JP7619780B2 - Manufacturing method of PCa products using top vibrator - Google Patents

Description

The present invention relates to a top vibrator that can compact concrete while simultaneously smoothing and finishing the top edge, and a manufacturing method for PCa products using the same.

PCa (precast) products such as PCa floor slabs are made in factories etc. by applying the necessary reinforcement to formwork, pouring concrete into it, compacting it with a vibrator etc., and then allowing the concrete to harden after a certain amount of time has passed to become a PCa product. In addition, after the concrete has hardened to a certain extent, but before it hardens completely, the top surface of the PCa product needs to be smoothed with a trowel.

For example, Patent Document 1 discloses a method for manufacturing PCa products, which includes the steps of pouring a mixture of concrete raw materials containing hydraulic cement, color aggregate, pigment, and water onto a table vibrator that constitutes the bottom surface of the concrete pouring space, pouring and spreading the mixture onto the table of the table vibrator under the vibration and compacting action of the table vibrator to form the surface layer of a hardened concrete body with a specific gravity of 2.3 or more, stopping the table vibrator and allowing a predetermined drying and hardening time to pass, pouring lightweight concrete onto the surface layer to form the back layer of the hardened concrete body with a specific gravity of 2.1 or less as the back layer of the surface layer, and removing the concrete molded body having a multi-layer structure of the surface layer and back layer, and then performing a surface treatment on the exterior surface of the surface layer to expose a part of the color aggregate on the exterior surface (see claim 1 of Patent Document 1, paragraphs [0020] to [0035] of the specification, and Figures 1 to 4 of the drawings, etc.).

However, the PC panel manufacturing method described in Patent Document 1 is a method for manufacturing PC panels with a multi-layer structure that has a highly aesthetic design, and if the surface of the top edge that does not come into contact with the formwork is to be finished smoothly without sandblasting, it still needs to be smoothed with a trowel.

In addition to the usual rod-shaped vibrator used to compact concrete, Patent Document 2 discloses a method of compacting concrete by attaching a punched metal with many holes to a usual rod-shaped vibrator (see Figures 4 to 6 of Patent Document 2).

However, the vibrator described in Patent Document 2 can only compact the concrete, but cannot smooth it out, so a skilled worker such as a plasterer must separately assess the degree of hardening of the concrete and smooth the top surface of the concrete with a trowel.

In particular, when pouring high-strength concrete, the aggregate does not sink, so it is necessary to press it down with a wooden trowel to make the aggregate sink, and then finish it off again with a metal trowel to make it smooth, which is time-consuming and can only be completed by experienced workers.

JP 2009-196333 A Publication No. 4-54268

The present invention was devised in consideration of the above-mentioned problems, and its purpose is to provide a top vibrator that can compact the concrete while simultaneously smoothing and finishing the top edge, and a manufacturing method for PCa products using the same.

The manufacturing method of a PCa product using a top vibrator of claim 1 is a manufacturing method of a PCa product in which concrete is poured into a formwork for a PCa product and the surface that will become the top end is finished smoothly, and after concrete is poured into the formwork and compacted using a general rod-shaped vibrator , a top vibrator having a smooth bottom plate that is longer than the short side length of the formwork and connected to a vibration device is hung above the formwork in the short side direction, and the top vibrator is vibrated by the vibration device to compact the concrete while the smooth bottom plate of the top vibrator is moved along the long side direction of the formwork, thereby simultaneously compacting the concrete and finishing the surface that will become the top end smoothly.

The method for manufacturing a PCa product using the top end vibrator of claim 2 is characterized in that, in the method for manufacturing a PCa product using the top end vibrator of claim 1, after high-strength concrete is poured into the formwork, the top end vibrator is used to simultaneously compact the high-strength concrete and smooth the surface.

According to the inventions of claims 1 and 2 , when manufacturing PCa products, the concrete can be compacted and the top surface can be finished smoothly. This eliminates the need for a skilled worker to be present during pouring of the concrete, determine the degree of hardening of the concrete, and smooth the top surface of the concrete with a trowel, which can resolve the shortage of workers and reduce the manufacturing cost of PCa products.

In particular, according to the invention of claim 2, the problem of aggregates not sinking easily, which is unique to high-strength concrete, can be solved by applying vibrations evenly to the surface of the concrete, which not only makes it possible to compact it, but also allows the top surface to be finished at the same time.

FIG. 1 is a side view showing a top end vibrator according to an embodiment of the present invention. FIG. 2 is a vertical cross-sectional view of a formwork for a PCa product, showing the use of the top end vibrator. FIG. 3 is a process explanatory diagram showing the formwork assembly process of the manufacturing method for a PCa product using the top end vibrator according to this embodiment. FIG. 4 is a process explanatory diagram showing the reinforcing bar arrangement process of the manufacturing method of the PCa product using the above-mentioned top end vibrator. FIG. 5 is a process explanatory diagram showing the concrete pouring process of the manufacturing method of a PCa product using the above-mentioned top end vibrator.

Below, one embodiment of a method for manufacturing PCa products using a top-end vibrator according to the present invention will be described in detail with reference to the drawings.

First, the top vibrator 1 according to an embodiment of the present invention will be described with reference to Figures 1 and 2. Figure 1 is a side view showing the top vibrator 1 according to an embodiment of the present invention, and Figure 2 is a vertical cross-sectional view of a formwork K for a PCa product showing the use of the top vibrator 1 according to this embodiment. In the figure, the X direction is the short side direction of the formwork K for the PCa product, and the Y direction is the long side direction. The Z direction is the up-down direction (same below).

As shown in FIG. 1, the top vibrator 1 according to this embodiment is a device consisting of a rod-shaped vibrator 2 and a square pipe 3 connected and fixed to the rod-shaped vibrator 2. The top vibrator 1 has the function of compacting the concrete C1 poured into the formwork K and smoothing the surface that will become the top.

(Rod-shaped vibrator)
As shown in Fig. 1, this rod-shaped vibrator 2 is a commercially available handy electric rod-type vibrator without a flexible resin tube portion. This rod-shaped vibrator 2 is composed of a vibrator body 21 having an electric motor 20 as a vibration device, a rod portion 22 attached to the tip of the vibrator body 21, a handle 23 attached to the rear end of the vibrator body 21, etc.

This rod-shaped vibrator 2 has a vibration device that generates a vibration force by rotating an eccentric weight (not shown) provided in the vibration part 24 of the rod part 22 with an electric motor 20. Of course, the rod-shaped vibrator 2 is not limited to a handheld type, and may be any vibrator that has a vibration device that generates a vibration force, such as a high-frequency vibrator, and has a vibrating rod-shaped vibration part such as the rod part 22.

(Square tube)
The square tube 3 according to this embodiment is an aluminum square tube with a longitudinal length H1 and a rectangular cross section perpendicular to the longitudinal direction, as shown in Fig. 1. As shown in Fig. 2, this square tube 3 is attached to the rod-shaped vibrator 2 so that the long side direction of the rectangular cross section is in the vertical direction Z perpendicular to the formwork K so that it is less likely to bend. In addition, the length H1 of this square tube 3 needs to be longer than the length H2 of the short side direction X of the formwork K for the PCa product, since it is placed on the formwork K for the PCa product.

However, this square tube 3 is not limited to an aluminum square tube, but can be a metal strip such as a grooved frame or L-shaped angle that has a certain strength, such as ordinary steel material. In other words, the member connected to the vibration device of the vibrator according to the present invention is a strip that can transmit the vibration of the vibrator to the concrete, and it is sufficient that it has a smooth bottom plate with a smooth bottom surface that can level the top surface of the concrete.

As shown in Figures 1 and 2, the rod-shaped vibrator 2 and the square tube 3 are firmly connected and fixed by the rod portion 22 and the connecting fitting 4, and by the handle 23 and the cable tie 5, respectively, so that the vibrations generated by the rod-shaped vibrator 2 are transmitted to the square tube 3.

As an example of the top vibrator 1, a commercially available rod-shaped vibrator 2 connected to an aluminum square tube 3 was used. However, the top vibrator 1 is not limited to a commercially available vibrator, and may be a metal strip with a smooth bottom plate and longer than the length H2 of the short side direction X of the formwork K, directly connected to the vibration device that generates the excitation force.

Next, a method for manufacturing a PCa product using the top end vibrator 1 according to an embodiment of the present invention (hereinafter simply referred to as a method for manufacturing a PCa product) will be described with reference to Figures 2 to 5. A PCa floor slab will be used as an example of a PCa product. Of course, the PCa product is not limited to a PCa floor slab, and the method can be applied to a PCa product that is manufactured by pouring and hardening concrete in a factory or the like, and then transported to the site.

(1. Formwork assembly process)
As shown in Fig. 3, in the manufacturing method of the PCa product according to this embodiment, first, a form assembly process is performed to assemble a form K having a rectangular shape in plan view for the PCa floor slab. Fig. 3 is a process explanatory diagram showing the form assembly process of the manufacturing method of the PCa product using the top end vibrator according to this embodiment.

(2. Reinforcement process)
As shown in Fig. 4, in the manufacturing method of the PCa product according to the present embodiment, a reinforcing bar arrangement process is then performed in which predetermined reinforcing bars S (deformed steel bars) are arranged in the form K assembled in the form assembly process. Fig. 4 is a process explanatory diagram showing the reinforcing bar arrangement process of the manufacturing method of the PCa product according to the present embodiment.

(3. Concrete pouring process)
As shown in Fig. 5, in the manufacturing method of the PCa product according to the present embodiment, a concrete pouring step is then performed to pour concrete C1 into a formwork K in which a predetermined number of reinforcing bars S are arranged. Fig. 5 is a process explanatory diagram showing the concrete pouring step of the manufacturing method of the PCa product according to the present embodiment.

In this process, high-strength concrete C1 is poured. In the Japan Society of Civil Engineers' Standard Specifications for Concrete, high-strength concrete is defined as "concrete with a design strength of 50 to 100 N/ ^mm2 ." As mentioned in the Background Art section, when the concrete to be poured is high-strength concrete, there is a problem that the aggregate does not easily sink. Of course, it goes without saying that normal strength concrete may be poured in this process.

In general, when pouring concrete, a handheld electric vibrator or high-frequency vibrator such as the rod-shaped vibrator 2 is used to compact the concrete as it is poured, causing the aggregate to sink. However, when pouring high-strength concrete, such a rod-shaped vibrator alone can only sink the aggregate in the immediate vicinity of the area where the rod-shaped vibrator was inserted. For this reason, when pouring high-strength concrete in the past, it was necessary to press down with a wooden trowel to sink the aggregate and remove any traces of where the rod-shaped vibrator was inserted, and then finish off the surface smoothly with a metal trowel.

(4. Top end finishing process)
In the method for manufacturing a PCa product according to this embodiment, as in the conventional method, concrete is poured and compacted using a general rod-shaped vibrator such as the rod-shaped vibrator 2. However, as shown in Fig. 2, in the method for manufacturing a PCa product according to this embodiment, next, a top vibrator 1 is used to compact the high-strength concrete poured into the formwork K, and a top finishing process is performed to smooth the surface that will become the top end.

In this process, the square pipe 3 of the top vibrator 1 is placed over the formwork K along the short side direction X, and the square pipe 3 is moved along the long side direction Y of the formwork K while being vibrated by a vibrating device to compact the poured high-strength concrete C1. Since the square pipe 3 is made of aluminum, it is lightweight and easy to handle, reducing the physical burden on the worker and allowing anyone to easily finish the surface.

Furthermore, as mentioned above, the square tube 3 is a frame body with an effective cross section that is rectangular with no open ends, and is placed so that its long side direction is the vertical direction Z perpendicular to the formwork K. For this reason, even though the square tube 3 is made of lightweight aluminum, it is difficult to bend, and the top edge of the PC deck can be finished smoothly without undulations or unevenness.

In this way, in this process, the surface of the poured high-strength concrete C1 is locally vibrated by the top vibrator 1 to sink the aggregate of the high-strength concrete C1, while being leveled by the flat bottom surface of the square pipe 3. This eliminates the need for a skilled worker to be present while pouring the concrete, determine the degree of hardening of the concrete, and smooth the top surface of the concrete with a trowel. This can alleviate the worker shortage and reduce the manufacturing costs of PCa products.

Note that after this process or its completion, the top edge of the PC deck can be finished again with a metal trowel or other trowel to make it flat. This is because the top edge of the PC deck can be finished even more smoothly and neatly. However, even in this case, the method for manufacturing PCa products according to this embodiment does not allow the aggregate to sink, as opposed to conventional manufacturing methods, and so it is clear that this reduces the workload of pressing down with a wooden trowel to make the aggregate sink, and then finishing it off smoothly with a metal trowel.

According to the top end vibrator 1 and the manufacturing method of PCa products using the top end vibrator 1 described above, when manufacturing PCa products, even high-strength concrete can be reliably compacted and the top surface can be finished smoothly. This eliminates the need for a skilled worker to be present during the pouring of the concrete, determine the degree of hardening of the concrete, and smooth the top surface of the concrete with a trowel. Therefore, this manufacturing method of PCa products can resolve the worker shortage and reduce the manufacturing costs of PCa products.

In addition, the square tube 3 of the top vibrator 1 is made of aluminum, so it is lightweight and easy to handle, reducing the physical burden on the worker and allowing anyone to easily finish the surface.

The above provides a detailed explanation of the method for manufacturing a PCa product using a top-end vibrator according to an embodiment of the present invention. However, the above-mentioned and illustrated embodiments are merely examples of specific embodiments for implementing the present invention. Therefore, the technical scope of the present invention should not be interpreted in a limited manner based on these.

In particular, although a PCa deck has been given as an example of a PCa product, the present invention is not limited to PCa decks, and can be applied to any PCa product in which concrete is poured and hardened in advance at a factory or the like, and which is then manufactured and transported to the site. However, because the surface of the present invention can be easily finished, it can be particularly effectively applied to plate-shaped PCa products with a large top surface area, such as PCa decks.

1: Top end vibrator 2: Rod-shaped vibrator 20: Electric motor (vibration device)
21: Vibrator body (vibration device)
22: Rod portion 23: Handle 24: Vibration portion (vibration device)
3: Square tube (smooth bottom)
H1: Length of the rectangular pipe in the longitudinal direction 4: Connection fitting 5: Cable tie K: Formwork (for PCa products) H2: Length of the formwork in the short side direction S: Reinforcement bar C1: High-strength concrete (concrete)

Claims (2)

A method for manufacturing a PCa product in which concrete is poured into a formwork for the PCa product to finish the top surface smoothly,
A manufacturing method for a PCa product using a top vibrator, characterized in that concrete is poured into the formwork and compacted using a general rod-shaped vibrator , and then a top vibrator with a smooth, flat bottom plate longer than the short side length of the formwork and connected to a vibration device is hung above the formwork in the short side direction, and the top vibrator is vibrated by the vibration device to compact the concrete while the smooth bottom plate of the top vibrator is moved along the long side direction of the formwork, thereby simultaneously compacting the concrete and smoothing the surface that will become the top end. A manufacturing method for a PCa product using a top end vibrator as described in claim 1, characterized in that after high-strength concrete is poured into the formwork, the top end vibrator is used to simultaneously compact the high-strength concrete and level its surface.

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