JP3979683B2 - Precast concrete formwork - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a precast concrete formwork (hereinafter referred to as PCa formwork ) .
[0002]
[Prior art]
In recent years, PCa formwork has come to be used in civil engineering concrete work. The PCa formwork has many advantages over the wooden formwork, including (a) labor saving in construction, (b) shortening the construction period, (c) improving durability, and (d) protecting the global environment.
In order to evaluate the PCa formwork as part of the frame concrete structure, the PCa formwork needs to be sufficiently integrated with the post-cast concrete. For this reason, as a method of ensuring the integration of the two, as shown in FIG. 8 (a), unevenness c is provided on the back surface of the mold frame a on the surface of the PCa mold frame in contact with the post-cast concrete b. As shown in FIG. 8 (D), a die surface d is embedded in the PCa mold a, and a rough surface e is provided on the back surface of the PCa mold a as shown in FIG. For example, a rib 1 is integrally provided on the rear surface of the frame, and a cotter 1 'is embedded in the rear surface of the mold as shown in FIG. PCa formwork is generally manufactured by steel formwork as a factory product. Since steel formwork is used in this way, it takes a lot of time to arbitrarily change the shape and position of irregularities. And spend with effort. In addition, by providing irregularities on the back surface of the PCa mold and embedding the dowel stripes, the steel mold itself has a complicated structure, and much time is spent in assembling and demolding the steel mold. In addition, reinforcing bars are generally used as the gibber bars, and corrosion of the reinforcing bars may become a problem depending on the concrete cover thickness.
[0003]
[Problems to be solved by the invention]
In particular, if the mold back Ru provided wedge ribs together, as shown in FIG. 9 (b), PCa Manufacturing and steel mold at the same time frame body f body integrally with the steel mold g It was manufactured using. In the figure, h is a reinforcing bar. FIG. 9B shows the completed ribbed PCa formwork a. In such a manufacturing method, since the rib shape and the arrangement position of the ribs are once determined, it takes a lot of time and labor to change them.
[0004]
On the other hand, the PCa formwork must be prevented from cracking due to the side pressure when the post-cast concrete is placed. Therefore, conventionally, it is possible to increase the thickness of the PCa formwork or shorten the fulcrum interval by using a separator or a support. However, increasing the thickness of the PCa formwork is not preferable because it increases the weight of the PCa formwork and the need to increase the size of the lifting machine arises.
[0005]
The present invention has been proposed in view of such problems, the purpose of which is to ensure the integrity of the PCa formwork and post-cast concrete, and to improve the rigidity of the PCa formwork itself, And it exists in the point which simplifies the manufacturing method of the PCa formwork with a rib.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a precast concrete formwork according to the present invention is formed by providing a narrowed portion extending in the longitudinal direction of the bowl-shaped piece on the side surface of the bowl-shaped piece manufactured prior to molding of the mold body. The wedge-shaped rib is incorporated into a mold for manufacturing a precast concrete mold, and only one portion of the wedge-shaped rib with the narrowed portion as a boundary is embedded in the concrete, and the other portion projects outside the concrete. and so, by pouring the molding concrete of the formwork body, Yes and integrating the molding concrete of the mold body and the wedge-shaped ribs, the precast concrete formwork, its shape, a rectangular plate, the precast concrete formwork is provided with the wedge-shaped rib a plurality of said wedge-shaped rib of the plurality present, each said precast co So as to extend parallel to the rectangular longitudinal sides or lateral sides of the cleat formwork, it is characterized in that it is assembled in a lattice pattern.
In addition, the precast concrete mold according to the present invention is manufactured prior to the molding of the mold body, wedge-shaped ribs configured by providing a narrowed portion extending in the longitudinal direction of the bowl-shaped piece on the side surface of the bowl-shaped piece , a polygonal tube or cylinder of the cylinder in the height direction intermediate wedge is formed by providing a constriction extending in the circumferential direction of the cylindrical body to the portion cotter, incorporated in a mold of the precast concrete formwork for the production, the wedge Only one part of the rib with the narrowed part as a boundary is embedded in the concrete and the other part protrudes outside the concrete, and only one part of the wedge-shaped cotter with the narrowed part as the boundary is the other part is embedded in the concrete so as to protrude to the outside of the concrete, by pouring the molding concrete of the formwork body, said wedge-shaped ribs and the wedge-shaped cotter Yes by integrating the molding concrete of the serial-type frame body, the precast concrete formwork, its shape is a rectangular plate, the precast concrete formwork, comprises the wedge-shaped rib a plurality of The plurality of wedge-shaped ribs are assembled in a lattice shape so that each of the wedge-shaped ribs extends in parallel to the rectangular vertical side or horizontal side of the precast concrete formwork. The concrete formwork is provided with a plurality of the wedge-shaped cotters, and the plurality of wedge-shaped cotters are arranged at least at each corner of the rectangle of the precast concrete formwork. .
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described with reference to the drawings.
As shown in FIG. 1 (a), a wedge-shaped rib 1 or a wedge-shaped cotter is manufactured by a steel mold and extrusion molding. The wedge-shaped rib 1 is provided with a narrowed portion extending in the rib longitudinal direction in the middle of the height direction of both side surfaces.
[0008]
Next, as shown in FIG. 1 (b), a mold frame 2 for manufacturing a PCa mold is manufactured, a reinforcing bar 3 is arranged in the same mold frame 2, and then, as shown in FIG. The rib 1 and / or the wedge-shaped cotter described later are arranged on the assembled mold 2. The wedge-shaped rib 1 or cotter is disposed at a position that increases the rigidity of the PCa mold body and improves the integrity of the PCa mold and the post-cast concrete. Next , with respect to the wedge-shaped rib 1, only one portion with the above-described narrowed portion as a boundary is embedded in the concrete and the other portion protrudes to the outside of the concrete. Place the concrete 4 of the PCa formwork body so that only one part is embedded in the concrete and the other part protrudes outside the concrete (see Fig. 1 (D)). After the concrete 4 exhibits a predetermined strength, it is removed from the mold and the PCa mold 5 is formed. (See FIG. 2) In the figure, 1 'is a wedge-shaped cotter.
As shown in FIG. 2, PCa mold 5, the shape, rectangular plate der is, that have a side edge of the vertical and horizontal. Furthermore, PCa mold 5 is provided with a wedge-shaped rib 1 a plurality of, those plurality of wedge-shaped rib 1, each of which extends parallel to the longitudinal sides or lateral sides of PCa mold 5 Thus, it is assembled in a lattice shape . Further, the PCa mold 5 is provided with a plurality of wedge-shaped cotters 1 ′, and the plurality of wedge-shaped cotters 1 ′ are disposed at least in the corners of the rectangle of the PCa mold 5.
[0009]
FIG. 3 shows an example of construction using the PCa formwork 5. The PCa formwork 5 with wedge-shaped ribs 1 is set at a predetermined position using a lifting machine and fixed by a support 6, and then the PCa formwork 5 is used. Then, the existing concrete 7 is sprinkled with water, and then the post-cast concrete 8 is placed. (See Figure 3)
4 (a) and 4 (b) show the difference in the arrangement state of the support 6 depending on the presence or absence of the wedge-shaped rib, and the PCa formwork 5 on which the wedge-shaped rib 1 is arranged is a conventional PCa without the rib. The number of supporters 6 that support the formwork is reduced compared to the formwork.
[0010]
Note 5 (b) shows the actual施例of wedge ribs 1, FIG. 5 (b) and (c) shows an embodiment of the wedge-shaped cotter. Figure 5 wedge rib 1 (a) is as described above, on both sides in the height direction of the rod-shaped pieces of rectangular cross-section, constriction extending in the longitudinal direction of the rod member is provided, wedge-shaped in FIG. 5 (b) Cotter 1 'in the height direction intermediate cylindrical body, constriction extending in the circumferential direction is provided, wedge-shaped cotter 1 in FIG. 5 (c)' to the height direction intermediate prism, stenosis is over the circumferential direction The case where it is provided is shown.
6A, 6B, 6C, and 6D show various cross-sectional shapes of wedge-shaped ribs. 7 shows various materials of the wedge-shaped rib, FIG. 7 (a) shows the case where the H steel 10 is embedded in the concrete body, FIG. 7 (b) shows the case where the reinforcing bar 11 is embedded in the concrete body, FIG. 7 (c) shows the case where the wedge-shaped rib is formed of the steel box 12, and FIG. 7 (d) shows the case where the steel box 12 is filled with H steel 10 and concrete 13. FIG.
[0011]
FIG. 7 (e) shows the case where the H steel 10 is embedded in the resin 14 body, FIG. 7 (f) shows the case where the reinforcing bar 11 is embedded in the resin 14, and FIG. 7 (g) shows the entire wedge-shaped rib 1 being a hard resin. 7 shows a case where the concrete 13 and the reinforcing bar 11 are built in the steel box 12.
[0012]
【The invention's effect】
As described above, according to the first aspect of the present invention, the wedge-shaped rib produced prior to the molding of the PCa mold body is incorporated into the mold for producing the PCa mold, and one of the wedge-shaped ribs is used as a boundary. By placing the concrete for molding of the PCa formwork body so that only the part is embedded in the concrete and the other part protrudes outside the concrete , the wedge-shaped rib is fixed on the surface of the PCa formwork. a post-deposited concrete through the wedge-shaped rib is Da設in PCa mold isomorphic frame is integrated.
[0013]
Further, the wedge-shaped rib is manufactured independently of the manufacture of the PCa mold, so that the PCa mold with the complex-shaped ribs is easily manufactured.
According to the second aspect of the present invention, the wedge-shaped rib and the wedge-shaped cotter manufactured prior to the molding of the PCa mold body are incorporated into the mold for producing the PCa mold , and one part with the narrowed portion of the wedge-shaped rib as a boundary. Only one part is embedded in the concrete and the other part protrudes outside the concrete, and only one part of the wedge-shaped cotter is embedded in the concrete and the other part is outside the concrete. By projecting the molding concrete of the PCa formwork body so as to protrude , the wedge-shaped rib and the wedge-shaped cotter are fixed on the surface of the PCa formwork, and the same shape as the PCa formwork through the wedge-shaped rib and the wedge-shaped cotter. Post-cast concrete placed in the frame is integrated.
[0014]
The wedge Li blanking concrete according to the invention of claim 3, steel box, which is configured of a resin, can be manufactured with high rigidity Li blanking. Furthermore, according to the invention of claim 4, since it is molded by mold molding or extrusion molding, it is easy to manufacture.
Furthermore the wedge Li Bed According to the invention of claim 5 is concrete, reinforcing steel, mold steel, or because it is reinforced with fibers, it is possible to increase the rigidity, can be greater than the strength of PCa formwork body .
[Brief description of the drawings]
FIGS. 1A, 1B, 1C, and 1D are perspective views showing manufacturing steps of a method for manufacturing a PCa mold according to the present invention.
FIG. 2 is a perspective view of a PCa mold according to the present invention.
FIG. 3 is a longitudinal sectional view showing a usage state of the PCa mold according to the present invention.
FIGS. 4A and 4B are perspective views showing a conventional ribless PCa mold and a ribbed PC mold according to the present invention and a supporting work thereof, respectively.
FIGS. 5A and 5B are perspective views showing respective embodiments of a wedge-shaped rib and a wedge-shaped cotter, respectively.
6 (a), (b), (c) and (d) are cross-sectional views of various wedge-shaped ribs.
7A and 7B are cross-sectional views showing materials for various wedge-shaped ribs.
8 (a), (b), (c), and (d) (e) are vertical cross-sectional views showing a back surface processing portion of a conventional PCa mold, respectively.
FIGS. 9A and 9B are perspective views showing a manufacturing process of a conventional ribbed PCa mold. FIGS.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Wedge-shaped rib 1 'Wedge-shaped cotter 2 Formwork for PCa formwork manufacture 3 Reinforcement 4 Concrete 5 PCa formwork 6 Support 7 Existing concrete 8 Post-cast concrete 9 Type steel 10 H steel 11 Reinforcement 12 Steel box 13 Concrete 14 Resin 15 Hard resin

Claims (5)

In precast concrete formwork,
A wedge-shaped rib, which is manufactured prior to the molding of the mold body and is provided with a narrowed portion extending in the longitudinal direction of the bowl-shaped piece on the side surface of the bowl-shaped piece, is incorporated into a mold for manufacturing a precast concrete mold. By placing the concrete for molding of the mold body so that only one part of the wedge-shaped rib bordering on the narrowed part is embedded in the concrete and the other part protrudes outside the concrete. , Yes and integrating the molding concrete of the mold body and the wedge rib,
The precast concrete formwork has a rectangular plate shape,
The precast concrete formwork is provided with a plurality of the wedge-shaped ribs, and each of the plurality of wedge-shaped ribs extends in parallel to a rectangular vertical side or a horizontal side of the precast concrete formwork. As it exists, it is assembled in a grid ,
Precast concrete formwork characterized by that. In precast concrete formwork,
A wedge-shaped rib that is manufactured prior to the molding of the mold body and is provided with a narrowed portion extending in the longitudinal direction of the bowl-shaped piece on the side surface of the bowl-shaped piece, and the middle of the polygonal cylinder or cylindrical cylinder in the height direction a circumferential constriction extending constructed by providing a wedge-shaped cotter of the cylindrical body in part by incorporating a mold for precast concrete formwork fabrication, one portion of the boundary of the narrowed portion of the wedge-shaped ribs Only one part is embedded in the concrete and the other part protrudes outside the concrete, and only one part of the wedge-shaped cotter is embedded in the concrete and the other part is the outside of the concrete. so as to project into the molding concrete of the formwork body by pouring, there are integrated the molding concrete of the mold body and the wedge-shaped ribs and the wedge-shaped cotter
The precast concrete formwork has a rectangular plate shape,
The precast concrete formwork is provided with a plurality of the wedge-shaped ribs, and each of the plurality of wedge-shaped ribs extends in parallel to a rectangular vertical side or a horizontal side of the precast concrete formwork. As it exists , it is assembled in a grid ,
The precast concrete formwork is provided with a plurality of the wedge-shaped cotters, and the plurality of wedge-shaped cotters are disposed at each corner of the rectangle of the precast concrete formwork,
Precast concrete formwork characterized by that.   The precast concrete formwork according to claim 1 or 2, wherein the wedge-shaped rib is made of concrete, a steel box, or a resin. The precast concrete mold according to claim 3, wherein the wedge-shaped rib is molded by molding or extrusion molding .   The precast concrete formwork according to claim 3, wherein the wedge-shaped rib is reinforced with a reinforcing bar, a steel plate, or a fiber.

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