JPS623903A - Manufacture of concrete product - 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 [Industrial Field of Application] The present invention is directed to a method for manufacturing concrete products, and more particularly to a method for manufacturing concrete products whose surface has been decorated by exposing the aggregate.

[Conventional technology]

Methods for finishing concrete products include tiling, stone laying, color mortar coating, uneven patterns using rubber forms, painting, and finishing with exposed aggregate on the concrete surface.

Washing finish is often used to haze aggregate. In this method, a curing retarder is applied to the surface of the mold, or paper or cloth impregnated with a curing retarder is pasted on the surface of the mold, relatively soft concrete is poured in, and the mold is removed the day after pouring and hardened. There are methods to remove the mortar part on the surface of the molded body where the hardening is delayed and to spread the aggregate on the surface, or to bury a part of the aggregate in clay that does not harden or a mixture of water-soluble glue and sand. Relatively soft concrete is poured over the aggregate according to the method described above, and after the concrete has hardened the day after pouring, it is removed from the mold, and then the clay, glue and sand mixture, etc. are washed away and the aggregate is poured. There are methods to expose the mortar, and methods to wash away the mortar part by pouring water on it when the immediately demolded concrete molded body is not yet hardened.

There is also a method of using a tool, but this method involves using a chisel to remove the mortar on the surface of the concrete after it hardens, using a chiseling tool, or by hitting the surface with a variety of hammers. There is a finishing method that removes the mortar and some of the aggregate on the surface.

Other methods include a grinder finishing method in which the surface is polished with a grinder, and a polishing method using a whetstone.

Other methods include a blast finishing method in which iron particles or hard sand are sprinkled onto the surface of a concrete molded body and the mortar on the surface and part of the aggregate surface are scraped off, and the mortar on the surface of the concrete molded body is peeled off by vacuuming to remove the aggregate. There are ways to expose it.

Furthermore, after the concrete components have hardened, a method is also used in which the hardened concrete is removed by dissolving the mortar with a chemical such as hydrochloric acid and shaking the aggregate.

[Problem that the invention seeks to solve]

In the washing-out finishing method using the concrete hardening retardant, it is necessary to take into account that the concrete components will harden, and not to lose the timing of washing out the concrete components on the surface. . In addition, it is difficult for the retardant to act uniformly on the surface, making it difficult to achieve a uniform washout finish, and as a result, uneven washout is likely to occur. Furthermore, in the washing-out finishing method that uses clay or water-soluble glue, the labor of embedding aggregate before concrete is poured and the washing-out work after demolding are more troublesome than methods that use concrete hardening retarders.

In the washing-out method after immediate demolding, it is difficult to completely remove the paste to be washed out, and the aggregate is likely to be contaminated. Furthermore, since the concrete is washed out before it hardens, the product is easily damaged, and it is difficult to adjust the strength of the washing water stream.

The chiseling and pounding methods, which use tools to finish the concrete after it has hardened, often result in damage such as chipped corners, loosening of the aggregate, and require a shallow finishing depth, which requires a lot of effort.

Polishing with a grinder or whetstone produces a smooth finish and gives the aggregate a beautiful cross-section, but it does not give the flavor of the aggregate itself. Additionally, the method of polishing the surface may leave traces of air bubbles inside, requiring repair.

The blasting method and the vacuum mortar removal method have shallow finishing depths and are unsuitable for hazing large aggregates.

The cleaning method using hydrochloric acid is not only dangerous, but also requires consideration in terms of environmental pollution.

Furthermore, in all of the methods described above, except for the method of immediately removing the mold and immediately washing it out, after pouring concrete with a large comparative ramp, the mold is removed from the pouring hole and the respective operations are carried out. Bad sex. Moreover, both methods have the disadvantage of generating waste such as washing water, washing scum, chips, and shavings.

[Means for solving problems]

As a result of our research to provide a new method for manufacturing concrete products that eliminates the drawbacks of conventional methods, we poured cemented carbide concrete with a slump of 0 to 1 cm into the formwork so that the top of the formwork was transparent. to form a concrete layer, and furthermore, on the concrete layer,
m of aggregate is spread, pressed onto concrete, and then compacted, the concrete is pushed up to the top of the formwork, thereby exposing the concrete.The aggregate adheres to the aggregate without staining the surface of the aggregate. The present invention was completed based on the knowledge that concrete products with a surface decoration can be manufactured with high productivity and without polluting the environment.

The gist of the present invention is to form a concrete layer by pouring cemented carbide concrete with a slump of 0 to 1 cm into a formwork so that the upper part of the formwork is transparent, and to form a concrete layer on top of the concrete layer.
The method for producing a concrete product is characterized by laying 200 mm of aggregate, pressing it against concrete, compacting it, and removing it from the mold.

The degree of hardness of cemented carbide concrete varies depending on the compaction method, but regardless of the compaction method, excess water (including cement) is squeezed out during compaction and flows, causing surface problems. It is necessary to avoid contaminating exposed aggregates.

However, if the amount of water is too low, the adhesion between the vibrating aggregate and the cemented concrete will be weakened.

Therefore, water (including cement) oozes out during compaction, but it must be hard enough not to flow out, and the slump must be O~1. About cm is appropriate.

As a method for compacting concrete, a method using pu-nos, a method using vibration, a method of applying vibration while pressing, etc. can be applied.

〔Example〕

Next, the present invention will be explained with reference to examples.

Example 1 A face plate 3 was placed on the bottom of the formwork 2 on the surface plate 6 shown in FIG.
On top of that, zero slump concrete 1 is spread to a thickness of 15 cm, and on top of that, aggregate 4 with a size of 50 to 100 mm is spread, and compacted by applying vibration to the formwork 2 while pressing with the upper press 5. I did it.

Next, the molded body was extruded from the formwork 2 and a concrete product was obtained after curing. The resulting concrete product (
Figure 2) is aggregate 4 without soiling the surface with concrete.
The surface was beautifully decorated.

Comparative Example 1 Comparison was carried out in the same manner as in Example 1 except that concrete with a slump of 1.5 cm was used instead of concrete with zero slump. However, the aggregate 4 settled in the concrete and the surface became dirty, making it impossible to obtain a satisfactory concrete product. Since the finish is completed immediately upon demolding without spilling out, it is possible to achieve a beautiful finish without staining the surface of the aggregate that comes out or spoiling its taste. This is particularly effective when using aggregate with a rough surface, such as lava rock.

In addition, since there is no finishing process unlike in the past, there is no damage to the product or floating of aggregate, and no waste is generated, resulting in high productivity.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing the state in which concrete is spread on a formwork and =8- aggregate is spread on top of it, and the side plates of the formwork are removed, and Figure 2 is a compacted compact. shows. 1: Carbide mixed concrete 2: Side plate template 3: Face plate 4: Aggregate 5: Upper press 6: Surface plate Patent applicant Fuji Special Concrete Industry Co., Ltd. Japan Cement Co., Ltd. Agent Patent attorney Tsukasa Sumono Tsukasa Figure 1 Figure 2

Claims (1)

[Claims] (1) Pour cemented carbide concrete with a slump of 0 to 1 cm into the formwork so that the top of the formwork is transparent to form a concrete layer, and then place cemented carbide concrete with a size of 5 to 2 cm on top of the concrete layer.
A manufacturing method for concrete products characterized by laying 00mm aggregate, pressing it onto concrete, compacting it, and removing it from the mold.