JP2002308657A - Quick-hardening admixture and quick-hardening lightweight joint mortar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a quick-hardening admixture which, in the form of a powder, is capable of easily being handled, and also, the gelation of a slurry of which is hardly caused even when the slurry is allowed to stand over a long period of time, and also to obtain a quick-hardening lightweight joint mortar containing the quick-hardening admixture. SOLUTION: The quick-hardening admixture is produced by mixing calcium carbonate and an aluminate together in their respective amounts sufficient to provide a (calcium carbonate)/(aluminate) molar ratio of 1.5/1 to 6/1 to facilitate the handling of the quick-hardening admixture in the form of a powder, wherein further, sodium carbonate is added to the aluminate in an amount sufficient to provide a (aluminate)/(sodium carbonate) molar ratio of 1/1 to 13/1 to obtain such as effect that a slurry of the quick-hardening admixture is hardly gelated even when the slurry is allowed to stand over a long period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quick-hardening material and a quick-setting lightweight filling mortar, for example, a gap between a building and a ground.
Fast-hardening material added to mortar or concrete containing air bubbles particularly filled in voids where water flow exists,
Further, the present invention relates to a quick-hardening lightweight filling mortar containing the quick-hardening material.

[0002]

2. Description of the Related Art Generally, tunnels, bridges, retaining walls, etc.
There is a gap between the ground to be constructed. As a conventional technique for filling the voids, it has been proposed to use a foam mortar containing bubbles, which has a low strength after curing, is low-cost, and can be manufactured in the field, as a backing material. JP-A-5-112911). However, when a large amount of water is present in the void, material separation easily occurs in the bubble mortar due to contact with water,
Bubbles disappeared and the volume decreased, making it difficult to obtain a stable cured foam mortar. Therefore, as a conventional technique for solving this problem, for example, a quick-hardening lightweight filling mortar described in JP-A-7-90837 is known. The quick-setting lightweight filling mortar is a water-soluble aluminum salt such as aluminum sulfate, alum, aluminum chloride, etc., in a foam mortar containing air by adding a foaming agent, in an amount of 0.8 to 4.5 in terms of alumina. It is added in an amount of about% by weight.

[0003]

SUMMARY OF THE INVENTION A fast-setting alloy containing such a conventional aluminum salt and aluminate (the aluminate used here is a strong alkali and has a higher hardness than the aluminum salt). The material was carried to the site in the form of powder, and was mixed in the foam mortar immediately before being injected into the void. As described above, the site where the quick-setting lightweight filling mortar is used is in a high humidity environment. for that reason,
The powdery aluminate was deliquified and easily solidified, and the fast-hardened material was difficult to handle. Therefore, it is conceivable to treat the aluminate as a slurry (water-soluble material). However, the aluminate in a slurry state gels when left for a long time, and another problem occurs in that it is difficult to supply the slurry stably.

[0004] Therefore, the inventor of the present invention has conducted intensive studies,
The deterioration of the handling property of the fast-hardened material due to deliquescence can be solved by mixing calcium carbonate with aluminate in an amount such that the molar ratio of calcium carbonate / aluminate is 1.5 to 6, and the slurry-like speed is reduced. The inventors have found that the gelation of the hard material can be eliminated by mixing sodium carbonate in an amount such that the molar ratio of aluminate / sodium carbonate becomes 1 to 13, and completed the present invention.

[0005]

An object of the present invention is to provide a quick-hardening material and a quick-hardening lightweight filling mortar which can be easily handled in a powder state and hardly cause gelling even when left in a slurry state for a long time. The purpose is.

[0006]

The present invention comprises an aluminate, calcium carbonate and sodium carbonate, wherein the calcium carbonate / aluminate molar ratio is 1.5-6.
The aluminate / sodium carbonate molar ratio is 1 to 13;
Is a fast-hardened material. This fast-hardened material is mainly used as an aluminate as a main raw material, and is mixed with cellular mortar containing air bubbles or concrete. The molar ratio of calcium carbonate / aluminate is 1.5-6. Molar ratio 1.5
If it is less than 10, the quick-hardening property is too strong, and it is necessary to reduce the amount of the fast-hardening material. However, mixing with the foam mortar does not work well. On the other hand, if the molar ratio exceeds 6, the fast-setting property is weakened and the fast-setting lightweight filling mortar is separated when it comes into contact with water. The fineness of the calcium carbonate as the powder is preferably 2500 cm ² / g or more in terms of Blaine specific surface area, or about 5 to 50 μm in terms of 80% passing particle diameter. The addition of calcium carbonate powder suppresses the increase in strength due to cement, prevents solidification due to moisture absorption, and facilitates the handling of fast-hardened materials. Also, by adding calcium carbonate, the solution amount of the quick-hardening material was reduced to 4% of the cellular mortar.
(Volume), and uniformity of the fast-curing lightweight filling mortar after mixing can be achieved.

As the aluminate, sodium aluminate, potassium aluminate and the like can be used. The molar ratio of R ₂ O / Al ₂ O ₃ is usually from 0.8 to
2.6, preferably 1 or 2. The molar ratio of aluminate / sodium carbonate is 1-13. If the molar ratio is less than 1, material separation occurs due to contact with water. In addition, a molar ratio of 1
If it exceeds 3, gelling occurs even if the fast-hardened material slurry is left alone for one hour. Sodium carbonate as powder is Na
_It is 99.0% or more of ₂ CO ₃ and is white powder or granules.

[0008] This fast-hardened material is usually mixed with the cellular mortar in a slurry state immediately before injection. It is preferable to add a binder to the cellular mortar. The quick-curing lightweight filling mortar thus obtained has fluidity within a predetermined time after mixing. Therefore, the work of injecting (filling) into the void is easy, and the mortar itself has viscosity due to the effect of the binder, the material separation is small even in water, and immediately after a predetermined time has elapsed, It has the property of hardening.

According to a second aspect of the present invention, the aluminate is
The quick-hardening material according to claim 1, which is sodium aluminate.

A third aspect of the present invention provides a foam mortar containing bubbles, aluminate, calcium carbonate, and sodium carbonate, wherein the calcium carbonate / aluminate molar ratio is 1.5 to 6, and It is a quick-setting lightweight filling mortar mixed with a quick-hardening material having a molar ratio of acid salt / sodium carbonate of 1 to 13. The foam mortar is a mortar containing air by adding a foaming agent. As a method of including bubbles, for example, a method in which a mortar and a foaming agent are vigorously stirred in a mixer, a method in which a foaming agent in an aqueous solution is stirred together with air inside a foaming machine, and continuously produced as a fresh cream foam And the like.

As the foaming agent, commercially available foaming agents such as surfactants and animal proteins can be used. The amount used is the amount of air in the mortar (bubble amount)
Is about 20 to 70%. This bubble amount is 2
If it is 0% or less, the mortar becomes heavy and the strength becomes too large, which is uneconomical. If it exceeds 70%, the filler becomes unstable in water, which is not preferable. The preferred value of the bubble amount is 30 to 60%. The amount of kneading water when producing the cellular mortar is 70 to 120% in a water / cement ratio. If it is less than 70%, the fluidity is insufficient and a predetermined working time cannot be obtained. If it exceeds 120%, material separation and defoaming occur, and the quality of the foam mortar becomes unstable, which is not preferable. A preferred range is 70 to 100%. Since the mortar itself is viscous when filling the gap portion with the bubble mortar, the mortar itself is a filling material that hardly loses bubbles and has a small volume shrinkage.

The above-mentioned fast-hardened material is generally used as a fast-hardened material slurry to which water is added. In this fast-hardening material slurry,
A binder may be added. By adding a binder, the viscosity of the fast-hardening material slurry increases, material separation hardly occurs,
Handling becomes easy. In addition, the mixing with the foam mortar is facilitated, and the bubbles in the mortar can be prevented from decreasing during kneading. As the binder, commercially available organic binders such as cellulose-based and acrylic-based binders can be used. For example, cellulose ether, methyl cellulose, and the like. The amount of the binder added is 0.1% in terms of the outer ratio of the fast-hardened material.
02 to 0.5% by weight. If it is less than 0.02% by weight,
The amount added is insufficient, and the desired viscosity cannot be obtained. If it exceeds 0.5% by weight, the effect of mixing cannot be obtained because the viscosity is too large. A preferable addition amount is 0.05 to 0.25% by weight.
It is about.

[0013] The amount of water in the quick-hardened material slurry is 50 to 200% in a water / fast-hardened material ratio. If it is less than 50%, the amount of water is too small and the amount of the fast-hardening material slurry is reduced, so that it cannot be mixed well with the cellular mortar. If it exceeds 200%, the amount of water is too large and the gelation is delayed. A preferred water / fast-hardening material ratio is about 100%. The mixing amount of fast-hardening material to cement is 5
-20% by weight. If it is less than 5% by weight, curing (coagulation) is slow, and material separation tends to occur at the time of injection. If it exceeds 20% by weight, the curing will be too fast to secure a predetermined working time. The preferred mixing amount is 5 to 15% by weight. The quick-hardened material slurry is manufactured by mixing a fast-hardened material and a predetermined amount of water with a mixer. A predetermined amount of the obtained quick-hardening material slurry is added to the cellular mortar and mixed with a mixer to produce a quick-setting lightweight filling mortar.

According to a fourth aspect of the present invention, the aluminate is
The quick-setting lightweight filling mortar according to claim 3, which is sodium aluminate.

According to a fifth aspect of the present invention, the foam mortar containing the foam includes cement, fine aggregate, and a binder, and a foaming material obtained by foaming a foaming agent is mixed with these. The quick-hardening lightweight filling mortar according to claim 3 or 4. As cement, "JIS
R5201 ", various Portland cements,
Blast furnace cement, silica cement, fly ash cement, special cement, and a mixture of blast furnace slag (granulated blast furnace slag) and an alkaline substance can be used. The fine aggregate is not limited as long as it is for concrete. The amount of fine aggregate used is, for example, 10 cement.
It is 100 to 400 parts by weight with respect to 0 parts by weight. 100
If the amount is less than part by weight, the amount of cement used is slightly increased, and the price of the filler is slightly increased. If it exceeds 400 parts by weight,
The amount of fine aggregate used is slightly too large, and it is difficult to obtain a predetermined foaming amount.

As the binder, commercially available organic binders such as the above-mentioned cellulose-based and acrylic-based binders can be used. The amount of the binder used is preferably 0.5 to 2.0 parts by weight based on 100 parts by weight of cement. If the amount is less than 0.5 part by weight, the viscosity is slightly insufficient, the material is likely to be separated, and air bubbles are easily removed at the time of construction. If it exceeds 2.0 parts by weight, the viscosity is slightly too high to deteriorate the fluidity, and the price of the filler increases, which is not economical. Depending on the type of the binder, only the surface of the particles dissolves upon contact with water, forming a gel to prevent water from penetrating into the particles, a phenomenon that takes a long time to completely dissolve, so-called "Makoko" occurs. Therefore, it is preferable to take measures to prevent this.

[0017] Regardless of the presence or absence of "makoko" prevention treatment, if premixed with powder such as cement,
You can prevent it. In the production of cellular mortar, first, cement, fine aggregate, binder and water are kneaded with a mixer to produce a mortar having viscosity. On the other hand, a foaming agent is foamed by a foaming machine to produce a foamed material. afterwards,
These mortars and the forming material are mixed to produce a foam mortar.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments. However, the present invention is not limited to this embodiment. FIG. 1 is a schematic view showing the concept of the method for producing a quick-setting lightweight filling mortar of the present invention. Table 1 shows a list of materials used in this example. Table 2 shows the physical properties of calcium carbonate added to the cement and the quick-hardening material. However, each particle size was measured using a laser particle size analyzer (HR850, manufactured by Cirrus). The materials shown in Table 1 are blended at the ratios shown in Tables 3 and 4. Next, in the ready-mixed concrete factory, a predetermined amount of water was added to the cement and the fine aggregate by a tilting mixer and kneaded for 3 minutes. Next, this is carried to the site by a ready-mixed concrete car 10 shown in FIG. 1, and using a drum 11 mounted on a carrier, a binder diluted 10 times with water is added to the mortar,
The mixture was further kneaded at a high speed for 5 minutes to produce a mortar mixed with a binder.

A foaming agent diluted 10-fold with water is foamed by a foaming machine, and this and the mortar mixed with the binder are stirred at a high speed while being put into a ready-mixed concrete car 10.
The mixture was stirred at a high speed for only one minute to produce a foam mortar. The water / cement ratio at this time was as follows:
It is a cement ratio. Therefore, when diluting the foaming agent, it is necessary to previously adjust the amount of water mixed with the cement. On the other hand, using a hand mixer (1300 rpm) manufactured by Makita Denki Seisakusho, the binder is supplied while stirring the water and the fast-hardening material so that the water / fast-hardening material ratio shown in Table 4 is obtained. Thereafter, the mixture was further kneaded for 2 minutes to produce a rapidly hardened material slurry. Next, the foamed mortar discharged from the ready-mixed concrete car 10 is discharged by the first slurry pump 12, while the fast-hard material slurry is discharged by the second slurry pump 13. The foam mortar and the fast-hardened material slurry are joined by a Y-shaped pipe 14 to which the tip of each discharge pipe is connected, and immediately thereafter, are mixed without power by a static mixer 15. Thus, a quick-setting lightweight filling mortar was produced. The obtained quick-curing lightweight filling mortar is filled with water having a diameter of 300 mm and a height of 2 m in which only half of the internal volume is stored.
Was injected into the transparent acrylic tube 16 with a hose and tested by the test methods shown in Table 5. Table 6 shows the results.

As apparent from Table 6, Test Examples 1 to 5
In the quick-hardening lightweight filling mortar of No. 4, calcium carbonate and aluminate were mixed until the molar ratio of calcium carbonate / aluminate became 1.5 to 6, so the handling of the quick-hardened material by deliquescence. Was able to be eliminated by calcium carbonate. In addition, since the sodium carbonate was mixed in such an amount that the molar ratio of aluminate / sodium carbonate was 1 to 13, no gelation occurred even if the rapid hardening material slurry was left for a long time.

[0021]

[Table 1]

[0022]

[Table 2]

[0023]

[Table 3]

[0024]

[Table 4]

[0025]

[Table 5]

[0026]

[Table 6]

[0027]

The quick-hardening material and the quick-hardening lightweight filling mortar according to the present invention are obtained by mixing calcium carbonate in a molar ratio of calcium carbonate / aluminate of 1.5 to 6; Handling becomes easier. In addition, since sodium carbonate is added only in a molar ratio of aluminate / sodium carbonate of 1 to 13, an effect is obtained that gelation is difficult to occur even if the fast-hardened material is left in a slurry state for a long time.

[Brief description of the drawings]

FIG. 1 is a schematic view showing the concept of a method for producing a quick-setting lightweight filling mortar according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Ready-mixed concrete car, 11 drums, 12 1st slurry pump, 13 2nd slurry pump, 14 Y pipe, 15 static mixer, 16 acrylic pipe.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C04B 22:08 C04B 22:10 22:10 24:38 B 24:38) 103: 12 103: 12 111: 70 111: 70 (72) Inventor Mitsuhiko Nishida 1-1, Kurosaki Center, Ube Mitsubishi Cement Research Institute 1-1, Yawatanishi-ku, Kitakyushu-city, Fukuoka Prefecture 1-1 Minamimachi Ube Mitsubishi Cement Research Institute Kurosaki Center F-term (reference) 2D055 JA00 4G012 MB00 MB06 PA02 PB21 PB25 PB31 PB40 PC01 PC06 PC08 PC11 PD01 PD03 PE04

Claims (5)

[Claims] 2. The method of claim 1, wherein the calcium carbonate / aluminate has a molar ratio of 1.5 to 1.5.
6. The molar ratio of aluminate / sodium carbonate is 1 to 13
Is a fast-hardened material. 2. The quick-hardening material according to claim 1, wherein the aluminate is sodium aluminate. 3. A foam mortar containing air bubbles, aluminate, calcium carbonate and sodium carbonate, wherein the molar ratio of calcium carbonate / aluminate is 1.5-6, and said aluminate / sodium carbonate And a fast-hardening lightweight filling mortar obtained by mixing a fast-hardening material having a molar ratio of 1 to 13. 4. The quick-setting, lightweight filling mortar according to claim 3, wherein the aluminate is sodium aluminate. 5. A foam mortar containing bubbles, wherein the foam mortar has cement, fine aggregate, and a binder, and is mixed with a foamed material obtained by foaming a foaming agent. The quick-setting lightweight filling mortar according to claim 4.