JPH04211905A - Bendable pc concrete shuttering and its manufacture - Google Patents

Abstract

PURPOSE:To provide a bendable PC concrete shuttering which can be manufactured easily and in a short time without generating dispersion in product qualities even if the PC concrete shuttering is thin or thick one, stored and transported in large quantities even in a narrow space and used easily also at a building site and a manufacturing method of the same. CONSTITUTION:A barlike temporary member 5 is set up beforehand within a horizontal sheetlike concrete shuttering at appropriate intervals and a net 6 is arranged also. Then concrete 3 is placed within the horizontal sheetlike concrete shuttering. When the above-mentioned barlike temporary member 5 and horizontal sheetlike concrete shuttering is demoled after drying and curing of the concrete 3, a flat platelike PC concrete shuttering 1 having a notch 51 in a place where the above-mentioned barlike temporary member 5 has been in existence and has the built-in net 6 is manufactured.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a bendable PC formwork and a method for manufacturing the same, and in particular, it has stable quality, short manufacturing time, and can be stored and transported in large quantities in a narrow space. The present invention also relates to the above-mentioned PC formwork, which is easy to use at construction sites, and a method for manufacturing the same.

0002

[Prior Art] Conventionally, concrete is poured into beams, columns, etc. after constructing a steel frame or reinforcing bars for the beam or column, attaching a formwork plate around the steel frame, etc., and placing concrete inside the formwork plate. This was done by pouring concrete into the ground.

[0003] However, such construction methods require installation of formwork plates and removal work after the concrete has dried and hardened. Particularly, the installation and removal of the formwork plates at locations where the work environment is poor, such as corner beams and columns, is complicated and takes a long time.

[0004] Therefore, in recent years, in order to omit the work of attaching and removing the above-mentioned formwork plates, for example, a U-shape as shown in FIGS. 6(A) and 6(B), etc. A precast concrete formwork 01 is manufactured in advance in a factory or the like (hereinafter, this formwork is referred to as a PC formwork), and this PC formwork 01 is attached to a predetermined beam or column, etc., and the PC formwork 01
A construction method for pouring concrete inside has been developed and put into practical use.

[0005] According to this construction method, the PC formwork 01 itself becomes a component of the outer periphery of beams, columns, etc., so after pouring concrete into the PC formwork 01, work such as removing the PC formwork 01 is required. This simplifies the work and significantly shortens the construction period.

[0006]

[Problems to be Solved by the Invention] However, the conventional method for manufacturing the PC formwork 01 has the following problems. That is, in the PC formwork 01 shown in FIG. 6(A), first, concrete 03a is poured on the formwork plate 02a which will become the bottom surface of the U-shape, and after the concrete 03a hardens, the concrete 03a will become the side surface of the U-shape 4. It was manufactured by assembling two formwork plates 02b, pouring concrete 03b between the four formwork plates 02b, and finally removing the formwork plates 02a and 02b.

[0007] According to this manufacturing method, concrete 03a for the U-shaped bottom is poured, and after hardening, concrete 03b for the U-shaped sides is poured. , it is accompanied by the trouble of pouring concrete twice. Furthermore, in the mix of concrete for the sides, the water-cement ratio must be increased due to workability, which deteriorates the quality of the concrete. Therefore, the quality of the products varies, the yield is poor, and manufacturing costs rise. In addition, it is necessary to wait for the concrete 03a to harden before assembling the formwork 02b and pouring the concrete 03b, which increases the manufacturing time.

[0008] Furthermore, the PC formwork 01 shown in FIG. 6(B) is
First, a U-shape is framed with six formwork plates 02, then concrete 03 is integrally poured between these six formwork plates 02, and finally the formwork plates 02a and 02b are removed. was manufacturing.

[0009] In this manufacturing method, a concrete pouring part 04 like the PC formwork 01 shown in FIG. 6(A) above is used.
There is no need to wait for concrete 03 to harden before pouring the next concrete. However, it is not easy to pour concrete into the rising part α of the U-shape, and sometimes the concrete does not wrap around the α part, resulting in poor yields and a rise in manufacturing costs.

In particular, when manufacturing a thin U-shaped PC formwork 01, not only the above-mentioned defects are likely to occur at the rising portion α, but also the defects occur when removing the formwork plate 02 (that is, demolding). Occasionally, damage accidents occurred. Furthermore, it was inconvenient when changing the size of the PC formwork or when installing a through sleeve at the rising part.

[0011]Furthermore, both the thin and thick PC formworks 01 require a vast space for storage and transportation, and are bulky, resulting in high storage and transportation costs.

The present invention has been made in view of the above points, and its purpose is to easily and quickly process products without causing variations in product quality, even if they are thin or thick. To provide a bendable PC formwork that can be manufactured in a short amount of time, can be stored and transported in large quantities even in a narrow space, and can be easily used at construction sites, and a method for manufacturing the same. .

[0013]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a notch that is linear and has a V-shaped cross section on one side of a PC board, and at least a portion that is thinned by the notch. It is characterized by a buried net.

The present invention is also characterized in that an adhesive is filled between the opposing surfaces of the cutout of the PC board that is bent by bringing the opposing surfaces of the cutout of the V-shaped cross section into contact with each other. do.

Furthermore, in the manufacturing method of the present invention, bar-shaped temporary members are set at appropriate intervals in a horizontal plate-like form, a net is placed, and then concrete is poured into the horizontal plate-like form. After the concrete is poured and hardened, the bar-shaped temporary member and the horizontal plate-shaped formwork are removed from the mold.

[0016]

[Operation] In the manufacturing method according to the present invention, bar-shaped temporary members (for example, facing boards, other suitable joint bars) are set in advance at appropriate intervals in a horizontal plate-shaped formwork, and a net is also set. Deploy. After this, concrete is poured into the horizontal plate formwork. After this concrete has dried and hardened, the above-mentioned bar-shaped temporary member and horizontal plate-like formwork are removed from the mold, and when the above-mentioned bar-shaped temporary member was present, there is a notch, and the above-mentioned PC formwork A flat PC formwork with embedded mesh is manufactured.

[0017] This PC formwork can be bent at the above-mentioned notch. In other words, the cutout has a small cross-sectional area and easily bends, causing cracks in some parts of the concrete and causing some peeling, but due to the presence of the net, that part remains intact and becomes a hinge.

[0018] Such bendable PC molds are manufactured in advance in large quantities at a factory or the like, and stored in a stacked manner in the form of flat plates. Then, the required number of flat plates are transported to a construction site, etc., and are bent at the cutout portions according to the shape of the required beam or column, and fixed to form a formwork for the beam or column.

In particular, if an adhesive is filled between the opposing surfaces of the notches that come into contact with each other when the PC formwork is bent, the hardening of this adhesive will cause the molds that sandwich the notches to The mutual integrity of the frame pieces can be improved, and the structural strength can be increased. Furthermore, as mentioned above, even if it is assumed that some of the concrete may crack or some flaking may occur in the notched area, filling the adhesive between the facing surfaces of the notch in this way is not necessary. This makes it possible to deal with the cracks and peeling mentioned above.

[0020] Concrete is then poured into the formwork. When the concrete dries and hardens, beams, columns, etc. using the PC formwork as the outer peripheral material are completed without removing the above-mentioned PC formwork.

[0021] On the other hand, in the above explanation, the case has been described in which the PC formwork is delivered to the site as a flat plate, but if necessary, the present PC formwork may be bent in advance at a factory etc.
The PC formwork may be delivered to the site in a bent state. Particularly in this case, if you fill the notch with adhesive and let it harden, the PC formwork will expand and be damaged when transported to the site, and to prevent this, the PC formwork may be It is possible to save the effort of maintaining the shape using a special jig, etc., and to ensure strength during transportation.

[0022]

[Embodiment] Fig. 1 shows an embodiment of the manufacturing method according to the present invention in a state immediately after concrete is poured, and in this example, a face wood 5 is used as a bar-shaped temporary member. As shown in the figure, first, formwork plates 2 are combined to form a horizontal plate-like formwork, and within this formwork a desired interval (i.e., an interval according to the dimensions of beams, columns, etc., in this example) is formed. Then, a predetermined number (in this example, two) of planks 5 are set in parallel at intervals corresponding to the width of the beams.

This face wood 5 was provided in contact with the bottom of the horizontal plate-like formwork, but after setting the net 6, which will be described later, as shown in FIG.
You can also set it in an inverted triangle by hanging it over a formwork or floating it on top.

[0024] Also, a net 6 is arranged to serve as reinforcing bars for the PC formwork. This mesh 6 may be a wire mesh, but it can be used to prevent rust from occurring due to insufficient concrete cover thickness.
In particular, in order to ensure good bendability during bending, aramid fibers, vinylon fibers, carbon fibers,
It is preferable to use a fiber material such as glass fiber. When arranging it in a double mesh as shown in the figure, the upper part of the horizontal plate-shaped formwork should be placed on the entire surface, and the lower part should be placed with 5 facing pieces.
Place it except for the part. Therefore, the part where the face tree 5 exists becomes a single mesh only in the upper part, and the part where the face tree 5 does not exist becomes a double mesh in the upper and lower parts. If the entire surface is to be made into a single mesh, it is arranged in a wavy manner so that the mesh 5 is biased towards the upper part and the middle part is at an intermediate height.

[0025] After such work, concrete 3 is poured into the horizontal plate-like formwork, and once the concrete 3 has dried and hardened, the face wood 5 and the horizontal plate-like formwork are removed from the mold. . Then, a flat PC formwork 1 made of one sheet of flat concrete 3 having a cutout 51 in the area where the two face pieces 5 were present is completed. This flat PC formwork 1 allows the concrete plate 3 to be easily bent at the notch 51.

FIGS. 3 and 4 show how the bendable PC formwork 1 manufactured as described above is used. In either case, the concrete plate 3 is bent at two notches 51, and the concrete plates 32 and 33 on both sides are made at right angles to the concrete plate 31 sandwiched between the two notches 51, and approximately U Shape. The usage pattern shown in FIG.
The opposing surfaces of the concrete plates 32 and 33 are opened so as to be spaced apart from each other, and the distance between the concrete plates 32 and 33 can be widened.

On the other hand, the usage pattern shown in FIG. 4 is one in which the opposing surfaces of the notches 51 are closed so as to approach each other and come into contact with each other, so that the mutual spacing between the concrete plates 32 and 33 can be narrowed. It is.

In particular, in the usage mode shown in FIG. 4, as shown in FIG. 5, the adhesive 7 is filled between the opposing surfaces of the notches 51 that come into contact with each other when the PC formwork 1 is bent. If so, by curing of the adhesive 7, the mutual integrity of the concrete plates 31 to 33 sandwiching the notch 51 can be improved, and the structural strength can be increased. Moreover, as mentioned above, even if it is assumed that some cracks will occur in the concrete at the notch 51 part and some peeling will occur, the adhesive 7 can be applied between the facing surfaces of the notch 51 in this way. By filling, it is possible to deal with the above-mentioned cracks and peeling.

The PC formwork 1 may be delivered to the site in its flat form, but if necessary, the PC formwork 1 may be bent in advance at a factory or the like. It is also possible to transport it to the site in the same condition. Especially in this case, the adhesive 7
If it is filled into the notch 51 and allowed to harden, the PC formwork 1 will be expanded and damaged during transportation to the site, and in order to prevent this, the PC formwork 1 may be placed in a special jig, etc. This saves the effort of maintaining the shape, and also ensures strength during transportation.

Although this U-shaped thing is not shown,
A beam formwork is formed by attaching it to a beam, column, etc. (in this example, a beam) and fixing it with reinforcing material (shoring). Concrete is then poured into this beam formwork. When this concrete dries and hardens, it will be integrated with the beam formwork mentioned above, and the above P
A beam is constructed using the C formwork 1 as the outer peripheral material.

[0031] If three, four, etc. of the above-mentioned face pieces 5 are used, the PC formwork 1 having three, four, etc. notches 51 can be obtained.
This PC formwork 1 has a rectangular shape, 5
It can be used as formwork for concrete pouring of square-shaped beams and columns.

[0032]

[Effects of the Invention] As detailed above, according to the manufacturing method of the present invention, there is no pouring of concrete, so the pouring process can be completed in one step, and the concrete is placed on a horizontal form plate. Because it is a so-called flat casting method, demolding is easy, and thick to thin PC molds can be produced extremely easily and in a short time.

[0033] Furthermore, since the concrete is placed by pouring in the field as described above, the concrete can be hard-mixed, and therefore no bleed water is generated which adversely affects the quality of the concrete. In addition, concrete can be placed uniformly without the risk of creating jitters or the like. As a result, according to the manufacturing method according to the present invention,
Stable and high-quality PC formwork can be manufactured, yields can be improved, and manufacturing costs can be significantly reduced.

[0034] Furthermore, the PC formwork according to the present invention can be transported in its flat form, and a large amount of PC formwork can be stored and transported in a narrow space, and storage and transportation costs can be greatly reduced. Decrease.

Moreover, the PC formwork according to the present invention can be easily bent and is extremely easy to use on site.

Furthermore, if an adhesive is filled between the opposing surfaces of the notches that come into contact with each other when the PC formwork is bent, the hardening of this adhesive will cause the formwork sandwiching the notches to The mutual integrity of the pieces can be improved, and the structural strength can be increased. Furthermore, as mentioned above, even if it is assumed that some of the concrete may crack or some flaking may occur in the notched area, filling the adhesive between the facing surfaces of the notch in this way is not necessary. This makes it possible to deal with the cracks and peeling mentioned above.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the manufacturing method according to the present invention.

FIG. 2 is a diagram showing another example.

FIG. 3 is a diagram for explaining how the PC formwork according to the present invention is used.

FIG. 4 is a diagram for explaining another usage mode of the PC formwork according to the present invention.

FIG. 5 is a diagram for explaining how a PC formwork using adhesive is used.

FIG. 6 is a diagram illustrating a conventional method for manufacturing a PC formwork.

[Explanation of symbols]

1 PC formwork
2 Formwork board 3 Concrete
5 Rod-shaped temporary member 7
glue

Claims (3)

[Claims] [Claim 1] A bendable PC board, characterized in that a notch is provided on one side of the PC board in a straight line and has a V-shaped cross section, and a net is embedded at least in the thinner part due to the notch. PC formwork. 2. A claim characterized in that an adhesive is filled between the opposing surfaces of the cutout of the PC board, which is bent by bringing the opposing surfaces of the cutout of the V-shaped cross section into contact with each other. The bendable PC formwork according to item 1. 3. Temporary rod-shaped members are set at appropriate intervals in a horizontal plate-shaped form, and a net is placed, and then concrete is poured into the horizontal plate-shaped form, and the concrete is poured into the horizontal plate-shaped form. A method for manufacturing a bendable PC formwork, which comprises removing the rod-shaped temporary member and the horizontal plate-like formwork after the material has hardened.