JP2001294469A - Ultra rapid hardening, non-shrinkage grout - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide ultra rapid hardening, non-shrinkage grout in which no segregation or no bleeding is caused even when the grout has high flow properties, and which is provided with sufficient rapid hardening properties, non- shrinkage properties and other desirable properties with respect to performing grouting work. SOLUTION: This grout comprises an expansive admixture and a rapid hardening material having a >=4,000 cm2/g Blaine specific surface area, wherein: the rapid hardening material preferably contains calcium aluminate; the expansive admixture preferably contains calcium sulfoaluminate; and when a water-soluble cellulose ether is mixed into the above grout, grout provided with good properties with respect to performing grouting work can be obtained. Fresh mortar of the ultra rapid hardening, non-shrinkage grout has a 2-5 sec J14-funnel flow time value, a 10-40 Pa yield value and a 0.5-3.0 Pa.sec plastic viscosity value and also, a hardened body of 2 hr age the grout has good physical properties, or more specifically, a >=10 N/mm2 compressive strength value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultra-fast-hardening non-shrink grout material mainly used in the field of civil engineering and construction, such as for emergency construction and construction in cold regions.

[0002]

2. Description of the Related Art In general, grout materials are used for a prepacked concrete method, filling into a machine foundation, filling for reinforcing a steel plate, and the like, and good filling properties and high fluidity are required. Furthermore, the grout material is used in constructions where the construction time is restricted, for example, in constructions that require urgency such as roads,
There is a problem that not only the filling property but also the practical strength must be satisfied in a short time. Further, non-shrinkage is required for prevention of separation between the filled grout material and the steel plate and dimensional stability of the machine foundation. However, the conventional ultra-rapid hardening grout material has a problem that material separation and bleeding are apt to occur when the fluidity is high, and the strength expression is low (for example, JP-A No. 12-34154). In addition, there is a problem that the method is not suitable for construction of a sloped part such as a road or a slope.

[0003]

As a result of intensive studies on these problems, the present inventor has found that a super-fast hardening non-shrinking grout material containing a specific quick-hardening material and an expanding material can be used to achieve high fluidity. The inventors have found that there is no material separation or bleeding and that rapid hardening, no shrinkage and workability can be achieved, and the present invention has been completed.

[0004]

That is, the present invention provides (1)
Brain specific surface area 4000cm^Two/ g or more
The ultra-fast hardening non-shrink grout material, (2)
Calcium aluminate, expanding material is calcium sulfor
(1) Ultra-fast curing non-shrinkable graph
Outlet material, (3) water-soluble cellulose ether
(1) or (2) super-hard, non-shrink grout
Wood, (4) J of fresh mortar₁₄Funnel downflow is 2-5
Seconds, in any of (1) to (3).
Ultra-fast curing non-shrink grout material described in (5) Fresh Mo
Lutal yield value is 10 ~ 40Pa, plastic viscosity is 0.5 ~ 3.0Pa ・ s
In any one of (1) to (3).
(6) 2 hours after age
Compressed strength of cured body is 10N / mm ^TwoCharacterized by the above
(1) to (3).
It is a lout material.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail.

[0006] The quick-hardening material used in the present invention is not particularly limited, but comprises a crystalline or amorphous calcium aluminate and gypsum, and produces ettringite by a hydration reaction. Is preferred. Here, calcium aluminate is obtained by mixing a raw material containing calcia and a raw material containing alumina, and performing a heat treatment such as kiln firing or electric furnace melting, and mainly containing CaO and Al ₂ O _3. Is a general term for substances having hydration activity. Specifically, 3CaO.Al ₂ O
_{3 (C 3 A), 12CaO} · 7Al 2 O 3 (C 12 A 7), 5CaO · 3Al 2 O 3 (C 5 A 3),
_{CaO · Al 2 O 3 (CA} ), and crystalline calcium aluminate such as _{CaO · 2Al 2 O 3 (CA} 2), amorphous calcium aluminate having a composition corresponding to these. Of these, the molar ratio of CaO and Al ₂ O ₃ in an amorphous calcium aluminate (C / A) is 1.
A value of 0.1 to 2.0 is preferable, and a value of 1.6 to 1.8 is more preferable.
Furthermore, 11CaO ・ 7Al ₂ O ₃・ CaF containing halogen element
_{2 (C 11 A 7 CaF 2} ), 3CaO · 3Al 2 O 3 · CaF 2 (C 3 A 3 CaF 2) or, sodium, calcium aluminate containing an alkali metal such as potassium may be used.

[0007] Gypsum includes anhydrous gypsum, hemihydrate gypsum, and dihydrate gypsum, and among them, the use of anhydrous gypsum is preferred in terms of quick setting. The amount of gypsum used is 100 calcium aluminate
50 to 300 parts per part is preferred. (Hereinafter, parts represent mass units)

The amount of the fast-hardened material is not particularly limited, but is preferably 5 to 50 parts with respect to 100 parts of cement. Less than 5 parts has little effect. No improvement in effect can be expected.

The grain size of the quick-hardened material is a specific surface area of brane of 4000 cm.
² / g or more is preferable, 4000 to 9000 cm ² / g is more preferable,
5000-7000 cm ² / g is more preferred. Particle size of fast hardened material is 400
Can not be expected to have enough fast curing is less than 0cm ² / g, 9000cm ² /
Even if you use more than g, improvement of the effect can not be expected,
It is uneconomical.

The expanding material used in the present invention is not particularly limited, but includes 3CaO.3Al ₂ O ₃ .CaSO ₄ (C ₃ A ₃ CaSO ₄ )
The main component is calcium sulfoaluminate with a mineral composition shown by, which produces ettringite by hydration, or the main component is free lime (CaO), which generates Ca (OH) ₂ by hydration Is mentioned.

The amount of the expanding material to be used is preferably 1 to 15 parts, more preferably 5 to 10 parts, based on 100 parts of cement. If it is less than 1 part, the effect of non-shrinkage is small, and if it exceeds 15 parts, the amount of expansion is large and it may expand and break.

The particle size of the expanding material is usually determined by the specific surface area of the brane.
Although it is about 2000 to 3000 cm ² / g, the particle size of the expandable material of the present invention is preferably a Blaine specific surface area of 4000 cm ² / g or more, 4000
~9000cm more preferably ² / g, more preferably 5000~7000cm ² / g. If the particle size of the expanding material is less than 4000 cm ² / g, material separation may occur or long-term durability may be deteriorated.
Even if it exceeds cm ² / g, improvement of the effect cannot be expected, and it is uneconomical.

In the present invention, generally used admixtures such as a water reducing agent, a high performance water reducing agent, a high performance AE water reducing agent, and a fluidizing agent are added in order to reduce the amount of water used and increase the fluidity. For example, polyalkyl allyl sulfonate condensate, naphthalene sulfonate condensate, lignin sulfonate condensate, and polycarboxylate, and the like,
One or more of these can be used. The form of use may be either liquid or powder.

The amount of the admixture used is preferably 0.1 to 5 parts based on 100 parts of cement. If the amount is less than 0.1 part, the effect is small, and even if it exceeds 5 parts, the effect cannot be expected to be improved, and it is uneconomical.

[0015] The cement used in the present invention is not particularly limited. However, various types of Portland cement, such as ordinary, early-strength, and ultra-high-strength, and various types of mixture obtained by adding fly ash or blast-furnace slag to these portland cements. Cement and the like.

The ultrafast-hardening non-shrink grout material of the present invention is usually prepared by mixing sand, water with a cement, a fast-hardening material, an expanding material, and an admixture. The cement / fine aggregate ratio of the ultra-fast hardening non-shrink grout material is usually in the range of 1 / 0.5 to 1/3, and is the ratio of water to the binder composed of cement, fast-hardening material, and expansive material. The water / binder ratio is usually preferably in the range of 30 to 50%, but is adjusted according to external factors such as air temperature and water temperature and the required target softness.

The kneading of the ultra-fast hardening non-shrink grout material of the present invention is not particularly limited, but may be a grout mixer,
High-speed hand mixer, forced stirring mixer, etc. are used,
The kneaded mortar is supplied to the construction site by pumping or the like.

Adjustment of the pot life (operable time) of the ultrafast hardening non-shrink grout material of the present invention is performed by adding a setting retarder. Setting retarders (hereinafter, referred to as retarders) are not particularly limited, but usually, inorganic salts such as sodium borate and sodium carbonate, gluconic acid, tartaric acid, and organic acids such as citric acid or salts thereof. Is used as a main component.

Usually, the amount of the retarder used is preferably 0.1 to 5 parts based on 100 parts of cement. If the amount is less than 0.1 part, the effect is small. If the amount exceeds 5 parts, the ultra-fast hardening non-shrink grout material may not be cured.

[0020] Fresh mortar of the ultra-fast hardening non-shrink grout material of the present invention (refers to mortar that has not yet set)
The liquidity, but are not particularly limited, J ₁₄ funnel falling value of preferably 2 to 5 seconds, is less than 2 seconds may segregation is reduced occurrence or intensity expressed, more than 5 seconds And the filling property may be deteriorated.

The application of the ultrafast hardening non-shrink grout material of the present invention is performed at various places such as a flat portion and an inclined portion. In the construction of the flat portion, only the injectability of the ultra-fast hardening non-shrink grout material may be considered, but in the case of a sloped portion, sagging may occur and the filling may not be uniform. In the present invention, it is preferable to mix a water-soluble cellulose ether (hereinafter, simply referred to as cellulose ether) in order to suppress the dripping.

The cellulose ether used in the present invention is:
Although it is not particularly limited, it is preferable to have a property of rapidly dispersing in water but not immediately increasing the viscosity, and having a property of increasing the viscosity when reacting with an alkali in the cement, specifically, Those containing methylcellulose, hydroxypropylmethylcellulose or the like as a main component are exemplified.

The amount of cellulose ether used is
For 100 parts, 0.001 to 0.05 part is preferable, and 0.005 to 0.0
Two parts are more preferred. If the amount is less than 0.001 part, mortar may be sagged. If the amount exceeds 0.05 part, poor filling or poor curing may occur.

The method of adding the cellulose ether to the ultra-fast curing non-shrink grout material is not particularly limited, but it is preferable to add the cellulose ether to water in advance, mix as a slurry water, and knead. In addition, cellulose ether in advance, cement, quick-hardening material, expanding material,
It is also possible to dry blend with fine aggregate and mix with water during construction.

The ultrafast-hardening non-shrink grout material of the present invention has a yield of 10 to 40 Pa and a plastic viscosity of 0.5 to 3.0 Pa · s, which are rheological constants of fresh mortar, from the viewpoint of fillability and workability.
It is preferable that the yield value is 20 to 30 Pa, and the plastic viscosity is
1.0 to 2.0 Pa · s is more preferable. If the yield value or the plastic viscosity is out of these ranges, the filling property and the workability may be deteriorated.

[0026] By adding cellulose ether to the ultra-fast hardening non-shrink grout material of the present invention, the yield value is increased without significantly changing the plastic viscosity, and thixotropic properties are imparted to the fresh mortar, and pumping performance and workability are improved. It is possible to improve the performance. Further, it is preferable to adjust the amount of the cellulose ether to be used depending on the gradient or shape of the construction site.

[0027] The ultra-fast-hardening non-shrink grout material of the present invention exhibits a compressive strength of at least 10 N / mm2 for a ^2- hour-old cured body after kneading, for example, for 2 hours after the completion of construction. Since it reaches practical strength later, it is possible to provide an economical and rational construction such that it can be opened to a normal state early.

[0028]

The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

Example 1 The amount and the particle size of the fast-hardening material and the expanding material with respect to 100 parts of cement were changed as shown in Table 1, and 0.6 part of an admixture, 0.3 part of a retarder and 135 parts of fine aggregate were mixed. Water was added to the mixture so that the ratio of water / (binder = cement + rapid hardening material + expanding material) was 40%, and the mixture was kneaded using a high-speed hand mixer to produce an ultrafast curing non-shrink grout material. . The bleeding, consistency, and handling time of the fresh mortar, and the dimensional change rate of the cured body 7 days of age,
And the compressive strength of 2 hours of material age was measured. Table 2 shows the results.

<Materials Used> Cement: ordinary Portland cement, commercial product Rapid hardening material: non-calcium (C / A (molar ratio) = 1.7) prepared from calcium oxide and alumina as raw materials, melted in an electric furnace, and quenched. A mixture of 100 parts of crystalline calcium aluminate and 150 parts of anhydrous gypsum. This was pulverized to adjust the particle size. Intumescent material: A commercially available product whose main component is a calcium sulfoaluminate with a brane specific surface area of 2800 cm ² / g. This was pulverized to adjust the particle size. Admixture: High performance water reducer based on naphthalene sulfonic acid, commercially available Retarder: Commercially available product mainly composed of organic acid Sand: Lime sand under 5mm Water: Tap water

<Measurement method> Blaine specific surface area: Measured according to JIS R 5201. Consistency: JSCE Concrete Standard Specification (J
According to the measurement of the consistency by J funnel (J _{1 4} funnel) of SCE-F541), it was measured under a stream value. Dimensional change rate: Measured according to JIS A 6202 (B). The dimensional change rate at 7 days of age was measured. Compressive strength: JSCE-G52
It was measured after 2 hours according to 2). Breeding: JSCE Concrete Standard Specification (JSC
The bleeding amount was measured according to E-F533). Pot life: visual judgment (time from kneading until fluidity disappears)

[0032]

[Table 1]

[0033]

[Table 2]

From Table 2, it can be seen that the Blaine specific surface area of the present invention is 4000.
Fresh mortar cm ² / g or more fast hardwood and comprising an expansion member ultra fast curing non-shrink grout material, J ₁₄ funnel falling value indicates 5 seconds or less and good fluidity, no bleeding, dimensions The rate of change is no shrinkage on the expansion side, and it can be seen that the compression strength of the cured body of 2 hours of age is as good as 10 N / mm ² or more.

Example 2 In the fast-hardening material and the intumescent material of Formulation No. G shown in Table 1, the C / A molar ratio of calcium aluminate and the mixing ratio of anhydrous gypsum were changed as shown in Table 3. Except for this, the procedure was the same as in Example 1. Table 4 shows the results.

[0036]

[Table 3]

[0037]

[Table 4]

From Table 4, it can be seen that the C / A molar ratio of the hardened material of the present invention is
Fresh mortar ultra fast curing non-shrink grout which to calcium aluminate 100 parts 1.0 to 2.0 anhydrous gypsum is blended with 50 to 300 parts showed J ₁₄ funnel falling value of 5 seconds or less and good flowability, There is no bleeding, the dimensional change is no shrinkage on the expansion side, and it can be seen that the compressive strength of the cured product of 2 hours of age is as good as 10 N / mm ² or more.

Example 3 A cement 100
An ultra-fast curing non-shrink grout material was produced in the same manner as in Example 1 except that the amount of cellulose ether shown in Table 5 was added to the parts. As a model test, JIS A 1106
Coarse aggregate with a maximum particle size of 40 mm is spread over a 10 × 10 × 40 cm formwork, and the formwork is tilted so that the overall gradient is 55/1000. For the case of injection, J ₁₄ funnel down value, pot life, yield value,
And the plastic viscosity were measured, and the dripping condition and the filling condition after demolding were confirmed. Table 5 shows the results.

<Materials used> Cellulose ether: A commercially available product based on methylcellulose

<Measurement method> Yield value, plastic viscosity: Rheological constant, Murata, Suzuki, Study on flow in grout mortar with slip on pipe wall, Slope pipe grout viscosity measurement described in JSCE Transactions No.384 Measurement using a filling device Filling status: visual drip: visual

[0042]

[Table 5]

From Table 3, it can be seen that the addition of cellulose ether makes it possible for the fresh mortar of the ultra-fast curing non-shrink grout material of the present invention to exhibit good filling properties and an effect of suppressing sagging.

Example 4 Using a fast-hardening material and an intumescent material having the composition No. G shown in Table 1, cement 100
Parts, 30 parts of fast-hardening material, 5 parts of expanding material, 0.5 part of admixture, 0.8 part of retarder
And a mixture of 140 parts of fine aggregate, water was added so that the water / binder ratio became 40%, and the mixture was kneaded with a high-speed hand mixer to produce a super-rapid hardening non-shrink grout material A. Furthermore, 0.005 part of cellulose ether was blended with 100 parts of cement to prepare an ultra-fast-setting non-shrinkable grout material B having a water / binder ratio of 38%. Table 6 shows the physical properties of the ultra-fast curing non-shrink grout material.

[0045]

[Table 6]

As a model test, length 3000 mm × width 600 mm
On one side, the height is 550 mm, the other is 385 mm, and the side walls are trapezoidal (the upper surface is inclined at a gradient of 55/1000), and the coarse aggregate having a maximum particle size of 40 mm used in Example 3 is spread on the wooden formwork. Inject the ultra-rapid hardening non-shrink grout material A from the higher gradient side, and inject 50 mm below the lower gradient surface layer, then inject the ultra-rapid hardening non-shrink grout material B in the same manner, and observe the filling condition and the dripping condition After the curing, the mold was released from the mold to observe the inside. As a result, it was found that sagging did not occur even on a slope having a gradient, and that the filling property into the surface layer portion and the inside was good.

[0047]

According to the present invention, the ultra-fast curing non-shrink grout material is
Even if the fluidity of the fresh mortar is increased, there is no occurrence of material separation or bleeding, not only good filling properties, but also high compressive strength in a short time after curing, and non-shrinkage, economical Thus, a reasonable construction can be provided. Further, by adding the cellulose ether, there is an effect of improving workability such as preventing dripping even on a sloped slope.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C04B 111: 70 C04B 111: 70

Claims (6)

[Claims] 1. An ultra-rapid hardening non-shrink grout material comprising a rapid-hardening material having a specific surface area of 4000 cm ² / g or more and an expanding material. 2. The ultrafast hardening non-shrink grout material according to claim 1, wherein the fast-hardening material contains calcium aluminate and the expanding material contains calcium sulfoaluminate. 3. The non-shrinkable grout material according to claim 1, further comprising a water-soluble cellulose ether. 4. The fresh mortar has a J ₁₄ funnel flow down value of 2
The ultrafast hardening non-shrink grout material according to any one of claims 1 to 3, wherein the time is from 5 to 5 seconds. 5. The yield value of the fresh mortar is 10 to 40 Pa.
4. The ultra-rapid hardening non-shrink grout material according to claim 1, wherein the plastic viscosity is 0.5 to 3.0 Pa · s. 6. The compressive strength of the cured product after 2 hours of age is 10 N /
4. The ultra-fast hardening non-shrink grout material according to claim 1, wherein the grout is not less than mm ² .