JPS58142803A - 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 The present invention relates to a method for manufacturing concrete products, and more particularly to a novel method for manufacturing concrete products by vibration or vibration-pressure.

There are currently three main methods for manufacturing concrete products such as concrete piles. That is, the first K is the vibration method, the second is the vibration-pressure method, and the third is the centrifugal forming method.

In the above-mentioned vibration method or vibration-pressure method, round shapes are conventionally formed using a formwork device as shown in FIG.

That is, a steel outer frame 1 and an inner frame 2 are arranged concentrically, a predetermined amount of concrete slurry (not shown) is poured into the gap 3 between the outer frame 1 and the inner frame 2, and the wrinkle slurry is In parallel with the pouring, immediately after the pouring, a predetermined vibration is applied to the lid frame device by an appropriate vibrating device, and the concrete slurry is made into a fluid state by the synergistic effect of the vibration and the gravitational acceleration f.
The slurry is gradually compacted by discharging the air in the slurry to create dense concrete.In addition to this, in the vibration-pressure method, a predetermined pressure is applied to the concrete after vibration compaction. The concrete is compressed as additional pouring, and at the same time the Kll frame opening (concrete slurry inlet) is finished forming.

+ Also, in Fig. 1, 5 is a bottom plate. However,
The sufficiently compacted round product develops the required strength through a predetermined steam curing process, and then the outer frame 1, inner frame 2, and bottom plate 5 are removed from the mold to complete the production of the required concrete product.

In addition, depending on the product, there is also a method of removing the mold from the above-mentioned curing 11111Km1 frame.

By the way, when demolding the above-mentioned part frame IK, approximately semicircular unit forms ta and lb are provided at the joint parts of the above-mentioned outer frame IK, and tightening means such as bolts of the fastening rib 4 are released. It is relatively easy to work on the arms as each mold needs to be removed outwards, but if you try to pull it out upwards in the figure with the inner frame 2 still in place, there will be a gap between it and the concrete. The adhesion force acts as a reaction force, making it impossible to easily remove the mold.
This will cause damage to the concrete before applying an undesirable external force.

Therefore, as shown in FIG.
121 and the main body 22,
1 Fi has a shape that converges downward at a predetermined angle, and the main body nv
The main body n has several tension means (turnbuckles in Fig. ) 23.

Then, from the slurry injection to the completion of curing process, the wedge 1121 and the main body n are connected by the so-called wedge effect, and in the demolding process, the wedge 1 is first
121 is pulled out, and then the remaining body n is pulled inwardly (toward the center) by the Joki Bow 1 tensioning means 23, and the body n is contracted in the direction of the arrow by the width of the upper rust I221. After this, a certain amount of space is created between the main body 22 and the concrete molded product, and the main body n is pulled out to perform dehumidification work.

In addition, 24 in the figure indicates wedge shapes 2 provided at appropriate intervals on the main body n.
This is the first position regulating and removal preventing member.

However, when the inner frame 2 having such a configuration is used, steps and joints are likely to occur at the joint portion with the wedge-shaped main body ρ, and these steps and joints appear directly on the inner surface of the concrete microcrystals, resulting in rounding. It is difficult to make the inner surface of the product smooth.

Further, when pulling out the wedge 1121 or contracting the main body n, unreasonable stress tends to be applied to the inner surface of the concrete product, which may cause damage or internal distortion.

However, as mentioned above, the demolding work is extremely cumbersome, and when the inner frame 2 is reassembled with snow, there is the same problem that the workability becomes cloudy.

In view of the above-mentioned points, the present invention aims to provide a method for manufacturing concrete products in which the formwork layering work of the inner frame is extremely easy, and the gist thereof is to The inner frame is expanded and contracted by vibration or vibration - steam curing after pressurization and subsequent temperature changes to create a slight gap between the inner frame and the concrete product. The purpose is to allow the inner frame to be easily pulled out and demolded by utilizing the gap.

Preferred embodiments of the present invention will be described below with reference to the drawings. Note that the same elements as those in the conventional example described above are indicated by the same symbols.

FIG. 2 is a schematic diagram showing a formwork apparatus A according to the manufacturing method of the present invention, in which l represents an outer frame, a 2Fi inner frame, and 5 a bottom plate.

In this embodiment, a hard vinyl chloride material whose linear expansion coefficient is relatively large compared to concrete is used as the inner frame 2, and the hard vinyl chloride material is integrally molded into a substantially cylindrical shape to form a seamless mold. forming a frame. In addition, the linear expansion coefficient of iron vinyl chloride material is 6 to 8 x 10-'/C
The outer frame l is made of steel and is large enough to be arranged concentrically with a predetermined gap 3 between the inner frame 2 and the inner frame 2. The unit formwork 1a and 1b having a substantially semicircular shape are formed at each end, and the fastening ribs 4, 4 are brought into contact with each other, and the fastening ribs 4 are bored. The mold is assembled by tightening the holes 41 with appropriate fastening means (not shown) such as bolts.

The bottom plate 5, the outer frame 1, and the inner frame 2 are similarly molded by appropriate means.

As mentioned above! In this embodiment, a predetermined concrete product is manufactured using a formwork machine in the following manner.

First, 10 units of outer frame and 1 formwork! I and 1b are fastened to each other as described above, and the inner frame 2 is arranged concentrically with a predetermined gap 3 between the outer frame l and the inner frame 2, and the outer frame l and the inner frame 2 are each tightly fastened to the bottom plate 5. Complete the prescribed molding.

Next, a reinforcing unit or the like is set in the gap 3 according to the target product, and concrete slurry 6 is injected. The concrete slurry 6 in the formwork shown in FIG. 3 is compacted by the vibration-pressure method.

Next, the concrete product together with the formwork A is steam-cured using an appropriate curing device (not shown) such as an autoclave. This steam curing is carried out at a temperature of Fiω to 80C for a required period of time.

During cough steam curing, the inner frame 2 is made of hard vinyl chloride material with a relatively high linear expansion coefficient as described above, so it expands by a predetermined amount (J) in the diametrical direction due to temperature rise, as shown in Figure 4. Then, the concrete 6' that is filled between the inner frame 2 and the outer frame 1 and has not yet reached #At is consolidated by the expansion pressure corresponding to the expansion amount (δ), and in conjunction with the vibration or vibration-pressure mentioned above, , becomes extremely detailed.

Next, when the concrete product is taken out from the curing equipment and cooled together with the formwork equipment personnel, the inner frame 2 will shrink back to its original state due to temperature changes as shown in Figure 5. Due to natural contraction, it is easily separated from the concrete product 61, and a gap 7 equal to the above-mentioned relative expansion amount (J) is created between the concrete product 6I' and the inner frame 2.

Therefore, the inner frame 2 does not require any complicated demolding means as in the prior art, and simple aK type molding can be performed by simply pulling it upward. Incidentally, the separation of the 10-unit outer frame from each other and the separation from the bottom plate 5 are performed in the same manner as in the conventional method.

In the round manufacturing method shown in this embodiment, the unhardened concrete 6' can be consolidated by the inner frame 2 by utilizing the expansion and contraction phenomena due to temperature changes of hard vinyl chloride material with a high coefficient of linear expansion. !i It is possible to easily demold the inner frame 2 and the concrete product 6# during the shrinkage process of the inner frame 2.

Since the tft-1 inner frame 2 uses a seamless one-piece formwork, there is no fear that a level difference will occur in the inner surface of the concrete product 6# as in the conventional case, and an extremely smooth inner surface can be obtained.

Furthermore, when pulling out the inner frame 2, the inner frame 2 has already been separated from the concrete product 6I'.

No external force acts on the concrete product 6', and the product 6
' will not be damaged.

In this embodiment, hard vinyl chloride material is used for the inner frame 2, but the material is not limited to this.
Suitable materials such as other synthetic resin materials having a high coefficient of linear expansion, such as Oka, can be used.

In addition, in this embodiment, the shape of the inner frame 2 is approximately circular in cross section.

It can be made into any shape such as an ellipse or a rectangle.

Further, the inner frame 2 may have a predetermined wall thickness and a hollow cylindrical shape, and a vibrating device such as a vibrator or a motor may be disposed inside the inner frame 2.

It should be noted that the diameter of the inner frame 2 is (1000 mm), linear expansion coefficient (gl = 7 x 10''/1:', steam curing temperature jlfl) -7011'.

If the temperature of the inner frame 2 before steam curing (t) = 20t:', then the width (δ) of the gap 7 is: J =)Dg (T-t) = ix 1000 x 7
X 10-' (70-20) -1.75m.

In the present invention configured as described above, since a seamless integral inner frame can be used, it is possible to easily assemble the formwork and obtain a good product with a smooth inner surface finish of the concrete product. I can do it.

In addition, since the inner frame is made of a material with a high coefficient of linear expansion, the expansion effect during the curing process of the inner frame can consolidate unhardened concrete and create a more compact product. Due to the shrinking action of the frame, it is possible to naturally separate from the concrete product, so there is no need for demolding.There is no problem such as damage to the concrete product or internal distortion, and the demolding work can also save a lot of labor. .

In other words, it is extremely useful because it can improve the efficiency and productivity of the entire manufacturing process and reduce the cost of the product.

[Brief explanation of the drawing]

1wA is a schematic diagram showing a conventional formwork device, FIGS. 2 to 5 show an embodiment of the formwork device according to the present invention, FIG. 2 is a schematic perspective view, and FIG. 3 is a concrete slurry injection 4 is a cross-sectional view immediately after, FIG. 4 is a cross-sectional view during steam curing, and FIG. 5 is a cross-sectional view of a good state after being cooled through the curing process. A...Formwork device, l...Outer frame, 2
...Inner frame, 5 ...Bottom plate, 6
・・・・・・Concrete slurry. Figure 1/b Procedural amendment (voluntary) I/31/1980 Commissioner of the Japan Patent Office Shima 1) Haruki Tono1, Indication of the case Showa 1987 Patent order No. 1s787 No.2, Name of the invention = / Cleat member Akira OII construction method 3, person making the amendment 6, content of the amendment Contents of the amendment as attached (1) 1J1111, page 2, line 10 @Kl:M'
Correct "Concrete Pipe 1" to "Concrete Pipe 1". (2) 8th line, 10th line of the specification, KF autoclave] should be corrected to ``steam curing device.''

Claims (3)

[Claims] (1) In a manufacturing method in which a concrete product is formed by vibration or vibration-pressure using a formwork device consisting of an inner frame and an outer frame, a material with a large coefficient of linear expansion is used as the inner frame, After the above-mentioned vibration or vibration-pressurization, a predetermined steam curing is performed, and after the curing, the inner frame is pulled out and demolded using the gap created between the inner frame and the concrete product due to the change in liJ. % mold-free concrete product manufacturing method. , ゛ ・5 (2) The above inner frame is 6 to s x lo, /c (F)
ai! A method for producing a concrete product according to claim 1, which is made of a hard vinyl chloride material having a coefficient of expansion. (3) The method for producing a concrete product according to claim 1 or 2, wherein the steam curing is carried out at a temperature of -60 to 8oC.