JP2023177007A - Form for loading opening, and formation method for loading opening using the same - Google Patents

Abstract

To provide a form for a loading opening which facilitates position adjustment of an insertion hole of a slab reinforcement and removal after solidification of concrete, and can be inexpensively manufactured, and a formation method for a loading opening using the same.SOLUTION: A form 1 for a loading opening includes: a form body 2 which is composed of a pair of divided bodies 7 and 7 having the same shape and has a box shape whose upper part is opened; receivers 3 and column fixtures 4 which are installed at four corners of an upper end (opening end) of the form body 2; two pairs of crosspieces 5a and 5a and 5b and 5b which are arranged so as to be formed in a rectangular shape in a planar view and whose both ends are held by the receiver 3; a pair of parallel crosspieces 5c and 5d which are bridged between the pair of crosspieces 5a and 5a arranged in parallel with each other; and four columns 6 which are mounted on the four column fixtures 4 one by one.SELECTED DRAWING: Figure 1

Description

The present invention relates to a formwork used when constructing a floor plate of a reinforced concrete structure (hereinafter referred to as a "concrete slab") in a building using reinforced concrete or steel-framed reinforced concrete as a structural material. The present invention relates to a mold for forming a shipping opening (hereinafter referred to as a shipping opening) and a method of forming a shipping opening using the mold.

In buildings whose structural materials are reinforced concrete or steel-frame reinforced concrete, construction materials and tools are usually loaded and unloaded using loading openings formed in concrete slabs that make up floors, ceilings, etc.
Conventional shipping openings have been formed by a formwork made of a plurality of plywood boards installed so as to surround the area where the opening is planned to be formed. However, it took time to install wooden formwork because it was difficult to form holes in the correct positions for the slab reinforcements to pass through. Further, it is not easy to remove the formwork into which the slab reinforcements are fitted after the concrete has solidified, and there is a problem that the formwork cannot be removed efficiently. Furthermore, since the formwork cannot be reused after being removed, it has to be discarded, resulting in a large amount of wood resources being wasted.

Regarding the technique of forming a shipping opening using a formwork other than wood, for example, Patent Document 1 describes a technique called "Formwork for forming a floor penetration opening", which involves pouring concrete into the floor of a building under construction. In particular, an invention relating to a formwork used to form a floor through-hole (shipping opening) for communication with the floor below is disclosed.
The formwork disclosed in Patent Document 1 consists of a perforated iron plate in which small holes are formed over the entire area, and a reinforcing steel frame body to which the perforated iron plate is attached to the side surface. It is characterized by comprising a peripheral wall skeleton having a shape and size corresponding to the peripheral wall of the communication floor through-hole.
In this way, if the formwork is made of reinforcing steel, there is no problem even if the formwork is buried in the concrete slab without being removed after the concrete has solidified, so there is no need to remove the formwork. When using this formwork, unlike when using a wooden formwork, a large amount of wood resources will not be wasted. Furthermore, since the pre-formed small holes can be used when inserting slab reinforcement into the formwork, reinforcement work for the installed formwork can be performed efficiently.

Furthermore, although it does not relate to the technology for forming openings in slabs for use in lifting and lowering construction materials and tools, Patent Document 2 describes a high-rise Disclosed is an invention relating to a frame (formwork) used to form a temporary support insertion opening provided at the intersection of a floor slab and temporary support of a work stage temporarily installed in a construction space during construction work of a building, etc. ing.
The frame for the temporary support insertion hole disclosed in Patent Document 2 is made of reinforced concrete containing alkali-resistant glass fiber, has an inverted table shape whose width is gradually widened toward the upper opening end of the rectangle, and has a peripheral edge portion on the lower side wall. The structure is characterized in that a column insertion hole is provided except for the column, and a through hole for reinforcing reinforcement is formed in each side wall surface.
In this way, if the frame is made of reinforced concrete containing alkali-resistant glass fiber, even if the frame is buried in the concrete slab without being removed when concrete is poured into the temporary support insertion hole, the floor slab will not be damaged. No reduction in strength. That is, since the frame of the above structure does not need to be removed, the effort and cost required for removal work can be reduced. In addition, through-holes for reinforcement are formed in each side wall of the frame, and when assembling the frame, the ends of the floor slab reinforcing bars at the column insertion openings can be passed through the through-holes and protruded into the frame. Since the reinforcing bars can be used when pouring concrete into the temporary support insertion opening after the temporary support support has been removed, the work of backfilling the temporary support insertion opening can be performed efficiently.

Further, in Patent Document 3, entitled "Formwork for slab opening and method for forming slab opening using the same", there is a method for forming an opening in a concrete slab using a flexible synthetic resin sheet. An invention related to a technique for using poured concrete as a dam member is disclosed.
The invention related to the formwork for slab opening disclosed in Patent Document 3 is one that is installed on a flat plate material constituting a part of the formwork for slab formation, and the first formwork is rectangular in plan view. A frame, four holding means for holding the four corners of the first frame, four supports for supporting the four holding means from below, and a flexible rectangular shape made of synthetic resin. and fixing means for fixing the four sides of the sheet to the first frame, and the sheet is spread over the flat material and attached to the first frame through the holding means. With the lower ends of the four supports installed at each of the four corners of the seat fixed at four locations at equal distances from the center in plan view, lift the four sides of the seat and open the first frame. It is characterized by having a size that allows it to be folded inward from the outside so as to straddle the upper part.
In a formwork for opening a slab with this structure, if concrete is poured around the bottom and four sides covered with a sheet, the sheet will prevent the concrete from entering, so the sheet should cover the surroundings. No concrete slab is formed within the enclosed space. A synthetic resin sheet that is not buried in the concrete slab but is simply in contact with the surface of the concrete slab has a weak adhesion to the concrete, so it can be easily peeled off from the concrete slab. Furthermore, since the sheet can be easily cut using a cutter, etc., even if multiple slab lines pass through the sheet, the insertion holes of the slab lines formed in the sheet can be cut with a cutter, etc. By cutting it open, the sheet can be easily separated from the slab striations.

JP2003-239538A Japanese Unexamined Patent Publication No. 61-98844 Patent No. 6491386

In the invention disclosed in Patent Document 1, the structure uses small holes pre-formed in the formwork when passing slab lines through the formwork, so a heat insulating material or the like is placed at the bottom of the formwork for slab formation. When the height at which the slab reinforcements are placed changes due to the installation, there is a problem in that it is not possible to make fine adjustments to the locations where the slab reinforcements are passed through the formwork. Furthermore, since the formwork is made of reinforcing steel, there is a problem in that the manufacturing cost is high. Furthermore, it is difficult to remove the formwork after the concrete hardens, and the formwork must remain in the concrete slab. Therefore, the invention disclosed in Patent Document 1 requires a large amount of wood. Although it is possible to avoid the situation where resources are wasted, there is a problem in that a large amount of metal resources are wasted.

The invention disclosed in Patent Document 2 has a structure in which slab reinforcements can be protruded into the frame using through holes for reinforcement when the frame is assembled. There was a problem in that it was not possible to respond when the position where the threads were passed changed. Furthermore, since the frame is made of reinforced concrete containing glass fiber, there is a problem in that the manufacturing cost of the frame is high.

In the invention disclosed in Patent Document 3, the synthetic resin sheet used in place of the wooden or iron formwork is easy to remove after the concrete has hardened, and is also easier to remove than the case where the above formwork is used. Although it has the advantage of low manufacturing costs, if vibrations are transmitted to the sheet due to a worker walking around the formwork with the slab reinforcement inserted into the sheet, it is necessary to form the sheet to insert the slab reinforcement. There was a possibility that the pores formed would become larger. Furthermore, it is thought that there is room to further reduce manufacturing costs by reducing the number of parts and the like.

The present invention was made in response to these problems, and provides a shipping opening that can be manufactured at low cost and that allows for easy adjustment of the position of insertion holes for slab reinforcement and removal after solidification of concrete. The purpose of the present invention is to provide a formwork and a method of forming a shipping opening using the same.

In order to achieve the above object, the first invention provides a formwork for a shipping opening that is installed on a flat plate material that constitutes a part of the slab forming formwork when forming a shipping opening in a concrete slab. It consists of a box-shaped synthetic resin formwork body with an open top, consisting of four side plates and a rectangular bottom plate, and four first molds arranged to form a rectangular shape in plan view. It is characterized by comprising a bar and four receivers fixedly installed at each of the four corners of the formwork body on the upper end side of the side plate and holding both ends of the first bar, respectively. .
In the first invention, since the form body, which is fixed so that the first bottom plate is in close contact with the upper surface of the flat plate material constituting a part of the slab forming form, is made of synthetic resin, tools such as a drill are not required. By using this, insertion holes for slab reinforcement can be easily formed in the form body. Therefore, in the first invention, the formwork body does not interfere with reinforcement work.

Further, in the first invention, when concrete is poured around the formwork body installed on the flat plate of the slab forming formwork as described above, the invasion of concrete is blocked by the side plates and the bottom plate. , no concrete slab is formed inside the formwork body. At this time, the first bar acts to suppress deformation of the formwork body due to being pushed by the poured concrete.
Note that when the concrete hardens, the formwork body is not buried in the concrete slab, but simply has one side in contact with the surface of the concrete slab. Since the formwork body is made of synthetic resin, its adhesion to concrete is weaker than conventional formwork made of wood or metal. Therefore, the first invention has the effect that the work of peeling off the form body from the concrete slab is easy. In addition, since synthetic resin can be easily destroyed with tools such as crowbars, the first invention allows the formwork body to be removed from the slab reinforcements even when multiple slab reinforcements penetrate through the side plate. Easy to remove from concrete slab.

In addition, the second invention is based on the first invention, and further includes four pillar holding means attached to each of the four receivers, and four pillar holding means attached to the outside of the form body so as to be orthogonal to the first bottom plate. and four columns arranged and fixed one by one to each of the four receivers by the column holding means, and the column has a top end fixed to the flat plate material with the formwork main body installed on the flat plate material. It is characterized by having a length that allows contact with.
In the second invention, in addition to the effect of the first invention, the formwork body is separated from the first bar and the receiver by having the support bear a part of the load of the first bar and the receiver. It has the effect of reducing the load received.

A third aspect of the present invention is that in the second aspect, the column is provided with a male thread on its outer peripheral surface, and the column holding means is paired with a column fixing device that forms a U-shape in side view and has a receiver disposed therein. and a nut, the strut fixing device is configured to allow communication between an upper plate having a first through hole into which the strut is inserted, and a strut parallel to the upper plate and inserted into the first through hole. It includes a lower plate provided with a second through hole, and a connecting plate that connects the proximal ends of the upper plate and the lower plate, and the pair of nuts are screwed into the male threads of the column, and are attached to the column fixing device. It is characterized by being installed above and below the upper and lower plates with the upper and lower plates sandwiched between them.
In the third invention, in addition to the effect of the second invention, the upper plate and the lower plate are sandwiched from above and below with the support column communicating with the first through hole of the upper plate and the second through hole of the lower plate. The column is fixed to the column fixing device by tightening a pair of nuts as shown in FIG. It has the effect of being fixed to the tool.

A fourth invention is that in the third invention, the upper plate and the lower plate of the post fixing device are provided with a first through hole and a second through hole in which the post can be placed. A notch and a second notch are respectively formed from the proximal side to the distal side, and the first notch and the second notch are connected to the connection plate, so that the support can be placed inside. It is characterized in that the third notch is formed in a direction perpendicular to the upper plate and the lower plate.
In the fourth invention, in addition to the effect of the third invention, each nut is arranged such that the upper plate and the lower plate of the post fixing device are disposed between a pair of nuts screwed into the male threaded part of the post. After adjusting the position of the column, move the column placed inside the third notch from the proximal end to the distal end of the upper and lower plates while keeping it parallel to the connecting plate. It has the effect of passing through the cutout No. 3 and being placed inside the first cutout and the second cutout.

A fifth invention is the invention according to any one of the first to fourth inventions, in which the receiver includes a second bottom plate having an L-shape in a plan view, and a second base plate having an L-shape in a side view. It consists of an outer plate and an inner plate extending perpendicularly in the same direction from the outer edge and inner edge of the bottom plate, respectively, and the end of the first bar is It is characterized by having a concave groove arranged in it.
In the fifth invention, when the end of the first bar is placed in the groove of the receiver, the bottom of the first bar is held by the second bottom plate of the receiver, and the side part of the first bar is held by the second bottom plate of the receiver. Since it is held by the outer and inner plates of the tool, there is no risk of it accidentally shifting laterally and coming off the receiver. Therefore, in the fifth invention, in addition to the effects of any one of the first to fourth inventions, workability is good when installing the end of the first bar in the receiving tool. It has an effect.

A sixth invention is the invention according to any one of the first to fourth inventions, wherein the formwork body has a rectangular shape in plan view and extends outward from the upper ends of the four side plates in parallel with the first bottom plate. It is characterized in that it includes a frame plate extending to the frame plate, and the receiver is fixed to the frame plate.
In the sixth invention, in addition to the effects of any one of the first to fourth inventions, by arranging the receiver on the frame plate of the formwork main body, the upper end of the side plate of the formwork main body can be fixed. It has the effect of making it easier to accurately install the four receivers at each of the four corners of the side.

A seventh invention is based on the sixth invention, wherein the formwork body is provided with four outer plates that have a rectangular shape in plan view and extend vertically upward from the outer edge of the frame body plate. Features.
In the seventh invention, when the receiver is placed on the frame plate of the form body, the outer parts of the receiver are held by the outer plates of the form body, so that the receiver is inadvertently displaced laterally. There is no risk of it coming off the frame plate of the formwork body. Therefore, in addition to the effect of the sixth invention, the seventh invention has the effect of improving workability when arranging the four receivers at each of the four corners of the upper end side of the side plate of the form body.

An eighth invention is the invention according to any one of the first to fourth inventions, wherein the side plate of the form body has a trapezoidal shape in which the upper end side is shorter than the lower end side when viewed from above. It is characterized by the presence of
When the side plates of the formwork body are installed parallel to the vertical direction, the force applied upward in the vertical direction to the first bottom plate of the formwork body does not act in the direction of peeling the side plates from the concrete slab. It is necessary to apply a horizontal force to the side plate in addition to the above-mentioned force on the first bottom plate in order to separate it from the concrete slab. On the other hand, in the eighth invention, since the side plates of the form body are shaped to gradually expand upward, the force applied vertically upward to the first bottom plate of the form body is It also acts in the direction of peeling the side panels away from the concrete slab. Therefore, in the eighth invention, in addition to the effects of any one of the first to fourth inventions, the side plates of the formwork body are installed parallel to the vertical direction. It has the effect of being easy to peel off from the concrete slab.

A ninth invention is the invention according to any one of the first to fourth inventions, characterized in that at least a portion of the form body is provided with an uneven portion having a wave-shaped cross section. do.
In addition to having the effect of any one of the first to fourth inventions, the ninth invention has the effect of increasing the bending rigidity on the surface of the form body where the uneven portion is provided.

A tenth invention is characterized in that, in any one of the first to fourth inventions, the mold body is formed of a transparent member.
In the tenth invention, in addition to the effects of any one of the first to fourth inventions, since the form body is transparent, the operation of forming the insertion holes for the slab reinforcement is easy. has.

The 11th invention is the invention of any one of the 1st invention to the 4th invention, which is spanned orthogonally to two first bars arranged parallel to each other. It is characterized by comprising a second bar.
In the eleventh invention, in addition to the effects of any one of the first to fourth inventions, a pair of side plates on which two first bars are arranged at the upper end are arranged so that the first bars are connected to each other. Since they are respectively fixed to the second rods through the side plates, deformation such as a change in the distance between the pair of side plates is unlikely to occur in the formwork body.

A twelfth invention is the invention according to any one of the first to fourth inventions, in which the form body is composed of a pair of divided bodies, and the divided bodies include a first bottom plate and a pair of side plates parallel to each other. The formwork body is characterized in that it has a shape cut at the central portion of the first bottom plate by a plane perpendicular to the first bottom plate.
In the twelfth invention, in addition to the effects of any one of the first to fourth inventions, even if there are many formwork bodies used at the site, they can be grouped into divided bodies so that they are not bulky. Therefore, the formwork body can be easily transported and storage space can be saved. In addition, when the formwork body is peeled off from the concrete slab after the poured concrete has hardened, the formwork body is in a state of being divided into two from the beginning, so in the twelfth invention, the concrete The effect of the first invention, which is that the work of peeling off the formwork body from the slab is easy, is further exhibited. Furthermore, when manufacturing the formwork body by injection molding, it is only necessary to make a mold for each divided body, which has the advantage that the size of the mold is smaller than when the formwork body is not divided. .

A thirteenth invention is a method of forming a shipping opening in a concrete slab using the shipping opening form according to the first invention, wherein a process of fixing the form body to the frame body, a process of fixing four receivers one by one at each of the four corners of the form body on the upper end side of the side plate, and a process of fixing the four first bars so that their both ends are It is characterized by comprising the step of fixing it to the form body so as to be held by the respective receivers.
In this method of forming the shipping opening, since the formwork body is made of synthetic resin and the structure allows insertion holes for the slab reinforcement to be easily formed using a tool such as a drill, the loading opening is When arranging slab reinforcement inside the formwork, the formwork body does not interfere with the work. In addition, when concrete is poured around the unloading opening formwork to form a concrete slab within the formwork for forming a slab, the movement of the concrete is prevented by the formwork body. No concrete slab is formed. Furthermore, when a concrete slab is formed, the formwork body is not buried in the concrete slab, but simply has one side in contact with the surface of the concrete slab, so it is difficult to peel the formwork body from the concrete slab. is easy.

A fourteenth invention relating to a method for forming an unloading opening is the thirteenth invention, including the step of attaching four pillar holders one by one to the four receivers fixed to the formwork body; A process of arranging four pillars on the outside of the formwork body so that they are perpendicular to the flat plate material and whose tips are in contact with the flat plate material; The method is characterized by comprising a step of fixing each piece.
In addition to the effect of the thirteenth invention, in this method of forming a shipping opening, the first bar and the receiver are partially borne by the support, so that the first bar and the receiver are This has the effect of reducing the load applied to the formwork body.

According to the first invention, slab reinforcements can be easily placed even at locations that function as shipping openings after the concrete slab is formed. Furthermore, even if the formwork for the shipping opening according to the first invention is installed in the formwork for forming a slab in order to form a concrete slab, and concrete is placed around it, contact with the concrete may occur. It is only the formwork itself. Therefore, according to the first invention, there is an advantage that the concrete slab can be easily removed from the formwork for forming the slab after it is formed, and that the parts other than the formwork body can be reused any number of times. Furthermore, the work of peeling off the formwork body from the concrete slab and the work of separating it from the slab reinforcement can be easily performed.
Although it is difficult to reuse the form body taken out from the concrete slab, the material cost of the form body in the first invention is much lower than that of a metal form body. Therefore, according to the first invention, it is possible to form a shipping opening in a part of a concrete slab at low cost. Furthermore, in the first invention, when concrete is placed around the formwork body, deformation of the formwork body is suppressed by the first bar material, so it is possible to use a formwork body with a thin wall thickness. It is possible. When such a formwork body is used, the work of peeling off the formwork body from the concrete slab can be performed even more easily.

According to the second invention, since the load that the formwork body receives from the first bar and the receiver is reduced by the supports, it is possible to use a formwork body whose wall thickness is even thinner than in the case of the first invention. I can do it. This makes it easier to peel off the formwork body from the concrete slab.

As the strut holding means in the first invention, for example, a plate material having a screw hole into which the strut is screwed, the outer circumferential surface of which is provided with a male screw, is fixed to the receiver with a screw or the like. When removing the formwork body from the concrete slab, it is necessary to remove the receiver from the formwork body and also to remove the column holding means and column from the receiver, but in the column holding means of the above structure, the plate material is removed from the column. It's not easy. On the other hand, in the third aspect of the invention, the strut fixture can be easily removed from the strut by loosening the tightening of the pair of nuts to the strut fixture. Therefore, according to the third invention, in addition to the effects of the second invention, it is possible to efficiently remove the post holding means from the post after forming the concrete slab in a short time.

In the third invention, when removing the post holding means from the post after forming a concrete slab, the nut located above of the pair of nuts is loosened and pulled out above the post, and then the post fixing device is removed from above the post. must be extracted to. On the other hand, in the fourth invention, by loosening the tightening of the pair of nuts on the column fixing device and then moving the column fixing device horizontally, it is possible to easily remove the column fixing device from the column. . Therefore, according to the fourth aspect of the invention, the effect of the third aspect of the invention in that the work of removing the column holding means from the column after forming the concrete slab can be performed efficiently in a short time is further exhibited.

As the receiver in any one of the first to fourth inventions, for example, a structure consisting only of a plate material having an L-shape in plan view can be considered. However, in a receiver having such a structure, there is a possibility that the first bar shifts in the horizontal direction and comes off from the receiver during the work of fixing the first bar to the receiver. On the other hand, in the fifth invention, since the outer plate and inner plate of the receiver prevent the first bar from shifting in the horizontal direction, the first bar may be accidentally removed from the receiver. There is no risk of it coming off. Therefore, according to the fifth invention, in addition to the effects of any one of the first to fourth inventions, the work of installing the end of the first bar in the receiving tool can be done quickly and efficiently. It has the effect of being able to perform well.

When fixing the receiver to the form body according to any one of the first to fourth inventions, for example, the receiver is fixed to the upper part of the side plate of the form body using screws or the like. There is a need. However, in such a structure, the position where the receiver is screwed to the formwork body may not be constant. On the other hand, in the sixth aspect of the invention, since the receiver can be placed on the frame plate when installed in the formwork body, it is possible to always fix the receiver at a fixed location with respect to the formwork body. can. Therefore, according to the sixth invention, in addition to the effects of any one of the first to fourth inventions, the work of fixing the receiver to the form body can be performed efficiently in a short time. This effect is achieved.

In the sixth invention, there is a possibility that the receiver shifts horizontally and comes off from the form body during the work of fixing the receiver to the form body. On the other hand, according to the seventh aspect of the invention, since the outer plate prevents the receiver from shifting in the horizontal direction, there is no fear that the receiver will inadvertently come off from the form body. Therefore, according to the seventh invention, the effect of the sixth invention that the work of fixing the receiver to the formwork body can be performed efficiently in a short time is further exhibited.

According to the eighth invention, since the form body can be easily peeled off from the concrete slab, in addition to the effects of any one of the first to fourth inventions, the form body is removed after the concrete slab is formed. This has the effect that the work can be done efficiently in a short time. In addition, in order to form the shipping opening, it is necessary for a worker to reach out from above the formwork body and cut and bend the slab strips placed inside the formwork body. In the eighth invention, since the form body is shaped so that the upper part is wider than the lower part, this work can be performed extremely easily.

In the ninth invention, since the surface of the formwork body on which the uneven portion is provided has high bending rigidity, a formwork body having a thinner wall thickness than those in the first to fourth inventions is used. I can do it. Therefore, according to the ninth invention, in addition to achieving the effects of any one of the first to fourth inventions, the work of peeling off the formwork body from the concrete slab becomes easier. It will be demonstrated even more.

In the tenth invention, since the form body is transparent and it is easy to form the insertion holes for the slab reinforcement, in addition to the effects of any one of the first to fourth inventions, the concrete slab can be formed. This has the effect that the work of arranging slab stripes at a location that will function as an unloading opening after opening can be performed efficiently in a short time.

In the eleventh invention, since deformation such as a change in the distance between the pair of side plates with the two first bars disposed at the upper end is unlikely to occur in the formwork body, a formwork body with a thin wall thickness is used. This makes it easier to peel off the formwork body from the concrete slab. That is, according to the eleventh invention, in addition to achieving the effects of any one of the first to fourth inventions, the formwork body can be efficiently peeled off from the concrete slab in a short time. be effective.

According to the twelfth invention, by making the formwork body less bulky, transportation of the formwork body becomes easier and storage space is saved. In addition to this effect, it also has the effect of reducing costs required for transportation and storage. Moreover, since the work of peeling off the formwork body from the concrete slab is easy, according to the twelfth invention, it is possible to efficiently perform the work of removing the concrete slab after it is formed in a short time. Furthermore, in the twelfth invention, when manufacturing the mold main body by injection molding, a small mold can be used, so that the mold body can be manufactured at low cost.

According to the thirteenth invention, slab lines can be easily arranged inside the formwork for unloading opening. In addition, when concrete is poured around the formwork for a shipping opening installed inside the formwork for forming a slab, it is easy to remove the formwork for the shipping opening from within the formwork for forming a slab after forming the concrete slab. can be taken out. Furthermore, the formwork for the shipping opening removed from the concrete slab can be reused any number of times, excluding the formwork body. That is, according to the thirteenth invention, all the members of the formwork for the shipping opening used when forming the concrete slab, except for the formwork body, can be reused. can be formed at low cost.
Further, according to the thirteenth invention, since the slab reinforcement is also arranged inside the formwork for the loading opening, in order to close the used loading opening, the concrete slab formed inside the loading opening is sufficiently It can provide great strength.

According to the fourteenth invention, since the load that the form body receives from the first bar and the receiver is reduced by the supports, a form body whose wall thickness is even thinner than in the case of the thirteenth invention is used. This has the effect that the work of peeling off the formwork body from the concrete slab can be performed more easily.

(a) is a perspective view showing an example of the external appearance of a formwork for an unloading opening according to an embodiment of the present invention, and (b) is a perspective view of the formwork main body shown in Fig. 3(a). . (a) and (b) are a perspective view and a plan view, respectively, of the receiver shown in FIG. 1(e) and (f) are perspective views of the support and crosspiece shown in FIG. 1(a), respectively. FIG. 1(a) is a plan view of a divided body of the formwork body shown in FIG. 1(b), and FIG. 1(b) is a view taken in the direction of arrow A in FIG. 1(a). 2 is a flowchart showing a procedure for forming a shipping opening in a concrete slab using the shipping opening form shown in FIG. 1(a). (a) is a plan view of the formwork body installed on the plywood of the formwork for forming a slab, and (b) is a sectional view taken along the line BB in the same figure (a). (a) is a perspective view showing how the receivers and crosspieces are installed on the formwork body in Fig. 5(a), and (b) is a perspective view showing how reinforcing crosspieces are installed on the formwork body in Fig. It is a perspective view showing how it is installed. (a) is a perspective view showing a state in which the support fixture is installed on the formwork main body in FIG. FIG. (a) and (b) are a perspective view and a plan view, respectively, showing a state in which slab reinforcements are inserted into slab reinforcement insertion holes provided in the formwork body in FIG. 7(b). (a) is a sectional view taken along the line CC in FIG. 8(b), and (b) is a diagram showing a state in which concrete has been placed around the formwork body in FIG. 8(a). , (c) is a diagram showing a state in which the slab lines in the formwork main body are cut and the ends are bent in the same figure (b). (a) and (b) are a cross-sectional view and a perspective view, respectively, showing the state in which the formwork for the shipping opening in Fig. 9(c) has been removed, and (c) is the bent slab in Fig. 9(a). It is a diagram showing a state in which the muscle is returned to its original straight state and the cut portion is joined. (a) is an external perspective view of the pipe fixing member, and (b) is a diagram showing a state in which the pipe fixing member is installed around the shipping opening in FIG. 10(b).

The structure of the formwork for a shipping opening of the present invention and the method of forming a shipping opening in a concrete slab using the formwork for a shipping opening will be specifically explained using FIGS. 1 to 11.
The formwork for the shipping opening of the present invention is made of wood such as plywood, which is used as a part of the formwork when forming a shipping opening in a concrete slab in a building whose structural material is reinforced concrete or steel-framed reinforced concrete. It is installed on the top surface of a flat metal plate such as a flat plate or deck plate.
Therefore, in this specification, expressions such as "upper plate", "lower plate", or "upper and lower" are used assuming that the formwork for shipping opening is used in such a state. Furthermore, as a specific example of a method for forming a shipping opening in a concrete slab using the shipping opening formwork of the present invention, a case will be described in which the flat plate material that constitutes a part of the slab forming formwork is plywood. However, even when the flat plate material is a metal deck plate, the functions and effects of the present invention related to the method for forming a shipping opening described below are similarly exhibited.

FIG. 1(a) is a perspective view showing an example of the external appearance of the formwork for unloading opening according to the embodiment of the present invention, and FIG. 1(b) is a perspective view of the formwork main body shown in FIG. 1(a). FIG. 2(a) and 2(b) are a perspective view and a plan view, respectively, of the receiver shown in FIG. 1(a), and FIG. 2(c) and FIG. FIG. 4 is a perspective view and a plan view of the column fixing device shown in a). 2(e) and 2(f) are perspective views of the support and crosspiece shown in FIG. 1(a), respectively. Note that FIG. 2(e) shows a state in which a pair of nuts are attached to the support column.

As shown in FIG. 1(a), the unloading opening form 1 of the present invention consists of a pair of divided bodies 7, 7 of the same shape, including a box-shaped form body 2 with an open top, and Four receivers 3 are installed at each of the four corners of the upper end (opening end) of the frame body 2, and a post fixture 4 has a U-shape in side view and the receivers 3 are arranged inside. Two pairs of crosspieces 5a, 5a and 5b, 5b arranged to form a rectangular shape in plan view and held at both ends by the receivers 3, and a pair of crosspieces 5a, 5a arranged parallel to each other. On the other hand, it is provided with a pair of parallel crosspieces 5c, 5c spanned orthogonally, and four columns 6, one each attached to each of the four column fixing devices 4.
Although the formwork 1 for a shipping opening shown in FIG. 1(a) uses crosspieces 5a to 5c made of wooden square timbers, the formwork for a shipping opening of the present invention is not limited to such a structure. For example, instead of a wooden block, a metal bar having a cross-sectional shape other than a rectangle may be used. Moreover, although the frame body 2 is formed of transparent polycarbonate, the frame body 2 may be formed of a transparent synthetic resin other than polycarbonate.

The formwork main body 2 includes a rectangular first bottom plate 2a, and two pairs of side plates 2b, 2b, which form a trapezoid whose upper side (upper end side) is shorter than the lower side (lower end side) when viewed from above. 2c, 2c, and a frame plate 2d having a rectangular shape in plan view and extending outward from the upper ends of the two pairs of side plates 2b, 2b and 2c, 2c in parallel with the first bottom plate 2a, and a rectangular shape in plan view. It is constituted by two pairs of outer plates 2e, 2e and 2f, 2f extending vertically upward from the outer edge of the frame plate 2d.
As shown in FIG. 1(b), the pair of divided bodies 7, 7 are arranged so that the formwork main body 2 shown in FIG. 2b, and has a shape cut by a plane perpendicular to 2b.
In addition, in Fig. 1(a), the end surfaces 7a, 7a (see Fig. 1(b)) of the pair of dividing bodies 7, 7 are in contact with each other, but the loading opening is actually formed in the concrete slab. In order to prevent the poured concrete from entering the pair of divided bodies 7, 7 from between the end faces 7a, 7a, as will be described later, one divided body 7 is placed on top of the other divided body 7. It is desirable to install the formwork main body 2 on the plywood 12 (see FIG. 5(a) or FIG. 5(b)) of the slab forming formwork in such a manner that the divided bodies 7 partially overlap.

In this way, in the formwork 1 for unloading opening, the formwork main body 2 is composed of a pair of divided bodies 7, 7, so if there are many formwork bodies 2 used at the site, each divided body 7 By grouping them together, you can make it less bulky. In this way, the form body 2 can be easily transported and the storage space can be saved, so that the cost required for transport and storage can be reduced. Furthermore, when the mold body 2 is manufactured by injection molding, it is sufficient to make a mold for each divided body, so the size of the mold becomes smaller than when the mold body is not divided. That is, in the unloading opening mold 1 having the above structure, a small mold can be used when manufacturing the mold main body 2 by injection molding, so that it can be manufactured at low cost.

As shown in FIGS. 2(a) and 2(b), the receiver 3 includes a second bottom plate 3a provided with screw fixing holes 8a and having an L-shape in plan view, and an L-shape in side view; It consists of an outer plate 3b and an inner plate 3c extending vertically in the same direction from the outer edge and inner edge of the second bottom plate 3a, respectively. That is, in the receiver 3, the second bottom plate 3a, the outer plate 3b, and the inner plate 3c form a groove in which the ends of the crosspieces 5a, 5b are arranged.
Further, as shown in FIGS. 2(c) and 2(d), the column fixing device 4 is made of a rectangular plate bent twice at right angles so as to form a U-shape when viewed from the side, and has screw fixing holes 8b, 8b are provided at desired intervals in the longitudinal direction, a lower plate 4b parallel to the upper plate 4a, and a connecting plate 4c connecting the proximal ends of the upper plate 4a and the lower plate 4b. has been done. Note that a first notch 9a and a second notch 9b each having a predetermined length from the proximal end in parallel with the longitudinal direction are formed in the upper plate 4a and the lower plate 4b, and the connecting plate 4c A third notch 9c connecting the first notch 9a and the second notch 9b is formed in a direction perpendicular to the upper plate 4a and the lower plate 4b.

As shown in FIG. 2(e), the pillar 6 has a thickness that allows it to be placed inside the first notch 9a, second notch 9b, and third notch 9c of the pillar fixture 4, It is made of a rod-shaped body with one end sharpened, and a male screw portion 6b is formed on the outer circumferential surface 6a over a predetermined length from the other end. The structure is such that it is fixed to the pillar fixture 4 by using a pair of nuts 10, 10 that are screwed into the male threaded portion 6b, as will be described later. That is, the strut fixture 4 and the pair of nuts 10, 10 constitute strut holding means for fixing the strut 6 to the receiver 3.
As shown in FIG. 2(f), the crosspieces 5a to 5c are elongated wooden blocks, and the width w of the crosspieces 5a and 5b (see FIG. 2(f)) is the width W of the second bottom plate 3a of the receiver 3. ₁ (see FIG. 2(b)), and the thickness t of the crosspieces 5a, 5b (see FIG. 2(f)) and the thickness T of the second bottom plate 3a of the receiver 3 (see FIG. 2(a) ) and the width W ₂ (see FIG. 2(a)) of the outer plate 3b and inner plate 3c (see FIG. c)). The length of the crosspiece 5a is determined by the outer plate 3b of the pair of holders 3, which respectively hold both ends of the crosspiece 5a while being fixed to the upper end of the form body 2 installed in the slab forming formwork. , 3b, and longer than the distance between the second bottom plates 3a, 3a in the pair of receivers 3, 3 described above.

In addition, the length of the crosspiece 5b is determined by the outer plate 3b in a pair of holders 3, 3 that respectively hold both ends of the crosspiece 5b while being fixed to the upper end of the form body 2 installed in the slab forming formwork. , 3b, and longer than the distance between the second bottom plates 3a, 3a in the pair of receivers 3, 3 described above. That is, the crosspieces 5a and 5b have a structure in which both ends can be placed inside the receiver 3, and can be placed inside the column fixture 4 with both ends placed inside the receiver 3. There is.
In addition, the length of the crosspiece 5c is set to the length of the formwork main body 2 installed in the slab forming formwork so that the crosspiece 5c can be spanned perpendicularly to the pair of crosspieces 5a, 5a arranged in parallel. It is longer than the distance between the pair of outer plates 2f, 2f.

FIG. 3(a) is a plan view of the divided body of the formwork body shown in FIG. 1(b), and FIG. 3(b) is a view taken in the direction of arrow A in FIG. 3(a). As shown in FIGS. 3(a) and 3(b), uneven portions 11 are provided on the first bottom plate 2a and side plate 2c of the form body 2. As shown in FIGS. Note that the uneven portion 11 of the first bottom plate 2a has a wavy cross-sectional shape when cut along a plane perpendicular to both the first bottom plate 2a and the outer plate 2e in a portion where the uneven portion 11 is not provided. The uneven portion 11 of the side plate 2c has a wavy cross-sectional shape when cut along a plane perpendicular to both the side plate 2c and the outer plate 2e where the uneven portion 11 is not provided.
In this case, the uneven portion 11 increases the rigidity of the first bottom plate 2a against bending such that the side connected to the side plate 2c and the end surface 7a (see FIG. 1(b)) becomes convex upward or downward. At the same time, the rigidity of the side plate 2c against bending such that the side connected to the frame plate 2d and the side connected to the first bottom plate 2a becomes convex inwardly or outwardly is increased. That is, the unloading opening form 1 has the effect of increasing the bending rigidity on the surface of the form body 2 on which the uneven portions 11 are provided. Therefore, in the unloading opening mold 1, a thin mold body 2 can be used.
Note that the uneven portion 11 may be provided not only on the first bottom plate 2a and the side plate 2c but also on the side plate 2b, or may be provided only on the first bottom plate 2a. Furthermore, the form body 2 may have a structure in which the uneven portions 11 are not provided.

Next, a method for forming a shipping opening in a concrete slab using the shipping opening form 1 will be specifically described with reference to FIGS. 4 to 11. Note that FIG. 4 is a flowchart showing a procedure for forming a shipping opening in a concrete slab using the shipping opening form 1. Further, FIG. 5(a) is a plan view of the formwork main body showing the state in which the formwork for slab formation is installed on the plywood, and FIG. 5(b) is a plan view of the formwork as viewed from the line BB in FIG. FIG. Furthermore, FIG. 6(a) is a perspective view showing how the receivers and crosspieces are installed on the formwork main body in FIG. 5(a), and FIG. 6(b) is a perspective view showing how the formwork main body is installed in FIG. FIG. 3 is a perspective view showing how reinforcing crosspieces are installed. FIG. 7(a) is a perspective view showing a state in which the post fixing tool is installed on the formwork body in FIG. 6(b), and FIG. FIG. 3 is a perspective view showing a state in which the support pillars are installed.
8(a) and 8(b) are a perspective view and a plan view, respectively, showing a state in which the slab reinforcement is inserted into the slab reinforcement insertion hole provided in the form body in FIG. 7(b). Moreover, FIG. 9(a) is a cross-sectional view taken along the line CC in FIG. 8(b), and FIG. 9(b) is a state in which concrete has been placed around the formwork body in FIG. 9(a). FIG. 9(c) shows a state in which the slab lines in the form body in FIG. 9(b) are cut and the ends are bent. Furthermore, FIGS. 10(a) and 10(b) are a cross-sectional view and a perspective view, respectively, showing a state in which the shipping opening formwork in FIG. 9(c) has been removed, and FIG. 10(c) is a The slab strips bent in (a) are returned to their original straight state, and the cut portions are joined. 11(a) is an external perspective view of the pipe fixing member, and FIG. 11(b) shows a state in which the pipe fixing member is installed around the shipping opening in FIG. 10(b).
In order to avoid complicating the diagrams, only some of the screws in FIGS. 9(c), FIG. 10(c), and FIG. 11(b), only some of the slab lines are labeled. Furthermore, illustration of the uneven portions is omitted in FIGS. 5(a), 5(b), 8(b), and FIGS. 9(a) to 9(c). Further, the constituent elements shown in FIGS. 1 to 3 are given the same reference numerals, and the description thereof will be omitted as appropriate.

As shown in step S1 in FIG. 4, first, the plywood 12 constituting the formwork for slab formation is marked out to identify the location where the shipping opening is planned to be formed, and then one of the divided bodies 7 The formwork main body 2 is installed at the corresponding location on the plywood 12 in such a manner that a part of the other divided body 7 overlaps with the plywood 12. Then, using screw fixing holes (not shown) provided in the first bottom plate 2a, the first bottom plate 2a is fixed to the plywood 12 with screws 13 (see FIGS. 5(a) and 5(b)). reference). In addition, in the unloading opening form 1, the form body 2 is formed of a transparent member, and the condition of the plywood 12 can be visually confirmed through the form body 2 during the above work, so the worker can The form body 2 can be efficiently installed in the correct position relative to the frame body 12.

Next, in step S2, after installing the receivers 3 one by one at each of the four corners of the upper end of the formwork body 2, the screws 13 are attached to the formwork body using the screw fixing holes 8a (see FIG. 2(b)). The receiver 3 is fixed to the frame plate 2d of No.2. Note that if the frame body 2 is not provided with the frame plate 2d, it is difficult to screw the receiver 3 at a fixed position with respect to the form body 2. On the other hand, in the formwork 1 for unloading opening having the above structure, the frame plate 2d can be used when installing the receiver 3 on the formwork main body 2. Therefore, according to the formwork 1 for unloading opening, the receiver 3 can always be fixed at a fixed position with respect to the formwork main body 2.
In addition, if the formwork body 2 is not provided with the outer plates 2e and 2f, when the receiver 3 is placed on the frame plate 2d of the formwork body 2, the receiver 3 may shift horizontally and the formwork There is a possibility that it will come off from the main body 2. On the other hand, in the unloading opening form 1 having the above structure, the outer side of the receiver 3 is held by the outer plates 2e and 2f of the form body 2, so the receiver 3 is inadvertently moved laterally. There is no risk of it shifting and coming off the frame body plate 2d of the form body 2. Therefore, according to the unloading opening form 1, the work of fixing the receiver 3 to the form body 2 can be performed efficiently in a short time.

Thereafter, as shown in FIG. 6(a), two pairs of crosspieces 5a, 5a and 5b, 5b arranged to form a rectangular shape in a plan view are placed in a formwork so that both ends thereof are held by the receivers 3. After installing it on the main body 2, use the screw fixing holes (not shown) provided in the outer plates 2e, 2f to attach two pairs to the outer plates 2e, 2f of the formwork main body 2 with screws (not shown). The crosspieces 5a, 5a and 5b, 5b are fixed respectively. Furthermore, a pair of crosspieces 5c, 5c are orthogonally bridged over a pair of crosspieces 5a, 5a arranged parallel to each other (see FIG. 6(b)). Thereafter, the pair of crosspieces 5c, 5c are fixed to the pair of crosspieces 5a, 5a using screws (not shown).

The two pairs of crosspieces 5a, 5a and 5b, 5b are designed to prevent the formwork body 2 from being pushed by the concrete and deforming when concrete is placed around the formwork body 2, as will be described later. Acts as a suppressor. In addition, in the formwork 1 for unloading opening, the pair of side plates 2b, 2b are respectively fixed to the pair of crosspieces 5c, 5c via the pair of crosspieces 5a, 5a, so the interval between the pair of side plates 2b, 2b is It is difficult for the form body 2 to undergo deformation that would cause a change in the shape. In this way, in the formwork 1 for unloading opening, when concrete is placed around the formwork body 2, the formwork body is Since the deformation of the mold body 2 is suppressed, it is possible to use the form body 2 with a thin wall thickness.

In addition, when the receiver 3 consists only of the second bottom plate 3a that is L-shaped in plan view, the crosspieces 5a and 5b may shift horizontally during the work of fixing the crosspieces 5a and 5b to the receiver 3. There is a possibility that it will deviate from 3. On the other hand, in the formwork 1 for unloading opening, the two pairs of crosspieces 5a, 5a and 5b, 5b are connected to the receiver 3 whose ends are formed by the second bottom plate 3a, the outer plate 3b, and the inner plate 3c. It is placed in a concave groove, and its bottom is held by the second bottom plate 3a of the receiver 3, and its sides are held by the outer plate 3b and inner plate 3c of the receiver 3, so that it may be accidentally placed sideways. There is no risk of it shifting in the direction and coming off the receiver 3. Therefore, according to the formwork 1 for unloading opening, the work of installing the ends of the crosspieces 5a, 5b inside the receiving tool 3 can be performed efficiently in a short time.

In step S3, the support 3 and crosspieces 5a and 5b placed on the form body 2 are sandwiched from above and below by the upper plate 4a and the lower plate 4b together with the frame body plate 2d, and the support fixture 4 is attached to the form body 2. (see Figure 7(a)). Then, using the two screw fixing holes 8b, 8b (see FIGS. 2(c) and 2(d)), the upper plate 4a of the column fixing tool 4 is fixed to the two pairs of crosspieces 5a with screws (not shown). , 5a and 5b, 5b, respectively.
In addition, in the shipping opening form 1, the upper plate 4a and the lower plate 4b of the column fixing device 4 are arranged between a pair of nuts 10, 10 screwed into the male threaded portion 6b of the column 6. After adjusting the position of each nut 10, while maintaining the column 6 placed inside the third notch 9c parallel to the connecting plate 4c, move it from the base end side to the tip end of the upper plate 4a and lower plate 4b. When moved to the side, the strut 6 passes through the third notch 9c and is placed inside the first notch 9a and the second notch 9b. In addition, when removing the column fixing device 4 from the column 6 after the concrete has hardened, after loosening the tightening of the column fixing device 4 by the pair of nuts 10, 10, move the column fixing device 4 horizontally in the direction away from the column 6. By doing so, the post fixture 4 can be easily removed from the post 6. Therefore, in the formwork 1 for unloading opening, the work of installing the pillar 6 on the pillar fixture 4 and the work of removing the pillar fixture 4 from the pillar 6 can be performed efficiently in a short time.

The column holding means for fixing the column 6 to the formwork body 2 may include, for example, a screw hole into which the column 6 is screwed, the column 6 having a male threaded portion 6b provided on the outer circumferential surface, and fixed to the receiver 3 with a screw or the like. A plate material with a structure that When removing the formwork main body 2 from the concrete slab, it is necessary to remove the support 3 from the formwork main body 2 and also to remove the column holding means and the support 6 from the support 3, but in the column holding means of the above structure, It is not easy to remove the plate material from the support column 6. On the other hand, in the strut fixture 4 shown in FIG. 2(c), the strut fixture 4 can be easily removed from the strut 6 by loosening the tightening of the pair of nuts 10, 10.
In addition, in the strut fixture 4, the first notch 9a, the second notch 9b, and the third notch 9c are provided in the upper plate 4a, instead of being provided in the upper plate 4a, the lower plate 4b, and the connecting plate 4c. The lower plate 4b may have a structure in which a first through hole is provided through which the support column 6 is inserted, and a second through hole is provided in the lower plate 4b so that the support support 6 inserted through the first through hole can communicate with each other. can. In the strut fixture 4 having such a structure, the upper plate 4a and the lower plate 4b are connected from above and below with the strut 6 communicating with the first through hole of the upper plate 4a and the second through hole of the lower plate 4b. The support column 6 is fixed by tightening the pair of nuts 10, 10 so as to sandwich them therebetween.
However, in this case, when removing the post fixture 4 from the post 6 after forming the concrete slab, loosen the upper nut 10 of the pair of nuts 10, 10 and pull it out above the post 6. Since it is necessary to pull out the column fixing device 4 above the column 6, the workability when removing the column fixing device 4 from the column 6 is poor compared to the column fixing device 4 shown in FIG. 2(c).

Next, in step S4, the heat insulating material 14 is spread over the part of the plywood 12 where the form body 2 is not installed. Further, in step S5, after arranging the four pillars 6 outside the formwork body 2 so that they are perpendicular to the plywood 12 and their tips are in contact with the plywood 12, the first of the four pillar fixtures 4 is One each is arranged inside the notch 9a and the second notch 9b. Then, by tightening the upper and lower nuts 10, 10 (see FIG. 2(e)), the upper plate 4a and the lower plate 4b are sandwiched from above and below, and the column 6 is fixed to the column fixture 4 (see FIG. 7). (see (b)).
At this time, the four supports 6 bear part of the load of the crosspieces 5a, 5b and the receiver 3, so the load that the formwork body 2 receives from the crosspieces 5a, 5b and the receiver 3 is reduced. . Therefore, in the unloading opening form 1, the wall thickness of the form main body 2 can be reduced.

In step S6, a plurality of reinforcing bars called slab reinforcements (hereinafter referred to as slab reinforcements 15) are arranged in a grid inside a slab forming formwork (not shown) of which the plywood 12 constitutes a part. For this purpose, slab reinforcement insertion holes are formed in the form body 2. In addition, in the formwork 1 for shipping opening, the formwork main body 2 is made of transparent synthetic resin, and slab reinforcement insertion holes (not shown) can be easily formed by using a tool such as a drill. Therefore, the formwork body 2 does not interfere with reinforcement work.
Then, in step S7, the slab reinforcements 15 are inserted into the slab reinforcement insertion holes formed in the form body 2, and a plurality of slab reinforcements 15 are horizontally arranged inside the unloading opening form 1 (Fig. 8 (a) and FIG. 8(b) and FIG. 9(a)).
As described above, according to the formwork 1 for the unloading opening, it is easy to form the slab reinforcement insertion holes, so the slab reinforcements 15 are arranged at the location that will function as the unloading opening after the concrete slab is formed. tasks can be done efficiently and in a short time.

In step S8, concrete is poured around the unloading opening form 1 within the slab forming form, so that the lower nut 10 attached to the support column 6 is buried as shown in FIG. 9(b). The concrete slab 16 is formed to a height that does not exceed the maximum height (see FIG. 9(b)). At this time, since the formwork body 2 prevents concrete from entering the inside of the formwork 1 for shipping opening, a concrete slab 16 is placed inside the formwork 1 for shipping opening surrounded by the formwork body 2. is never formed.
In addition, since the first bottom plate 2a of the form body 2 is fixed to the plywood 12 using screws 13 in a tight state so that there is no gap, the first bottom plate 2a of the form body 2 can be stamped around the form 1 for unloading opening. There is no possibility that the placed concrete will enter between the first bottom plate 2a of the form body 2 and the plywood 12.

In step S9, as shown in FIG. 9(c), all exposed slab stripes 15 inside the unloading opening form 1 are cut at their central portions, and then their ends are cut. Fold each part upwards. In addition, in the formwork 1 for unloading opening, the formwork main body 2 is shaped such that the upper part is wider than the lower part, so the worker can reach out from above the formwork main body 2 and open the formwork. The work of cutting and bending the slab striations 15 arranged inside the main body 2 can be performed extremely easily.
Thereafter, in step S10, the unloading opening form 1 is removed (see FIGS. 10(a) and 10(b)). Specifically, first, remove the screws (not shown) fixing the upper plate 4a of the column fixing device 4 to the crosspieces 5a, 5b, rotate the column fixing device 4, and remove the upper plate 4a and lower plate 4b. After the receiving tool 3 and the crosspieces 5a, 5b are not placed between them, the post fixing tool 4 is moved horizontally and placed inside the first notch 9a and the second notch 9b. Remove it from the pillar 6 where it was attached. Next, the screws (not shown) of the crosspieces 5a to 5c are removed to remove the crosspieces 5a to 5c from the form body 2, and then the screws 13 are removed to remove the receiver 3 from the form body 2. Then, the form body 2 is removed from the slab striations 15.

Note that the formwork body 2 to be removed from the concrete slab 16 in step S10 is not buried in the concrete slab 16, but is in a state where one side is simply in contact with the surface of the concrete slab 16, as shown in FIG. 9(b). It becomes. Furthermore, since the formwork body 2 is made of synthetic resin, it has weaker adhesion to concrete than conventional formwork made of wood or metal, and can be easily destroyed with a tool such as a crowbar. The form body 2 is composed of two divided bodies 7, 7, and since it is only necessary to remove each divided body 7 from the slab line 15, a plurality of slab lines are provided on the side plates 2b, 2c of the form body 2. Even when the formwork body 2 is penetrated through the slab reinforcement 15, it is easy to remove the formwork body 2 from the slab reinforcement 15.

When the side plates 2b and 2c of the formwork main body 2 are installed parallel to the vertical direction, the force applied vertically upward to the first bottom plate 2a in an attempt to pull up the formwork main body 2 is caused by the side plates 2b, 2c, 2c from the concrete slab 16. Therefore, in order to peel off the side plates 2b, 2c from the concrete slab 16, it is necessary to apply a horizontal force to the side plates 2b, 2c in addition to the force applied vertically upward to the first bottom plate 2a.
On the other hand, when the side plates 2b and 2c of the formwork main body 2 have a shape that gradually widens upward as shown in FIG. 9(b), the first bottom plate 2a of the formwork main body 2 The force applied upward in the vertical direction also acts in a direction to peel off the side plates 2b, 2c from the concrete slab 16. That is, the formwork 1 for unloading opening has a structure in which the formwork main body 2 can be easily peeled off from the concrete slab 16.

Moreover, according to the formwork 1 for unloading opening, in addition to being able to be easily removed from the formwork for forming a slab after forming the concrete slab 16, the formwork body 2 and supports 6 can be reused as many times as necessary. It is possible to do so. Furthermore, as described above, when concrete is poured around the wall, the deformation of the formwork body 2 due to the pressure of concrete is suppressed by the crosspieces 5a to 5c, so the formwork 1 for loading openings has a thin wall thickness. A form body 2 can be used. In this case, the work of peeling off the form body 2 from the concrete slab 16 becomes even easier.
In this way, in the formwork 1 for unloading opening, the formwork main body 2 can be easily peeled off from the concrete slab 16, so that the work of removing the formwork main body 2 after forming the concrete slab 16 can be carried out quickly and efficiently. can.
Although it is difficult to reuse the formwork body 2 taken out from the concrete slab 16, the material cost of the formwork body 2 of the shipping opening formwork 1 is significantly lower than that of conventional metal formwork bodies. cheap. Therefore, according to the formwork 1 for the shipping opening, it is possible to form the shipping opening 17 (see FIG. 10(b)) in a part of the concrete slab 16 at low cost.

As shown in FIG. 11(a), the pipe fixing member 18 has a rectangular shape in a plan view, and a cylindrical pipe support portion 18b stands at the center of one side of a base 18a, which has screw insertion holes 19 at the four corners. It has a built-in structure. In step S10, as shown in FIGS. 10(a) and 10(b), the upper ends of the columns 6 protrude from the upper surface of the concrete slab 16 at four locations around the shipping opening 17. . Therefore, in step S11, the upper end of this support 6 is used to perform opening curing (installation of a safety fence around the shipping opening 17). Specifically, first, the upper end of one support 6 is inserted into one of the screw insertion holes 19 of the base 18a, and then the pipe is fixed by tightening the nut 10 and using the other screw insertion holes 19. The member 18 is fixed at four locations around the shipping opening 17. Then, pipes (not shown) are respectively erected on the pipe support portions 18b of the four pipe fixing members 18, and a safety fence (not shown) is built around the shipping opening 17 using these four pipes. Install.

As explained above, in the method of forming the shipping opening 17 using the shipping opening form 1, when forming the shipping opening 17 in the concrete slab 16, the shipping opening form 1 described above is used. The same action and effect will be achieved.

Although the unloading opening form 1 includes a form main body 2 consisting of a pair of divided bodies 7, 7, the structure is not limited to this. For example, the pair of divided bodies 7, 7 have a shape in which the form body 2 is cut at the central portion of the first bottom plate 2a by a plane perpendicular to the first bottom plate 2a and the pair of side plates 2c, 2c. It may be something made from eggplant. Moreover, the formwork main body 2 is not constituted by a pair of divided bodies 7, 7, but can be made into an integral body.
Furthermore, the structure may be such that the crosspiece 5c is spanned over the side plates 2c, 2c instead of the side plates 2b, 2b. The number of crosspieces 5c is not limited to two, but can be changed as appropriate. Further, the crosspieces 5a and the crosspieces 5b may have the same length.

INDUSTRIAL APPLICATION This invention is applicable to the case where a shipping opening is formed in the concrete slab which becomes a floor, a ceiling, etc. in a multi-story building whose structural material is reinforced concrete or steel-frame reinforced concrete.

1... Formwork for unloading opening 2... Formwork main body 2a... First bottom plate 2b, 2c... Side plate 2d... Frame body plate 2e, 2f... Outer plate 3... Receiver 3a... Second bottom plate 3b... Outer plate 3c ...Inner plate 4...Strut fixing tool 4a...Top plate 4b...Lower plate 4c...Connection plate 5a-5c...Structure 6...Strut 6a...Outer circumferential surface 6b...Male thread part 7...Divided body 7a...End face 8a-8b...Screw fixation Hole 9a...first notch 9b...second notch 9c...third notch 10...nut 11...uneven part 12...plywood 13...screw 14...insulating material 15...slab reinforcement 16...concrete slab 17...load Output opening 18... Pipe fixing member 18a... Base 18b... Pipe support part 19... Screw insertion hole t... Thickness of the crosspiece w... Width of the crosspiece L... Distance between the upper and lower plates T... Thickness of the second bottom plate W ₁ ... Width of the second bottom plate W ₂ ... Width of the outer plate and inner plate

Claims (14)

When forming a shipping opening in a concrete slab, a formwork for a shipping opening is installed on a flat plate material that constitutes a part of the formwork for forming a slab,
A box-shaped synthetic resin formwork body with an open top, consisting of four side plates and a rectangular first bottom plate;
four first bars arranged to form a rectangular shape in plan view;
Four receivers are fixedly installed at each of the four corners of the form body on the upper end side of the side plate to hold both ends of the first bar, respectively. Formwork for opening. four pillar holding means each attached to each of the four receivers;
four struts arranged on the outside of the formwork body so as to be orthogonal to the first bottom plate, and each of which is fixed to each of the four receivers by the strut holding means; The mold for unloading opening according to claim 1, wherein the mold has a length that allows the tip end to come into contact with the flat plate material when the form body is installed on the flat plate material. frame. The pillar is provided with a male thread on its outer peripheral surface,
The strut holding means includes a strut fixing device that has a U-shape in side view and in which the receiver is disposed, and a pair of nuts;
The pillar fixing device is
an upper plate having a first through hole through which the support column is inserted;
a lower plate parallel to the upper plate and provided with a second through hole so as to communicate with the support column inserted through the first through hole;
a connection plate connecting the base end sides of the upper plate and the lower plate,
The pair of nuts are screwed onto the male screws of the support and are respectively installed above and below the upper plate and the lower plate of the support support so as to sandwich them therebetween. 2. The formwork for the unloading opening described in 2. The upper plate and the lower plate of the column fixing device are provided with a first notch and a second cutout in which the column can be placed, instead of being provided with the first through hole and the second through hole. Notches are respectively formed from the proximal end side to the distal end side, and a first notch connects the first notch and the second notch with respect to the connection plate, and allows the support column to be placed inside. 4. The formwork for an unloading opening according to claim 3, wherein the notches 3 are formed in a direction perpendicular to the upper plate and the lower plate. The receiver is
a second bottom plate having an L-shape in plan view;
It has an L-shape in side view and consists of an outer plate and an inner plate that extend vertically in the same direction from the outer edge and inner edge of the second bottom plate, respectively,
Claims 1 to 4, wherein the second bottom plate, the outer plate, and the inner plate form a groove in which an end of the first bar is disposed. The formwork for an unloading opening according to any one of the items. The formwork main body includes a frame plate having a rectangular shape in plan view and extending outward from the upper ends of the four side plates in parallel with the first bottom plate,
The formwork for an unloading opening according to any one of claims 1 to 4, wherein the receiver is fixed to the frame plate. 7. The load according to claim 6, wherein the form body has four outer plates that are rectangular in plan view and extend vertically upward from the outer edge of the frame body plate. Formwork for opening. According to any one of claims 1 to 4, wherein the side plate of the form body has a trapezoidal shape in which the upper end side is shorter than the lower end side when viewed from above. Formwork for unloading opening as described. The mold for an unloading opening according to any one of claims 1 to 4, wherein at least a portion of the mold body is provided with an uneven portion having a wave-shaped cross section. frame. The formwork for an unloading opening according to any one of claims 1 to 4, wherein the formwork body is formed of a transparent member. Claims 1 to 4 are characterized in that a second bar is provided so as to span orthogonally to the two first bars arranged parallel to each other. The formwork for an unloading opening according to any one of the above. The formwork body consists of a pair of divided bodies,
The divided body has a shape in which the formwork body is cut at a central portion of the first bottom plate by a plane perpendicular to the first bottom plate and the pair of side plates that are parallel to each other. The formwork for an unloading opening according to any one of claims 1 to 4, characterized in that: A method of forming the shipping opening in the concrete slab using the shipping opening form according to claim 1, comprising:
fixing the form body on the flat plate material that constitutes a part of the slab forming form;
fixing the four receivers one by one at each of the four corners of the form body on the upper end side of the side plate;
A method for forming a shipping opening, comprising the step of fixing four first rods to the form body so that both ends of the rods are held by the receivers, respectively. . a step of attaching four pillar holding means one by one to each of the four receivers fixed to the form body;
arranging four pillars on the outside of the form body so that they are perpendicular to the flat plate material and their tips are in contact with the flat plate material;
14. The method for forming a shipping opening according to claim 13, further comprising the step of fixing the four pillars one by one to the receiver via the pillar holding means.

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