JP4006783B2 - Centrifugal formwork of half PC pillar - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a centrifugal molding form of a half-PC (precast concrete) column, and more particularly to a centrifugal molding form of a half-PC column capable of producing a half-PC column that does not require the use of a form frame for joining with a beam.
[0002]
[Prior art]
The present applicant has previously developed a mold for centrifugal molding of a tubular member made of PC disclosed in Japanese Patent No. 2609347 (Japanese Patent Laid-Open No. 4-83604). The PC cylindrical member made using this mold can be molded into a hollow rectangular cross-section while bringing concrete into close contact with the inner periphery of the mold by centrifugal force, forming a dense layer on the surface by centrifugal molding Because it can be applied to this, it can be applied to the manufacture of semi-PC pillars that make up the surface material of pillars. By using the half-PC pillars as permanent molds, reinforcing bars are built inside and filled with cast-in-place concrete. Therefore, the pillar can be constructed without the need for the subsequent form removal work.
[0003]
Conventionally, as shown in FIG. 9, the overall height H of the half PC column 56 is set to a dimension h from the floor height from the floor slab 50 to the ceiling slab 52 to the lower end of the beam 54. It was manufactured with a length obtained by subtracting the adjustment dimension d.
[0004]
Then, as shown in FIG. 10, the joint portion that joins the upper end portion of the half PC column 56 and the end portion of the beam 54 sets the end portion of the beam 54 having a smaller width than the half PC column 56 on the column 56. In the corner of the column head space that will be on both sides of the end of the beam 54, a formwork 58 that covers the column and serves as a concrete stop is installed along the column surface, and concrete is placed inside this. In this way, the column and beam joints were constructed in one piece.
[0005]
[Problems to be solved by the invention]
However, the installation work of the above-mentioned formwork 58 is troublesome, and it is a high place work, so the safety is low. In addition, the workability is lowered because the work of removing the formwork 58 must be performed after the completion of the construction. In addition, there is a drawback that the advantage in construction by using the half PC pillar 56 is reduced.
[0006]
The present invention solves the above-mentioned problems, and its purpose is to eliminate the formwork to be concrete-clamped and the work at the upper position, and to further reduce labor, and to manufacture the half-PC pillar A method is provided.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, a centrifugal molding form of a half-PC column having a cylindrical outer mold form having an internal space with a rectangular cross section and being driven to rotate around an axis portion. In order to pre-form a notch portion for engaging and mounting the end portion of the beam to be joined to the column head portion of the half-PC column manufactured by the centrifugal mold, the end portion on the column head side of the outer mold frame An insulating member that is arranged on the inner surface of the outer surface of the outer mold and faces the corners of the outer mold, and is spaced from the outer mold by a predetermined distance. An inner mold frame arranged along the shaft core portion, wherein the insulating member is disposed between the adjacent inner mold frames so as to be in contact therewith.
[0008]
Therefore, according to the centrifugal molding form of the half-PC column of the present invention, the cylindrical half-PC column manufactured by centrifugal molding has a rectangular shape and becomes a part to be engaged with the beam of the half-PC column. A notch corresponding to the beam cross section can be formed in advance at the mouth position. Therefore, by simply fitting and installing the end of the beam in the notch, it is possible to construct a column / beam joint by placing concrete inside the half PC column and beam without providing a separate formwork. As a result, it is possible to save as much labor as possible in construction work. In addition, the above-mentioned notch is formed by an extremely simple operation in which an insulating member for forming a notch that matches the beam cross section is arranged on the inner surface of the end of the outer mold on the column head side of the centrifugal mold. Since it can be performed, it can be easily applied to an existing centrifugal molding apparatus. In addition, since the insulating members are arranged in contact with each other between the adjacent inner molds, it is possible to prevent the concrete from protruding between the insulating members and the inner molds.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0010]
1 is a cross-sectional view (corresponding to the II line portion in FIG. 2) showing the main part of the centrifugal mold according to the present invention, and FIG. 2 is an arrow of the II-II line portion shown in FIG. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 1 and FIG. 4 is a perspective view showing the external appearance.
[0011]
As shown in FIGS. 1 to 4, the centrifugal mold 2 has a rectangular cylindrical outer mold 4 and a cylindrical body 6 surrounding the outer periphery of the outer mold 4, and they are The shaft cores are aligned and provided on the same axis.
[0012]
The outer mold frame 4 is formed in a cylindrical shape having an internal space having a rectangular cross section, with two congruent iron plates 8 and 8 being butted against each other. The iron plates 8 and 8 are formed with joining flanges 8a and 8a extending outwardly along the diagonal direction at both side ends, and the joining flanges 8a and 8a are overlapped to form two iron plates 8 and 8. Are fastened and detachable by bolts 10.
[0013]
The cylindrical body 6 is also formed by abutting two steel plates 12 and 12 that are formed in a semicircular shape. The flanges 12a and 12a for joining are extended radially outwardly at both ends of the semicircular iron plate 12 for the cylindrical body, and the joining flanges 12a and 12a are formed on the iron plate for the outer frame. 8 and 8 are welded to the joining flanges 8a and 8a, and the semicircular iron plates 12 and 12 for the cylindrical body are integrally joined to the iron plates 8 and 8 for the outer frame.
[0014]
A space defined between the outer mold 4 and the cylindrical body 6, that is, an outer mold iron plate 8 and a semicircular iron plate 12 for the cylindrical body which are integrally welded to each other. Between them, a reinforcing material 14 such as lightweight concrete or mortar is filled. In the illustrated example, a cavity 15 is formed in the filling layer of the reinforcing material 14 for weight reduction.
[0015]
Further, disks 16 are integrally attached to both ends of the outer mold 4 and the cylindrical body 6 surrounding the outer mold 4 so that the centers thereof coincide with the axis of the outer mold 4. In the illustrated example, a disk 16 is fitted and fixed integrally to both ends of the cylindrical body 6 via bolts 18 at both ends in the axial direction. The disk 16 also serves as end plates at both ends in the axial direction of the outer mold 4, and a concrete concrete inlet 20 is formed in a rectangular shape at the center of the disk 16. The inner peripheral side cross-sectional dimension of the end face is substantially determined.
[0016]
Further, in the outer mold frame 4, facing the four corners, the triangular mold-shaped inner mold frame 22 extends along the axial direction of the outer mold frame 4 with a predetermined distance from the outer mold frame 4. The inner mold 22 is engaged with each corner of the insertion port 20 opened at the disk 16 at both ends, and is detachably fastened with bolts via the bracket 21.
[0017]
By the way, this centrifugal mold 2 is provided with an insulating member 24 for previously forming a notch for engaging a beam, which will be described later, at the head of a column to be manufactured by this centrifugal molding. ing. The insulating member 24 is made of, for example, foamed polystyrene, and is provided by being attached to the inner surface of the column head side end portion of the outer mold frame 4. The size of the insulating member 24 is equal to the beam cross section and is formed by centrifugal molding. It has a thickness equal to or greater than the thickness of the cylindrical pillar, and is disposed between the adjacent inner molds 22 and 22 so as to be in contact therewith. That is, in this illustrated example, the distance between the adjacent inner molds 22 and 22 matches the width of the beam.
[0018]
As shown in FIG. 5, the centrifugal mold 2 configured in this way is placed so that each disk 16 straddles the driving drum 30 and the driven drum 32 of the rotation driving device 28 as shown in FIG. 5. Then, it is rotationally driven around the axis. At this time, a predetermined amount of ready-mixed concrete is charged and supplied into the internal space of the outer mold 4 from a concrete pump or the like (not shown) through the charging port 20. The driving drum 30 of the rotation driving device 28 is rotated by a motor 36 via a belt 34.
[0019]
The ready-mixed concrete put into the outer mold 4 enters the annular centrifugal molding space S defined between the inner mold 22 and the outer mold 4 by the centrifugal force, and both sides of each insulating member 24. The inside of the molding space S at the corners of the part wraps around and is filled, and excess water contained therein is discharged into the internal space while being pressed against the inner peripheral wall surface of the outer mold 4 and is gradually compacted. The concrete material, which is an advantage of centrifugal molding, is solidified into a cylindrical body with high strength and high quality. At this time, the centrifugal force acts on the outer mold 4 with a considerable magnitude. The outer mold 4 has a cylindrical body 6 that surrounds the outer peripheral side thereof, and the cylindrical body 6 and the outer mold frame 4. The strength and rigidity are enhanced by the reinforcing material 14 filled between the outer mold frame 4 and the outer mold frame 4 does not swell radially outward by centrifugal force.
[0020]
Then, after the concrete is hardened, the centrifugal molding form 2 is disassembled and removed to obtain a half-PC column. FIGS. 6A and 6B show a joining structure of the half PC column 40 manufactured by the centrifugal molding and the PC beam 42 joined to the head of the half PC column 40. FIG. As shown in FIG. 5A, the half PC column 40 has a rectangular hollow cylindrical shape with a predetermined thickness, and a rectangular cut portion on which the half PC beam 42 is engaged and placed on the column head. A notch 44 is formed, and its total height H is formed to be a dimension obtained by subtracting the installation dimension d from the floor height between the floor 50 and the ceiling slab 52 as shown in FIG.
[0021]
Here, four U-shaped half PC beams 42 intersect the cross shape of the half PC column 40, and correspondingly, the half PC column 40 has four cuts corresponding to the beam cross section of the half PC beam 12. A notch 44 is formed in each surface of the half-PC pillar 40, and each PC beam 42 is supported by fitting its end into each notch 44, as shown in FIG. 6B. .
[0022]
Accordingly, in this state, a number of beam main bars (not shown) are vertically built inside the half PC column 40, and a beam main bar (not shown) is arranged inside the half PC beam 42, and then the inside of the column 40 and each beam 42 are arranged. By simply placing concrete inside the column, the column-beam joint can be formed integrally, and the subsequent mold removal work is completely unnecessary.
[0023]
In addition, since both ends of each half PC beam 42 are supported in the notch 44 of the half PC column 40, positioning work at the time of installation of a support for supporting the intermediate portion of the PC beam 42 thereafter is also simple. It becomes.
[0024]
FIGS. 8A to 8C show an example of changing the connection shape in FIG. 6. In FIG. 8A, three notches 44 are each formed in a T-shape at the column head of the half-PC column 40, and three openings are formed. In the case, (b) shows a case where two are formed to face each other by 180 °, and (c) shows a case where two are formed at an orthogonal angle of 90 °, and it is of course possible to adapt to any joining form. .
[0025]
The notches 44 in FIGS. 6 and 8 are formed in the centrifugal mold 2 as described above, and the insulating member 24 having the same shape as the notches 44 is formed in the portion corresponding to the joint position of the outer mold 4. Since the concrete is filled into the centrifugal molding space S with this portion removed by simply attaching it to the inside and the like, the half PC pillar 40 having the notch 44 having the shape shown in each figure is provided. It can be easily formed, and is suitable when the cross section of the beam connected to the column is known and has a constant cross section. In addition, this method can be easily implemented because it is only necessary to add the insulating member 24 to the existing centrifugal mold 4.
[0026]
When the half PC column 40 is very thin and can be easily cut by a concrete cutter or the like, a square tube in which the half PC column 40 is first subtracted from the floor height by the installation dimension d is formed. Then, the notch 44 is cut into a rectangular shape in accordance with the cross-sectional shape of the beam 42 to be joined thereto, so that the column-beam connection can be made in the same joining form as described above.
[0027]
【The invention's effect】
As is clear from the above description, according to the centrifugal molding form of the half PC column of the present invention, the cylindrical half PC column having a rectangular cross section manufactured by centrifugal molding has a beam of the half PC column. A notch that coincides with the cross section of the beam can be formed in advance at a joint position that becomes a joint portion. Therefore, by simply fitting and installing the end of the beam in the notch, it is possible to construct a column / beam joint by placing concrete inside the half PC column and beam without providing a separate formwork. As a result, construction is simplified and labor saving of construction work is possible.
[0028]
In addition, since both ends of the beam are positioned and supported by the cutouts of the half PC pillar, there is an advantage that the arrangement and positioning of the beam support are simplified.
[0029]
Further, the notch is formed by an extremely simple operation by simply placing an insulating member for forming a notch that matches the beam cross section on the inner surface of the end of the outer mold on the column head side of the centrifugal mold. Since it can be performed, it can be easily applied to existing centrifugal molds. In addition, since the insulating members are arranged in contact with each other between the adjacent inner molds, it is possible to prevent the concrete from protruding between the insulating members and the inner molds.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a cross section of a main part of a centrifugal mold according to the present invention, as seen from the direction of an arrow II in FIG.
FIG. 2 is a cross-sectional view taken along the line II-II in FIG.
3 is a cross-sectional view taken along the line III-III in FIG.
4 is a perspective view schematically showing an external appearance of the centrifugal mold in FIG. 1. FIG.
FIG. 5 is a diagram illustrating a state in which a centrifugal mold is placed on a rotation drive device.
FIGS. 6A and 6B are views showing a joint structure of a half PC column manufactured by the centrifugal mold and a beam joined to the half PC column.
FIG. 7 is a side view showing the installation dimensions of the half PC column.
8A to 8C are views showing a connection shape change example of FIG.
FIG. 9 is a side view showing the installation dimensions of a conventional half-PC column.
FIG. 10 is a view showing a joint structure at a joint portion between a conventional half-PC column and a beam.
[Explanation of symbols]
2 Centrifugal Forming 4 Outer Form 16 Disc 20 Slot 22 Inner Form 24 Insulating Member 40 Half PC Column 42 PC Beam 44 Notch S Centrifugal Forming Space

Claims (1)

In a centrifugal molding form of a half PC column having a cylindrical outer mold form that has a rectangular internal space and is driven to rotate about an axial core part,
In order to pre-form a notch for engaging and mounting the end of the beam to be joined to the column head of the half-PC column manufactured by the centrifugal mold, the inner surface of the column head side end of the outer mold An insulating member arranged in the same shape as the cross-sectional shape of the beam;
Each facing the corner portion of the outer mold frame, an inner mold frame disposed along the axial core portion of the outer mold frame at a predetermined interval from the outer mold frame,
With
The half-PC column centrifugal mold form , wherein the insulating member is disposed between the adjacent inner mold forms in contact with each other .

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