JP2517175B2 - Lightweight concrete panel manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a lightweight concrete panel, particularly to a lightweight concrete panel containing lightweight aggregate.

[Background Art] Lightweight concrete panels include lightweight aggregate concrete panels and lightweight cellular concrete panels. Compared with lightweight cellular concrete panels, lightweight aggregate concrete panels have the advantage of being able to control the specific gravity and obtain large panels with thick inner and outer walls that are easy to control because they use lightweight aggregate. .

Such a lightweight aggregate concrete panel is manufactured by placing a lightweight concrete slurry containing lightweight aggregate (for example, perlite) in a molding frame.

[Problems to be Solved by the Invention] In manufacturing a conventional lightweight aggregate concrete panel,
In order to facilitate the pouring of the slurry into the mold, the viscosity of the slurry is lowered to improve the fluidity, and after the slurry is cast into the molding frame, it is a lightweight aggregate during the reaction hardening (solidification). Are floated on the surface, and the lightweight aggregate is exposed on the surface of the obtained panel, resulting in a poor appearance. Therefore, in order to conceal the lightweight aggregate on the surface, a thick finish coating of the coating film is required, which makes the work troublesome and fails to obtain a preferable design.

On the other hand, if the viscosity of the concrete slurry is increased in order to prevent such floating of the lightweight aggregate, the fluidity of the slurry deteriorates, making it difficult to pour it into the formwork.

It is an object of the present invention to provide a method for producing a lightweight concrete panel, which can maintain a good admixture of the lightweight aggregate in the concrete slurry during solidification.

[Means for Solving the Problems] A method for manufacturing a lightweight concrete panel according to the present invention is
After adding sodium carbonate or potassium carbonate as a condensation control agent to the concrete slurry containing lightweight aggregate, this Kunkrete slurry is placed in a molding form, and the reaction slurry is hardened while maintaining the concrete slurry at 25 to 35 ° C. It is characterized by

As the lightweight aggregate, artificial lightweight aggregate (plastic hollow body etc.), natural lightweight aggregate (perlite etc.) or by-product lightweight aggregate (coal scrap etc.) can be arbitrarily used.

The setting control agent is for adjusting the reaction rate of the slurry.

The amount of this coagulation control agent added was 0.01 in terms of the total powder ratio.
~ 0.25 wt% is preferred. If it is less than 0.01% by weight, the reaction cannot be controlled, and if it is more than 0.25% by weight, the cement reaction is hindered and sufficient strength cannot be exhibited.

If the temperature maintained during the reaction hardening of the concrete slurry is lower than 25 ° C., the cement particles settle and the aggregate easily floats. Further, when the temperature is higher than 35 ° C., the reactivity due to temperature becomes too strong,
The effect of adding a coagulation control agent disappears and commercialization becomes impossible.

In order to keep the concrete slurry in the above temperature range, for example, it can be carried out as follows.

The temperature of the kneading water is adjusted according to the temperature of the powder raw material.

The temperature of the apparatus and the atmosphere that come into contact with the slurry such as the mold are adjusted by the air conditioning means.

[Operation] Since a setting control agent is added to the concrete slurry containing the lightweight aggregate according to the present invention, and the temperature is kept within a predetermined range during the setting reaction, the fluidity of the slurry is increased. However, the reaction rate during solidification is adjusted so that the lightweight aggregate mixed in the slurry does not float to the surface side.

[Example] An example of a method for manufacturing a lightweight concrete panel according to the present invention will be described with reference to the drawings.

First, potassium carbonate, which is a setting control agent, is added to and mixed with a concrete slurry in which perlite is mixed as a lightweight aggregate.

Next, as shown in FIG. 1, the concrete slurry 11
The concrete slurry of this temperature is heated to 25-35 ℃.
11 is placed in the molding frame 12. During this casting, a coagulation control agent was added, and the temperature of the slurry 11 was 25-
Since it is maintained at 35 ° C, the slurry 11 has sufficient fluidity. The lightweight aggregate 13 is uniformly dispersed in the concrete slurry 11.

Next, as shown in FIG. 2, the concrete slurry 11
To solidify. During this solidification, the lightweight aggregate 13 does not float on the surface side, and the slurry 11 solidifies into the concrete 14 while being uniformly mixed in the slurry 11. Thus, the lightweight concrete panel 15 integrated with the inner and outer walls according to the present embodiment, in which the lightweight aggregate 13 is uniformly dispersed in the concrete 14, is obtained.

According to the above example, in the concrete slurry 11 containing the lightweight aggregate 13, a setting control agent is added, and during the setting reaction, the temperature is kept at 25 to 35 ° C.,
The reaction rate is adjusted so that the lightweight aggregate 13 mixed in the slurry does not float to the surface side. Therefore,
Since the panel 15 can be manufactured using the slurry 11 having high fluidity, it is useful for improving manufacturing efficiency.

In addition, as a result of being able to manufacture the lightweight concrete panel 15 in this way, the lightweight aggregate 13 of the conventional panel is upward because the lightweight aggregate 13 is uniformly dispersed in the concrete 14 of the obtained panel 15. Problems due to uneven distribution can be eliminated, and the performance of the panel 15 can be improved.

Although potassium carbonate was added to the slurry as a coagulation control agent in the above-mentioned examples, sodium carbonate can be added instead.

Further, in the above example, the lightweight aggregate 13 was uniformly dispersed in the concrete 14 of the panel 15, but by adjusting the type and addition amount of the coagulation control agent, sedimentation of the cement particles and the lightweight aggregate were performed. It is also possible to intentionally make the dispersed state of the lightweight aggregate 13 non-uniform by appropriately adjusting the degree of floating of the lightweight aggregate 13. That is, in this way, a panel in which a solid layer (having a large strength and a small heat insulating property), an intermediate layer and a low density layer (having a large insulating property and a small strength) are continuously formed can be obtained.

[Effects of the Invention] According to the method for manufacturing a lightweight concrete panel of the present invention, the lightweight aggregate in the concrete slurry can be kept in a good mixed state during solidification, and as a result, a panel having good performance can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing a method for manufacturing a lightweight concrete panel according to an embodiment of the present invention, and FIG. 2 is a sectional view of a panel obtained by this embodiment. 11 …… Concrete slurry, 12 …… Formwork, 13 …… Lightweight aggregate, 14 …… Concrete, 15 …… Lightweight concrete panel.

Claims (1)

(57) [Claims] 1. After adding sodium carbonate or potassium carbonate as a setting control agent to a concrete slurry containing lightweight aggregate, the Kunkrete slurry is cast into a molding frame to prepare the concrete slurry at 25 to 35 ° C. A method for producing a lightweight concrete panel, which is characterized by carrying out a reaction hardening while maintaining the above.