium carbonate , C ₁₂ A ₇ series minerals 36-55% by mass, alkali sulfate compounds (sodium sulfate equivalent) 0.3-1.7% by mass, lithium carbonate (lithium equivalent) 0.01-1.3% by mass, calcium salt (calcium hydroxide equivalent) containing 1-14 wt%, the mass ratio of the content of gypsum (anhydrite _{equivalent) / C} 12 _{a 7} mineral phase is 0.5 to 1.2, X-ray cement admixture composition crystallite diameter _C 12 _{a 7} mineral phase as measured by diffraction is lattice constant 11.940~11.975Å at 150 to 500 nm, (2) cement, other than (3) lithium carbonate It contains lithium salt and (4) carbonate, and 0.01 to 0.15% by mass of the lithium salt (in terms of lithium), the carbonate, based on the total mass of the cement mixture and cement. characterized in that it comprises (CO ₃ basis) of 0.05 to 0.6 wt%, a cement mortar and concrete compositions.

In the cement mortar / concrete composition according to claim 2, the cement mortar / concrete composition contains 70% by mass or more of the C ₁₂ A ₇ mineral phase, 5.0% by mass or less of _{C 3 A, and TiO 2 of Ti.} 1.0 wt% in terms of less, Fe is equal to or less than 1.5% by mass Fe _2. O ₃ in terms of a cement mortar and concrete compositions.

Cement mortar and concrete composition of claim 3 wherein the, (1) C ₁₂ and cement rapid hardening additive material containing A ₇ based mineral phase, gypsum and a sulfuric acid alkali compound, a calcium salt, lithium cement carbonate Contains 5 to 40% by mass of C ₁₂ A ₇ series minerals, 0.5 to 1.0 mass% of alkali sulfate compounds (sodium sulfate equivalent), and lithium carbonate (lithium equivalent) / C ₁₂ A ₇ series. the mass ratio of the content of the mineral phase is 0.0005 to 0.03, calcium salt (calcium hydroxide _{terms) / C} 12 _{a 7} system the mass ratio of the content of the mineral phase is 0.03 to 0.4, gypsum ( (Equivalent to anhydrous gypsum) / _{The mass ratio of the content of the C 12} A ₇ series mineral phase is 0.6 to 1.4, and _{the crystallite diameter of the C 12} A ₇ series mineral phase measured by X-ray diffraction is 150 to 500 nm. Contains a cement composition having a lattice constant of 11.940 to 11.975 Å, (2) a lithium salt other than lithium carbonate, and (3) a carbonate, and the lithium is divided by an outer ratio with respect to the mass of the cement composition. The cement mortar-concrete composition is characterized by containing 0.01 to 0.15% by mass of a salt (converted to lithium) and 0.05 to 0.6% by mass of the _{carbonate (converted to CO 3).}

Cement mortar and concrete composition of claim 4, wherein, in the above cement mortar and concrete compositions, the _C 12 _{A 7} based mineral phase _C 11 _A 7 _CaX 2 (X is halogen) and a mixed phase of _C 12 _{A 7} It is a cement mortar / concrete composition characterized by being.

The process according to claim 5 cement mortar and concrete compositions described are (1) the crystallite size of _C was measured by X-ray diffraction 12 _{A 7} mineral phase lattice constant at 150 to 500 nm 11.940 to 11. cement for rapid hardening additive is 975Å, and plaster, and sulfuric acid alkali compound, lithium carbonate, and calcium salts, C ₁₂ a ₇ based mineral 36-55% by weight, sulfuric acid alkali compound (sodium sulfate equivalent) Contains 0.3 to 1.7% by mass, lithium carbonate (lithium equivalent) 0.01 to 1.3% by mass, calcium salt (calcium hydroxide equivalent) 1 to 14% by mass, and gypsum (anhydrous gypsum equivalent). / C ₁₂ A _7- based mineral phase mixed composition for cement mixed so that the mass ratio of the content is 0.5 to 1.2, (2) cement, (3) lithium salts other than lithium carbonate and (4) A carbonate is blended, and the lithium salt other than lithium carbonate and the carbonate are mixed with the total amount of the cement mixture composition and the cement, and the lithium salt (lithium equivalent) is 0.01 to. 0.15 mass%, the carbonate (CO ₃ equivalent), characterized in that the formulated to contain 0.05 to 0.6 wt%, a production method of cement mortar and concrete compositions.

The method according to claim 6 cement mortar and concrete compositions described are (1) the crystallite size of _C was measured by X-ray diffraction 12 _{A 7} mineral phase lattice constant at 150 to 500 nm 11.940-11. cement for rapid hardening additive is 975Å, and plaster, and sulfuric acid alkali compound, lithium carbonate, and calcium salt, and cement, 5 to 40 wt% of C ₁₂ a ₇ minerals, sulphate alkaline compound (sodium sulfate the conversion) comprises 0.5 to 1.0 wt%, lithium carbonate (Li _{conversion) / C} 12 weight ratio of the content of _{a 7} mineral phase 0.0005 to 0.03, calcium salt (calcium hydroxide terms ) / C ₁₂ A ₇ series mineral phase content mass ratio is 0.03 to 0.4, gypsum (anhydrous plaster equivalent) / C ₁₂ A ₇ series mineral phase content mass ratio is 0.6 to 1 A cement composition formulated to be .4, (2) a lithium salt other than lithium carbonate, and (3) a carbonate are blended, and lithium other than lithium carbonate is added to the total amount of the cement composition. the salt with carbonate, the lithium salt (lithium equivalent) 0.01 to 0.15 wt%, that the carbonate (CO ₃ equivalent) formulated to contain 0.05 to 0.6 wt% This is a method for producing a cement mortar / concrete composition.

The method for producing a cement mortar / concrete composition according to claim 7 is the above-mentioned method for producing a cement mortar / concrete composition. by baked to cool at a cooling rate 40 ° C. / min or less at ℃, _C 12 _{a 7} lattice constant mineral phase crystallite diameter _C 12 _{a 7} mineral phase as measured by X-ray diffraction is at 150~500nm Is a method for producing a cement mortar / concrete composition, which is produced as 11.940 to 11.975 Å.

The cement mortar-concrete composition of the present invention has excellent rapid hardness in a low temperature environment, exhibits sufficient strength, is also excellent in workability, and can suppress the occurrence of initial shrinkage cracks due to self-shrinkage. It can be done.

Further, in addition to the above effects, it is possible to secure a certain pot life with a predetermined fluidity, and it is possible to secure workability having excellent pumping property, for example.

Further, the method for producing a cement mortar / concrete composition of the present invention can effectively prepare the cement mortar / concrete composition of the present invention.

In particular, a specific cement admixture can be easily added in an arbitrary amount according to a desired initial strength, together with a lithium salt other than lithium carbonate, a carbonate, etc., while adjusting in the field, or by adding a specific mixture. By adding the cement composition in an arbitrary amount in an arbitrary amount according to the desired initial strength, together with a lithium salt other than lithium carbonate, a carbonate, etc. while adjusting on-site, a design for obtaining the desired rapid hardness on-site is designed. This makes it easy to carry out, and it becomes possible to produce a cement mortar / concrete composition on-site, which is particularly excellent in initial strength development at a low temperature such as 5 ° C. and can suppress initial shrinkage cracks.

It is a figure which shows typically the formwork for carrying out a crack test.

The present invention will be described in the following form, but the present invention is not limited thereto. The cement mortar / concrete composition means a mortar composition or concrete composition before being mixed with water, and the cement mortar / concrete means a mortar or concrete mixed with water.
(First cement mortar / concrete composition)
The first cement mortar and concrete composition of the invention comprises (1) a cement rapid hardening additive material containing C ₁₂ A ₇ based mineral phase, and gypsum, and sulfuric acid alkali compound, a calcium salt and lithium carbonate Containing C ₁₂ A ₇ series minerals 36-55% by mass, alkali sulfate compounds (sodium sulfate equivalent) 0.3-1.7% by mass, lithium carbonate (lithium equivalent) 0.01-1.3% by mass , calcium salt (calcium hydroxide equivalent) containing 1-14 wt%, the mass ratio of the content of gypsum (anhydrite _{equivalent) / C} 12 _{a 7} mineral phase is 0.5 to 1.2, X cement admixture composition crystallite diameter _C 12 _{a 7} mineral phase as measured by ray diffraction is lattice constant 11.940~11.975Å at 150 to 500 nm, (2) cement, (3) other than lithium carbonate The lithium salt (4) carbonate is contained, and 0.01 to 0.15% by mass of the lithium salt (lithium equivalent) is added to the total mass of the cement admixture and cement, and the carbonate is added. salt (CO ₃ basis) containing 0.05 to 0.6 wt%, a cement mortar and concrete compositions.

Preferably, in the first cement mortar-concrete composition, the hard-hardening additive for cement contains 70% by mass or more _{of the C 12} A ₇ mineral phase, 5.0% by mass or less of _{C 3 A, and Ti.} It is desirable that TiO ₂ is 1.0% by mass or less and Fe is 1.5% by mass or less _{in terms of Fe 2.} O _3.
Further, preferably, in the cement mortar / concrete composition, it is desirable that the C ₁₂ A ₇ series mineral phase is a mixed phase of _{C 11} A ₇ CaX ₂ (X is a halogen) and C ₁₂ A _7.

By having the above structure, the cement mortar / concrete composition of the present invention has excellent initial strength development even in a low temperature environment of about 5 ° C., can suppress the occurrence of initial shrinkage cracks, and secures fluidity. Therefore, the workability can be improved.

C ₁₂ A ₇ mineral phase is a first calcium aluminate phases of the cement admixture for composition contained in cement mortar and concrete composition of the present invention, as described above, 36 to 55 wt%, preferably It is contained in an amount of 40 to 52% by mass.
Such C ₁₂ A ₇ based mineral phase is added blended in the preparation of the cement admixture for the composition, it is derived from a cement rapid hardening additive.
The inclusion of C ₁₂ A ₇ based mineral phase, preferably by including in the content, cement mortar and concrete composition of the present invention is sufficiently steep rigid and excellent initial strength can be obtained even at a low temperature At the same time, it is possible to obtain the above-mentioned effect of the present invention having a desired sufficient pot life.
Irwin is not included in the cement admixture.
The content of C ₁₂ A ₇ mineral phase is a calcium aluminate phase in the resultant cement admixture for composition, for example, it can be measured by the following X-ray diffraction / Rietveld method.

_{The C 12} A ₇ series mineral in the cement admixture _{has a crystallite diameter of the C 12} A ₇ series mineral phase measured by X-ray diffraction of 150 to 500 nm, preferably 150 to 300 nm.
When _{the crystallite diameter of the C 12} A ₇ series mineral phase is within such a range, excellent initial strength development and good fluidity that can secure the pot life can be obtained.
The crystallite diameter is a value measured by powder X-ray diffraction, and is a value measured by an X-ray diffraction / Rietveld method (apparatus: D4 Endeavor manufactured by Bruker Co., Ltd., analysis software: Topas).
Tube voltage: 45kV Tube current: 40mA

_{Further, the C 12} A ₇ series mineral in the cement admixture composition has a lattice constant of 11.94 to 11.975 Å of _{the C 12} A ₇ series mineral phase measured by X-ray diffraction.
By setting the lattice constant within such a range, it is possible to secure a predetermined fluidity and have excellent rapid hardness, and to obtain the above-mentioned effect of the present invention.
The lattice constant is a value measured by powder X-ray diffraction, and is a value measured by using an X-ray diffraction / Rietveld method (apparatus: X'Pert MPD manufactured by PANalytical Co., Ltd., analysis software: HighScorePlus). ..
Tube voltage: 45kV Tube current: 40mA

Examples of gypsum (calcium sulfate) in the admixture for cement include anhydrous gypsum, hemihydrate gypsum, dihydrate gypsum, or a mixture thereof.
Such gypsum in cement admixture composition, the mass ratio of the content of the gypsum _{/ C} 12 _{A 7} mineral phase from 0.5 to 1.2, preferably the amount contained such that 0.7-1.1 Included in. However, the gypsum content is an amount calculated as a total amount converted to _{CaSO 4 (anhydrite).}
Further, the content of gypsum in the cement admixture composition can be measured by, for example, the above-mentioned X-ray diffraction / Rietveld method.

Further, as the alkali sulfate compound in the admixture for cement, for example, alkali metal sulfates such as Glauber's salt (sodium sulfate) and potassium sulfate can be exemplified.
The content of the alkali sulfate compound is 0.3 in the cement admixture composition, which is obtained by measuring the amount of Na and the amount of K according to JCAS I-04 and _{converting all of them into the total amount converted to Na 2} SO _4. It is desirable that the content is in an amount of ~ 1.7% by mass, preferably 0.5 to 1.5% by mass.

Further, as the calcium salt in the cement admixture composition contained in the cement mortar / concrete composition, for example, salts that are not sparingly soluble in water such as slaked lime and quick lime can be used, but calcium hydroxide is preferable, and calcium is preferable. It is desirable that all the salts are contained in an amount of 1 to 14% by mass, preferably 2 to 12% by mass in terms of calcium hydroxide.
Further, the cement admixture composition contained in the cement mortar / concrete composition of the present invention contains 0.01 to 1.3% by mass of lithium carbonate in terms of lithium, preferably 0.01 to 1.0% by mass. It is desirable that it be contained.
The content of the calcium salt (calcium hydroxide equivalent) in the obtained mixed composition for cement can be measured by, for example, the above-mentioned X-ray diffraction / Rietveld method, and lithium carbonate (lithium equivalent). The content of can be measured using, for example, ICP emission spectroscopy.

By blending a cement mixture composition containing gypsum, an alkali sulfate compound, a calcium salt and lithium carbonate within the above range, the above effects can be effectively exhibited.

Preferably, the mixed composition for cement may contain fluorine (F), which is derived from the contained hard-hardening additive for cement, and the content thereof is fluorine / C ₁₂ A. _{It is desirable that the content of the 7-} based mineral phase is such that the mass ratio is 0.6 to 4.0% by mass, more preferably 1.0 to 3.5% by mass.
When the amount of F contained is in such a range, it has more excellent initial strength development, it is possible to secure a sufficient pot life, and the above-mentioned effect of the present invention can be more effectively exhibited. ..

Further, the above-mentioned cement admixture composition is preferably preferable because it can be further excellent in strength development for 3 hours by satisfying the following formula.
X = -0.93 (F / Q) -Qa + 11.98 ≧ 0
In the above formula, F represents fluorine content of cement admixture composition (mass%), Qa is the lattice constant of the C ₁₂ A ₇ mineral phase of a cement admixture composition (Å), Q is miscible cement It represents the content (% by mass) of the C ₁₂ A _{7 mineral phase in the composition.}

_{Further, it is desirable that C 3} A is substantially not contained in the above-mentioned cement admixture composition _{, and C 3} A / C ₁₂ A ₇ series minerals ≤ 7 (mass%). desirable.
This is because when C ₃ A increases, _{the content of the C 12} A ₇ series mineral phase decreases, so that sufficient initial strength may not be obtained.

_{Further, it is desirable that Ti, Fe, C 2} S and C ₂ AS are substantially not contained in the above-mentioned cement admixture composition _{, and at most, TiO 2} / C ₁₂ A ₇ ≤ 1.4 (mass). %), _{It is desirable that Fe 2} O ₃ / C ₁₂ A ₇ ≦ 2.0 (mass%). As a result, the initial strength development (3 hours after construction, etc.) is further improved. _{The TiO 2} and Fe ₂ O ₃ in the mixed composition for cement are derived from the contained hard-hardening additive for cement.

The first cement mortar and concrete composition of the present invention, a cement admixture composition having the above structure, and any cement, a lithium salt other than lithium carbonate (Li equivalent), and carbonate (CO ₃ equivalent) containing, 0.05 in outer percentage relative to the total weight of the cement admixture composition and cement, a lithium salt other than lithium carbonate and 0.01 to 0.15 wt% and carbonate (CO ₃ equivalent) Contains 0.6% by mass.

As the cement, any commercially available cement can be applied, for example, early-strength Portland cement, ultra-early-strength Portland cement, ordinary Portland cement, moderate heat Portland cement, low heat Portland cement, sulfate-resistant Portland cement, etc. At least one type selected from fly ash cement, blast furnace cement, silica cement and the like can be exemplified.

Further, as the lithium salt other than lithium carbonate contained in the cement mortar / concrete composition of the present invention, any lithium salt soluble in water can be used, for example, lithium hydroxide, lithium sulfate, lithium chloride. , Lithium bromide, lithium chlorate, lithium nitrate, lithium nitrite, etc. are exemplified, and as the carbonate contained in the above cement mortar / concrete composition, any water-soluble carbonate or hydrogen carbonate is used. For example, sodium carbonate, potassium carbonate, ammonium carbonate, sodium hydrogen carbonate, calcium hydrogen carbonate and the like are exemplified.
However, in the present invention, the "carbonate" does not include lithium carbonate.

By having the above-mentioned structure, the cement mortar-concrete composition of the present invention is excellent in initial strength development, can suppress the occurrence of initial shrinkage cracks, and can also secure fluidity.

The first cement mortar-concrete composition of the present invention contains, for example, a water reducing agent (alkylallyl sulfonic acid type, naphthalene sulfonic acid type, melamine sulfonic acid type), as long as it does not impair the above effects. , Polycarboxylic acid type, AE water reducing agent, high performance water reducing agent, high performance AE water reducing agent), liquid or powder admixture, fine aggregate (river sand, sea sand, mountain sand, crushed sand and these It is also possible to contain coarse aggregate (river gravel, sea gravel, crushed stone and a mixture thereof) and the like.

(Second cement mortar / concrete composition)
The second cement mortar and concrete composition of the present invention, _{(1) C} 12 _{A 7} mineral 5 to 40 wt%, including sulfuric acid alkali compound (sodium sulfate equivalent) 0.5 to 1.0 wt%, The mass ratio of the content of lithium carbonate (converted to lithium) / C ₁₂ A ₇ series mineral phase is 0.0005 to 0.03, and the mass ratio of the content of calcium salt (converted to calcium hydroxide) / C ₁₂ A ₇ series mineral phase ratio 0.03 to 0.4, the mass ratio of the content of gypsum (anhydrite _{converted) / C} 12 _{a 7} mineral phase is 0.6 to 1.4, _{C 12} a as measured by X-ray diffraction _{A cement composition containing a crystallite diameter of a 7-} based mineral phase of 150 to 500 nm and a lattice constant of 1.194 to 11.975 Å, (2) a lithium salt other than lithium carbonate, and (3) a carbonate. Lithium salt other than lithium carbonate (lithium equivalent) is 0.01 _{to 0.15% by mass by external division and the carbonate (CO 3} equivalent) is 0.05 to 0.6 by external division with respect to the mass of the substance. A cement mortar-concrete composition containing% by mass.

Preferably, also in the second cement mortar-concrete composition of the present invention, the C ₁₂ A ₇ series mineral phase is a mixed phase of _{C 11} A ₇ CaX ₂ (X is halogen) and C ₁₂ A _7. Is desirable.

Since the second cement mortar / concrete composition of the present invention has the above structure, it is excellent in initial strength development at low temperature, can suppress the occurrence of initial shrinkage cracks, secures fluidity, and is workable. Can also be improved.

As the cement contained in the cement composition contained in the second cement mortar / concrete composition of the present invention, the same cement as the cement used in the first cement mortar / concrete composition can be exemplified. ..

Moreover, _C 12 _{A 7} mineral phase is a calcium aluminate phases of the cement composition, as described above, 5 to 40 wt%, preferably from 5 to 36 wt%, more preferably 10 to 30 mass% It is contained.
Such C ₁₂ A ₇ based mineral phase is added blended in the preparation of the cement composition, is desirably derived from a cement rapid hardening additive.
The inclusion of C ₁₂ A ₇ based mineral phase, preferably by including in the content, with sufficient rapid hardening and excellent initial strength can be obtained, having a sufficient pot life desired. It is possible to obtain the above effects of the present invention.
Irwin is not included in the cement composition.
The content of C ₁₂ A ₇ mineral phase is a calcium aluminate phases in the cement composition is, for example, can be measured by the following X-ray diffraction / Rietveld method.

_{The C 12} A ₇ series mineral in the cement composition has _{a crystallite diameter of the C 12} A ₇ series mineral phase measured by X-ray diffraction of 150 to 500 nm, preferably 150 to 300 nm.
When _{the crystallite diameter of the C 12} A ₇ series mineral phase is within such a range, excellent initial strength development and good fluidity that can secure the pot life can be obtained.
The crystallite diameter is a value measured by powder X-ray diffraction, and is a value measured by an X-ray diffraction / Rietveld method (apparatus: D4 Endeavor manufactured by Bruker Co., Ltd., analysis software: Topas).
Tube voltage: 45kV Tube current: 40mA

_{Further, the C 12} A ₇ series mineral in the cement composition has a lattice constant of 11.94 to 11.975 Å of _{the C 12} A ₇ series mineral phase measured by X-ray diffraction.
By setting the lattice constant within such a range, it is possible to secure a predetermined fluidity and have excellent sharpness.
The lattice constant is a value measured by powder X-ray diffraction, and is a value measured by using an X-ray diffraction / Rietveld method (apparatus: X'Pert MPD manufactured by PANalytical Co., Ltd., analysis software: HighScorePlus). ..
Tube voltage: 45kV Tube current: 40mA

Examples of the gypsum (calcium sulfate) contained in the cement composition include anhydrous gypsum, hemihydrate gypsum, dihydrate gypsum, or a mixture thereof.
Such gypsum in the cement composition, the mass ratio of the content of the gypsum _{/ C} 12 _{A 7} based mineral phase 0.6 to 1.4, preferably included in a content such that 0.8 to 1.3 Is done. However, the gypsum content is an amount calculated as a total amount converted to _{CaSO 4 (anhydrite).}
The content of gypsum in the cement composition can be measured by, for example, the above-mentioned X-ray diffraction / Rietveld method.

Examples of the alkali sulfate compound contained in the cement composition include alkali metal sulfates such as Glauber's salt (sodium sulfate) and potassium sulfate.
The content of such an alkali sulfate compound is 0.5 to 1 in the cement composition, which is obtained by measuring the amount of Na and the amount of K according to JCAS I-04 and _{converting all of them into Na 2} SO _{4 equivalent.} It is desirable that it is contained in an amount of 0.0% by mass, preferably 0.6 to 1.0% by mass.
By containing gypsum or an alkaline sulfate compound within the above range, the above-mentioned effect of the present invention can be more effectively exhibited.

Further, as the calcium salt in the cement composition, for example, salts such as slaked lime and quick lime that are not sparingly soluble in water can be used, but calcium hydroxide is desirable.
Such calcium salt, in the cement composition, a calcium salt (calcium hydroxide _{terms) / C} 12 _{A 7} system the mass ratio of the content of the mineral phase is 0.03 to 0.4, preferably 0.05 to 0.35 It is contained in such a content as. However, the calcium salt content is an amount calculated as a total amount converted to calcium hydroxide.

Lithium carbonate cement composition, the weight ratio of the lithium carbonate (Li _{terms) / C} 12 _{A 7} based content mineral phases 0.0005 to 0.03, and preferably no greater 0.0005 to 0.025 It is contained in a high content.
The content of calcium salt (calcium hydroxide equivalent) in the cement composition can be measured by, for example, the above-mentioned X-ray diffraction / Rietveld method, and the content of lithium carbonate (lithium equivalent) is For example, it can be measured using ICP emission spectroscopy.

The second cement mortar-concrete composition of the present invention obtained by containing a cement composition containing gypsum, an alkali sulfate compound, a calcium salt and lithium carbonate within the above range effectively exhibits the above effects. It becomes possible to do.

Preferably, there may be included in the cement composition fluorine (F) is, the content thereof, the weight ratio of the content of the fluorine _{/ C} 12 _{A 7} mineral phase 0.8 to 4.0 (mass %), More preferably 1.5 to 3.5 (% by mass).
For example, the fluorine content in Portland cement, which is a raw material, is at most 0.05% by mass, which is the same as the fluorine content (for example, about 0.5 to 3.0% by mass) contained in the hard-hardening additive for cement. Since the amount of fluorine contained in the obtained cement composition is extremely small, most of the fluorine contained in the obtained cement composition is derived from the following hard-hardening additive for cement, which is a raw material for production.
By setting the amount of F contained in such a range, it is possible to have more excellent initial strength development and to secure a sufficient pot life.

The cement composition preferably has the following formula: C ₁₂ A ₇ series mineral phase lattice constant (Å) ≤ [(0.05-fluorine content (mass%))] / C ₁₂ A ₇ series. It is particularly desirable to satisfy the content of the mineral phase (% by mass) + 11.98, and by having such a relationship, it is possible to have excellent initial strength development and to secure the pot life.

The above cement composition, Ti is desirably substantially _free, the content of _C 12 _{A 7} based mineral phase (wt%) ≧ 83 × (TiO ₂ content (wt%) - 0.3 ) Is desirable.

The cement composition used in the present invention may contain various organic substances such as coagulation modifiers (Rig human sulfonic acid type, oxycarboxylic acid type, saccharides, etc.), if necessary, as long as the above effects of the present invention are not impaired. Alkali metal salts and alkalinity metal salts of acids or organic acids) and water reducing agents (alkylallyl sulfonic acid type, naphthalene sulfonic acid type, melamine sulfonic acid type, polycarboxylic acid type, AE water reducing agent, high performance water reducing agent, high It is also possible to add an admixture such as (including a performance AE water reducing agent).

The second cement mortar-concrete composition of the present invention contains a cement composition having the above composition, a lithium salt other than lithium carbonate, and a carbonate, and thus has excellent initial strength development at low temperatures. , The occurrence of initial shrinkage cracks can be suppressed, and fluidity can be ensured.

As the lithium salt other than lithium carbonate and the carbonate contained in the second cement mortar / concrete composition of the present invention, the same ones as those of the first cement mortar / concrete composition of the present invention can be used. can, the content thereof, relative to the weight of the cement composition, in outer percentage, lithium salt other than lithium carbonate (the lithium basis) 0.01 to 0.15% by weight and a carbonate to (CO ₃ equivalent) 0 .05 to 0.6% by mass.

Further, in the second cement mortar-concrete composition of the present invention, if necessary, for example, a water reducing agent (alkylallyl sulfonic acid type, naphthalene sulfonic acid type, melamine sulfone), as long as it does not impair the above effects. Acid-based, polycarboxylic acid-based, AE water reducing agents, high-performance water reducing agents, high-performance AE water reducing agents), liquid or powder admixtures, and fine aggregates (river sand, sea sand, mountain sand, crushed sand, etc.) These mixtures), coarse aggregates (river gravel, sea gravel, crushed stones and mixtures thereof) and the like can be blended.

(Preparation of first cement mortar / concrete composition)
First method of manufacturing a cement mortar and concrete composition of the invention comprises (1) a cement rapid hardening additive material containing C ₁₂ A ₇ based mineral phase, and gypsum, and sulfuric acid alkali compound, lithium carbonate, a calcium _{salt, C} 12 _{a 7} based mineral 36-55% by weight, sulfuric acid alkali compound (sodium sulfate equivalent) 0.3 to 1.7 wt%, lithium carbonate (Li equivalent) 0.01. 3 wt%, calcium salt (calcium hydroxide equivalent) is contained 1 to 14% by mass, the mass ratio of the content of gypsum (anhydrite _{equivalent) / C} 12 _{a 7} based mineral phase with 0.5 to 1.2 A certain cement admixture, (2) cement, (3) lithium carbonate other than lithium carbonate, and (4) carbonate are added to the total mass of the cement admixture and cement. formulated to contain (lithium equivalent) of 0.01 to 0.15% by weight and a carbonate to (CO ₃ basis) 0.05 to 0.6 wt%, a production method of cement mortar and concrete compositions.

_{The C 12} A ₇ series mineral which is the calcium aluminate phase in the cement mortar / concrete composition produced according to the present invention is derived from the above-mentioned hard-hardened admixture for cement, and the C ₁₂ A ₇ series mineral phase. the crystallite diameter of the _C 12 _{a 7} mineral phase as measured by X-ray diffraction lattice constants 150~500nm is 11.940～11.975Å.

Further, in the method for producing an admixture for cement used in the first cement mortar / concrete composition of the present invention, a hard-hardening additive for cement, gypsum, an alkali sulfate compound, a calcium salt and lithium carbonate are mixed. It is prepared to have the above-mentioned specific composition of the above-mentioned mixture composition for cement.
The production method is not particularly limited, but specifically, a specific hard-hardening additive for cement, gypsum, an alkali sulfate compound, a calcium salt, and lithium carbonate are used, and C ₁₂ A ₇ minerals have a mass of 36 to 55 mass. %, Alkali sulfate compound (converted to sodium sulfate) is 0.3 to 1.7% by mass, lithium carbonate (converted to lithium) is 0.01 to 1.3% by mass, and calcium salt (converted to calcium hydroxide) is 1 to 14%. wt%, gypsum weight ratio of (anhydrite converted) / C ₁₂ a ₇ based content mineral phase is formulated such that 0.5 to 1.2, and uniformly mixed, the cement admixture composition To prepare.

Specifically, the hard-hardening additive for cement to be blended in the cement admixture is a calcium raw material such as fresh lime and limestone, an aluminum raw material such as aluminum hydroxide and alumina, bauxite and band shale, and fluorine such as fluorite. Raw materials, magnesium raw materials such as dolomite to be blended as needed, etc. are mixed and crushed, or crushed and mixed, and this powder mixture is molded to obtain a molded product, which is heated by an electric furnace or the like. Bauxite is fired in a furnace and cooled to prepare a hard-hardening additive for cement.
In addition, those which are raw materials of Ti and Fe contained in the obtained hard-hardening additive for cement (for example, red iron oxide) are not positively blended. Ti and Fe contained in the hard-hardening additive for cement to be blended may be contained as an impurity in the compounding raw material, and may be contained as a result, but are not positively contained.

Furthermore, cement rapid hardening additive to be incorporated in the production of the cement admixture composition, crystallite diameter _C 12 _{A 7} mineral phase as measured by X-ray diffraction is 150 to 500 nm, preferably 150~300nm , A fast-hardening additive having a lattice constant of 11.940 to 11.975 Å.
Crystallite size of C ₁₂ A ₇ mineral phase, the cement rapid hardening additive to such a range lattice constant comprises the cement admixture composition, by further comprising the cement mortar and concrete compositions, the hydrated active While promoting, shrinkage due to hydration activity can be reduced, and excellent initial strength development and good fluidity that can secure pot life can be obtained.
The crystallite diameter and the lattice constant are values measured by the same measuring method as described above.

In particular, preferably, cement rapid hardening additive comprises C ₁₂ A ₇ mineral phase 70 mass% or more, not including the C 3 _A Ti and Fe substantially, even included as impurities in the raw material C ₃ A is 5.0% by mass or less, Ti is 1.0% by mass or less in terms of _{TiO 2 , Fe is 1.5% by mass or less in terms of Fe 2} O ₃ , and F is 0.5 to 3 by mass. It is desirable that the material is a fast-hardening additive containing 0.0% by mass.
When C ₃ A exceeds 5.0% by mass, the content of the C ₁₂ A ₇ series mineral phase decreases, so that sufficient rapid hardness cannot be obtained by addition in the field, and the initial strength decreases. There is.

_{Further, C 2} S and C ₂ AS are substantially not contained in the hard-hardening additive for cement containing the C ₁₂ A ₇ series mineral phase as a main component and having a C ₃ A content of a certain level or less. desirable.
The term "substantially free" means that these mineral phases are not prevented from being produced by _{SiO 2, which is an impurity contained in the raw material, and are not actively produced and contained.} It is desirable that the total content of C ₂ S and C ₂ AS is at most 10% by mass or less.
This allows the content of C ₁₂ A ₇ mineral phase is a calcium aluminate phase in order not to reduce the above range.

Incidentally, such a cement rapid hardening additive, as described below, from 1250 to 1,400 ° C., preferably by being prepared by firing at 1300 to 1,360 ° C., _{C 3} S is not that most generated, substantially Not included. Further, since _{Fe 2} O ₃ in the cement quenching additive _{is 1.5% by mass or less, C 4} AF is hardly produced and is substantially not contained.

Further, it is desirable that the hard-hardening additive for cement does not positively contain Ti and does not substantially contain Ti.
Substantially not contained means that Ti does not prevent the case where it is produced by impurities contained in the raw material, and does not mean that Ti is positively contained.
For example, the Ti content is 1.0% by mass or less, preferably 0.5% by mass or less in terms of _{TiO 2 oxide.}
That is, since the hard-hardening additive for cement does not require the formation of a certain amount of melt phase, it is not necessary to positively contain Ti related to the formation of the melt phase.
By substantially not containing TiO ₂ and setting the content at most to the above-mentioned content or less, the initial strength development (3 hours after construction, etc.), which is rapid hardness, is excellent.
When including more than 1.0 mass% of Ti in terms of TiO _{2, C 3} A ends up generating more than 5.0 mass%, no effect is obtained of the present invention.

Further, it is desirable that the hard-hardening additive for cement does not positively contain Fe and does not substantially contain Fe.
Substantially not contained means that Fe does not prevent the case where it is produced by impurities contained in the raw material, and it is not positively contained.
For example, the Fe content is 1.5% by mass or less, preferably 1.0% by mass or less in terms of _{Fe 2} O _{3 oxide.}
That is, since the hard-hardening additive for cement does not require the formation of a certain amount of melt phase, it is not necessary to positively contain Fe, which is related to the formation of the melt phase.
When the Fe ₂ O ₃ contains more than the content, C ₁₂ lattice constant of A ₇ mineral phase is increased, it becomes possible to initial strength development is steeper rigid (3 hours after installation, etc.) is poor, less Is more preferable.

Further, it is desirable that the hard-hardening additive for cement further contains 0.5 to 3.0% by mass, preferably 1.0 to 2.5% by mass of F.
By setting the content of F contained in the hard-hardening additive for cement within the above range, the C ₁₂ A ₇ series mineral phase is stably generated, and _{the lattice constant of the C 12} A ₇ series mineral phase becomes the appropriate range. The hydration activity can be enhanced, and by including the hard-hardening additive for cement in the cement mortar / concrete composition, the above-mentioned effect of the present invention can be more effectively exhibited.

The hard-hardening additive for cement is obtained by pulverizing and mixing the compounding raw materials and molding the mixed powder to obtain a molded product at a temperature of, for example, 1.25 to 1400 ° C., preferably 1300 to 1360 ° C. It can be produced by firing for 5 to 3 hours and then cooling at a cooling rate of 40 ° C./min or less, preferably 5-40 ° C./min. The raw materials are blended so as to have the above content ratio.
The thus obtained cement rapid hardening additive, there is no possible to require the generation of a certain amount of the melt phase, can be hydrated activity of C ₁₂ A _7-based solid solution is expressed sufficiently As described above, Ti, Fe, etc. are substantially not contained, and the content thereof is adjusted so as to be equal to or less than the above content, and the cement is post-added to be excellent in initial strength, which is rapid hardness. Become.

In this way, the molded product obtained by molding the raw material mixed powder is fired and cooled at a cooling rate of 40 ° C./min or less, preferably 5 to 40 ° C./min, so that the C ₁₂ A ₇ system measured by X-ray diffraction is used. crystallite size of the mineral phase is 150 to 500 nm, preferably 150 to 300 _nm, the lattice constant of the _C 12 _{a 7} mineral phase is 11.940～11.975Å, it is possible to produce a cement rapid hardening additive ..

Since the degree of hydration activity, that is, the degree of rapid hardening is different due to the difference in crystallite diameter, in order to secure the pot life and obtain the rapid hardening, calcination is performed at the above-mentioned firing temperature and the above-mentioned cooling. By setting the speed, a hard-hardening additive for cement having a crystallite diameter in the range of 150 to 500 nm can be obtained. Further, by setting the optimum range of 150 to 300 nm, the rapid hardness becomes more excellent.
When the crystallite diameter of the C ₁₂ A ₇ mineral phase is in such a range, such a rapid hardening additive such as cement admixture composition containing were added to cement, obtained cement mortar and concrete is the proper flow It is possible to maintain the property and obtain good initial strength development.

In particular, the hard-hardening additive for cement is preferably used after being pulverized to a ^{brain specific surface area of 4500 cm 2} / g or more, because good hard-hardening may not be obtained if the ^{specific surface area is less than 4500 cm 2 / g.} Is.
Further, if the specific surface area of the brain is too large, the fluidity is adversely affected, the pulverization time is required, the productivity is lowered, and the cost is high ^{. Therefore, 5000 to 7000 cm 2} / g is desirable.
Further, when pulverizing, a pulverizing aid (diethylene glycol, triethanolamine, etc.) may be added.

The cement admixture for composition, the cement rapid hardening additives into powder, and further gypsum, and sulfuric acid alkali compound, a calcium salt and lithium carbonate, C ₁₂ A ₇ based mineral with 36-55 wt% alkali compound is 0.3 to 1.7 mass% sulfuric acid, lithium carbonate 0.01 to 1.3 wt%, 1 to 14% by weight of calcium salt, by weight of the content of the gypsum _{/ C} 12 _{a 7} mineral phases As long as the mixture can be uniformly blended so that the ratio is 0.5 to 1.2, the mixing method is not particularly limited, and any mixing method can be used.

The gypsum content is an _{amount calculated as a total amount converted to CaSO 4} (anhydrous gypsum), and the content of the alkali sulfate compound is the amount of Na or K according to JCAS I-04. All measured and _{converted to Na 2} SO _{4, the} total amount, all calcium salts are the total amount converted to calcium hydroxide, and all lithium carbonate is the amount converted to lithium.

Specifically, even if gypsum, an alkali sulfate compound, a calcium salt and lithium carbonate are mixed in advance and mixed with a rapid-hardening additive for cement, gypsum, an alkali sulfate compound, a calcium salt and lithium carbonate are mixed. And even if the fast-hardening additive for cement is mixed at the same time, any method can be used as long as it can be mixed uniformly.

The first cement mortar / concrete composition of the present invention is produced by blending the cement mixture composition thus obtained, cement, the above lithium salt other than lithium carbonate, and the above carbonate. It is possible to add 0.01 to 0.15% by mass of a lithium salt other than lithium carbonate (lithium equivalent) to the total amount of the cement admixture and cement, and the carbonate (CO ₃ equivalent). Is blended so as to contain 0.05 to 0.6% by mass.

Further, if necessary, for example, a water reducing agent (including an alkylallyl sulfonic acid type, a naphthalene sulfonic acid type, a melamine sulfonic acid type, a polycarboxylic acid type, an AE water reducing agent, a high performance water reducing agent, and a high performance AE water reducing agent). , Liquid or powder admixture, fine aggregate (river sand, sea sand, mountain sand, crushed sand and their mixture), coarse aggregate (river gravel, sea gravel, crushed stone and their mixture), etc. can do.

Further, the method of mixing with water when preparing a cement paste, mortar, concrete or the like using the first cement mortar / concrete composition of the present invention is not particularly limited, and the mixture is blended in a predetermined ratio. Then, it may be mixed using a conventional mixing device.

Specifically, a cement mortar / concrete may be prepared by blending an admixture for cement, an arbitrary cement, a lithium salt other than lithium carbonate, and a carbonate together with water, or an admixture for cement. Even if cement mortar / concrete is prepared by blending the composition, cement, a lithium salt other than lithium carbonate, carbonate, and water in advance, any method can be used as long as it can be mixed uniformly. It doesn't matter.
In particular, it is desirable that the lithium salt other than lithium carbonate and the carbonate are dissolved in advance in the water to be blended when preparing the cement mortar / concrete.
In addition, the above-mentioned admixtures and aggregates added as needed may be added at the same time as cement or the like if they can be mixed uniformly, or may be added sequentially, or when kneaded with water when preparing mortar or the like. It is not particularly limited whether it is added to or by any addition method.

The cement mortar / concrete of the present invention thus obtained has excellent initial strength development even in a low temperature environment, can suppress the occurrence of initial shrinkage cracks, secures fluidity, and improves workability. It can also be secured.

(Second method for manufacturing cement mortar / concrete composition)
Second method for manufacturing a cement mortar and concrete composition of the present invention, _{(1) C} 12 _{A 7} mineral 5 to 40 mass%, 0.5-1.0 mass sulfuric acid alkali compound (sodium sulfate equivalent) %, Lithium carbonate / C ₁₂ A ₇ series mineral phase content mass ratio 0.0005 to 0.03, calcium salt (calcium hydroxide equivalent) / C ₁₂ A ₇ series mineral phase content mass ratio There 0.03 to 0.4, the mass ratio of the content of the gypsum _{/ C} 12 _{a 7} mineral phase is 0.6 to 1.4, crystals of _C 12 _{a 7} mineral phase as measured by X-ray diffraction A cement composition having a child diameter of 150 to 500 nm and a lattice constant of 11.940 to 11.975 Å, (2) a lithium salt other than lithium carbonate, and (3) a carbonate are externally divided with respect to the cement composition. in the lithium salt (lithium equivalent) 0.01 to 0.15 mass%, the carbonate (CO ₃ equivalent) is formulated to contain 0.05 to 0.6 wt%, cement mortar and concrete composition It is a manufacturing method of goods.

_{The C 12} A ₇ series mineral which is the calcium aluminate phase in the cement mortar / concrete composition produced according to the present invention is derived from the above cement composition, and the C ₁₂ A ₇ series mineral phase is X-ray. crystallite size of _C 12 _{a 7} mineral phase as measured by diffraction grating constants 150~500nm is 11.940～11.975Å.

Further, the cement composition used in the method for producing the second cement mortar / concrete composition of the present invention is prepared by mixing a hard-hardening additive for cement, gypsum, an alkali sulfate compound, a calcium salt, lithium carbonate and cement to form the above cement. The composition is prepared to have the above specific composition.
Although their preparation is not particularly limited, specifically, for example, and the specific cement rapid hardening additive, and gypsum, and sulfuric acid alkali compound, a calcium salt and a lithium carbonate, a cement, C ₁₂ A ₇ system mineral 5 to 40 mass%, wherein the sulfuric acid alkali compound 0.5 to 1.0 mass%, the mass ratio of the content of lithium carbonate _{/ C} 12 _{a 7} mineral phase 0.0005 to 0.03, hydroxide The mass ratio of the content of the calcium / C ₁₂ A ₇ series mineral phase should be 0.03 to 0.4, and the mass ratio of the content of the gypsum / C ₁₂ A ₇ series mineral phase should be 0.6 to 1.4. To prepare a cement composition by mixing evenly with gypsum.

The hard-hardening additive for cement blended in the above-mentioned cement composition is the same as the hard-hardening additive for cement used when preparing the first cement mortar-concrete composition of the present invention.

In the cement composition, the hard-hardening additive for cement is powdered, and the gypsum, the alkali sulfate compound, the calcium salt and lithium carbonate, and any commercially available cement are added to C. ₁₂ a ₇ mineral 5 to 40 wt%, including sulfuric acid alkali compound (sodium sulfate equivalent) 0.5 to 1.0 wt%, lithium carbonate (Li _{conversion) / C} 12 _{a 7} based content of mineral phases mass ratio is 0.0005 to 0.03, calcium salt (calcium hydroxide _{terms) / C} 12 _{a 7} system the mass ratio of the content of the mineral phase is 0.03 to 0.4, gypsum (anhydrite terms) / C if it is possible to mass ratio of the content of ₁₂ a ₇ based mineral phase is uniformly mixed so that 0.6 to 1.4, in particular its mixing method is not limited, it is possible to use any mixing method Is.

Specifically, the cement composition can be obtained by preliminarily blending gypsum, an alkali sulfate compound, a calcium salt, lithium carbonate, and a hard-hardening additive for cement, and even if cement is added and mixed, the gypsum and alkali sulfate can be mixed. Even if the compound, calcium salt, lithium carbonate, hard-hardening additive for cement and cement are mixed at the same time, any method can be used as long as they can be mixed uniformly.
In addition, the above-mentioned admixtures and aggregates added as needed may be added at the same time as cement or the like if they can be mixed uniformly, or may be added sequentially, or when kneaded with water when preparing mortar or the like. It is not particularly limited whether it is added to or by any addition method.

A cement mortar / concrete composition can be produced by blending the cement composition thus obtained, the above-mentioned lithium salt other than lithium carbonate, and the above-mentioned carbonate so as to have the above-mentioned content ratio.
Further, as described above, if necessary, for example, a water reducing agent (alkylallyl sulfonic acid type, naphthalene sulfonic acid type, melamine sulfonic acid type, polycarboxylic acid type, AE water reducing agent, high performance water reducing agent, high performance AE). (Including water reducing agents), liquid or powder admixtures, fine aggregates (river sand, sea sand, mountain sand, crushed sand and mixtures thereof), coarse aggregates (river gravel, sea gravel, crushed stones and their mixture). Mixture) and the like can also be blended.

For cement mortar / concrete, for example, even if a cement mortar / concrete is prepared by blending a cement composition, a lithium salt other than lithium carbonate, and a carbonate together with water, the cement composition and lithium carbonate can be prepared in advance. Even if a cement mortar / concrete is prepared by blending a mixture of a lithium salt other than the above, a carbonate, and water, any method may be used as long as it can be mixed uniformly.
In particular, it is desirable that the lithium salt other than lithium carbonate and the carbonate are dissolved in water to be mixed in advance when preparing cement mortar / concrete.
In addition, the above-mentioned admixtures and aggregates added as needed may be added at the same time as cement or the like if they can be mixed uniformly, or may be added sequentially, or when kneaded with water when preparing mortar or the like. It is not particularly limited whether it is added to or by any addition method.

The second cement mortar / concrete thus obtained has excellent initial strength development even in a low temperature environment of about 5 ° C., can suppress the occurrence of initial shrinkage cracks, and secures fluidity. It is also possible to ensure workability.

The present invention will be described with reference to the following examples, comparative examples and test examples.
_{1) Preparation of hard-hardening additives for cement CaCO 3} , SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , MgO, TiO ₂ , CaF ₂ so that the target chemical composition of the hard-hardening additives for cement is shown in Table 1. The raw materials for the fast-hardening additive for each cement were prepared by mixing and pulverizing each of the reagents of the above. Here, SiO ₂ , Fe ₂ O ₃ , and TiO ₂ are calcium oxide raw materials such as quicklime, silicon dioxide, and limestone, aluminum hydroxide, alumina, and bauxite when actually producing a hard-hardening additive for cement in an actual machine. When aluminum raw materials such as bauxite and bauxite, fluorine raw materials such as bauxite, and magnesium raw materials such as dolomite to be blended as necessary are used, SiO ₂ , Fe ₂ O ₃ , and TiO ₂ may be contained as impurities as a result. Therefore, it is used assuming such a case (it is not intended to be actively contained).

Each of the above-mentioned hard additive raw materials for cement was pressure-molded, and each molded body was fired in an electric furnace at 1300 ° C. for 30 minutes, and then cooled at each cooling rate shown in Table 2, and each of them shown in Table 2. A hard-hardening additive for cement was obtained.

2) _{Measurement of content of TiO 2} , Fe ₂ O ₃ , F component, etc. JIS R 5204 of each of the obtained rapid-hardening additives for cement using a fluorescent X-ray analyzer (manufactured by PANalytical Co., Ltd .; Axios). _{The content ratio of the contained TiO 2,} Fe ₂ O _3, F component, etc. was measured by the analysis according to the above.
These results are shown in Table 2.

3) Mineral analysis of hard-hardening additives for cement (C ₁₂ A ₇ series and C ₃ A)
Using the X-ray diffraction / Rietveld method (apparatus: PANalytical X'Pert MPD, analysis software: HighScorePlus), the obtained hard-hardening additives for cement were used to obtain C ₁₂ A ₇ series and C ₃ A minerals. The content ratio and the lattice constant of the crystals of the _{C 12} A _{7 series mineral phase were measured.} Tube voltage: 45kV Tube current: 40mA
The results are shown in Table 2. Here, the lattice constant of the crystal of _{the C 12} A ₇ series mineral phase was measured using the crystal structure of _{C 11} A ₇ CaF _2.

The crystallite diameter of the crystals of the C ₁₂ A ₇ series mineral phase is determined by the X-ray diffraction / Rietveld method (device: D4 Endeavor manufactured by Bruker, analysis software: Topas) using _{the C 11} A ₇ CaF _{2 crystal structure.} Measured by. Tube voltage: 45kV Tube current: 40mA
The results are shown in Table 2.

4) Preparation of mixed composition for cement (Examples 1 to 14, Comparative Examples 1 to 15)
Next, the hard-hardening additive for each cement ^{was pulverized to a brain specific surface area of about 5200 ± 200 cm 2} / g to obtain a hard-hardening additive powder for each cement.
Obtained anhydrite powder for cement, anhydrous anhydrite (trade name; non-clave, manufactured by Sumitomo Osaka Cement Co., Ltd.), Na ₂ SO ₄ (reagent), slaked lime (calcium hydroxide: reagent) and lithium carbonate (reagent) ) Was blended in the blending ratios shown in Tables 3 to 5 below to prepare mixed composition compositions for cement.
In Tables 3 to 5, lithium carbonate indicates a value in terms of lithium.

5) Measurement of mineral content (C ₁₂ A ₇ series) _{in the admixture for cement and crystal lattice constant and crystallite diameter of the C 12} A ₇ series mineral phase The same method as described in 3) above. _{The content of the C 12} A ₇ series mineral phase (Q) in each mixture composition for cement, _{the lattice constant of the crystal of the C 12} A ₇ series mineral phase, and the crystallite diameter were measured.
These results are shown in Tables 3-5.
Incidentally, C ₁₂ A ₇ mineral phase of a cement admixture composition, is derived from the cement for rapid hardening additive.

6) Anhydrite / C ₁₂ A ₇ series mineral phase (mass ratio) in the admixture for cement
And C ₁₂ A ₇ mineral phase content of the cement admixture composition which is measured by the above 5), than the amount of anhydrite of the cement admixture composition shown in Table 3-5, each cement _{Anhydrite / C 12} A ₇ series mineral phase (mass ratio) in the mixed composition for use was calculated.
The results are shown in Tables 3-5.

_{7) C 3} A / C ₁₂ A ₇ mineral phase (mass%), TiO ₂ / C ₁₂ A ₇ mineral phase (mass%), Fe ₂ O ₃ / C ₁₂ A ₇ mineral phase (mass%) in the admixture for cement. mass%)
Amounts of C ₃ A, TiO ₂ , Fe ₂ O _{3 in} Table 2 and a blending amount of the hard-hardening additive for cement in the admixture composition for cement in Tables 3 to 5 and the admixture composition for cement in Tables 3 to 5. From the content (mass%) of the C ₁₂ A _{7 mineral phase in the substance, C 3} A / C ₁₂ A ₇ mineral phase (mass%), TiO ₂ / C ₁₂ A ₇ mineral phase (mass%), Fe ₂ The O ₃ / C ₁₂ A ₇ mineral phase (mass%) was calculated. All, C ₃ A / C ₁₂ A ₇ mineral phase ≤ 7 (mass%), TiO ₂ / C ₁₂ A ₇ mineral phase ≤ 1.4 (mass%), Fe ₂ O ₃ / C ₁₂ A ₇ mineral phase It satisfied ≦ 2.0 (mass%). _{The C 12} A ₇ mineral phase, C ₃ A mineral phase, TiO _{2 and} Fe ₂ O ₃ in the admixture for cement are derived from the above-mentioned hard additive for cement.

8) Preparation of cement mortar composition The mixed compositions for cement (Examples 1 to 14 and Comparative Examples 1 to 15) obtained in early-strength Portland cement (PC: manufactured by Sumitomo Osaka Cement Co., Ltd.) and hydroxide were added. Lithium and sodium carbonate were blended in the blending ratios shown in Tables 3 to 5 to prepare each cement mortar composition. In addition, in Tables 3 to 5, lithium hydroxide and sodium carbonate are blended in the ratios shown in Tables 3 to 5 below by external division with respect to the total amount of the mixed composition for each cement and the early-strength Portland cement. Each cement mortar composition was used.

8) Preparation of cement composition (Examples 15 to 32, Comparative Examples 16 to 30)
The hard-hardening additive for each cement ^{was pulverized to a brain specific surface area of about 5200 ± 200 cm 2} / g to obtain a hard-hardening additive powder for each cement.
Obtained anhydrite powder for cement, anhydrous gypsum (trade name; non-clave, manufactured by Sumitomo Osaka Cement Co., Ltd.), Na ₂ SO ₄ (portland: reagent), slaked lime (calcium hydroxide: reagent), lithium carbonate (Reagent) and early-strength Portland cement (PC: manufactured by Sumitomo Osaka Cement Co., Ltd.) were blended to prepare each cement composition having a content ratio as shown in Tables 6 to 8 below.
In Tables 6 to 8, lithium carbonate indicates a value in terms of lithium.

9) Analysis of mineral content in cement composition (C ₁₂ A ₇ series) and _{measurement of crystal lattice constant and crystallite diameter of the C 12} A ₇ series mineral phase The same method as described in 3) above. The content of the C ₁₂ A ₇ series mineral phase (Q) _{in each cement composition, the lattice constant of the crystals of the C 12} A ₇ series mineral phase, and the crystallite diameter were measured.
These results are shown in Tables 6-8.
Incidentally, C ₁₂ A ₇ mineral phase of the cement composition are those derived from the cement for rapid hardening additive.

10) Measurement of gypsum content and calcium salt content in cement composition The content of gypsum and calcium salt in each cement composition is determined by the same method as the XRD / Rietveld method described in 3) above. Each was measured. However, dihydrate gypsum and hemihydrate gypsum were calculated by converting them into anhydrous gypsum, CaSO ₄ amount (gypsum amount), and calcium salt was converted into calcium hydroxide.
The results are shown in Tables 6-8.

11) Measurement of the content of the alkali sulfate compound in the cement composition The content of the alkali sulfate compound in each cement composition is the amount of Na and K according to the method for analyzing the water-soluble component of cement (JCAS I-04). Was measured, and the total amount converted to Na ₂ SO _{4 as Na 2} SO _{4 and K 2} SO ₄ , respectively, was taken as the content of the alkali sulfate compound.
The results are shown in Tables 6-8.

12) Slaked lime (calcium hydroxide) / C ₁₂ A ₇ series mineral phase (mass ratio of content), gypsum / C ₁₂ A ₇ series mineral phase (mass ratio of content), lithium carbonate / C ₁₂ A ₇ series mineral Phase (mass ratio of content)
The content of C ₁₂ A ₇ mineral phase of each cement composition than the value shown in Table 6-8, the content of slaked lime, the content of the gypsum content and lithium carbonate (anhydrite equivalent) (lithium conversion) more, slaked lime (calcium _{hydroxide) / C} 12 _{A 7} based mineral phase (weight ratio: weight%), gypsum (anhydrite _{equivalent) / C} 12 _{A 7} based mineral phase (weight ratio), lithium carbonate (Li conversion) / The C ₁₂ A ₇ series mineral phase (mass ratio: mass%) was calculated.
The results are shown in Tables 6-8.

13) Preparation of cement mortar composition Each of the above cement compositions (Examples 15 to 32, Comparative Examples 16 to 30, Control Example), lithium hydroxide and sodium carbonate were mixed in the blending ratios shown in Tables 6 to 8. Each cement mortar composition was prepared by blending. In addition, in Tables 6 to 8, each cement mortar composition was prepared by blending lithium hydroxide and sodium carbonate in the blending ratios shown in Tables 6 to 8 below by external division with respect to 100 parts by mass of each cement composition. And said. The cement composition as a control example is early-strength Portland cement (PC: manufactured by Sumitomo Osaka Cement Co., Ltd.) itself.
In Tables 6 to 8, lithium hydroxide is converted to lithium and sodium carbonate is converted to _{CO 3.}

14) Preparation of mortar Each cement mortar composition (Examples 1-32, Comparative Examples 1-30, Control Example), fine aggregate (silica sand), water and admixture (Mighty 150: manufactured by Kao Corporation) are as follows. As shown in Table 9, the mixture was mixed and kneaded uniformly to obtain each mortar. Lithium hydroxide and sodium carbonate in the cement mortar composition were previously dissolved in water before use.

15) Intensity measurement and flow value measurement For each of the mortars of Examples 1 to 32, Comparative Examples 1 to 30 and Control Examples obtained above, the intensity at 5 ° C. for 3 hours and the flow value at 5 ° C. were determined by JIS R. It was measured according to 5201.
The results are also shown in Tables 3 to 5 and Tables 6 to 8 above.

16) Crack test Each mortar of Examples 1-32, Comparative Examples 1-30 and Control obtained above was subjected to a crack test at 5 ° C. as follows.
A mortar specimen was prepared according to JSCE-F506 (How to prepare a cylindrical specimen for compressive strength test of mortar or cement paste). However, as shown in FIG. 1, the formwork used was one in which a hole was made in the upper part of the formwork for a cylindrical specimen (φ5 × 10 cm) and bolts were inserted to fix the formwork.
For the evaluation of cracks, the length of cracks generated on the upper surface of the specimen (upper surface of the bolt) after 3 hours of kneading was measured in units of 5 mm (rounded up), and a state of 5 mm or less was accepted.
These results are shown in Tables 3-5 and 6-8.

The cement mortar-concrete composition of the present invention exhibits sufficient strength even in a low temperature environment, exhibits excellent hydration activity and good rapid hardening performance, and can suppress the occurrence of initial shrinkage cracks due to self-shrinkage. It can be applied to various construction works, civil engineering works, road works, and building structures.

Claims (7)

(1) A _{hard-hardening additive for cement containing a C 12 A 7} mineral phase, gypsum, an alkali sulfate compound, a calcium salt and lithium carbonate, and 36 to 55% by mass of the _{C 12} A _{7 mineral.} , Alkali sulfate compound (converted to sodium sulfate) 0.3 to 1.7% by mass, lithium carbonate (converted to lithium) 0.01 to 1.3% by mass, calcium salt (converted to calcium hydroxide) 1 to 14% by mass %, The mass ratio of the content of gypsum (anhydrous gypsum equivalent) / C ₁₂ A ₇ series mineral phase is 0.5 to 1.2, and the crystal of _{C 12} A _{7 series mineral phase measured by X-ray diffraction.} The cement containing an admixture for cement having a child diameter of 150 to 500 nm and a lattice constant of 11.940 to 11.975 Å, (2) cement, (3) a lithium salt other than lithium carbonate, and (4) carbonate. _{The lithium salt (lithium equivalent) is 0.01 to 0.15% by mass, and the carbonate (CO 3} equivalent) is 0.05 to 0.6, based on the total mass of the mixed composition and the cement. A cement mortar-concrete composition comprising mass%. In the cement mortar-concrete composition according to claim 1, the cement mortar / concrete composition contains 70% by mass or more of the C ₁₂ A ₇ mineral phase, 5.0% by mass or less of _{C 3 A, and TiO 2 of Ti.} A cement mortar-concrete composition, characterized in that the conversion is 1.0% by mass or less and Fe is 1.5% by mass or less _{in terms of Fe 2.} O _3. (1) A _{hard-hardening additive for cement containing a C 12 A 7} mineral phase, gypsum, an alkali sulfate compound, a calcium salt, lithium carbonate and cement, and 5 to 5 _{C 12} A _{7 minerals.} 40 wt%, sulfuric acid alkali compound (sodium sulfate equivalent) containing 0.5 to 1.0 mass%, the mass ratio of the content of lithium carbonate (Li _{equivalent) / C} 12 _{a 7} mineral phase 0.0005 0.03 , calcium salt (converted to calcium hydroxide) / C ₁₂ A ₇ series mineral phase content ratio of 0.03 to 0.4, gypsum (converted to anhydrous gypsum) / C ₁₂ A ₇ series mineral phase mass ratio of the content is 0.6 to 1.4, the lattice constant is 11.940~11.975Å crystallite size of _C 12 _{a 7} mineral phase as measured by X-ray diffraction is at 150~500nm It contains a cement composition, (2) a lithium salt other than lithium carbonate, and (3) a carbonate, and the lithium salt (lithium equivalent) is 0.01 to 0.15 with respect to the mass of the cement composition. A cement mortar-concrete composition comprising 0.05 to 0.6% by mass of the carbonate (CO _{3 equivalent).} In the cement mortar-concrete composition according to any one of claims 1 to 3, the C ₁₂ A ₇ series mineral phase is a mixed phase of _{C 11} A ₇ CaX ₂ (X is halogen) and C ₁₂ A _7. Cement mortar / concrete composition characterized by. (1) and the cement rapid hardening additive lattice constant is 11.940~11.975Å crystallite size of _C was measured by X-ray diffraction 12 _{A 7} based mineral phase in 150 to 500 nm, and gypsum, alkali sulfate and compounds, lithium carbonate, and calcium _{salts, C} 12 _{a 7} based mineral 36-55% by weight, sulfuric acid alkali compound (sodium sulfate equivalent) 0.3 to 1.7 wt%, lithium carbonate (Li conversion) Contains 0.01 to 1.3% by mass, calcium salt (converted to calcium hydroxide) to 1 to 14% by mass, and the mass ratio of the content of _{gypsum (converted to anhydrous gypsum) / C 12} A _{7 mineral phase is 0.} .The mixture composition for cement mixed so as to be 5 to 1.2, (2) cement, (3) lithium salt other than lithium carbonate and (4) carbonate are blended, and the cement mixture composition and cement are mixed. in outer percentage relative to the total amount of the, lithium salt other than lithium carbonate and the carbonate, the lithium salt (lithium equivalent) 0.01 to 0.15 mass%, the carbonate (CO ₃ equivalent) 0 .. A method for producing a cement mortar / concrete composition, which comprises blending so as to contain 05 to 0.6% by mass. (1) and the cement rapid hardening additive lattice constant is 11.940~11.975Å crystallite size of X-ray diffraction measured _C 12 _{A 7} based mineral phase in 150 to 500 nm, and plaster, alkali compounds sulfate If, lithium carbonate, and calcium salt, and _cement, 5 to 40 wt% of _C 12 _{a 7} minerals include sulfate alkali compound (sodium sulfate equivalent) 0.5 to 1.0 wt%, lithium carbonate ( Lithium conversion) / C ₁₂ A ₇ series mineral phase content mass ratio is 0.0005 to 0.03, calcium salt (calcium hydroxide equivalent) / C ₁₂ A ₇ series mineral phase content mass ratio is 0 .03～0.4, gypsum (anhydrite _{terms) / C} 12 _{a 7} based cement composition mass ratio of the content is blended so that 0.6 to 1.4 of the mineral phase, (2) coal A lithium salt other than lithium acid and (3) carbonate are blended, and the lithium salt other than lithium carbonate and the carbonate are divided into 0 with respect to the total amount of the cement composition. .01～0.15 mass%, the carbonate (CO ₃ equivalent), characterized in that the formulated to contain 0.05 to 0.6 wt%, the production method of cement mortar and concrete compositions. In the method for producing a cement mortar / concrete composition according to claim 5 or 6, the cement mortar / concrete composition is formed by pulverizing and mixing raw materials, and firing at 1250 to 1400 ° C., and a cooling rate of 40 ° C./ by cooling in minutes or less, produced crystallite diameter _C 12 _{a 7} mineral phase as measured by X-ray diffraction lattice constant of _C 12 _{a 7} based mineral phase in 150~500nm as 11.940~11.975Å A method for producing a cement mortar / concrete composition, which is characterized by being made.

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