JP2003335586A - Surface-roughening agent for concrete - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface-roughening agent which can easily form a rough surface within a short time by treating a cast surface after filling concrete, especially fluid concrete, a process for forming a rough surface on the concrete using this and a hardened product of the concrete having the rough surface formed through this process. <P>SOLUTION: The surface-roughening agent for the concrete comprises an accelerator (A) and a surfactant (B) having a surface tension of ≤50 dyn/cm. Here, a flow value of a cement paste containing the accelerator (A) is ≤80% of that of the one not containing this. The surface-roughening agent is used in the rough surface-forming process. The hardened product has the rough surface formed through this process. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to concrete, particularly a rough surface forming agent suitable for roughening a surface formed of concrete having fluidity, concrete using the rough surface forming agent, and particularly concrete having fluidity. The present invention relates to a method for forming a rough surface on a surface formed in step 1 and a hardened concrete body having a rough surface formed by the method for forming a rough surface.

[0002]

2. Description of the Related Art After filling concrete in a formwork or laying it for road paving, it is sometimes required to finish a concrete surface which comes into contact with outside air (hereinafter referred to as a casting surface) to a rough surface. Such a rough surface usually means a minute unevenness formed by using a combing tool such as a rake, a bamboo broom, an earth broom, a deck brush, a wire, or an embossing tool provided with unevenness.

[0003] For example, in the case of a large girder product, the placing surface of one girder product may be used by being joined to the placing surface of another girder product. In this case, when mortar or the like is filled between both casting surfaces and joined, it is considered that the adhesiveness between the casting surface and the mortar is better when both casting surfaces have fine irregularities.

As another example, on a concrete paved road, fine unevenness may be applied to the surface to prevent slippage. In such a case, if the placing surface is not horizontal and is a slope, even if fine asperities are made with a comb puller immediately after filling the concrete, the asperities will not be fixed because the concrete is still soft and the placing surface will not be fixed. It was difficult to finish the rough surface.

Concrete vibrating products typified by box culverts and girders are conventionally manufactured by filling so-called stiff concrete (hereinafter, stiff concrete), which has little fluidity, into a mold while applying strong vibration. However, it has been a serious problem that it is difficult to fill a formwork having a dense bar arrangement and that noise generated by a vibrator has a bad influence on the living environment.

As a new technology capable of effectively solving these problems, in recent years, a production in which concrete having large fluidity immediately after kneading (hereinafter, fluid concrete) such as so-called medium fluid concrete and high fluid concrete (hereinafter referred to as fluid concrete) is filled by microvibration. Methods are becoming popular.

The flowable concrete is not only able to solve the above-mentioned problems, but can be solved not only because the concrete is filled in the formwork while applying a slight vibration or when the flowability is extremely large, without applying any vibration. Has a great advantage in that it is finished smoothly and the conventional hardened concrete requires a lot of labor to finish the smoothing of the part by trowel finishing in a short time, or no trowel finishing is required at all. .

However, when the flowable concrete is used, even if minute irregularities are made with a comb puller immediately after filling the concrete, the concrete is not fixed because the concrete irregularities are not fixed, and a rough surface is formed after the concrete is hardened. Can not do it. Therefore, in the case of a large scale, such as a girder, which requires the finishing surface to be rough after curing, from the viewpoint of filling efficiency, it is preferable to use fluidized concrete, There is a problem that fluid concrete cannot be used because a rough surface cannot be formed.

[0009] In order to solve such a problem, it was possible to form a rough surface by leaving the concrete for a long time until the fluidity of the concrete is sufficiently lowered, but the concrete manufacturing process is significantly delayed. The evil could not be avoided.

Further, as a conventional method for roughening a cast surface, Japanese Patent Laid-Open No. 58-25912 discloses that a granular material is sprinkled on the surface of a concrete slurry, and then a roller-like pressure member is applied to the surface. It is disclosed that the surface is exposed by bringing it into contact with the surface of the surface and fixing the particles to the surface, and then pressing by a second roller-shaped pressing member to pattern the surface.

However, in the above-mentioned technique, since the aggregate is used for the powder and granules, the spraying work is complicated, and it is desirable to spray the slurry immediately after the surface of the slurry starts to be condensed.
Waiting for the setting of fluidized concrete to start such a setting also significantly delays the working time of concrete production.

The conventional surface treatment technology for concrete that does not harden (Japanese Patent Laid-Open No. 56-160358, etc.) aims at smoothing the concrete surface to be treated, and The agent used is designed to work in a dynamic concrete condition including slag during centrifugal molding, and a technique for finishing a concrete surface under a static condition after concrete filling is disclosed. Absent.

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to provide a rough surface forming agent capable of easily forming a rough surface in a short time by treating a concrete, particularly a casting surface after filling with fluid concrete, and the rough surface forming. It is to provide a concrete rough surface forming method using an agent and a concrete hardened body having a rough surface formed by the rough surface forming method.

[0014]

Means for Solving the Problems The gist of the present invention is to provide [1] an instantaneous binder (A) having the following characteristic i and a surfactant (B) having a surface tension of 50 dyn / cm or less. [Characteristic i: The paste flow value of the cement paste containing the instantaneous binder is 80% or less of the paste flow value of the cement paste containing no instantaneous binder. [2] A method for forming a rough surface of concrete using the rough surface forming agent described in [1] above, and [3] a concrete hardened body having a rough surface formed by the method for forming a rough surface described in [2] above. .

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION In order to fix minute irregularities formed by a comb puller for a long time immediately after filling concrete, in particular fluid concrete, the fluidity of concrete near the surface of the placing surface is kept in a short time. It is necessary to lower the amount in advance, and it is effective to apply an agent (hereinafter referred to as an instantaneous binder) capable of imparting an action to the concrete near the surface of the cast surface.

Since the action of the instant binder is essentially considered to result in increasing the yield value of the cement paste in concrete, the instant binder (A) according to the present invention is as follows. It is necessary to have the property i of [Characteristic i: The paste flow value of the cement paste containing the instantaneous binder is 80% or less of the paste flow value of the cement paste containing no instantaneous binder. ]

Here, the paste flow value is measured under the following conditions. Cement paste containing the instantaneous binder is a specific formulation II, cement paste containing no instantaneous binder,
Each has a specific formulation I. The specific formulation II consists of the weight of cement (C) shown in Table 1, tap water (W) and the instant binder, and the specific formulation I consists of the weight of cement shown in Table 1 and water. The instant binder is added to tap water immediately before kneading the cement paste with mortar to prepare an aqueous solution or an aqueous emulsion in advance, which is used as kneading water.

[0018]

[Table 1]

Each material according to the specific formulation I stored at room temperature 20 ° C for one day was kneaded at room temperature of 20 ° C with a mortar mixer (JISR5201.8.1 (2)) for 2 minutes at a low speed, and a flow table (JISR5201.10.1 ( 5)) Fill the above cement paste container (JIS R5201.8.1 (1)) without any gaps, scrape off the top, and gently pull out the cement paste container upward. Measure the maximum diameter at the position where the spread of cement paste flowing out from the cement paste container after the flow stops and the maximum diameter at the orthogonal position, and the average value of both diameters is the cement paste containing no instantaneous binder. And the paste flow value of. The paste flow value is measured within 5 minutes after the cement is contacted with water.

The paste flow value of the cement paste containing the instantaneous binder is the specific composition II stored at room temperature 20 ° C. for one day.
At room temperature of 20 ℃, kneading each material for 2 minutes with a mortar mixer (JISR5201.8.1 (2)) at a low speed, and a cement paste container (JISR5201.8.1 (JISR5201.8.1 (5)) on a flow table (JISR5201.10.1 (5)). 1)) is filled without any gaps, the top is scraped off, and the cement paste container is gently pulled out upward. The diameter of the cement paste that flows out from the cement paste container after the flow stops is the maximum, and the maximum diameter at the orthogonal position is measured, and the average value of both diameters is the cement paste containing the instantaneous binder. And the paste flow value of. The paste flow value is measured within 5 minutes after the cement is contacted with water.

For the rough surface forming property, the paste flow value of the cement paste containing the instantaneous binder is compared with the paste flow value of the cement paste containing no instantaneous binder.
80% or less, preferably 70% or less,
It is more preferably 60% or less. In the present invention, the paste flow value of the cement paste containing the instantaneous binder as described above is lower than the paste flow value of the cement paste containing no instantaneous binder,
This means that if the instant binder comes into contact with the unhardened concrete, the yield value of the cement paste in the concrete is increased to make it difficult for the shape to disappear when the concrete part is given a fine shape.

The instant binder (A) having the above characteristic i preferably further satisfies the following requirements. (1) Water-soluble low molecular weight compound: The instant binder (A) is a water-soluble compound from the viewpoint of easy use in the form of an aqueous solution that can be evenly applied to concrete on the surface of a cast surface. preferable. The water-soluble compound, at room temperature, in the state of forming a single molecule or a structure such as aggregates, micelles, liquid crystals, or a mixture thereof in water,
It is a compound that does not cause phase separation with water. A phase is a region having a macroscopic size and in which statistical physical quantities such as temperature and pressure are clearly defined (colloid chemistry, Volume 1, First Edition,
89-90, issued October 12, 1995, Tokyo Kagaku Dojin). Further, in the present invention, the water-soluble compound may include a stable aqueous emulsion.

Further, in the case of a water-soluble compound having a large molecular weight,
Since the viscosity of the aqueous solution may increase and workability may be impaired, the instantaneous binder (A) has a molecular weight of 20,000 or less, preferably 10,000 or less, more preferably 1,000 or less,
Most preferably, it has a low molecular weight of 500 or less.

(2) Being an inorganic compound: The instant binder (A) has a good rough surface-forming property.
It is preferably an inorganic compound.

Examples of the instantaneous binder (A) having such characteristics include polyaluminum chloride, aluminum sulfate, sodium aluminate, water glass, colloidal silica and the like. When used in combination with the surfactant (B) described later. In consideration of the above effect, a material containing at least one selected from aluminum sulfate and colloidal silica is preferable because it is particularly excellent in rough surface formability. These instant binders (A) may be used alone or in combination of two or more kinds.

On the other hand, when only the instantaneous binder (A) is applied to the casting surface, the concrete in the vicinity of the surface of the casting surface becomes harder due to lower fluidity, and fine irregularities can be imparted with a comb puller or the like. Although it becomes possible, there is an adverse effect such as concrete being clogged in the gap between the comb pulling tools when the minute unevenness is imparted, which may hinder the rough surface forming work. It is considered that this is because the application of the instantaneous binder (A) increases the yield value of the concrete as well as the plastic viscosity of the concrete.

Therefore, it is necessary to avoid that the plastic viscosity of the concrete becomes excessively large even if the yield value of the concrete increases due to the application of the instantaneous binder.

The inventors of the present invention have studied various methods of reducing the plastic viscosity without significantly impairing the ability of the instantaneous binder to increase the yield value of concrete, and as a result, the instantaneous binder (A) according to the present invention.
By using together with a surfactant having a surface tension of 50 dyn / cm or less (hereinafter, surfactant (B)), it is possible to easily and efficiently form fine irregularities by a combing tool or the like, and the desired effect is obtained. It was Here, the minute unevenness may be a shape in which each unevenness has a closed curve such as a polygon such as a triangle or a square, a circle or an ellipse, or a continuous or discontinuous streak shape. As for the size of irregularities, the maximum diameter of polygonal and closed curves is about 0.1 mm to 10 mm, the distance between individual irregularities is about 0.1 mm to 20 mm, and the streak width is 0.1 mm to 10 mm. Degree, muscle spacing 0.1 mm to 20
mm, with a streak depth of 0.1 mm to 10 mm distributed on the concrete part to be roughened according to the application.

The surface tension of the surfactant (B) is a value obtained by measuring an aqueous solution having a solid content concentration of 0.1% by weight at 20 ° C. by the Dunui surface tension measuring method (JIS K-2525). In this case, the surface tension of the surfactant (B) obtained under the above conditions is 50 dyn / cm or less and 45 dyn / cm.
cm or less is preferable, and 40 dyn / cm or less is more preferable.

The surfactant (B) may be any of anionic, nonionic, cationic and zwitterionic surfactants having surface tension lowering ability, but it depends on the interaction with the component (A). Anionic type and nonionic type that are less likely to aggregate or separate are preferable. Furthermore, an anionic activator which is excellent in lubricity for forming fine irregularities such as combing is preferable, and an alkyl sulfate ester salt or a (poly) oxyethylene alkyl sulfate ester salt is particularly preferable.

As the alkyl sulfate ester salt,
The monovalent metal salt, the ammonium salt, and the salt with amino alcohol which have a C8-C22 alkyl group are mentioned. For example, Emar 0 (trade name, Kao Corporation)
Manufactured) and the like. As the alkyl sulfate ester salt, a (poly) oxyethylene alkyl sulfate ester salt is more preferable from the viewpoint of water solubility, and in that case, the alkyl group is a chain having 10 to 14 carbon atoms, or a nonylphenol group. The number of ethylene oxide groups (hereinafter, also referred to as EO) is preferably 1 to 30, more preferably 1 to 5. For example, Emar 20C
(The same), Emar E-27C (the same), Emar D-3-
D (the same), Rebenol WX (the same) and the like.

The surfactant (B) preferably further has the following characteristic ii. [Characteristic ii: 1 of cement paste containing surfactant
The increase rate of the paste flow value after 0 times tapping is larger than the increase rate of the paste flow value after 10 times tapping of the cement paste containing no surfactant. ]

Here, the cement paste containing the surfactant has the specific formulation IV, and the cement paste containing no surfactant has the specific formulation III. Table 2 shows the specific formulations III and IV.

[0034]

[Table 2]

The characteristic ii is the same test method as the characteristic i. After measuring the paste flow value Pb III according to the specific composition III, the paste flow value Pa III after tapping 10 times in succession is measured. Pa III / Pb III) × 100 (%) is defined as the increase rate of the paste flow value. The increase rate of the paste flow value is similarly measured for the specific formulation IV. The paste flow value Pa is measured within 5 minutes after the cement is contacted with water. Further, the defoaming agent, the instant binder and the surfactant are added to tap water immediately before kneading the cement paste with a mortar to prepare an aqueous solution or an aqueous emulsion in advance, which is used as kneading water.

In this case, the specific formulation for the specific formulation III
Ratio of increase rate of IV paste flow value:

[0037]

[Equation 1]

Is preferably 102% or more, more preferably 105% or more.

More preferably, the paste flow of the cement paste containing the surfactant is 95 to 105 m.
The solid content in the kneading water of the surfactant (B) to be m is preferably 3.0% by weight or less, more preferably 2.0% by weight or less, further preferably 1.0% by weight in the specific formulation IV.
It is less than or equal to wt.

In the present invention, the fact that the increase rate of the paste flow value in the cement paste containing the surfactant is larger than the increase rate of the paste flow value in the cement paste containing no surfactant is instantaneous. This means that the action of the binder reduces the plastic viscosity of the cement paste in the concrete having an increased yield value, allows the rough surface to be formed by a light combing operation, and moreover the rough surface does not easily disappear by the weight of the concrete.

After the instantaneous binder (A) and the surfactant (B) according to the present invention are used together and applied to the casting surface, fine irregularities can be easily formed by a combing tool, etc. The unevenness does not disappear due to the weight of the concrete, and the excellent effect that the casting surface after hardening of the concrete can be finished to a rough surface is exhibited.

The rough surface forming agent according to the present invention is the instantaneous binder (A).
Immediately before casting, an aqueous solution or water-based emulsion containing water and a surface-active agent (B), or an aqueous solution or water-based emulsion containing the instantaneous binder (A) and the surface-active agent (B) individually Such as mixing, applying separately to the same casting surface,
It means a set of the instantaneous binding agent (A) and the surfactant (B) in the embodiment used at the same time.

Below, the instantaneous binder (A) and the surfactant (B)
A more preferred embodiment of the surface-roughening agent of the present invention which is used in combination with is described.

Since the instantaneous binding agent (A) and the surfactant (B) may be applied to the driving surface almost at the same time, they may be separately applied as an aqueous solution, and more preferably applied to the driving surface. Is to mix both of them and apply them as one liquid to the casting surface.

In these cases, the mixing ratio of the instantaneous binder (A) and the surfactant (B) is a solid content weight ratio and the instantaneous binder (A) /
Surfactant (B) = 100/1 to 100/10 is preferable, and 100/3 to 100/7 is more preferable.

When the amount of the surfactant (B) is 1 part by weight or more with respect to 100 parts by weight of the instantaneous binder (A), the fluidity of the concrete near the surface of the casting surface is improved, and the fineness due to embossing or combing is improved. Concavities and convexities are easily formed, and the surfactant (B) is the instantaneous binder (A).
Up to 10 parts by weight with respect to 100 parts by weight, the fluidity in the vicinity of the surface of the casting surface does not excessively increase, and it becomes easier to form fine irregularities due to combing and the like, and the fine irregularities once formed are less likely to disappear. Become.

When the instantaneous binder (A) and the surfactant (B) are used as an aqueous solution, the solid content concentration of the instantaneous binder (A) is preferably 1 to 40% by weight, and 5 to 30% by weight. weight%
Is more preferable, 10 to 20% by weight is most preferable, and the solid content concentration of the surfactant (B) is preferably 0.01 to 4% by weight, more preferably 0.05 to 3% by weight, and 0.1
~ 2 wt% is most preferred.

When the instantaneous binder (A) and the surfactant (B) are used as an aqueous solution, the total solid content concentration of the instantaneous binder (A) and the surfactant (B) is 1 -40% by weight is preferred, 5-30% by weight is more preferred, and 10-20% by weight is most preferred.

When the instantaneous binder (A) and the surfactant (B) are used in the form of an aqueous solution or when they are used as a one-component aqueous solution, the effects of the present invention are not impaired, Known additives may be added to the aqueous solution as needed. As an additive,
Examples thereof include a waterproofing agent, a rust preventive, a colorant, a fungicide, a crack reducing agent, a dye, and a pigment. These may be added alone or in combination of two or more kinds.

The rough surface forming agent having the above structure is
It has an effect that a rough surface can be easily formed in a short time by treating a concrete, particularly a cast surface after filling with fluid concrete.

Next, a preferred rough surface forming method using the rough surface forming agent of the present invention will be described. The rough surface forming agent of the present invention,
It is suitable for concrete with a slump of 5 cm or more, but it is more difficult to form a rough surface with a slump of 8 cm or more, and a slump of 18 cm or more, which is a fluidity concrete according to the present invention, is called so-called medium-flowing concrete.
It is suitable for forming a rough surface of high-fluidity concrete having a slump flow of 500 to 750 mm, a slump flow of 500 to 750 mm, which is called high-fluidity concrete, and a slump flow of 600 to 750 mm, which is said to be difficult to form a rough surface. In addition, the slump means the value of the slump obtained by the test described in JIS A1101, and the slump flow is obtained by the slump flow test method described in "High-fluidity Concrey construction guideline" (1st edition, Japan Society of Civil Engineers). The value of slump flow.

As an example, slump flow 500-75
A method for forming a rough surface of a vibrating product filled with 0 mm high fluidity concrete will be described in detail. The vibrating product is a standardized concrete product with a certain shape and size,
A form is filled with concrete and is formed by vibration compaction without centrifugal compaction or without vibration compaction.
Here, the vibration compaction means the vibration compaction described on page 374 of the Concrete Handbook (2nd edition, Japan Concrete Engineering Association), and the centrifugal compaction means the concrete handbook (second
Edition, edited by the Japan Concrete Engineering Association), page 695, and means centrifugal compaction.

After filling the mold with the high-fluidity concrete,
Within 30 minutes, preferably within 20 minutes, and more preferably within 15 minutes, the rough surface forming agent containing the instant binder (A) and the surfactant (B) according to the present invention is applied to the mold. Apply to the installation surface.

Since the instantaneous binder (A) and the surfactant (B) may be applied to the casting surface almost at the same time, they may be separately made into aqueous solutions and applied to the casting surface, and more preferably. Is to mix both of them and apply them as one liquid to the casting surface.

In this case, the rough surface forming agent may be applied to the driving surface with a brush or the like, but the method of spraying with a spraying machine is more efficient and more preferable. A commercially available sprayer can be used as the sprayer.

The amount of the surface roughening agent applied or sprayed is preferably 1 to 40 g, more preferably 4 to 25 g, and most preferably 8 to 20 g in terms of solid content per square meter of the concrete surface.

Within 30 minutes, preferably within 20 minutes, and more preferably within 10 minutes after applying or spraying the roughening agent on the casting surface, fine irregularities are formed on the casting surface with a comb tool, a rake or the like. Form.

The distance between the combs is preferably 0.1 to 20 m.
m, more preferably 0.5 to 15 mm, further preferably 0.5 to 10 mm. In this step, if the surface-roughening agent application portion is smoothed with a trowel or the like before the fine irregularities are formed, the fine irregularities can be more easily formed.

As described above, when the concrete having fine irregularities is cured and cured, it is possible to obtain a concrete hardened body having a finely rough surface for placing. Examples of the hardened concrete include hardened concrete such as concrete pavement for roads and box culverts,
Concrete products such as girders, piles, and fume tubes are mentioned, and vibrating products such as box culverts and girders manufactured by filling with fluidized concrete are preferable targets. In particular, in the case of a concrete product, if the product is subjected to steam curing after forming fine irregularities, a concrete product having a rough surface on the placing surface can be obtained in a short time.

[0060]

EXAMPLES Instant binders A1 to A5 used in this example, which satisfy the property i and are water-soluble low molecular weight compounds and inorganic compounds
Is shown in Table 3.

[0061]

[Table 3]

Table 4 shows the combinations of the instantaneous binder and the surfactant used in this example, and their applicability.

[0063]

[Table 4]

[Preparation of Concrete] Various materials were weighed so as to have the volumes shown in the high-fluidity concrete in Table 5, and the materials except the water mixed with the high-performance water reducing agent were put into a pan-type mixer for 10 seconds. After kneading, water mixed with a high-performance water reducing agent was added and kneading was continued for 2 minutes. Then, the kneaded product was discharged from the mixer, and the stamp flow of the obtained concrete was measured. In addition, the slump flow value immediately after discharge was measured according to "High-fluidity concrete construction guideline (civil engineering society edition)". The total amount of kneaded concrete was 30 kg.

[0065]

[Table 5]

Examples 1-5, 6-1-5, 7-1-3,
8-1 to 6 and 9-1 to 5 and Comparative Examples 1 to 3 Rough surface depth of the roughening agent obtained in each of Examples and Comparative Examples for the concrete obtained as described above, and rake operation The property was evaluated based on the following rough surface forming method. The results are shown in Table 6.

[Rough Surface Forming Method] (1) Concrete was put into a steel mold having a length of 50 cm, a width of 150 cm and a height of 30 cm to a height of 30 cm. (2) Commercially available spray (a product number: Dariya pressure type full-automatic spray DA-1) with a rough surface forming agent adjusted to a predetermined concentration on the casting surface.
0, made by Dariya). (3) 10 minutes after spraying, the rough surface forming agent sprayed portion was lightly conditioned with a trowel to make the surface smooth, and immediately the following work was performed. (4) The rough surface forming agent-sprayed portion was brushed with a rake having a comb interval of 3 mm to form fine irregularities (depth 5 mm), and rake operability was evaluated. The time required for brushing was about 10 seconds. (5) Next, after the brushing is finished, the mold is put at 20 ° C.
It was allowed to stand at room temperature for 1 minute, and further steam-cured at 65 ° C. for 4 hours. (6) After 30 minutes from the completion of steam curing, the mold was demolded, and the state of fine irregularities on the placing surface was observed to evaluate the rough surface depth.

The evaluation criteria of rake operability and rough surface depth are shown below. [Rake operability] ◎: Mortar does not easily adhere to the combs, and combing can be performed smoothly. ◯: If combing is performed slowly, it is difficult for mortar to adhere to the comb. X: Even if the combing is performed slowly, the workability is poor due to the attachment of moretaral to the comb.

[Rough Surface Depth (Average Depth)] ◎: 2.0 mm or more ○ to ◎: 1.0-2.0 mm ○: 0.5-1.0 mm ×: 0.5 mm or less In the present embodiment, rake operability and roughness are rough. If either of the evaluations of the surface depth is x, the product is rejected.

[0070]

[Table 6]

From the results shown in Table 6, the rough surface forming agents obtained in the respective examples are
It can be seen that the rake has excellent operability and has a large rough surface depth.

Example 10 Reinforcing bars were assembled in a mold, and the high-fluidity concrete and medium-fluidity concrete shown in Table 5 were poured into the mold, and a rough surface was formed on the casting surface by the rough surface forming method. . The specifications of the block products obtained are as follows.

Formwork: Concrete injection space is 10c in length
m, width 20 cm, height 50 cm steel mold. Reinforcing bar: As shown in FIG. 1, a reinforcing bar having a cross-sectional diameter of 5 mm was assembled in a grid pattern so that the center interval of the reinforcing bar was 5 cm. Each grid point (joint part) of the reinforcing bar was fixed with solder.

Measurement conditions for slump, etc .: After kneading concrete in the same manner as described above, immediately, slump and slump flow of concrete were measured.

Filling conditions: Concrete immediately after kneading was filled for 4 minutes until the inner wall of the mold was completely covered while applying vibration of 0.3 mm in amplitude and 1800 vpm in frequency to the mold.

A rough surface was formed on the cast surface under the same conditions as in Example 8-3, and the rake operability and the rough surface formation state after steam curing were observed. The results are shown below. Block products made of medium-flowing concrete: rough surface depth ◎,
Rake operability ○ Block products made of high-fluidity concrete: rough surface depth ◎,
Rake operability ◎

From these results, it is understood that by using the rough surface forming agent of the present invention, it is possible to obtain a concrete product in which minute rough surfaces are precisely formed even when using medium fluidity concrete or high fluidity concrete.

[0078]

By using the rough surface forming agent of the present invention, concrete, particularly the casting surface after filling with fluid concrete can be treated to easily form a rough surface in a short time.
The effect that a concrete hardened | cured body or a concrete product in which the minute rough surface was precisely formed can be obtained is produced.

[Brief description of drawings]

FIG. 1 is a schematic view of a reinforcing bar used in Example 10. The left figure is a schematic view of the reinforcing bar viewed from the vertical direction, the upper right figure is a schematic view of the reinforcing bar viewed from the height direction, and the lower right figure is a schematic view of the reinforcing bar viewed from the width direction.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Daisuke Shiba             1334 Minato Minato, Wakayama Kao Corporation             Within F-term (reference) 4G012 RB02                 4G055 AA01 AB00 BA87

Claims (7)

[Claims] 1. An instant binding agent (A) having the following characteristic i:
A roughening agent for concrete containing a surfactant (B) having a surface tension of 50 dyn / cm or less. [Characteristic i:
The paste flow value of the cement paste containing the instantaneous binder is 80% or less of the paste flow value of the cement paste containing no instantaneous binder. ] 2. The rough surface forming agent according to claim 1, which is used for fluid concrete. 3. The method according to claim 1, which is used for manufacturing a vibration product.
The rough surface forming agent described. 4. The instantaneous binder (A) is one or more selected from the group consisting of polyaluminum chloride, aluminum sulfate, sodium aluminate, water glass and colloidal silica. Roughening agent. 5. The surface-roughening agent according to claim 1, wherein the surfactant (B) is an anionic surfactant. 6. A method for forming a rough surface of concrete using the rough surface forming agent according to claim 1. 7. A hardened concrete body having a rough surface formed by the method for forming a rough surface according to claim 6.