JP2001214604A - Grouting material for flowable grout pad construction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grouting material for a flowable grout pad construction method capable of exhibiting high strength, toughness, and form accuracy. SOLUTION: The grouting material is a mixture including at least cement, pozzolanic fine powder, aggregate of 2 mm or finer, water, and water-reducing admixture.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mortar-type pedestal (pad) for providing smoothness in installation of equipment and facilities such as installation of turbines and generators of power plants, and to provide equipment and facilities. The present invention relates to a grout material used in a construction method (flowable grout pad construction method) for installing a sole plate to be used when installing a sole plate.

[0002]

2. Description of the Related Art Heretofore, installation of equipment and facilities such as turbines and generators of a power plant has been performed by squeezing ordinary mortar of solidified form into a mold of a desired shape to form a mortar base (pad). After imparting smoothness, a method of installing a sole plate for installing equipment and facilities has been performed. This method is poor in workability and tends to cause variations in pad quality, so we aim for more stable quality and enhanced properties,
As a method that also improves workability, for example, a water reducing agent or a swelling agent is blended, and after forming a smooth pad using a non-shrink grout material imparted with high filling property and no shrinkage, the sole plate is installed. The method of construction, namely the flowable grout pad method, has rapidly become widespread.

The grout material used in the flowable grout pad method is bleeded at a joint with an upper structure such as a sole plate in order to uniformly transmit a static load of the structure or a dynamic load during machine operation or the like to the foundation. It is necessary to suppress shrinkage as much as possible so that voids due to shrinkage do not occur,
Further, it is required to have high strength and high toughness to be able to withstand the load of the installed object, the dynamic load during the operation of the installed object, the impact load, and the like, and to have good finish accuracy and surface accuracy.
In particular, recently, as the use of this method for new applications (for example, for nuclear power plants) has progressed, the performance required for grout materials has also become more sophisticated. -In addition to toughness, it is necessary to provide particularly high form accuracy expression.

[0004]

However, in the conventional grout material, when the strength and toughness are remarkably improved, the fluidity generally decreases, and the filling property in the mold decreases. As a result, there is a disadvantage that it is difficult to obtain a pad having high shape accuracy such as finish accuracy and surface accuracy.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, grouts represented by the following (1) to (8), which are composed of components different from conventional grout materials. It was found that the material had extremely high strength and toughness, had extremely high fluidity on a mortar basis, was excellent in filling into a mold, and could be easily applied by the flowable grout pad method, and completed the present invention. .

That is, the present invention provides (1) at least cement, fine pozzolanic powder, aggregate having a particle size of 2 mm or less, water,
A grout material for a flowable grout pad method, comprising a compound containing a water-reducing agent. (2) The composition is any one of metal fiber, organic fiber, carbon fiber or 2
The grout material for the flowable grout pad method according to the above (1), wherein the grout material contains at least one kind. (3) The metal fiber is
The grout material for the flowable grout pad method according to the above (2), which is a steel fiber having a diameter of 0.01 to 1.0 mm and a length of 2 to 5 mm. (4) The organic fiber has a diameter of 0.005 to 1.0 mm,
The grout material for the flowable grout pad method according to the above (2), wherein the grout material is at least one fiber selected from vinylon fiber, polypropylene fiber, polyethylene fiber, and aramid fiber having a length of 2 to 30 mm. (5) The carbon fiber has a diameter of 0.005.
The grout material for the flowable grout pad method according to the above (2), wherein the grout material has a length of 1 to 1.0 mm and a length of 2 to 30 mm. (6) The grout material for a flowable grout pad method according to any one of (1) to (5), wherein the composition contains an inorganic powder having an average particle size of 3 to 20 μm. (7) The composition contains needle-like particles and / or plate-like particles having an average particle diameter of 1 mm or less.
The grout material for flowable grout pad method according to any one of (6). (8) The above-mentioned (1) to which the composition contains an expanding material.
(7) The grout material for the flowable grout pad method according to any of (7).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the cement essentially contained in the composition is not particularly limited, and any cement can be used. However, if a particularly high filling property is required, a medium heat Portland cement is preferably used. It is recommended to use Portland cement or low heat Portland cement, and if high early strength is required, use early strength Portland cement.

In the present invention, the pozzolanic fine powder essentially contained in the composition includes silica fume, silica dust, fly ash, slag, volcanic ash, silica sol,
Precipitated silica and the like. In general, silica fume and silica dust are preferable because the average particle size is 1.0 μm or less, and there is no need to pulverize by pulverization. The pozzolanic material with a relatively large particle size is crushed,
The average particle size is adjusted to 1.0 μm or less.

[0009] By blending the pozzolanic fine powder, the hardened grout is densified by the microfiller effect and the cement dispersing effect, and the compressive strength is improved.
On the other hand, when the amount of the pozzolanic fine powder increases, the unit water amount increases. Therefore, the amount of the pozzolanic fine powder to be added is preferably 5 to 50 parts by weight based on 100 parts by weight of the cement.

[0010] In addition, the composition essentially contains aggregate having a particle size of 2 mm or less. In this case, the particle size of the aggregate is a cumulative particle size of 85% (weight), and therefore, aggregates having a particle size of more than 2 mm may be included. When the amount of aggregate having a particle size of 2 mm or less with respect to the total amount of aggregate decreases, the strength decreases. Therefore, the amount of aggregate is preferably 50% by weight or more of the total amount of aggregate.

In the present invention, any one or a mixture of two or more of river sand, land sand, sea sand, crushed sand and quartz sand can be used as an aggregate. The amount of the aggregate is preferably 50 to 250 parts by weight, more preferably 80 to 180 parts by weight, based on 100 parts by weight of cement, from the viewpoint of workability and separation resistance of the mixture, strength after curing and resistance to cracks. More preferred.

Further, the composition of the present invention contains a water reducing agent. The water reducing agent is a high performance water reducing agent or high performance AE
A water reducing agent is preferable, and any one of lignin, naphthalenesulfonic acid, melamine, and polycarboxylic acid components can be used. In particular, a polycarboxylic acid-based high-performance water reducing agent or a high-performance AE water reducing agent can be suitably used. The amount of the high-performance water-reducing agent or high-performance AE water-reducing agent to be added may be 0.5 to 4 in terms of solid content with respect to cement, depending on the fluidity and separation resistance of the mixture, the strength after curing, and the cost. .
0% by weight is preferred.

In the present invention, the water / cement ratio of the composition is determined by the flowability and separation resistance of the grout material,
It is preferably from 10 to 35% by weight, more preferably from 15 to 30% by weight, in view of the strength and durability of the cured product.

In the present invention, it is preferable to use a compound containing at least one of a metal fiber, an organic fiber and a carbon fiber from the viewpoint of increasing the flexural strength of the cured product, and particularly improving the toughness. Examples of the metal fiber include a steel fiber and an amorphous fiber. However, it is particularly recommended because a steel fiber having a high strength is easily obtained and the cost is advantageous. The metal fiber has a diameter of 0.01 to 1.0 mm and a length of 2
5 mm is preferred. If the diameter is less than 0.01 mm, it is easy to be cut by tension, and if the diameter exceeds 1.0 mm, the number of fibers contained in the grout material is reduced at the same compounding amount, so that the strength and especially the toughness are remarkably reduced. Not preferred. Further, when the fiber length exceeds 5 mm, the filling property of the grout material may decrease, and the smoothness may be impaired, which is not preferable. When the fiber length is less than 2 mm, the adhesive strength to the matrix is reduced, and the bending strength is reduced, which is not preferable. The compounding amount is preferably an amount corresponding to less than 2% of the volume of the cured grout after setting, more preferably an amount corresponding to less than 1%. If the blending amount is 2% or more, the fluidity decreases,
It is not preferable because the smoothness of the cured grout also tends to decrease.

The organic fibers include vinylon fibers, polypropylene fibers, polyethylene fibers, and aramid fibers. The organic fibers and carbon fibers preferably have a diameter of 0.005 to 1.0 mm and a length of 2 to 30 mm. The compounding amount of the organic fibers and / or carbon fibers is preferably an amount corresponding to less than 10% of the concrete volume after setting, and more preferably an amount corresponding to less than 7%. If the blending amount is 10% or more, the fiber dispersibility decreases,
In addition, the fluidity of the compound is liable to decrease, which is not preferable.

The composition constituting the grout material of the present invention has an average particle size of 3 from the viewpoint of increasing the filling density of the cured product.
Those containing an inorganic powder having an average particle size of 4 to 10 μm are more preferable. Quartz powder is particularly preferred as the inorganic powder because it is inexpensive in cost and hardly affects other properties. The quartz powder may be a powder containing silica as a main component in addition to quartz that is a natural mineral source. The compounding amount of the powder is preferably 50 parts by weight or less, more preferably 20 to 35 parts by weight, based on 100 parts by weight of cement. If the amount is more than 50 parts by weight, the fluidity of the compound decreases and the strength after curing decreases, which is not preferable.

In order to enhance the toughness after curing, the present composition preferably contains needle-like and / or plate-like particles having an average major axis diameter of 1 mm or less. Examples of the acicular particles include those composed of natural or synthetic ores such as wollastonite, bauxite, and mullite, and examples of the plate-like particles include mica flake, talc flake, vermiculite flake, and alumina flake. be able to. The amount of the acicular and / or plate-like particles is preferably at most 35 parts by weight, more preferably 10 to 25 parts by weight, based on 100 parts by weight of cement. The amount is 3
If the amount exceeds 5 parts by weight, the fluidity of the composition may be reduced or the curability may be reduced, which is not preferable. The shape and size of the acicular particles are preferably those having an acicularity, that is, a value of (major axis diameter / minor axis diameter) of 3 or more.

Further, in order to ensure the adhesion between the grout material and the structure, it is preferable to include an expanding material in the composition. The expansive material has a shrinkage reducing effect and may be any as long as it has a swelling action in a hydration reaction.For example, calcium sulfaluminate-based inorganic substances such as Irwin, lime-based inorganic substances such as calcium oxide, Examples thereof include various amorphous or crystalline aluminates, and metal powders such as metal aluminum powder and iron powder. The content of the expansive material varies depending on the type of expansive material used, but all may be in the range used in known ordinary cement grout materials. For example, in the case of using metallic aluminum powder, the binder material 1
0.0002 to 0.01 parts by weight, preferably 0.0006 to 0.008 parts by weight, per 100 parts by weight.

The grout material for the flowable grout pad method of the present invention may optionally contain components other than those described above, for example, an admixture such as a thickener, if necessary.

In manufacturing the grout material for the flowable grout pad method of the present invention, the order of blending each component is not particularly limited. The kneading of the compound may be carried out by using any kneading machine generally used in concrete production, for example, using an oscillating mixer, a pan-type mixer, a biaxial kneading mixer, a tilting mixer and the like. be able to. Also,
The method of filling the kneaded material into the mold may be such that the kneaded material is poured so as to fill the upper end of the mold. The shape and dimensions of the mold that can be filled are not limited. After filling, curing is carried out at normal temperature and pressure for about 3 to 4 weeks, whereby a strong grout pad material can be obtained.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd.), silica fume having an average particle size of 0.7 μm, mixed sand consisting of silica sand Nos. 4 and 5 in a weight ratio of 2: 1, diameter of 0.
05 mm steel fiber with a length of 3 mm, a commercially available polycarboxylic acid-based high-performance AE water reducing agent, natural quartz powder having an average particle size of 7 μm,
Acicular wollastonite having a major axis diameter of 0.3 mm and a major axis diameter / minor axis diameter of about 4, a calcium oxide-based expanding material (trade name: EXPAND, manufactured by Taiheiyo Cement Co., Ltd.), metal aluminum powder (purity ≧ 99) %, Fineness ≧ 180 mesh), a material selected from a methylcellulose-based thickener (manufactured by Shin-Etsu Chemical Co., Ltd.) and water are put into a twin-screw kneading mixer so that the compounding amounts shown in Table 1 are obtained, and kneading is performed. went.

[0022]

[Table 1]

The filling property of the kneaded material is determined by JSCE-
F531 “PC grout test method”
The 4 mm J funnel passage time was measured and evaluated, and the separation resistance at the time of filling was evaluated by measuring the breathing rate according to JSCE-F532 "PC grout test method" of JSCE. In addition, the compression strength and bending strength after curing are determined by JI
It was measured by a method according to SR5201. Further, the shrinkage property was evaluated by measuring the expansion rate up to a material age of 24 hours according to JSCE-F533 of the Japan Society of Civil Engineers “PC grout test method”. The results of each evaluation are also shown in Table 2.

[0024]

[Table 2]

[0025]

The grout material for the flowable grout pad method according to the present invention has a filling property and a non-shrinkage property equal to or higher than those of the conventional grout material, while providing a great improvement in strength and toughness. And has excellent shape retention characteristics. As a result, by using the present grout material, a grout pad having high strength, high toughness and extremely high shape accuracy can be easily obtained, and can be used for applications requiring high quality and high limit characteristics.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C04B 20:00 C04B 20:00 B 14:48 14:48 D 22:06 22:06 A 14:38 14 : 38 A 22:06 22:06 Z 22:04 22:04 24:26) 24:26) E 103: 32 103: 32

Claims (8)

[Claims] 1. A grout material for a flowable grout pad method, which comprises at least a compound containing cement, fine pozzolanic powder, aggregate having a particle size of 2 mm or less, water, and a water reducing agent. 2. The grout material for a flowable grout pad method according to claim 1, wherein the blend contains one or more of metal fibers, organic fibers and carbon fibers. 3. The metal fiber has a diameter of 0.01 to 1.0 mm,
The grout material according to claim 2, which is a steel fiber having a length of 2 to 5 mm. 4. The organic fiber has a diameter of 0.005 to 1.0 m.
The grout material for a flowable grout pad method according to claim 2, wherein the grout material is at least one fiber selected from vinylon fiber, polypropylene fiber, polyethylene fiber, and aramid fiber having a length of 2 to 30 mm. 5. The carbon fiber has a diameter of 0.005 to 1.0 m.
The grout material for a flowable grout pad method according to claim 2, which has a length of 2 to 30 mm. 6. The grout material for a flowable grout pad method according to claim 1, wherein the composition contains an inorganic powder having an average particle size of 3 to 20 μm. 7. The grout material for a flowable grout pad method according to claim 1, wherein the composition contains needle-like particles and / or plate-like particles having an average particle size of 1 mm or less. 8. The grout material for a flowable grout pad method according to claim 1, wherein the composition contains an expanding material.