JPH0718222B2 - Surface treatment method such as concrete - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for smoothing a solidified surface of concrete, cement mortar or the like.

(Prior art) In addition to concrete cast as a building frame, mortar coated on wall surfaces, etc., concrete and mortar construction members can be used with or without mold frame to remove the hardened surface. Immediately smooth and difficult to obtain, often results in recesses of various sizes.
This is due to residual bubbles on the contact surface of the form plate, due to the collection of dissolved fine air, bubbles due to water vaporization, gas generated by the solidification reaction of cement, sink marks during hardening of concrete, etc. Though considered, it is almost inevitable.

In addition, cracks may occur in aged concrete or concrete with an excessive amount of mixing water for molding.

Therefore, not only when concrete, cement mortar, etc. are used without coating, but also when surface coating is used, it is originally necessary to fill only the voids of these recesses or cracks with a filler and repair. That's fine.

Conventionally, as a method for filling a large number of these recesses or cracks, fluidized concrete, cement mortar, etc. have been used once or a plurality of times around the entire solidified surface of concrete or around the recesses, etc. A method has been adopted in which the excess filling material is scraped off while being painted with a slight pressure and filling and leveling with a roller, trowel, spatula, or the like.

(Problems to be solved by the invention) However, these conventional methods have a problem that the filling material is applied to even the unnecessary portion of the filling, and in addition to that, the solidified surface shape of the original concrete, etc. It often changes the color and the like, which is not preferable. The present inventor focused on the above problems and tried to solve them.

(Means for Solving Problems) As a result of earnest research on a conventional solution to the problems, the present inventor has a film-forming property only when it exists in contact with a solidified surface of concrete or the like, and has a solidified surface. The present invention has been completed by finding that the film breaks in the state of being lifted from the above, and that a portion to be filled is not formed when a coating material having no film-forming property and a surface tension adjusted is used. That is,
The gist of the present invention is, in a method of filling uncured concrete, cement mortar, gypsum plaster, etc. in a concave portion or a crack portion generated in a solidified surface of concrete or cement mortar, along the solidified surface, a portion in contact with the surface Although it has a film-forming property, at a concave hole or a crack portion, a coating material whose surface tension is adjusted so that it does not have a film-forming property at least in the opening portion of the large width is applied,
After forming a coating film leaving the opening of at least the wide portion of the concave hole or crack portion, uncured concrete on the coating film surface around the portion where the coating film is not formed , A cement mortar, gypsum plaster, etc., and then the surface of the concrete or cement mortar is removed by peeling off the entire coating film.

The details of the present invention will be described below.

As the coating material used in the present invention, a coating material having a film forming property such that it is dried when applied along the solidified surface of concrete or cement mortar or a coating film is formed by water absorption (liquid absorption) of concrete or the like is used. In addition, it must be possible to change the surface tension of the surface to be coated on the solidified surface of concrete or cement mortar by various methods. Originally, the film-forming property depends on various factors, but one of the major factors for the presence or absence of the film-forming property when applied to the solidified surface is whether it is weaker than the surface tension of the solidified surface. To be If it is weak, it spreads, and it has film-forming properties, but if it is strong, it is difficult to spread and it is difficult to form a film.

On the other hand, the solidified surface of cement mortar or the like adheres to the coating material and supports the coating surface, so it is difficult to break once it is formed, but in the concave holes or cracks on the solidified surface, the coating work is performed on the solidified surface. If applied slidably along or on the solidified surface, the paint will inevitably have an air layer between the concrete and the cement mortar solidified surface. Even if a thin film is instantaneously formed depending on the type of paint,
Since there is no support that can be adhered as described above, it is in an unstable state and is easily broken. This is easily achieved by using a paint that has been treated to increase the surface tension. When the concave hole has a circular shape, the diameter of the rupture film is elongated, and in the case of a crack, the larger the width thereof is, the easier the rupture occurs.

In the present invention, as long as the recessed hole to be filled, the diameter of the crack, and the minimum portion of the width have no film-forming property, the large portion naturally has no film-forming property. It suffices if the surface tension is large, but this causes a slight difference from the surface tension with respect to a portion having no recesses or the like, and if the adjustment is erroneous, the film-forming property on the entire surface may be lost. Therefore, for the adjustment, at least a portion having a large diameter or width is ruptured, that is, a film is not formed.
Repeating with a narrow width has certainty in adjusting the surface tension. Needless to say, the present invention is not limited to this repeating method, and includes the above-described method performed once.

As the paint having variable surface tension and film-forming property used in the present invention, all usual coating paints can be used. For example, emulsion type (polyvinyl acetate, ethylene-vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, methacrylic acid ester or acrylic acid ester-styrene copolymer, etc.), latex type (SBR, NBR, PV
dC), solution type (saponified ethylene-vinyl acetate copolymer, polyvinyl alcohol, acrylic ester-based or methacrylic acid ester-based copolymer, cellulose acetate, etc.) and the like.

As a method of changing the surface tension, adjustment of the paint concentration (usually increases if thinner), change in size of emulsion particles (usually increases when smaller) Temperature change (temperature of coated surface and paint) The higher the temperature, the lower the temperature will usually be.), The more surfactant added (the lower the amount, the more the film becomes weaker), the antifoaming agent added (silicone solution or emulsion added). Increases the surface tension).

These adjustments include various situations such as whether the solidified surface is concrete type or cement mortar type, whether the coated surface is in a dry state, the diameter and width of the recesses and cracks, what kind of paint is used, etc. It is the one that is selected according to the judgment of the product, but the most typical is the change in the concentration of the paint.
And used in an amount of about 20 to 50% by weight. The undiluted solution can be used as it is.

Since the coating film formed by using the above paint will be peeled off later as described later, it is necessary to have a certain tensile strength and tear strength, and a coating film thickness of usually 10 to 100 μm, preferably 30 to 60 μm is required. .

If these paints are applied to the inner surface of the concave hole or the inner wall surface of the crack, the object of the present invention cannot be achieved. That is, the method of the present invention is a method of filling the filler only in the portion where the coating film is not formed.

As a method of applying such a paint, it is not good to use a method such as spraying at a right angle or an angle close to the solidified surface of concrete or cement mortar. A coating method that does not follow the solidified surface, that is, does not follow the concave holes or crack inner wall surfaces of the solidified surface is required. Usually, roll coating, short brushed brush coating, ironing with a trowel are the simplest and most efficient. .

The paint usually forms a film if left for 1 to 24 hours. When the coating film is thin or a continuous coating film is not formed, this operation may be repeated 2-3 times as necessary.

Through the above operation, uncured concrete, cement mortar, plaster plaster, etc. are attached to the upper surface of the coating film around the opening that can be seen only on the inner surface of the recess and the inner wall of the crack without forming a film Etc. In addition to this, cement paste containing a synthetic resin emulsion, polymer mortar, etc. are used as the material to be filled.

After the application and filling, it is preferable to scrape off the bulged extra portion of the filling material with a spatula or the like, if necessary. If the filler is left immediately or for a while and the coating film formed before or after the filler is cured is peeled off,
It is possible to obtain a state in which the desired filler is applied only to the concave holes or cracks. Although the filled portion can be made considerably smooth depending on the filling operation, it becomes smoother by the scraping operation described above. However, the coating film is thick and may be slightly raised. After removing the coating film, this portion is smoothed again if necessary.

Incidentally, as described above, among the small concave holes and cracks that were not filled, that is, those that could not be filled because they were covered with the coating film, using a paint whose surface tension was adjusted to a higher level It is applied to the peripheral portion, and the same process is repeated to fill and smooth all desired recesses and cracks.

Hereinafter, description will be made with reference to examples.

(Example) FIG. 1 shows the state of the solidified surface S after concrete 1 is molded by a mold molding method (not shown) and the mold plate is removed. The depth is about 0.5 to 5 mm and the diameter is 1 mm. There are a lot of recessed holes 2, 2, ... With a maximum width of about 5 mm (circular) and a maximum width of about 5 mm (elongate), which is not only unsightly in appearance but also has cracks 2A, which is a problem in strength.

FIG. 2 shows the solidified surface S of concrete 1 shown in FIG. 1 coated with an ethylene-acrylic acid ester copolymer emulsion paint (about 45% by weight) whose surface tension is adjusted, using a roller having a hair length of about 3 mm. , Shows the surface condition after solidification,
The coating film 3 has concave holes 2, 2, ...
It is not formed in the opening of 2A, and coating films 3a, 3a ... are formed on these small concave holes and on the cracks 2a, 2a ..., and also on the areas where there are no concave holes or cracks. The film 3 is continuously formed with the coating films 3a, 3a .... That is, the larger the opening, the less the film is formed.

FIG. 3 corresponds to the cross-sectional view of FIG. 2, and there is no coating film 3 at the openings of the large-diameter concave holes 2, 2, ... On the solidified surface S of concrete. However, there are coating films 3a, 3a ... At the openings of the concave holes 2a, 2a ... With a small diameter or a small width, which are continuous with the coating films 3, 3 ...

FIG. 4 is a cross-sectional view showing a state in which the filling material 4, 4 ... Including the coating film-shaped recessed hole shown in FIG. In this stage, it is preferable that the raised filler is scraped off and smoothed as smoothly as possible along the surface of the coating film.

5 shows that the filler 4 is substantially flush with the solidified surface S after the coating films 3, 3 ..., 3a, 3a ... of FIG. 4 have been stripped off, but as shown in FIG. Repeating the scraping and leveling operations will make the surface even smoother. The recesses 2a, 2a ... With a small diameter or a small width remain open. To apply and fill the filler in these openings, use a paint with a surface tension of 20% by weight to increase the surface tension, and repeat the above operation to fill most of the concave holes and cracks. We were able to.

(Operation / Effect) The present invention utilizes the fact that the surface tension of the coating material can be easily changed to prevent the coating film from being formed in accordance with the shape and size of the concave holes and cracks. It has the advantage that it can be filled efficiently, and its utility value is extremely high.

[Brief description of drawings]

Fig. 1 shows the surface condition of concrete after mold forming.
The figure shows the surface state of a film-forming coating material whose surface tension has been adjusted and solidified. Fig. 3 shows the cross-sectional view of Fig. 2 and Fig. 4 shows the coating state of Fig. 3. Fig. 5 shows the state in which the filler is applied mainly to the part without the film, Fig. 5 shows the state after removing the coating film in Fig. 4, and Fig. 6 shows the entire state of the raised filler in Fig. 5 scraped off. Shows the state of being flush. Main ones of the reference numerals used in the drawings will be described. 2, 2 ... Recessed hole, recessed hole without coating film 2A ... Crack 2a, 2a ... Recessed hole with coating film 3 ... Coating film 3a, 3a ... Formed in opening of recessed hole, crack Coating film 4 ... Filler material S ... Concrete solidified surface

Claims (1)

[Claims] 1. A method of filling uncured concrete, cement mortar, gypsum plaster, etc. in a concave hole or a crack portion formed on a solidified surface of concrete or cement mortar, in a portion contacting the surface along the solidified surface. It has film-forming properties, but in the concave holes or cracks,
At least the opening of the large width portion is coated with a coating material whose surface tension is adjusted so as not to have film-forming property, and the opening portion of the concave hole or crack portion having at least the large width portion thereof is left uncoated. After forming a film, apply uncured concrete, cement mortar, plaster plaster, etc. to the surface of the coating film around the part where the coating film is not formed, and then peel off the entire coating film. Surface treatment method for concrete or cement mortar characterized by