JPH05192911A - Centrifugal molding apparatus of pc concrete panel - Google Patents

Abstract

PURPOSE:To provide the subject molding apparatus capable of producing a PC concrete panel generating no laitance layer and excellent in compression strength in large quantity though centrifugal molding is utilized. CONSTITUTION:A large number of partition walls 2 are juxtaposed on the inner peripheral surface of a cylindrical centrigual mold 1 in the axial direction of the mold 1 and the spaces between the partition walls 2 become the centrifugal molding parts of injected concrete 4. Drain passages 3 are formed in the partition walls 2 and the drain holes 3a communicating with the drain passages 3 are provided to the contact side surfaces with injected concrete 4 of the partition walls 2 by drilling and filter plates 7 covering the drain holes 3 are arranged between the partition walls 2 and the injected concrete 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifuge molding apparatus for PC panels capable of mass-producing high-strength PC panels by a centrifuge molding method.

[0002]

2. Description of the Related Art Conventionally, a concrete panel used for sheet piles is a mechanical pressure curing method which is manufactured by compacting concrete with a vibrator and steam curing, and then demolding and performing wet curing. Or by a vacuum concrete method that uses atmospheric pressure instead of a vibrator to remove excess water with a vacuum mat and a pump, or by a pressurized vacuum method that uses a vacuum pump to remove water and the air pressure of a special mat. Currently, it is manufactured by various construction methods.

However, in the method (1), concrete is poured into a mold and the concrete is solidified, so that not only partial unevenness occurs but also the compressive strength is limited. Was not satisfied. Further, since the production method is one by one, there is a problem that the production efficiency is poor.

Therefore, the inventor installed a plurality of partition walls on the inner peripheral surface of the cylindrical centrifugal molding die in parallel to the axial direction, injecting concrete between the partition walls, and then rotating the centrifugal molding die. A PC molded along the inner circumference of a centrifugal mold to harden the poured concrete and thereby to divide and mold the partition wall.
We have developed a method of forming panels.

According to the centrifugal molding method, it is possible in principle to mass-produce uniform, dense, and high-strength PC panels, but the relationship of specific gravity to the inner peripheral surface of the concrete molded body during centrifugal molding. However, since a laitance layer with a large amount of water, low specific gravity and weak strength is generated, when using it as a pole that does not apply bending load to the inner peripheral surface, the rabbit is square, when using it as a panel, the rattans layer is When a load is applied from the layer side, there is a problem that this laitance layer becomes a weak point and the laitance layer is damaged.

[0006]

The problems to be solved by the present invention are as follows.
This is to remove the laitance layer, which has been a problem for the centrifugal molding method effective for the production of PC concrete panels.

[0007]

The centrifugal molding apparatus for a PC panel according to the present invention has been made in view of the above problems, and includes a tubular centrifugal molding die (1) and a tubular centrifugal molding die (1). A drainage hole that is erected parallel to the axial direction on the inner peripheral surface, and the space between them is the centrifugal molding part of the poured concrete (4), which communicates with the drainage channel (3) formed inside.
(3a) is provided between the partition walls (2) and the poured concrete (4), and a plurality of partition walls (2) are provided on the side surface in contact with the poured concrete (4). It is characterized by comprising a filter material (7) covering 3a).

As a result, only the water in the poured concrete is filtered by the filter medium during the centrifugal molding, and the filtered excess water flows into the drainage channel in the partition wall through the drain holes, and as a result, Water decreases and P
It was possible to remove the laitance layer, which was a problem for the centrifugal molding method effective for the production of C concrete panels.

[0009]

The present invention will be described in detail below with reference to the illustrated embodiments. FIG. 1 shows a centrifugal molding die for four divisions used in the present invention.
In the sectional view of (1), the centrifugal molding die (1) has a square cross section,
It can be divided into four from the corner. These split types
(1a) can be connected and assembled with a tightening bolt (8) screwed to a mounting rib (15). At least two disc-shaped rotating rails on the outer circumference of the centrifugal mold (1)
(9) is installed and supported by the drive roller (10).

A partition wall (2) is erected on the inner circumference of the inner corner of the centrifugal molding die (1) in parallel with the axial direction. Partition wall (2)
Has a rectangular cross section with the lower end along the inner circumference of the inside corner, and the drainage channel for discharging excess water is inside the partition wall (2).
(3) is formed over the entire length of the partition wall (2). The partition wall (2), in the present embodiment, a pair of vertical side surface portions (2b), the ceiling portion (2a) connecting the vertical side surface portions at the top and the vertical side surface portion (2b) is inclined outward from the lower part. It is composed of an inclined side surface portion (2c) extended. Further, a drainage hole (3a) communicating with the drainage channel (3) formed inside is bored on a side surface contacting the poured concrete (4). In the illustrated embodiment, the drain hole (3a) is formed in the inclined side surface portion (2c), but it is not limited to this, of course, and it may be provided in the vertical side surface portion (2b). Further, the vertical side surface (2b) is provided with a rectangular projection (2d) protruding over the entire height thereof, and as shown in FIG. It is designed to form a shear cotta (5b). Rectangular projection (2
d) is indicated by a broken line in FIG.

Reference numeral (7) is a filter material, which is disposed between the plurality of partition walls (2) and the partition walls (2) and the poured concrete (4) so as to cover the drain hole (3a). ing. The filter material (7) is
Filter cloth, filter paper and others for pouring concrete (4)
Any of those that can filter only the excess water therein can be used.

[0012] First, the top reinforcement, the bottom reinforcement, the truss reinforcement and the other reinforcements (13) are arranged between the partition walls (2), and the filtering material (7) is attached to the inclined side surface part () of the partition wall (2). Attach it to 2c) and cover the drain hole (3a). Subsequently, a predetermined amount of concrete (4) in the centrifugal molding die (1) (that is, concrete (4) during centrifugal molding)
(Slightly over the partition wall (2)), and rotate the cylindrical centrifugal mold (1) to perform centrifugal compaction. At this time, a laithance layer (6) having a large amount of water and a low specific gravity is present on the inner circumference of the poured concrete (4) {shown by a virtual line in FIG. } Is generated, but only the excess water in the injected concrete (4) is filtered by the filter material (7), and the filtered excess water flows into the drainage channel (3) through the drain hole (3a). , The water content of the entire poured concrete (4) is reduced, and the laitance layer (6) is not generated. After forming the concrete molded body in this way, it is then cured. When the curing is completed, the tightening bolt (8) is removed, the centrifugal molding die (1) is broken, and the mold is removed.
Complete the concrete panel (5). The partition wall (2)
In this case, the side surface contacting with the poured concrete (4) means the vertical side surface portion (2b) and the inclined side surface portion (2c).

The PC concrete panel (5) is formed in the shape of a lens having a concave cross section, and the reinforcing bar partially embedded therein projects from the concave surface portion (14). Further, the filter material (7) is integrally embedded in the abutment side surface portion (5c) as shown in FIG.

FIG. 3 shows an example in which a PC concrete panel (5) formed by the above-mentioned four-division centrifugal molding method is laid on a foundation beam or a wall surface to form a bottom plate of a concrete floor (18) to be cast on site. In this case, the concave part (1) of the PC concrete panel (5)
The reinforcing bar (13) protruding to 8) is embedded in the top concrete (17) that constitutes the concrete floor (18), and the two are integrated. (16) is a horizontal streak fitted to the upper end of the shear cotta (5b) of the PC concrete panel (5). By fitting the horizontal streak (16) on the upper end of the shear cotta (5b), the horizontal streak (16) can be easily positioned.

Further, regarding the formation of the concrete floor (18),
Moisture of the top concrete (17) flows down between the abutting side faces (5c) of the PC concrete panel (5), but if the gap between the abutting side faces (5c) is sufficiently narrow, the filter medium (7) will be some extent. Fulfills the filtering function of and prevents concrete dripping.

In the present embodiment, the centrifuge molding die (1) is divided into four parts, but the present invention is not limited to this and may be divided into two parts or more parts. An appropriate number of divisions is adopted according to the sizes of the molding die (1) and the concrete panel (5) to be manufactured.

The compressive strength of the PC concrete panel (5) manufactured by the centrifugal molding method as described above is much higher than that of the conventional concrete panel manufacturing method.

Since the present invention has the above-described structure,
A high-strength PC panel can be mass-produced by a centrifugal molding machine originally used for manufacturing a cylinder, and a PC without a laitance layer which has been a problem in the conventional centrifugal molding method.
It has the advantage that concrete panels can be molded.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of an embodiment of a centrifugal molding die according to the present invention.

FIG. 2 is a sectional view of an embodiment of a centrifugal molding die according to the present invention.

FIG. 3 is a drawing showing an example of use of a PC concrete panel manufactured according to the present invention.

FIG. 4 is a partial perspective view of a PC concrete panel manufactured according to the present invention.

[Explanation of symbols]

 (1)… Centrifugal mold (1a)… Split mold (2)… Partition wall (3)… Drainage channel (3a)… Drainage hole (4)… Injected concrete (5)… PC concrete panel (6)… Laitance layer (7) ... Filter material

Claims (1)

[Claims] 1. A centrifugal centrifugal molding die, and an inner peripheral surface of the cylindrical centrifugal molding die which is erected parallel to the axial direction, and a space between them is a centrifugal molding portion of the poured concrete, and a drainage channel is formed inside. It is composed of a plurality of partition walls having communicating drainage holes formed on the side surface in contact with the poured concrete, and a filter material arranged between the partition walls and the poured concrete and covering the drainage holes. Characteristic PC panel centrifugal molding equipment.