JP4312110B2 - Two-way concrete void slab - Google Patents

Description

  The present invention relates to a two-way concrete void slab in which lightweight void molds are arranged in a grid pattern between upper and lower ends, a method for constructing the same, and the lightweight void molds used for the construction.

As this type of two-way concrete void slab, for example, as shown in FIG. 4, upper floor bars 2 are arranged in a grid pattern on floor mold 1 and lower bar bars 3 are also arranged in a grid pattern. There is a structure in which a lightweight void mold 4 made of foamed resin or the like is disposed in each grid-like space S and concrete is cast (see Patent Document 1). In the figure, reference numeral 5 denotes an auxiliary bar that is stretched over the upper and lower end bars 2 and 3 to suppress the upper and lower surfaces of each void mold frame 4 and prevent its lifting.
JP 2003-321894 A

In the construction of this two-way concrete void slab, the lightweight void form 4 is generally rectangular in shape as shown in FIG. (See FIG. 13). If the front and rear, left and right directions of each lightweight void form 4 are not aligned, the strength design of the two-way concrete void slab will be distorted, so care must be taken when arranging each lightweight void form 4 so that the directions are aligned. There is.
As a technique for reducing this attention, there is a technique in which the lightweight void mold 4 is made into a sphere (a perfect sphere) and the direction of the front, rear, left and right is eliminated (see FIG. 4 of Patent Document 1).

  Since the spherical lightweight void form 4 has no direction in the vertical direction and no direction in the entire periphery, it is not necessary to consider the direction at all in its arrangement. However, since there is no directionality in the entire periphery, it is easy to move in each grid-like space S, and the fixing means is complicated. For example, in the prior art, a pressing metal fitting is fitted into the lightweight void form frame 4 from above to prevent the movement (see Patent Document 1 FIG. 4).

  An object of the present invention is to enable positioning of the lightweight void form 4 with a simple structure.

In order to achieve the above object, the present invention forms a lightweight void form by cutting the top and bottom of a sphere with parallel surfaces.
If the top and bottom of the sphere are cut off by parallel planes, the lightweight void mold can be stably placed on the slab mold with the cut bottom surface.
Moreover, the lightweight void formwork after the placement can be easily prevented from coming off from each grid-like space S by, for example, applying a fixed supporting rod to the upper end stripe on the cut upper surface. Yes, workability is also good. In addition, since the lightweight void formwork has a circular plan view, there is no front / rear / right / left directionality.

  In the present invention, since the lightweight void form has a shape obtained by cutting the top and bottom of the sphere with parallel planes, there is no directionality in each grid-like space S, and the placement work becomes easy.

As one embodiment of the present invention, a grid-like lower end line is provided in parallel with a gap in the vertical direction like the grid-like upper end line, and a lightweight void form frame is formed in each space surrounded by the grid-like upper and lower line stripes. is arranged loaded, in the light void formwork concrete is used in two directions concrete void Slab which are pouring together when a shape obtained by cutting the upper and lower sphere parallel plane, in the space from the top of the space It is possible to adopt a configuration in which a support rod fixed to the upper end muscle hits the cut upper surface to prevent it from coming out after loading.
At this time, the “size that can be loaded into the space from the top of the space” is not only the size that can smoothly enter the space from the top, The size that can be entered into the space with some kind of contrivance.

  Normally, a certain slab thickness is required between the upper and lower surfaces of the lightweight void mold and the upper and lower surfaces of the slab, so the height of the lightweight void mold is limited to a certain level, whereas the lightweight void mold In the horizontal direction, an arbitrary length is required from the relationship of the slab strength, and in general, it becomes longer with respect to the height. For this reason, when the sphere is a perfect sphere, it is difficult to meet the demand, and if the sphere has an elliptical cross section, the length in the lateral direction with respect to the height of the lightweight void frame is increased (flat shape). Therefore, it is easy to meet that demand.

  Further, in a concrete slab, vibration from the upper floor is likely to resonate in a thin and uniform thickness portion of the concrete portion. For this reason, if the lightweight void mold is formed with a recess in the middle of the cut upper surface, the thin concrete portion on the upper surface of the lightweight void mold is composed of a plurality of parts having different thicknesses (the entire area). The vibration from the upper floor is less likely to resonate, and the sound transmission is reduced by the diffusion of vibration sound on the wall surface of the recess, resulting in a quiet concrete slab. it can.

  Furthermore, if the convex part is formed in the middle of the concave part, the diffusion of the vibration sound from the upper floor on the wall surface of the convex part is added, and the diffusion effect of the vibration sound is improved. A quiet concrete slab can be obtained, and a fixed support rod can be applied to the upper end of the upper surface of the convex portion, so that the lightweight void form can be supported more reliably.

  In the same manner as in the past, these lightweight void molds have grid-like lower end bars parallel to each other in the vertical direction as well as the grid-like upper end stripes. The two-way concrete void slab can be configured such that the support rod fixed to the upper end muscle hits the cut upper surface to prevent the lightweight void formwork from coming off.

In this configuration, because the lightweight void formwork is not positioned at the lower surface level, when the lightweight void formwork is placed on the slab formwork, it may be placed directly on the formwork, in which case It is lifted by the buoyancy caused by the placement of concrete, and the upper surface of the upper end of the concrete is positioned against the fixed support rod. At this time, it is preferable to provide a guide for raising the lightweight void form so that the ascending is smooth and sure.
Positioning of the lightweight void formwork at the lower surface level is possible, for example, by providing a support rod also on the lower end bar and applying a support bar fixed to the support bar and upper end bar to the upper and lower surfaces cut out of the lightweight void formwork. It can be carried out by supporting the mold frame.

In order to construct these two-way concrete void slabs, for example, slab molds are provided with grid-like bottom bars parallel to each other in the same vertical direction as the grid-like top bars, and support rods are fixed to the bottom bars. After placing each of the lightweight void molds on the support rod through the lower surface in each space surrounded by the upper and lower stripes of the lattice shape, the support collar is applied to the upper surface of the lightweight void mold frame. further fixed outside, by the two support rods, after preventing the escape from the space across the lightweight void mold, employing a method such that concrete is.

FIG. 1 to FIG. 3 show an embodiment, and the void form frame 40 of this embodiment is made of a solid foamed resin, and as shown in FIG. It has a shape cut by the surface. The size of the top surface 41 and bottom surface 42 is set at by Uni appropriate that obtained support without wants against the supporting rod below moves voids mold 40. For example, the diameter of the upper surface 41 and the lower surface 42 is 231.5 mm. Further, the diameter of the sphere (the size of the void form frame 40) is also set as appropriate, for example, with a diameter of 350 mm, etc., so that it can be fitted obliquely into the space S described later. Furthermore, the height H of the void mold 40 is appropriately determined according to the slab thickness, and is, for example, a value obtained by subtracting 100 mm from the slab thickness.

As shown in FIGS. 1 and 2, the void mold 40 is provided with upper and lower lower bars 2 and 3 on the floor mold 1, and in the front-rear direction in the middle of the left and right of the lower bars 3. After the reinforcing bar support rod 12 is welded and fixed, the void form 40 is fitted into the square space S in a grid pattern that coincides vertically between the upper and lower reinforcing bars 2, 3, and the lower surface 42 is fixed. And placed on the support rod 12. Thereafter, the reinforcing bar 11 made of the left and right bars is fixed to the upper surface 41 of the void form frame 40 by being welded to the upper surface 41 of the void form frame 40 and fixed to the middle of the upper end bars 2. After supporting and fixing the upper and lower sides, auxiliary bars and the like are arranged as necessary, concrete C is placed, and a two-way concrete void slab is constructed. For fixing the support rods 11 and 12 to the upper and lower end bars 2 and 3, various means such as a wire can be employed instead of welding.

  As shown in FIG. 3B, if the concentric circular recess 43 is formed in the middle of the cut upper surface 41 as shown in FIG. 3B, vibration from the upper floor hardly resonates. Thus, a quiet concrete slab can be obtained by the diffusion of vibration sound on the wall surface of the recess 43. Furthermore, as shown in FIG. 5C, a concentric circular convex portion 44 may be formed in the middle of the concave portion 43. If this convex portion 44 is formed, diffusion of vibration sound from the upper floor on the wall surface of the convex portion 44 is added, the diffusion effect is improved, and a quieter concrete slab can be obtained. Since the fixed support rod 11 can be applied to the upper end muscle 2 on the upper surface of the convex portion 44, the lightweight void form frame 40 can be more reliably supported.

Schematic perspective view of one embodiment Cut front view of the same embodiment The perspective view of each example of the void formwork of the Example Schematic perspective view of a conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Floor form frame 2 Upper end reinforcement 3 Lower end reinforcement 11, 12 Support rod 40 Void mold frame 41 The cut-out upper surface 42 of a void mold frame The cut-out lower surface 43 of a void mold frame Recessed part 44 Convex part S Grid-like space

Claims (7)

Similar to the lattice-shaped upper end line (2), the lattice-shaped lower end line (3) is provided in parallel in the vertical direction with a space therebetween, and in each space (S) surrounded by the lattice-shaped upper and lower end lines (2, 3). The lightweight void formwork (40) used in a two-way concrete void slab in which a lightweight void formwork (40) is arranged and concrete (C) is placed,
Both the a shape obtained by cutting the upper and lower sphere parallel surfaces, a the space (S) can be loaded size in the upper part of the space (S), and after its loading, to the upper end muscle (2) A lightweight void formwork for a two-way concrete void slab in which a fixed support rod (11) hits the cut upper surface (41) to prevent it from coming off.   The lightweight void formwork for a two-way concrete void slab according to claim 1, wherein the spherical body has an elliptical cross section.   The lightweight void formwork for two-way concrete void slabs according to claim 1 or 2, wherein a recess (43) is formed in the middle of the cut upper surface (41).   The lightweight void formwork for a two-way concrete void slab according to claim 3, wherein a convex portion (44) is formed in the middle of the concave portion (43) formed in the middle of the cut upper surface.   Similar to the lattice-shaped upper end line (2), the lattice-shaped lower end line (3) is provided in parallel in the vertical direction with a space therebetween, and in each space (S) surrounded by the lattice-shaped upper and lower end lines (2, 3). 5. The lightweight void formwork (40) according to any one of claims 1 to 4, wherein the lightweight void formwork (40) is cut by the support bar (11) fixed to the upper end line (2). A two-way concrete void slab that hits the top surface (41) and prevents it from coming out. Also provided support rod (12) to the lower end muscle (3), its the support rod (12) and the upper muscle (2) to secure the support rod (11) and by the lightweight void mold (40) 6. The two-way concrete void slab according to claim 5, wherein the two-way concrete void slab is supported by being sandwiched through the cut upper and lower surfaces (41, 42) . A method of constructing a bi-directional concrete void slab according to claim 6,
The slab formwork (1) is provided with the lattice-shaped lower end bars (3) in parallel with the upper and lower lines in the same manner as the lattice-shaped upper end lines (2), and the support rods (12) are provided on the lower end lines (3). A lightweight void mold (40) is placed on the support rod (12) via its lower surface (42) in each space (S) surrounded by upper and lower streak (2, 3) in a lattice shape. After that, the support rod (11) is fixed to the upper end line (2) by being applied to the upper surface (41) of the lightweight void form frame (40) , and the light weight is obtained by the both support rods (11, 12). A method for constructing a two-way concrete void slab, wherein concrete (C) is placed after preventing the void form (40) from slipping out of the space (S).

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