JPS5819442B2 - Manufacturing method for plate-shaped concrete products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing plate-shaped concrete products using a vacuum concrete method.

In this type of manufacturing method, water unnecessary for water use is removed from the concrete immediately after pouring into the formwork, so the water-cement ratio of the concrete is reduced, the concrete is compacted, and the initial strength and long-term strength are improved. It has the advantage of producing a heavy concrete product with high strength.

・Also, because the concrete hardens quickly, the formwork can be taken out quickly and the formwork turnover rate is high.

However, in the past, the formwork was removed after the concrete poured into the formwork was cured, so the turnover rate of the formwork was not yet high enough.

The present invention is for immediate demolding in order to further increase the turnover rate of molds.

Specifically, a frame with open top and bottom surfaces is placed on top of a base with a decompression chamber formed, the base and frame are separably connected, and a large number of small holes communicating with the decompression chamber of the base are formed. Using a formwork with the open upper surface of the base and the lower surface of the frame closed, a filter cloth is laid on the upper surface of the base inside the frame, concrete is poured into the frame, the pressure is reduced in the vacuum chamber, and water and cement in the concrete inside the frame are removed. After compacting the concrete by lowering the ratio, the formwork is turned over while the decompression chamber is depressurized, and the concrete molded product formed by compacting the concrete is placed on the curing board inside the frame of the inverted formwork. The depressurization in the decompression chamber is released, the base and frame are separated, the frame is removed from the concrete molded product placed on the curing board, and the concrete molded product with the formwork removed is cured on the curing board. This is a manufacturing method for plate-shaped concrete products.

According to the manufacturing method of the present invention, since the formwork is removed before curing the concrete molded product, the time for removing the formwork is early, and compared to conventional methods, the use rate of formwork is higher (and cheaper). This has the effect of making it possible to manufacture plate-shaped concrete products.

Next, examples of the present invention will be described.

The formwork 1 used in this example is as shown in FIGS. 1 and 2,
It is composed of a shallow rectangular box-shaped base 2 and a rectangular frame 10, and the box-shaped base 2 has a large number of small holes 4 penetrated at equal intervals on the entire surface of the top plate, and a center position on the outer surface of one side plate. A short circular pipe 5 is provided protruding from the base body 2, and a hole penetrated at the same position communicates with the center hole of the circular pipe 5 to form a discharge hole 6, and the inside of the base body 2, which communicates with the outside through the discharge hole 6, is depressurized. A bifurcated mounting piece 7 is formed in the chamber 3, and a bifurcated mounting piece 7 is provided protruding from both end positions of the outer surface of both side plates, and a flange 8 is provided protruding from the upper end of the outer surface of the four peripheries. Place it in line with the top surface of the top plate where it is opened,
7 A required number of bolt insertion holes 9 are penetrated through the flange 8 at appropriate intervals, and a rectangular frame 10 having the same size as the base body 2 has flanges that overlap with the flanges 8 of the base body at the lower ends of the outer surfaces of the four peripheries. 11 is provided protrudingly, and the bolt insertion hole 9 of the base body is inserted into the 7 flange 11.
A frame body 10 with open upper and lower surfaces is placed on the base body 2, and a bolt insertion hole 12 communicating with
The flange 11 of the frame body is superimposed on the flange 8 via the backing, and the bolts 13 are inserted into the required number of bolt insertion holes 9 of the base body and the bolt insertion holes 12 of the frame body that communicate with each other, and the protruding tips of each bolt are inserted. Screw the nuts 14 into each part,
Each bolt 13 and nut 14 is tightened, and the frame 10 is separably coupled to the base body 2 with the required number of bolts 13 and nuts 14, and the base body 2 is formed with a large number of small holes 4 communicating with the decompression chamber 3.
The open lower surface of the frame body 10 is closed by the upper surface.

On the other hand, as shown in FIG. 2, both support shafts 11° 17 protruding from the center positions of both end faces of the rectangular plate-shaped reversing plate 160 are pivotally supported at the upper ends of both support plates 18, 18 arranged in parallel, and one supporting shaft 17
A reversing machine 15 connected to a brake motor 20 with a reducer via a chain transmission mechanism 19 is prepared, and the formwork 1 is placed on the horizontal reversing plate 16 of this reversing machine 15. The formwork is fixed to the reversing plate 16 with bolts and nuts 21 using bifurcated attachment pieces I protruding from the four corners, and a vacuum pump 23 is connected to the discharge hole 6 of the formwork via a flexible tube 22.

A filter cloth 24 is spread on the upper surface of the base 2 in the upwardly opened frame 10 of the form 1 installed in the reversing machine 15, as shown by the chain line in FIG. All the small holes 4 that are connected and opened on the upper surface of the base body 2 are covered with a filter cloth 24, and the frame body 1 is
After arranging reinforcing bars and pouring concrete into the container 0, leveling the upper surface of the concrete so that it matches the upper edge of the frame 10, the vacuum pump 23 is activated.

Due to the operation of the vacuum pump 23, the inside of the decompression chamber 3 is drained from the exhaust hole 6,
It is exhausted and depressurized through the flexible tube 22,
Water in the concrete in the frame 10 and air sealed in the concrete during pouring flow into the vacuum chamber 3 through the small holes 4 through the filter cloth 24, and the water and air flowing into the vacuum chamber 3 The water is discharged through the discharge hole 6, the flexible tube 22, and the vacuum pump 23, and the water-to-cement ratio of the concrete in the frame 10 decreases, so that the concrete in the frame 10 is compacted.

After the water/cement ratio of the concrete in the frame body 10 has decreased to about 25%, the brake motor 20 of the reversing machine is driven while the vacuum pump 23 continues to operate to reduce the pressure in the decompression chamber 3, and the reversing plate 16 Turn the frame 1 half a turn around both horizontal support shafts 17 and 1γ, and turn over the formwork 1 in which the concrete molded product 25 has been formed by compacting the concrete within the frame body 10, as shown by the solid line in Fig. 3. .

Rail 26 laid through the lower position of the inverted formwork 1
．． A wooden curing plate 31 mounted on the trolley 21 is moved to a position below the formwork 1 by moving the trolley 21 on the trolley 26 via a table lifter 28 with a table 30 fixed on a plurality of interlocking hydraulic jacks 29. Place it in the minecart 27
Hydraulic jack 29 of table lifter 28 installed above
The curing plate 31 placed on the table 30 of the table lifter is raised until it comes into contact with the downward facing frame 10 and the concrete molded product 25 sucked into the frame, and the curing plate 31 placed on the table 30 of the table lifter is raised until it comes into contact with the downwardly facing frame 10 and the concrete molded product 25 sucked into the frame. As shown by the chain line, the concrete molded product 25 inside the frame 10 is placed on the curing plate 31.

Thereafter, the operation of the vacuum pump 23 is stopped to release the reduced pressure in the decompression chamber 3, and the bolts 13 connecting the frame 10 supported by the curing plate 31 and the base body 2 fixed to the reversing plate 16 of the reversing machine , remove the nut 14 and remove the frame 10 on the curing plate 31.
and the base body 2, lowering the table 30 by lowering the hydraulic jack 29, and lowering the curing plate 31 on which the concrete molded product 25 in the frame body 10 is placed.
The trolley 27 located below the base 2 is moved to move the concrete molded product 25 inside the frame 10 placed on the curing plate 31 on the trolley 27 away from the lower position of the base 2, as shown by the solid line in FIG. As shown in FIG. The filter cloth 24 stuck to the top surface of the concrete molded product 25 is removed, and the concrete molded product 25 on the curing plate 31 is left to cure, while the brake motor 20 of the reversing machine is driven to remove the formwork. The reversing plate 16 to which only the base body 2 is fixed is rotated by half a turn, and the base body 2 is returned to its original position as shown by the chain line in FIG.

The frame 10 extracted from the concrete molded product 25 is placed on the base 2 facing upward, and the flange 8 of the base and the 7 flange 11 of the frame are fixed with bolts 13 and nuts 14.
As shown in FIG. 2, a frame 10 is bonded onto the base 2.

Again, a concrete molded product is manufactured by the same process as the previous time, such as laying a filter cloth inside the frame body 10 of the formwork and pouring concrete, while placing the previously manufactured concrete molded product 25 on the curing board 31. The concrete is cured to produce rectangular flat plate reinforced concrete products.

In the above embodiments, reinforced concrete products are produced, but unreinforced concrete products can also be produced.

In addition, a flat plate-shaped concrete product with a flat plate surface is manufactured using a formwork 1 with a flat top surface and a base body 2 that closes the bottom surface of the frame body 10, but a formwork with an uneven top surface of the base body is manufactured. It is also possible to manufacture a plate-shaped concrete product with an uneven plate surface using the method.

Further, bolts 13 and nuts 1 are used to connect the base body 2 and the frame body 10.
4 is used, but instead of the bolts 13 and nuts 14, a formwork using a coupling tool with a U-shaped cross section that fits into the flange of the polymerized base and the flange of the frame body is used. It is also possible to omit the labor involved in bolt tightening.

Although the formwork 1 in which the frame body 10 is integrally formed is used, a formwork in which the frame body can be divided into two parts is used to facilitate the removal of the frame body from the concrete molded product. You can also.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the formwork used in the example, Fig. 2 is a longitudinal cross-sectional view showing the formwork installed in a reversing machine, and Fig. 3 is a longitudinal cross-sectional view showing the formwork inverted. FIG. 4 is a longitudinal sectional view showing a state in which the base body and frame body of the same formwork are separated. 1: Formwork, 2: Substrate, 3: Decompression chamber, 4: Small hole, 10: Frame, 24: Filter cloth, 25: Concrete molded product, 3: Curing plate.

Claims (1)

[Claims] 1. A frame with open top and bottom surfaces is placed on a base with a decompression chamber formed thereon, and the base and frame are separably coupled, and the top surface of the base has a number of small holes communicating with the decompression chamber of the base. Using a formwork with the bottom side of the frame closed, a filter cloth is placed on the top surface of the base inside the frame, concrete is poured into the frame, and the pressure in the vacuum chamber is reduced to reduce the water/cement ratio of the concrete inside the frame. After compacting the concrete, the formwork is turned over while the vacuum chamber remains depressurized, and the concrete molded product formed by compacting the concrete is placed inside the frame of the inverted formwork on a curing board, and then the vacuum chamber is closed. A board characterized by releasing the reduced pressure, separating the base and frame, removing the frame from the concrete molded product placed on the curing board, and curing the concrete molded product from which the formwork has been removed on the curing board. Manufacturing method for shaped concrete products.