JPS609708A - Method of mixing and injecting light aerated concrete slurry - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Conventionally, in the production of lightweight cellular concrete, a slurry of lightweight cellular concrete raw materials, such as silicic raw materials, calcareous raw materials, other binders, and water, is stirred with a mixer,
The mixture is made into a slurry, which is poured into the formwork. However, when stirring with a mixer, air bubbles are mixed in and carried into the mold as they are, resulting in the formation of coarse cavities on the surface and inside of the product, deteriorating its appearance.

The present invention has been made to solve such problems, and is designed to eliminate air bubbles that are mixed in when stirring with a mixer.
In the mixer, the slurry is generally stirred and mixed by the mixer, then vibration is applied after the stirring is stopped, and while the slurry is being poured from the mixer into the formwork.
It is most preferable to continue applying vibrational acceleration, but it is also possible to apply it during stirring.

The vibration acceleration is preferably applied by a biscillator, and the insertion method should be determined in relation to the mixer equipment, but in the case of a vertical method as shown in Figure 1, the range of influence will be wider. Therefore, stirring blade 40
It is preferable to insert the rod-shaped vibrator 3, for example, through the support tube 1 and the reinforcing joint 2, closer to the middle between the center of the mixer and the wall surface, and slightly away from the bottom surface of the mixer, within a range that does not impede rotational movement. Further, in order to uniformly defoam the air bubbles within the mixer, it is preferable to insert the air bubbles at equal intervals in the circumferential direction.

The outstanding feature of "Honmei W" is that the equipment that applies vibration acceleration is built into the mixer, so no new processes are required, and the equipment itself is simple. Since there is no need to move up and down, durability is greatly improved.Secondly, since the vibration acceleration is maintained before the blowing agent reaction starts, the air bubbles generated by the blowing agent are completely eliminated. It must not be destroyed.

Thirdly, it is possible to significantly reduce the air bubble inclusion coefficient, particularly the harmful air bubbles of 6Xφ or more.

Next, the present invention will be specifically explained. The slurry used was
To 100 parts of a mixture of 60 parts of crushed silica, 10 parts of quicklime, and 60 parts of ordinary Portland cement, 70 parts of water was added, and a blowing agent was added to the solid material, each part by weight.
0.07 part was added.

In addition, the vibrator 3 used has a vibration frequency of 12000.
times/minute, amplitude 2 x 10-3 m%, vibration acceleration 5G (actually measured value).

These raw materials are 80cm in diameter using conventional manufacturing methods.
rn, height of 70 cIn, and mixed for 3 minutes at a rotation speed of 65 rpm. This was then injected into the mold from near the bottom of the mold over a period of about 3 minutes through a pipe located at the bottom of the mixer. One was left as it was without vibration, and the other was vibrated for 30 seconds with a vibrator inserted after the injection was completed. Furthermore, in the manufacturing method of the present invention, after the mixing is completed, stirring is stopped, and the slurry is subjected to vibration acceleration using a vibrator for 15 seconds. It was cut, the diameter and number of air bubbles were measured, and the air bubble inclusion coefficient was calculated.

This air bubble mixing amount coefficient means that the air bubble diameter is 2X or more and 3
It is classified into less than It shows the degree of the amount of air bubbles mixed in, and the larger the amount of air bubbles mixed in, the higher the value.

=6 - When the manufacturing method of the present invention is used, the air bubble mixing amount coefficient is ff!, as shown in Table 1. It was confirmed that it was 690 per 2, which was significantly reduced compared to 1360 when no vibration was applied.

In addition, compared to the case where vibration was applied after pouring into the mold, it was confirmed that although the number of bubbles of 2 to 6X increased slightly, bubbles of 6% or more could be completely prevented. was 650% of the predetermined value, and there was no difference from the case where no vibration was applied.

Table 1 Conventionally, a four-way method for applying vibrational acceleration to the slurry after injection has been known, but due to a difference in the timing of vibration, etc., the bubbles generated by the foaming agent are destroyed.
Although there was a drawback that the foaming height was low, the present invention not only provides a defoaming effect, but also provides vibration before the foaming agent starts foaming, making it possible to destroy the bubbles generated by the foaming agent. It is characterized by high utilization efficiency of the blowing agent.

EXAMPLE Using the mixer shown in FIG. 1, the following materials were mixed: 45 parts by weight of crushed silica, 6 parts of quicklime, 27 itl [>100 parts of mixture,
70 parts of water was added to 20 parts of the collection site and 2 parts of gypsum, and 0.07 parts of a foaming agent was added to the solid material. The vibration acceleration is applied after the slurry excluding the foaming agent is poured, stirred at a speed of 160 rpm for 2 minutes and 60 seconds, then the foaming agent is immediately added, stirred for 60 seconds, and then the formwork (1
, 5m width x 6. At the end of injection 1, vibration acceleration was applied for about 6 minutes while injecting the sample into the tube (0.0 m length x 0.7 m height).

The injection method was such that the slurry was transferred from the bottom of the mixer 5 through the injection pipe 6 to near the bottom of the mold 7, as shown in FIG. Then, when the air bubble inclusion coefficient of the product after curing was calculated for the center part in the width direction, it was found to be 1
m'' p510 and p1 1 when no vibration acceleration is applied
Although it was significantly reduced compared to 000 to 1200 and slightly increased compared to 60 to 200 when vibration was applied after injection, it was confirmed that there is an effect of reducing the air bubble inclusion coefficient. Further, when comparing the amount of air bubbles mixed in at 3X or more, in this method, it is 0, which is the same as when vibration is applied after injection, and it is significantly reduced compared to 500 to 700 when vibration is not applied. Further, the foaming height remained unchanged at 650% of that when no vibration was applied.

[Brief explanation of the drawing]

FIG. 1 is a schematic side sectional view of the mixer, and FIG. 2 is a schematic side view showing the arrangement of the mixer and formwork. 1 ・Support pipe 2 Reinforcement joint 3 Rod-shaped pie break 4 Stirring blade 5 Mixer 6 Injection pipe 7 Formwork patent applicant Asahi Kasei Corporation

Claims (1)

[Claims] A method for mixing and pouring a light-covered cellular concrete slurry, which is characterized by applying vibration acceleration to the lightweight cellular concrete raw material slurry in a mixer using a biscillator installed in the mixer.