JP2010095969A - Construction method of void slab and hollow wall, and void slab and hollow wall constructed by the construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a void slab simple in structure and easy to construct. <P>SOLUTION: Hollow forming members 10 are put to receiving parts 2 of a temporary form 1 to pour unhardened concrete C, and the concrete C is hardened while maintaining contact between the hollow forming members 10 and the receiving parts 2 to form a half PC plate 11. The temporary form 1 is removed from the half PC plate 11, and unhardened concrete C is poured to the temporary form removed side of the half PC plate 11. The concrete C is hardened and integrated with the half PC plate 11. Since the temporary form 1 is exposed to the outside in placing the first concrete C, the temporary form 1 is easily removed after the concrete is hardened. When the concrete C on the opposite side is placed, the hollow forming members 10 are immobile with the concrete C placed previously, that is, this method makes it easy to maintain the positions of the hollow forming members 10 in the void slab B and achieves simple structure and easy construction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for constructing a void slab and a hollow wall of a building, and a void slab and a hollow wall constructed by the construction method.

  Various types of void slabs and hollow walls are employed to reduce the weight of concrete slabs in buildings.

  For example, as shown in FIG. 4, the void slab is formed by embedding a hollow forming member (a so-called “void formwork”) made of a hollow or foamed material in concrete. The weight per unit volume of the concrete slab is reduced by interposing a lightweight hollow forming member in the concrete.

  Some of these void slabs, which were built by factory production, may be brought to the site and used, or the void slabs can be removed by constructing the formwork, placing bars, placing concrete, etc. at the site. Sometimes build.

  The construction method is such that, for example, as shown in a void slab B shown in FIG. 6, the upper end 3a, the lower end 3b, etc. are arranged in the concrete mold, and the void is formed between the upper end 3a and the lower end 3b. A hollow forming member 10 called a formwork is arranged. Further, reinforcing bars 3c may be provided around the hollow forming member 10 as necessary.

  In this state, uncured concrete C is poured into the concrete formwork, and the concrete C is cured. At this time, the buoyancy due to the uncured concrete C is generated in the hollow forming member 10, but the upper end reinforcement 3a and the like are positioned immediately above the hollow forming member 10 to prevent the lifting (Patent Document). 1 and 2).

  Also, another roofing material with a corrugated cross section is bolted onto a half PC (precast) plate that integrally fixes a corrugated cross section roof material to the upper surface of the reinforced concrete member, and reinforcement and concrete placement are placed on it. The technique of the concrete slab which goes and makes the space pinched | interposed by the roof material into a hollow part is also disclosed (refer patent document 3).

JP 2004-3297 A JP 2005-282010 A JP 11-256742 A

According to the void slabs of Patent Documents 1 and 2 and the method for constructing the void slab, uncured concrete enters below the hollow forming member when the concrete is placed, so that buoyancy acts on the hollow forming member.
For this reason, each part of the hollow forming member is pressed by an upper end line or the like so that the hollow forming member does not float up.

  However, since the hollow forming member is embedded and fixed in the concrete of the void slab, there is a problem that the shape and bar arrangement structure of the hollow forming member are complicated in order to suppress the floating of the hollow forming member. It is desirable that the hollow forming member and the bar arrangement structure are simple.

  Moreover, according to the void slab of patent document 3, and the construction method of the void slab, since a hollow formation member is comprised with two roof materials, it is necessary to fix the roof materials with bolts. Such fixing work is complicated.

  Then, this invention makes it a subject to set it as the construction method of the void slab and hollow wall which are simple and easy to construct, and the void slab and hollow wall.

  In order to solve the above-mentioned problem, the present invention forms a receiving part on the bottom surface of the temporary mold frame, places a hollow forming member on the receiving part and casts concrete into the temporary mold frame, While maintaining the contact between the hollow forming member and the receiving part, the concrete is cured to form a half PC plate, the temporary mold frame is removed from the half PC plate, and the temporary mold frame of the half PC plate is removed. A method of constructing a void slab was adopted in which concrete was placed on the other side, the concrete was cured, and integrated with the half PC plate.

  That is, in this method, first, concrete is cast on the side where the hollow forming member is disposed with the temporary mold interposed therebetween, and then the concrete is hardened and then the temporary mold is removed and the concrete is cast on the opposite side.

Since the temporary formwork is exposed to the outside in the first concrete placement, even if the contact between the temporary formwork and the hollow forming member is maintained until the concrete is hardened, the hollow forming member is made into concrete by the concrete hardening. After being embedded, the temporary form frame can be easily removed. In addition, when the concrete is placed on the opposite side, the hollow forming member is already fixed so as not to move by the concrete that has been placed first, so that no lifting or the like will occur in the concrete placement that will be performed later. It has become.
That is, according to this method, it is easy to maintain the position of the hollow forming member in the void slab, and the shape and the bar arrangement structure of the hollow forming member are not complicated.

In addition, when placing concrete with the temporary mold frame facing upward, when placing the concrete in the temporary mold frame, the hollow forming member is placed on the receiving portion. The portion has a shape that makes a close surface contact with the bottom surface of the hollow forming member, and can adopt a configuration in which concrete does not enter between the contact surfaces of the receiving portion and the bottom surface of the hollow forming member.
If concrete does not enter between the contact surfaces of the receiving portion and the hollow forming member, buoyancy can be prevented from acting on the hollow forming member, and even if it acts, the buoyancy can be minimized. If the buoyancy does not act on the hollow forming member or if the buoyancy is small, the shape and the bar arrangement of the hollow forming member can be simplified.

  Moreover, the said receiving part can employ | adopt the structure which contacts the whole downward surface of the said hollow formation member. In this way, a state in which no buoyancy acts on the hollow forming member can be realized.

Furthermore, the structure which provided the removal prevention means for maintaining the contact with the said hollow formation member and the said receiving part to the said temporary form frame until hardening of the said concrete is employable. If it does in this way, since the hollow formation member does not move with respect to a temporary formwork in the first concrete placement, the accuracy of the position of the hollow formation member in a void slab can be raised.
This disengagement prevention means is effective not only when placing concrete with the temporary form frame facing upward, but also when placing concrete with the sideways and facing downward.
In the above-described configuration, the detachment preventing means can be omitted if the buoyancy acting on the hollow forming member is small or if the buoyancy does not act at all.

  As the separation preventing means, it is possible to adopt a configuration that is an adhesive that adheres the hollow forming member and the receiving portion. Alternatively, as a detachment preventing means, a bolt or a screw that joins the hollow forming member and the receiving portion, and the bolt or screw is used when the temporary form frame is removed from the half PC plate. It is possible to employ a configuration in which the coupling with the forming member can be released. Moreover, the structure which is a reinforcing bar which presses the said hollow formation member so that it may not leave | separate from the said receiving part can be employ | adopted as a removal prevention means. These separation preventing means can be used in combination with a plurality of means.

  It is possible to adopt a configuration in which unevenness is formed on the bottom surface of the temporary mold frame and a shear cotter is formed on the surface of the half PC plate on the side from which the temporary mold frame is removed. Further, it is possible to adopt a configuration in which unevenness is formed on the bottom surface of the hollow forming member and the unevenness is a sheer cotter. If it does in this way, the integrity of the concrete (half PC board) cast previously and the concrete cast later can be improved.

  In addition, when placing concrete on the side of the half PC plate from which the temporary form frame has been removed, a plurality of the half PC plates are arranged in parallel, and after arranging the reinforcing bars straddling the half PC plates in parallel, A method for constructing a void slab for integrating the concrete and the parallel half PC plates by placing concrete on the side of the half PC plates in parallel where the temporary form frame has been removed and curing the concrete. Can be adopted.

  In this way, when building a building with a large number of half PC plates in advance, it is possible to build a void slab by integrating these half PC plates all at once. Can contribute.

In addition, the hollow wall which stands | starts up from a floor board can also be constructed | assembled using the said half PC board.
That is, a receiving part is formed on the bottom surface of the temporary mold frame, a hollow forming member is placed on the receiving part, concrete is placed in the temporary mold frame, and the hollow forming member and the receiving part are brought into contact with each other. The concrete is cured while maintaining to form a half PC plate, the temporary mold frame is removed from the half PC plate, and the side of the half PC plate from which the temporary mold frame is removed is directed to the same side, and a plurality of The half PC plates are placed side by side on a floor plate, and concrete is placed on the side of the half PC plates from which the temporary form frame has been removed, and the concrete is cured, whereby the concrete and the parallel are placed. It is a construction method of a hollow wall that integrates half PC plates.

  The present invention can be a void slab and a hollow wall having a simple structure and easy construction, or a method for constructing the void slab and the hollow wall.

  Embodiments of the present invention will be described with reference to the drawings. 1 (a) to 1 (d) show a process of manufacturing a half PC plate 11 using the temporary mold frame 1, the hollow forming member 10, the reinforcing bar 3 and the like, and FIGS. The process of constructing void slab B as a floor board of a building using a plurality of PC boards 11 is shown.

  As shown in FIG. 1A, a temporary mold frame 1 formed by bending a steel plate having a uniform thickness by pressing or the like is used for the production of the half PC plate 11. The temporary form frame 1 has receiving portions 2 formed at regular intervals on the bottom surface thereof. As shown in FIG. 3, the receiving portion 2 extends long in a certain direction with an equal width, and all of the receiving portions 2 are provided in parallel. Moreover, the upper surface 2a of the receiving part 2 is a concave arcuate surface.

  Between the adjacent receiving part 2 and the receiving part 2, a sheer cotter forming part 4 is slightly lower than the receiving part 2.

  As shown in FIG. 4A, the shear cotter forming portion 4 protrudes downward along the inclined portion 4a from the width direction edge 2b of the receiving portion 2, and extends in the lateral direction from the lower end of the inclined portion 4a. It passes through 4b and is connected to the lower end of the inclined portion 4a extending from the widthwise edge 2b of the adjacent receiving portion 2. In this embodiment, the base part 4b is comprised by the flat horizontal surface.

  On the receiving portion 2, a hollow forming member 10 called a void form is placed. In this embodiment, as the hollow forming member 10, as shown in FIG. 3, a pipe (cylindrical member) having a hollow elliptical cross section is employed.

  The pipe is not limited to the elliptical cross section of this embodiment, and may be, for example, a circular cross section or a rectangular cross section. Moreover, when employ | adopting a pipe, the winding pipe which wound the strip | belt-shaped steel plate helically and the pipe which wound the steel plate cylindrically can be employ | adopted, for example.

  As shown in FIG. 1A, a hollow forming member 10 is placed on the receiving portion 2 of the temporary mold 1. The upper surface 2a of the receiving portion 2 is a concave arcuate surface, and the upper surface 2a is in close contact with the bottom surface 10a of the hollow forming member 10 (see the enlarged view of FIG. 4A). .

  As shown in FIG. 1 (b), the reinforcing bars 3 are arranged vertically and horizontally so as to hang over the hollow forming member 10. The vertical and horizontal rebars 3 are bound together at a lattice point by a number line or the like. In addition, you may connect the temporary formwork 1 and the reinforcing bar 3 as needed (refer the connection member 5 of FIG. 5).

  As shown in FIG. 1C, concrete C is placed in the temporary mold frame 1. At this time, when pouring uncured concrete C, the bottom surface 10a of the hollow forming member 10 is in close contact with the upper surface 2a of the receiving portion 2, so that the receiving portion 2 and the hollow forming member 10 are in contact with each other. Concrete C does not enter between the contact surfaces of the bottom surface 10a. For this reason, the buoyancy acting on the hollow forming member 10 is slight, and the concrete C can be hardened while maintaining contact between the hollow forming member 10 and the receiving portion 2.

  In addition, as shown in FIG.4 (b), you may make it the receiving part 2 contact the whole downward surface of the said hollow formation member 10. FIG. If the downward surface of the hollow forming member 10 is completely covered, generation of buoyancy can be eliminated.

Moreover, in this embodiment, since the connecting member 5 that connects the reinforcing bar 3 and the temporary mold frame 1 is provided, the reinforcing bar 3 and the connecting member 5 are separated from the receiving part 2 by the hollow forming member 10. It functions as a detachment prevention means that can be held down.
Even if the reinforcing bar 3 is not provided with the connecting member 5, the hollow forming member 10 is pressed by its own weight so as not to be separated from the receiving portion 2, so that it itself functions as a detachment preventing means. You can also.

  After the concrete C is cured, as shown in FIG. 1 (d), the temporary form frame 1 is removed, and the concrete C, the reinforcing bar 3 and the hollow forming member 10 become an integral half PC plate 11.

  When removing the temporary mold frame 1, when the connecting member 5 is used, the temporary mold frame 1 and the connecting member are connected from the back side of the temporary mold frame 1 (the side opposite to the side where the hollow forming member 10 is provided). 5 is cut off. For example, as shown in FIG. 5, when the connecting member 5 is a bolt shaft 5 a and a nut 5 b, the nut 5 b is loosened from the back side of the temporary mold frame 1 to separate the bolt shaft 5 a and the temporary mold frame 1. Depending on the configuration of the connecting member 5, the connecting portion between the connecting member 5 and the temporary mold 1 may be cut.

  In addition, if the lightweight concrete is employ | adopted as the said concrete C to be cast in the said temporary formwork 1, the half PC board 11 can be reduced in weight. If the half PC board 11 is lightweight, it is advantageous for transportation and lifting, and a structural member that supports the board can be downsized to reduce costs.

  The half PC board 11 can be manufactured at the site where the building is actually constructed. Usually, the half PC board 11 is manufactured at the factory, and the half PC board 11 is used on the site. It is efficient to carry in the following work.

The half PC board 11 is carried to the site, and the construction of the floor board is started. As shown in FIG. 2 (a), the half PC plate 11 is placed on the surface from which the temporary mold frame 1 is removed, and a plurality of the half PC plates 11 are provided as shown in FIG. 2 (b). Run in parallel between the beams of the structure.
At this time, the reinforcing bars 3 are arranged between the half PC plates 11 arranged in parallel. As shown in FIG. 2B, the reinforcing bars 3 are continuously arranged vertically and horizontally across the parallel half PC plates 11 so as to hang over the hollow forming member 10. The reinforcing bars 3 are bound together by a number line or the like at lattice points.

  Further, the reinforcing reinforcing bars 6 are disposed across the recess 12 provided at the end of the half PC plate 11 and the recess 12 provided at the end of another half PC plate 11 adjacent to the half PC plate 11. Has been. This reinforcing bar 6 is provided at a position close to the reinforcing bar 3 already embedded in the half PC plate 11.

  Concrete C is placed on the half PC plate 11. When the placed concrete C is cured, the concrete C and the half PC plates 11 arranged in parallel are integrated with each other, as shown in FIG.

  At this time, since the shear cotter forming portion 4 is provided on the bottom surface of the temporary mold frame 1, the temporary mold frame 1 of the half PC plate 11 is formed by the unevenness of the shear cotter forming portion 4 and the receiving portion 2. A shear cotter is formed on the surface from which the is removed. For this reason, the adhesion performance of the half PC board 11 and the concrete C laid later is enhanced, and the integrity is improved.

In addition, an unevenness | corrugation can be formed in the bottom face 10a of the said hollow formation member 10, and the unevenness | corrugation can also be used as a sheer cotter. Since the bottom surface 10a of the hollow forming member 10 is exposed on the surface of the half PC plate 11 after the provisional mold frame 1 is removed, if an unevenness is provided on the exposed bottom surface 10a, it is placed later. The adhesion performance with the concrete C to be improved is improved.
Further, if the base 4b of the sheer cotter forming part 4 is provided with irregularities, the sheer cotter formed on the surface of the half PC plate 11 is increased, and the adhesion performance is further improved.

  In addition, in this embodiment, although the pipe (cylindrical member) was used as the hollow forming member 10, in addition to such a cylindrical hollow forming member 10, it was molded into an arbitrary shape such as a sphere, a rectangular parallelepiped, or a cube. You may employ | adopt the hollow formation member 10 which consists of a hollow or a foam. As the material, for example, polystyrene foam can be employed.

  Moreover, in this embodiment, although the method of integrating the some half PC board 11 was employ | adopted by placement of the concrete C after removing the temporary formwork 1 (placement of the concrete C performed later), A single piece of void slab B can be separately manufactured for one half PC plate 11 by separately placing concrete C to be performed later on the PC plate 11.

  Moreover, in these embodiments, the process of constructing the void slab B as the floor board of the building has been shown, but in addition to this, when constructing the wall portion of the hollow wall structure connecting the upper and lower floor boards, The construction method of the void slab B can be adopted.

  When constructing a hollow wall, a plurality of the half PC plates 11 are fixed in parallel on a floor plate already constructed. Each half PC board 11 is arranged side by side in the horizontal direction along the position where the wall portion is provided and, if necessary, in the vertical direction, with the side from which the temporary mold frame 1 has been removed facing the same side. Each half PC board 11 is fixed so that it may not move with respect to a floor board in the state which connects between floor boards.

  After the necessary reinforcing bars 3, reinforcing reinforcing bars 6 and the like are arranged between the fixed half PC plates 11, the mold frames are arranged along the side where the temporary mold frames 1 of the parallel half PC plates 11 are removed. . With this formwork, one wall surface of the hollow wall is formed. The other wall surface is already formed by the concrete surface of the half PC plate 11.

  By placing concrete C in the formwork and hardening the concrete C, the concrete C, the half PC plates arranged in parallel, and the floor plate are integrated to form a hollow wall.

As a method of fixing the half PC board 11 and the floor board, for example, a reinforcing bar is embedded in the lower floor board so that the upper end of the reinforcing bar protrudes from the upper surface of the floor board, and the reinforcing bar is connected to the half PC board. You may make it insert in the hole provided in the lower end surface of 11. Further, a reinforcing bar may be embedded in the upper floor plate so that the lower end of the reinforcing bar protrudes from the lower surface of the floor plate, and the reinforcing bar is inserted into a hole provided in the upper end surface of the half PC plate 11. .
As another method, the upper end of the reinforcing bar embedded in the floor board is projected into a mold forming one wall surface of the hollow wall, and then the reinforcing bar and the half PC are formed by placing and hardening the concrete. The board 11 and the floor board may be integrated.

(A)-(d) is explanatory drawing which shows the construction method of the half PC board of one Embodiment. (A)-(c) is explanatory drawing which shows the construction method of the void slab of the embodiment The perspective view which shows the principal part of a temporary formwork (A) (b) is explanatory drawing which shows the contact state of a temporary form frame and a hollow formation member The principal part enlarged view which shows the example at the time of using a connection member Cross section of conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Temporary form frame 2 Receiving part 2a Upper surface 3 Reinforcing bar 4 Shear cotter formation part 4a Inclination part 4b Base part 5 Connection member 6 Reinforcement reinforcing bar 10a Bottom formation member 10a Bottom face 11 Half PC board 12 Recessed part B Void slab C Concrete

Claims (13)

  A receiving part (2) is formed on the bottom surface of the temporary mold frame (1), a hollow forming member (10) is placed on the receiving part (2), and the concrete (C) is placed in the temporary mold frame (1). The concrete (C) is hardened while maintaining the contact between the hollow forming member (10) and the receiving part (2) to form a half PC plate (11), and the half PC plate (11 ) Remove the temporary formwork (1), place concrete (C) on the side of the half PC plate (11) from which the temporary formwork (1) is removed, and harden the concrete (C). A method for constructing a void slab integrated with the half PC board (11).   When placing concrete (C) in the temporary mold frame (1), the hollow forming member (10) is addressed on the receiving part (2), and the receiving part (2) The shape is in close contact with the bottom surface (10a) of the hollow forming member (10), and the concrete (C) is between the contact surface of the receiving portion (2) and the bottom surface (10a) of the hollow forming member (10). The void slab construction method according to claim 1, wherein the void slab is not allowed to enter.   The method for constructing a void slab according to claim 2, wherein the receiving portion (2) is in contact with the entire downward surface of the hollow forming member (10).   The temporary mold frame (1) is provided with detachment preventing means for maintaining contact between the hollow forming member (10) and the receiving part (2) until the concrete (C) is cured. The void slab construction method according to any one of claims 1 to 3.   5. The method for constructing a void slab according to claim 4, wherein the separation preventing means is an adhesive that adheres the hollow forming member (10) and the receiving portion (2).   The detachment prevention means is a bolt or a screw that couples the hollow forming member (10) and the receiving portion (2), and the bolt or screw is connected to the temporary mold frame (1) from the half PC plate (11). The method for constructing a void slab according to claim 4, wherein the connection between the receiving portion (2) and the hollow forming member (10) can be released when the) is removed.   5. The void slab construction method according to claim 4, wherein the detachment preventing means is a reinforcing bar that presses the hollow forming member (10) so as not to leave the receiving portion (2).   An unevenness is formed on the bottom surface of the temporary mold frame (1), and a shear cotter is formed on the surface of the half PC plate (11) from which the temporary mold frame (1) has been removed. The void slab construction method according to any one of claims 1 to 7.   The method for constructing a void slab according to any one of claims 1 to 8, wherein irregularities are formed on a bottom surface (10a) of the hollow forming member (10), and the irregularities are used as a shear cotter.   When placing concrete (C) on the side of the half PC plate (11) from which the temporary form frame (1) is removed, a plurality of the half PC plates (11) are arranged in parallel, and the half PCs arranged in parallel are arranged. After arranging the reinforcing bars straddling between the plates (11), concrete (C) is placed on the side of the half PC plates (11) arranged in parallel on the side from which the temporary form frame (1) is removed, and the concrete (C) The method for constructing a void slab according to any one of claims 1 to 9, wherein the concrete (C) and the half PC plates (11) arranged in parallel are integrated by curing.   A void slab constructed by the void slab construction method according to claim 1.   A receiving part (2) is formed on the bottom surface of the temporary mold frame (1), a hollow forming member (10) is placed on the receiving part (2), and the concrete (C) is placed in the temporary mold frame (1). The concrete (C) is hardened while maintaining the contact between the hollow forming member (10) and the receiving part (2) to form a half PC plate (11), and the half PC plate (11 The temporary mold frame (1) is removed, and the half PC plate (11) is placed on the floor plate with the side of the half PC plate (11) from which the temporary mold frame (1) is removed facing the same side. The concrete (C) is placed on the side of the half PC plate (11) from which the temporary formwork (1) is removed, and the concrete (C) is hardened. Integrating concrete (C) and the half PC plates (11) in parallel Method for constructing a hollow wall with symptoms.   The hollow wall constructed | assembled by the construction method of the hollow wall of Claim 12.

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