JPH01157805A - Colored composite concrete pole - Google Patents

Abstract

PURPOSE:To manufacture a colored concrete pole of uniform tone, good strength and low cost by injecting color mortar into a frame, molding a color mortar outer shell of given thick wall by means of a centrifugal molding, injecting regular concrete into the outer shell and centrifugal molding again. CONSTITUTION:A reinforced squirrel cage 2 is disposed in a lower molding frame of a molding frame 1 divided into upper and lower section, and a PC steel material 3 is tensed temporarily, and then the color mortar is put into the molding frame 1, the upper and lower frames being connected together, and the PC steel 3 is formerly tensed. A color mortar layer 4 as an outer shell is formed on the inner peripheral surface of the molding frame 1 by revolving the molding frame 1 at high speed. Ordinary concrete is injected inside the color mortar layer 4 before the color mortar layer 4 is cured, and a hollow concrete main body 5 is formed by centrifugal force, subjected to steam-curing and imparted with specified strength. The proper thickness of the color mortar layer 4 is 5-10mm which distributes the color all over to provide a uniform tone, and the material cost never becomes high.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a colored composite concrete pole, and in particular, it relates to a colored composite concrete pole, and in particular, to a colored composite pole in the molding of a concrete pole by centrifugal force molding. It concerns forming colored composite concrete poles.

[Prior Art] In areas where it is important to maintain a good landscape, such as parks and green areas, concrete poles whose surface layer is colored green, for example, may be used.

As this coloring means, there are methods that apply color paint, methods that mix pigments into the entire amount of concrete during concrete pole molding, and methods that use colored cement as cement.

[Problems to be solved by the invention] However, the former method increases the labor cost for painting and is difficult to put into practical use, and the latter method, in which a pigment is mixed, cannot achieve the desired color if the amount mixed is small. When mixing a large amount, the strength of the concrete decreases, and it is difficult to sufficiently mix the total amount of concrete, making it difficult to achieve a uniform color over the entire surface layer, and even between balls. The drawback is that the colors are different.

Furthermore, in the case of molding with colored cement, the cement unit price is about 10 times or more compared to ordinary cement, making it extremely expensive and uneconomical.

Therefore, a technical problem arises that needs to be solved in order to produce a colored concrete pole that is uniform in color, has high strength, and is inexpensive.The present invention aims to solve this problem. purpose.

[Means for Solving the Problems] The present invention was proposed to achieve the above object, and in forming concrete poles by centrifugal force forming, colored mortar is injected into the formwork. A colored composite concrete pole characterized in that a thin colored mortar shell of 5 to 10 mm is formed by centrifugal force forming, ordinary concrete is poured into this outer shell, and the structure is formed by centrifugal force forming again. We aim to provide the following.

[Operation] When performing centrifugal compaction of concrete poles, the present invention first injects colored mortar into a form and performs centrifugal force molding to form a colored outer shell.

Moreover, since this outer shell is approximately 5 to 10 mm, the material cost of the colored mortar can be reduced as much as possible, and the strength of the outer shell can be maintained sufficiently. Furthermore, ordinary concrete is injected into this outer shell and centrifugal force forming is performed again to form the concrete pole, so the outer shell and the ordinary concrete inside work together to maintain the specified strength as a concrete pole. Therefore, it is possible to obtain uniformly colored concrete poles while reducing costs.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the accompanying drawings. In Figure 1, the molding frame is divided into upper and lower parts (1)
Place the reinforcing bar cage (2) in the lower formwork and temporarily tension the prestressed steel (3), then put color mortar into the forming formwork (+) and cover the upper formwork with the lower formwork. Then, connect the upper and lower formwork to each other and fully tension the PC steel material (3).

Next, the molding frame (1) is rotated at high speed to form a colored mortar layer (4) as an outer shell on the inner peripheral surface of the molding frame (1) by centrifugal force.

And before this color mortar layer (4) hardens,
Ordinary concrete is poured into the colored mortar layer (4) of the molding form (1), centrifugal force is applied again to form a hollow concrete body (5), and steam curing is performed to achieve the specified strength. Obtain and demold.

Then, a surface protective agent of, for example, an oil-based synthetic resin is applied thinly to the colored mortar layer (4), and air curing is performed.

Among the components of color mortar, the cement used is normal cement or white cement, and the coloring agent used is pigment, seed color (highly concentrated pigment mixed with cement), or colored cement (white cement). (Cement mixed with pigment to give the desired color) is used.

In addition, if the thickness of the colored mortar layer (4) is too thin, it will be affected by the color of the internal concrete body (5) and the desired color will not be obtained; on the other hand, if it is too thick, the material The cost is high, and the coarse aggregate is used in the concrete body (
Color mortar layer (4) will be biased towards the center of layer 5), resulting in a large decrease in strength.
The appropriate thickness is 5 to 10 degrees.

Then, in order to confirm the strength of the composite concrete pole by forming the color mortar layer (4),
A centrifugal specimen with a diameter of 0cm, a height of 30cm, and a thickness of 4cm was made, and the demolding strength after atmospheric pressure steam curing and the 14-day aging strength were compared with ordinary concrete poles using the JIS A 1136 test method. This was done through an experiment.

Materials used are: 0 cement, ordinary portland cement made by ○, 0 fine aggregate, 0 land sand 0 coarse aggregate, made for Kinu, 0 cobblestone crushed stone, made for Kinu, colorant, pigment, Light green 5G made by company B, O admixture, Mighty 150S centrifugal modeling made by company K. is as follows.

0 For composite concrete poles: Adding colored mortar → centrifugal compaction step 1 - Adding normal concrete - Centrifugal compaction step 2 0 For normal concrete poles: Adding normal concrete - centrifugal compaction stencil 2 The above centrifugal compaction step 1 and the same steps The conditions of 2 are shown in Tables 1 and 2, respectively.

Test results (1) Compressive strength The test results in Table 3 are shown in Figure 2. In the case of composite concrete, no decrease in strength due to the colored mortar layer was observed, and the compressive strength was slightly thicker than that of ordinary concrete ( It has become.

(2) Cross-sectional structure of composite concrete When the specimen was cut longitudinally in the cylinder length direction and its cross section was observed, coarse aggregate appeared in the color mortar layer in the form of bite, which caused a decrease in the strength of the color mortar layer. The situation was found to be preventing this.

(3) Economical efficiency of composite concrete pole A concrete pole with a length of 14 m, a load of 500 kg, a taper of 1/75, and an end diameter of 19C11 was compared with the colored composite concrete pole according to the present invention and the conventional colored colored ball. (Pigment mixed into the entire concrete)
As a result of comparing the costs of each concrete material, it was found that colored composite concrete poles can be reduced in price by about 34% to 53% compared to conventional colored balls.

Although autoclave curing was not performed in the above-mentioned embodiments, it is of course possible to perform high-temperature and high-pressure steam curing treatment when carrying out the present invention.

[Effects of the Invention] In forming a concrete pole by centrifugal force forming, the present invention first injects colored mortar into the formwork and forms a thin outer shell of colored mortar with a thickness of 5 to 10 mm by centrifugal force forming. Because of this, the colors are evenly distributed, resulting in a uniform hue.

Furthermore, since the outer shell is 5 to 10 mm, the material cost is not high. In addition, since ordinary concrete is injected into the outer shell as coarse aggregate and the concrete pole is formed by centrifugal compaction again, the coarse aggregate does not shift toward the center of the concrete pole, increasing the overall strength. can be maintained sufficiently. Furthermore, unlike finishing the surface pattern by manual labor, colored composite materials for concrete poles can be obtained extremely easily and quickly.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a partial vertical side view of a formwork showing the state of forming a composite concrete pole, and Fig. 2 is a chart showing compressive strength. (1)・・・Molding formwork (2)・・・・・・
・Reinforcement cage (3)...PC steel material (4)・
...Mortar layer (5) ...Concrete main body patent applicant: Japan Concrete Industries Co., Ltd. Figure 1 Figure 2

Claims (1)

[Claims] When molding concrete poles using centrifugal force forming, color mortar is injected into the formwork and centrifugal force forming is used to form concrete poles.
This colored composite concrete pole is characterized in that a 0 mm thin-walled colored mortar outer shell is molded, ordinary concrete is poured into the outer shell, and centrifugal force molding is performed again.