JPS6149086B2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention has a rough surface because the surface is not smooth and the surface gravel and coarse sand protrude slightly from the cement and fine sand mortar. Concerning the manufacturing method of concrete products.

(Prior Art) Conventionally, there is a washout method as a method for creating the above-mentioned rough surface. In this method, a hardening retardant is added to the surface layer of the concrete, and when other parts of the concrete have hardened, the unhardened surface layer mortar is washed away with water. Although it is called washing with water, a brush or the like is used to scrub away the mortar, and the gravel (usually decorative gravel) is exposed to a large extent, increasing its aesthetic value.

(Problems to be Solved by the Invention) The above-mentioned washing method requires manual labor for both the application of a curing retarder and the washing with water, and is unsuitable for automation and mass production.

This invention aims to develop a new manufacturing method for mass producing rough concrete products that do not require as much difference in height as the washing method described above, without the cumbersome hardening delay treatment and washing work.

(Means for Solving the Problems) This invention involves filling hardened concrete into a formwork and forming it, and before curing it, a small amount of water is sprayed, removed, or applied onto the upper surface of the formed concrete. This gives fluidity to the cement and fine-grained sand in the surface layer, allowing them to settle into the interstices between the gravel and coarse-grained sand in the surface layer by gravity, lowering the surface level to a level lower than the initial top surface of the concrete, and then curing. This is a manufacturing method for rough concrete products. In addition, a water reservoir band is attached to the outer circumference of the upper surface of the concrete to supply water, and the band is removed for curing.

(Function) Because the mortar in hardened concrete has little moisture, it often acts like a bridge between the gravel and cannot move. Therefore, when water is added to it, it gains fluidity and settles into the gaps between gravel and coarse sand. As a result, the gravel and coarse sand on the upper surface become higher than the settled mortar, and the desired rough surface can be obtained.

The water reservoir band fitted around the outer circumference of the concrete top surface not only prevents water from flowing down from the top surface to the sides, but also has the effect of uniformly distributing water over the entire top surface.

(Example) FIG. 1 shows a schematic cross-sectional view of a form M filled with hardened concrete C. A mortar component 2 consisting of cement or fine-grained sand is packed between the gravel or coarse-grained sand 1, or unlike poured concrete, hardened concrete leaves many voids (not shown). When pouring concrete, it is divided into two layers, with the lower part using the normal mix and the upper part using concrete with a mix that has a particularly large number of voids, or artificially reducing the voids by slightly refraining from vibration and pressure after the concrete is poured. You can increase it.

In Figure 2, the surface layer mortar 2 is concrete C.
It settles inward, and coarse sand 1 protrudes a little from the surface layer,
Shows the desired rough surface.

Figures 1 and 2 are examples of adding water before demolding.
Figure 3 is an example of applying water after demolding. In this case, in order to prevent the water from overflowing from the outer periphery of the upper surface, a water reservoir band 3
is wearing. This band 3 gives plenty of water,
It also serves to replenish water while the mortar is settling, and to prevent the corners of the concrete from collapsing due to the water. Band 3 was made from a rubber plate and a rubberized plate in the experiment. As shown in Figure 4, the sprayed water 4 initially forms a puddle, but it is soon absorbed by the mortar and sinks. FIG. 5 shows the resulting roughened surface. In this way, once enough water is applied to form a puddle, the water is distributed evenly over the entire surface, which has the effect of obtaining an evenly roughened surface. However, if there is no risk of the corners of the concrete material collapsing when the applied water overflows, or if it is okay for the corners to collapse, sufficient water may be applied without attaching the band 3. Additionally, after concrete is poured, excess water may be sucked upward using a well-known vacuum drainage tool that is used when internal water rises to the surface.

Water is generally applied using a spray gun or a water drainer, but in the case of manual application, it may also be applied using a brush or other means.

In the case of gun spraying, the mortar on the surface layer tends to sink due to the impact of the water jet, and the mortar adhering to the top of the gravel is also washed away by the water. When applying water with a brush, a similar effect occurs due to the pressure and friction of the brush. Therefore, the phenomenon in which the hardened mortar acquires water, becomes fluid, and sinks into the concrete is mainly caused by gravity, but it is also thought that capillary action, injection, or pushing action by brushes are also effective.

The water given to the top surface is not necessarily fresh water. By adding a small amount of dilute hydrochloric acid or other acid to this as appropriate,
There is a phenomenon in which the appearance of the obtained rough surface is improved. This seems to be related to the fact that the acid neutralizes the alkalinity of the surface cement and partially dissolves it. In addition,
When acidic water permeates to the surface layer, it is neutralized.
There is no risk of adversely affecting the cement inside.

Further, a resin, a coloring agent, etc. may be added to the water applied to the surface layer. Even with water mixed with resin, there is no change in the effect of imparting fluidity to the mortar on the surface layer. and,
When the resin hardens, it can bond protruding gravel, coarse sand, and mortar to create a waterproof membrane. When the product of this invention, which is made by adding colorants and resins to water, is used as sidewalk paving stones, the result is a colorful, durable and impact-resistant promenade.

Next, an example of experimental data of this invention will be shown.

(Product name) Interlocking block (dimensions) Height 11cm, width 22cm, thickness 0.8cm (Concrete mixture) White cement 6.4Kg Ordinary cement 0.7Kg Granite sand (5m/m) 3.6Kg Granite sand (2.5m/m) 12 Kg Granite sand (2.5 or less) 9.6Kg Black mist (2m/m) 8.4Kg Water 1.7Kg (Effects of the invention) This invention has conventionally developed a surface with gravel or coarse sand protruding from the surface. This overturns the stereotype that processing is limited to washing out methods. This invention eliminates the need for cumbersome hardening delay treatment and water rinsing in the washout method, and simply forms hardened concrete and sprays, removes, or applies a small amount of water before or after immediate demolding. That's fine. The principle of forming a rough surface is that the surface mortar is not washed away, but sinks into the concrete.
This simplifies the work.

Traditionally, the wash-out method has been applied mostly to pour-forming equipment for concrete with a high moisture content;
Since this invention uses equipment for immediately demolding hardened concrete, productivity is dramatically increased.

[Brief explanation of the drawing]

Figures 1 and 2 are explanatory views of one embodiment of the present invention, and are partial cross-sectional views showing the state before and after a small amount of water is applied before demolding, and Figure 3 is a partial cross-sectional explanatory diagram showing the state before and after a small amount of water is applied to the concrete product after demolding. When applying a small amount of water to the surface layer according to the invention, a perspective view showing a state in which a water storage band is fitted around the outer periphery of the formed concrete, Fig. 4 shows a state in which the applied water is collected on its upper surface, and Fig. 5 shows the state in which the water is collected. FIG. 3 is a cross-sectional view showing a state in which the surface of the wafer has sunk and a rough surface has been formed. 1...Gravel, 2...Mortar, 3...Water band, 4...Water.

Claims (1)

[Scope of Claims] 1. Hardened concrete is packed in a formwork and formed, and before curing it, the surface layer is removed by spraying, removing, or applying a small amount of water on the top surface of the formed concrete. Gives fluidity to cement and fine sand,
After settling by gravity into the interstices between the surface gravel and coarse-grained sand and lowering it to a level lower than the original top surface of the concrete,
A method for manufacturing rough concrete products characterized by curing. 2. Fill hardened concrete into a formwork and form it, and before curing it, fit a water reservoir band around the top surface of the formed concrete, and spray, remove, or apply a small amount of water to the top surface of the concrete. This gives fluidity to the cement and fine-grained sand in the surface layer, allowing them to settle into the interstices between the gravel and coarse-grained sand in the surface layer by gravity, lowering the concrete to a level lower than the initial top surface of the concrete, and then curing. Manufacturing method for rough concrete products. 3. The method for producing a rough concrete product according to claim 1 or 2, wherein the small amount of water is acidic. 4. The method for producing a rough concrete product according to claim 1 or 2, wherein the small amount of water contains one or both of a resin and a colorant.