JP3267586B2 - Formwork and concrete slabs for embedding hollow concrete slabs - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enough prevent noise in a wide frequency region with a small amount of concrete used. SOLUTION: This form presents a laid-flat box shape including a space part 5 formed by surrounding with a top plate part 1a and a vertical plate part 1b with the lower surface opened. A columnar pipe body 12 having a through-hole 2 formed to pierce from the upper surface of the top plate part 1a to the lower surface of the space part 5 for filling concrete is provided below the top plate part 1a. The pipe body 12 is disposed at a space from the vertical plate part 1b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a formwork for embedding a hollow concrete slab having a space with an open lower surface, and a concrete slab.

[0002]

2. Description of the Related Art Concrete floor boards (concrete slabs) used for building structures such as condominiums and apartment buildings and office buildings have a predetermined floor impact sound grade in order to prevent the occurrence of noise problems on the upper and lower floors. Designed and constructed to satisfy. In designing and constructing concrete slabs, in recent years, hollow concrete slabs in which a hollow part is formed by burying a formwork in concrete have a sound insulation performance equal to or higher than that of a slab made of only concrete, and Since it is possible to realize cost reduction and weight reduction by reducing the amount, it is attracting attention as a suitable slab, and is partially used in practice.

[0003] Conventionally, a hollow concrete slab form has been designed to reduce the noise caused by the resonance phenomenon by focusing on the fact that a resonance phenomenon occurs with the width dimension of the hollow portion as a unit span. (Japanese Patent Laid-Open No. Hei 1
-284667). Specifically, FIG. 22 and FIG.
As shown in FIG. 5, a mold body 51 made of a synthetic resin is formed in a rectangular shape, a plurality of recesses 51a are formed in the mold body 51 at equal intervals, and a slit 51b is formed between these recesses 51a. Has been proposed so as to communicate with upper and lower surfaces.

[0004] According to the above configuration, after placing the form body 51 on the half-PC board and then casting the cast-in-place concrete, a hollow portion can be formed by the concave portion 51a and the slit 51b. The hollow concrete slab in which the cast-in-place concrete and the half-PC board are joined by the concrete poured into the inside can be obtained. Further, by limiting the width dimension of the concave portion 51a with concrete in the slit 51b, a resonance phenomenon in units of the concave portion 51a (hollow portion) can be suppressed, and noise reduction due to this phenomenon can be realized. .

[0005]

However, focusing on the relationship between the width of the hollow portion and the resonance phenomenon, a slit 51b having a narrow communicating portion formed between the recessed portions 51a is arranged as in the prior art. In a configuration that reduces noise by
It is necessary to set the width dimension of the recess 51a according to the wavelength of the noise to be soundproofed. Therefore, in order to realize sufficient soundproofing, it is necessary to form many concave portions 51a having a small width depending on the wavelength of the noise. Therefore, the number of slits 51b formed between these concave portions 51a is also large. As a result, there arises a problem that the amount of concrete used tends to be excessive. Because of this, it is usually necessary to design and mold the embedding material while limiting the number of slits 51b to be formed so that the amount of concrete used is not excessive. The embedding material has a problem that the frequency range of the noise that can be sufficiently soundproofed is narrow. Furthermore, a narrow slit 5
The use of 1b may cause a problem that the concrete is insufficiently poured and it is difficult to cast and join the pipes completely in the vertical direction, thereby lowering the soundproofing performance.

Accordingly, the present invention advantageously solves the above-mentioned conventional problems, and provides a mold and a concrete slab for burying a hollow concrete slab which can sufficiently prevent noise in a wide frequency range with a small amount of concrete. To provide.

[0007]

In order to solve the above-mentioned problems, the invention according to claim 1 comprises a space portion formed by a top plate portion and a vertical plate portion, the lower surface of which is surrounded by being opened. In a mold for embedding a hollow concrete slab having a falling box shape, a lower portion of the top plate portion has a through hole for filling concrete penetrating from an upper surface of the top plate portion to a lower surface of the space portion. It is characterized in that a column-shaped tube is disposed while maintaining an interval from the vertical plate portion.

In general, the relationship between the floor and the impact sound is that the entire surface of the floor surrounded by beams and walls does not vibrate uniformly. It is known that the vibration is small from the periphery of the floor to a distance of λ of the wavelength λ of the bending wave, and the vibration increases when the distance is １ ／ or more. Therefore, assuming that an area at a distance of λ / 4 from the periphery of the floor is a vibration-ineffective area and an area at a distance of λ / 4 or more is a vibration area, the relationship between this vibration area and noise was investigated. It was confirmed that the noise increased in proportion to the radiation area.

The above-described configuration is based on such knowledge and focuses on the vibration-ineffective region (vibration region). The through-hole formed by the columnar tube is spaced from the vertical plate by maintaining the space. By arranging it in the section, concrete is filled and poured into the section, and as a result, a certain range of vibration-ineffective area can be formed around the filled concrete. That is,
In this configuration, a vibration-ineffective region in the space in the form is formed from both inside and outside by a tube having an outer vertical plate portion and an inner (center side) through-hole, so that a wide and efficient area can be ensured. It becomes possible. Therefore, while the amount of concrete used to fill the through hole of the pipe is sufficiently small as a whole, the vibration area is significantly reduced by effectively expanding the vibration ineffective area, and the noise radiation area is reduced. This makes it possible to sufficiently prevent noise in a wider frequency range. Furthermore, according to this configuration, since a tube having a through hole having a large diameter is used as compared with the conventional one using a narrow slit, the concrete can be easily and reliably filled and poured, and the concrete can be densely arranged vertically. As a result,
There is no fear that the soundproofing characteristics are partially degraded.

According to a second aspect of the present invention, there is provided a mold for embedding a hollow concrete slab according to the first aspect, wherein the outer shape of the hollow concrete slab having a falling box shape is rectangular in a plan view. It is characterized by: According to the above configuration, the best mold can be obtained when the through holes are arranged in a substantially equilateral triangle.

According to a third aspect of the present invention, there is provided a mold for embedding a hollow concrete slab according to the first or second aspect, wherein the space portion is one and the column-shaped tubular body is provided in plurality. Features. According to the above configuration, by providing a plurality of pipes for one space portion,
Since the through-holes of the tube can be distributed over a wide area of the space, the vibration-ineffective area can be further expanded.

According to a fourth aspect of the present invention, there is provided a mold for embedding a hollow concrete slab according to the second or third aspect, wherein the plurality of pipes are symmetrical with respect to a longitudinal center line of the mold. And are arranged so as to form vertices of a substantially equilateral triangle when connecting the center points of the through holes. According to the above configuration, it is possible to easily obtain the minimum necessary arrangement of the through holes that exhibit sufficient soundproof performance.

According to a fifth aspect of the present invention, there is provided a mold for embedding a hollow concrete slab according to any one of the first to fourth aspects, wherein the tubular body is located on a center line in a longitudinal direction of the mold. And a notch in a vertical plate portion opposed to a line segment perpendicular to the center line. According to the above configuration, it is possible to more sufficiently reduce the noise radiation area due to the vibration region.

According to a sixth aspect of the present invention, a concrete slab is provided with the hollow concrete slab embedding form according to any one of the first to fifth aspects. According to the above configuration, it is possible to obtain a concrete slab that is lightweight and sufficiently exhibits soundproofing performance.

[0015]

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIGS. 1 and 2, the formwork for embedding the hollow concrete slab according to the present embodiment has a rectangular top plate 1a and a top plate 1a.
And a vertical plate portion 1b hanging down from the four sides, and the plate portions 1a and 1b form a rectangular box-shaped falling box shape.
The mold 1 has a space portion 5 formed by being surrounded by a top plate portion 1a and a vertical plate portion 1b with a lower surface opened (opened). In addition, the mold 1 may be formed in a cubic shape, a triangular prism shape, a polygonal prism shape, or a cylindrical shape in addition to the rectangular parallelepiped shape. When the through holes 2 are arranged in a substantially equilateral triangle as will be described later, it is preferable that the outer shape of the mold 1 be a rectangular shape in plan view (the top plate portion 1a has a rectangular shape such as a rectangle or a quadrangle). .

The mold 1 is made of a foamed molded article made of a synthetic resin such as polyethylene or polystyrene. still,
The mold 1 may be made of polyethylene, polypropylene, polyvinyl chloride, a copolymer mainly composed of these, in addition to the above-mentioned polyethylene foam or polystyrene foam. Further, the same frame 1 may be formed of paper such as cardboard or cardboard, or a water-soluble resin such as polyvinyl alcohol or polyvinylpyrrolidone. In this case, since the mold 1 can be embedded in the hollow concrete slab and then decomposed with moisture, it is possible to save the time and effort for separating and collecting the mold 1 when demolishing a building, for example. Furthermore, the mold 1 may be formed of a biodegradable resin represented by polylactic acid, polycaprolactone, starch-based resin, and the like. In this case, for example, even if the building is left after being demolished, Since it is decomposed by microorganisms in the soil, deterioration of the natural environment can be reliably prevented. further,
The formwork 1 may be formed of metal such as aluminum, ceramics, or carbon fiber. In this case, extremely high rigidity can be given to the hollow concrete slab.

Further, a plurality of through holes 2 for filling concrete formed in a square shape in plan are formed in the top plate portion 1a of the formwork 1. Each through-hole 2 is formed in a column-shaped tube 12 provided with a space from the vertical plate portion 1b. The tube 12 is formed from the top plate 1 a to the lower surface of the space 5. The through hole 2 in the tube 12 communicates the upper surface of the top plate 1 a with the lower surface of the space 5. I have. As shown in FIG. 3, these through holes 2 are arranged symmetrically with respect to the center line A in the longitudinal direction of the mold 1, and when the center points of the through holes 2 are connected, substantially They are arranged to form the vertices of an equilateral triangle. The through-holes 2 arranged in such a positional relationship give the mold 1 a unique function of sufficiently suppressing the resonance phenomenon in the space portion 5 with a small amount of concrete used.

A method and operation of applying the form 1 to the hollow concrete slab in the above configuration will be described.

First, as shown in FIG.
After assembling the lower slab reinforcement 9 and the truss reinforcement 10 on the steel mounting table, concrete is cast and the concrete substrate 6 is formed. And concrete board 6
Is uncured, the mold 1 is placed at a predetermined position, and the mold 1 is fixed to the concrete substrate 6 using a not-shown locking tool. Thereafter, the concrete substrate 6 is left to cure until the mold 1 and the reinforcing bars 9 and 10 are fixed to the concrete substrate 6.
When they are firmly integrated, they are removed from the steel mounting table and transported to a site such as an apartment house.

At the site, as shown in FIG. 6, after the concrete substrate 6 with the formwork 1 is set evenly at a predetermined position, the upper slab reinforcement 8 is arranged and the cast-in-place concrete 7 is poured. . The concrete 7 to be cast is shown in FIG.
As shown in (1), the space between the molds 1 and 3 is filled and the through hole 2 in the mold 1 is filled. Then, the cast-in-place concrete 7 is hardened and firmly joined to the concrete substrate 6 to form the hollow concrete slab 11 in which the hollow portion is formed by the space portion 5 of the formwork 1.

Next, when a person or an object moves on the hollow concrete slab 11 prepared as described above, the entire slab 11 and a portion corresponding to the hollow portion (space portion 5) in the slab 11 are vibrated. The force acts on. On this occasion,
Since the entire slab 11 has a large slab thickness and is formed by rigidly joining concrete to the reinforcing bars 9 and 10 connected three-dimensionally, vibrations that generate a large impact sound are not generated. Almost no.

On the other hand, the portion corresponding to the hollow portion (space portion 5) has a small slab thickness H1 · H2 obtained by subtracting the thickness of the formwork 1 from the total thickness H0 of the slab 11, and also suppresses bending waves. No arrangements have been made. Therefore, this portion is liable to generate an impact sound due to a resonance phenomenon. However, due to the arrangement of the through holes 2 of the formwork 1 and the concrete 7 filled in the through holes 2, the vibration is reduced to a predetermined frequency or less. On the other hand, it is possible to sufficiently prevent the generation of an impact sound.

That is, in general, the relationship between the floor and the impact sound is that the whole surface of the floor surrounded by beams and walls does not vibrate uniformly,
As shown in FIG. 7, the vibration ineffective length λ / 4
It is known to vibrate in the vibration region 22 excluding the vibration invalid region 23 up to (1/4 of the wavelength λ of the bending wave) (Sound insulation design material for building: 1988, Published by: Gihodo Publishing Co., Ltd.) Editor: Architectural Institute of Japan).

Here, in the mold 1 of the present embodiment, as shown in FIG. 3, the through holes 2 of the tube 12 are arranged symmetrically with respect to the center line A in the longitudinal direction of the mold 1. At the same time, the through holes 2 are arranged so as to form the vertices of a substantially equilateral triangle when the center points of the through holes 2 are connected. Therefore, the through-holes 2 are substantially evenly arranged with respect to the top plate 1 a (the portion corresponding to the floor 21) of the mold 1. And
As shown in FIG. 18, when the vibration-ineffective area 23 is formed around both the vertical plate portion 1 b and the through hole 2 of the form 1 by the concrete 7, the vibration-ineffective area 23 is formed.
Occupies most of the whole area, and the overlap between the areas becomes extremely small. As a result, the vibration region 22 (noise radiating area) decreases in proportion to the expansion of the vibration invalid region 23, so that the impact sound caused by the vibration of the vibration region 22 becomes extremely small.

As shown in FIG. 4, the mold 1 in the present embodiment is aligned with the through-hole 2 (tube 12) located on the longitudinal center line A of the mold 1 in the center line A. A configuration may be employed in which the notch 3 is formed in the vertical plate portion 1b opposed to the orthogonal line segment. According to this configuration, since the wall surface of the vertical plate portion 1b located around the top plate portion 1a and the through hole 2 approach the notch portion 3, the vibration region 22 can be completely eliminated, so that the impact sound can be eliminated. Can be made even smaller.

Further, the mold 1 in this embodiment is similar to the mold 1 shown in FIG.
As shown in the figure, the through-holes 2 are arranged symmetrically with respect to the center line A in the longitudinal direction of the mold 1 and, when the center points of the through-holes 2 are connected, the vertices of the substantially equilateral triangle are formed. Although the through-holes 2 are arranged to be formed, the present invention is not limited to this. That is, the mold 1 may be configured so as to reduce the vibration region 22 of the hollow concrete slab 11 due to the space 5 by the through hole 2 penetrating from the upper surface to the lower surface in the space 5. Specifically, the top plate 1a
A column-shaped pipe body 12 having a through hole 2 for filling concrete formed therethrough from the upper surface of the top plate portion 1a to the lower surface of the space portion 5 is provided below the vertical plate portion 1b while maintaining an interval from the vertical plate portion 1b. What is necessary is just to be made the configuration. Therefore, the mold 1
The following configuration is also possible.

That is, as shown in FIGS. 8 and 9, the mold 1 has a configuration in which the through holes 2 formed by the pipes 12 are arranged adjacent to one end while alternately straddling the center line in the longitudinal direction. Alternatively, as shown in FIG. 10 and FIG. 11, a configuration in which one first through hole 13 formed by connecting the through hole 2 to the center line in the longitudinal direction may be arranged.

Further, in the mold 1, as shown in FIGS. 12 and 13, the space portion 5 is divided in a longitudinal direction and a width direction by a partition wall 1c to form a plurality of small space portions 5a in a matrix. The configuration may be such that a circular through-hole 2 formed by a cylindrical tube body 12 is arranged in each small space portion 5a. Further, as shown in FIGS. 14 and 15, the formwork 1 forms a cylindrical small space portion 5a by a partition wall 1c, and a circular through hole 2 formed by a cylindrical tube body 12 in each small space portion 5a. May be arranged. In this case, generation of a vibration region can be reliably and easily prevented. Further, as shown in FIGS. 16 and 17, the mold 1 has a cylindrical outer shape with a circular top plate 1 a and an annular vertical plate 1 b hanging down from the outer peripheral end of the top plate 1 a. Alternatively, a configuration may be adopted in which a plurality of through holes 2 are arranged substantially evenly in the top plate 1a. In this case, it can be suitably used for a concrete structure having a curved outer wall.

Next, the soundproofing effect of the mold 1 of this embodiment was investigated. In the investigation, in addition to the mold 1 of FIG. 1 (type 1), two types of molds 1 (types 2 to 3) shown in FIGS. 8 to 11 as modified examples, and the mold 1 of FIG. Type). In addition, these molds 1 have a width of 450 m in order to unify the inspection conditions.
m, the length was set to 1200 mm, and the height was set to 260 mm. The top plate 1a, the vertical plate 1b, and the tube 12 were set to have a thickness of 20 mm, 20 mm, and 20 mm, respectively.

Then, for each type of mold 1 produced under such conditions, the amount of vibration reduction (dB) when impulsive sound to be soundproofed was applied was evaluated. FIGS. 18 to 20 and FIGS.
As shown in FIG. 5, a plan view of the mold 1 was prepared, and the area of the opening formed by all the through holes 2 was determined. Further, by obtaining a vibration invalid area 23 (hatched portion) based on the vibration invalid length λ / 4 of the impact sound from the periphery of the mold 1 and the periphery of the through hole 2.
Vibration area 22 deviating from vibration invalid area 23 (blank area)
Was determined. Table 1 shows the results.

[0032]

[Table 1]

As a result, the noise radiation area is 0.0285
according to increases and m ² ~0.0525m ² (type 1-3), the vibration reduction amount because the result is obtained that decreases with 10DB～7dB, and the noise emission area and vibration reduction amount is inversely proportional to It was confirmed that. Therefore, it has been clarified that an extremely large amount of vibration reduction can be obtained by designing to eliminate the noise radiation area.

In addition, the structure in which the through holes 2 are evenly arranged like the type 1 can minimize the amount of the concrete 7 by setting the opening area to 0.07 m ² , and provide excellent soundproofing performance due to a large amount of vibration reduction. It turned out to exert.

Further, in addition to the types 1 to 3, the mold 1 is shown in FIG.
2 to 17, the top plate 1
a through hole 2 for concrete filling, which is formed in a lower part of the space part 5 from the upper surface of the top plate part 1a to the lower surface of the space part 5.
It is confirmed that if the columnar tube body 12 having the structure described above is arranged with the space provided between the vertical tube portion 1b and the vertical plate portion 1b, a large vibration ineffective area 23 can be secured, so that the soundproof performance is surely exhibited. Was done.

Next, a method of designing the mold 1 will be described. In the following description, since it has been recognized that a design that eliminates the noise radiation area is desirable based on the above-described investigation results, a design method that focuses on eliminating overlap of the vibration-ineffective region 23 will be described. However, if design conditions such as upper and lower limit values are set for the area of the through-hole 2, the design is made to minimize the overlap of the vibration invalid area 23 while taking this design condition into consideration. I do.

First, the maximum frequency of the impact sound to be soundproofed is determined, and the vibration ineffective length λ / 4 corresponding to this maximum frequency is determined.
Ask for.

Specifically, as shown in FIG. 5, when the slab thicknesses corresponding to the upper side and the lower side of the mold 1 in the hollow concrete slab 11 are an upper slab thickness H1 and a lower slab thickness H2, respectively, The wavelength λ of the bending wave with respect to the frequency f is calculated by the following equation.

Λ = √ (π ^* CL ^* min [H1, H2] / √3 / f) (1)

However, CL is the hollow concrete slab 11
It is a longitudinal wave. In general, the total thickness H0 of the hollow concrete slab 11 is 200 mm to 300 mm,
Has a width of 400 to 500 mm and a length of the mold 1 of 500 to 1
The upper slab thickness H1 and the lower slab thickness H2 of the hollow concrete slab 11 are set to 60 to 100 mm.

Thus, the hollow concrete slab 11
Slab thickness H1 / H2 (60mm, 80mm, 100m
m) is 500Hz, 1kHz, 2kHz
Assuming that z is 4 kHz, the wavelength of the bending wave can be calculated as shown in Table 2 from the above formula (1).

[0042]

[Table 2]

As a result, for example, when the design specification is determined that the slab thickness H1 · H2 of the hollow concrete slab 11 is 60 mm and the maximum frequency of the impact sound to be soundproofed is 4 kHz, the wavelength corresponding to the design specification is determined. λ is shown in Table 2.
To 302 mm. Then, the vibration ineffective length λ / 4 is obtained based on the wavelength λ.

Next, for example, as shown in FIG.
The shape and size of the top plate 1a in the mold 1 are determined. Then, the first vibration ineffective area 23a is obtained at a distance of the vibration ineffective length λ / 4 from the periphery of the top plate 1a. After this, FIG.
As shown in FIG. 1B, at both ends in the longitudinal direction of the first vibration-ineffective area 23a, the vibration-ineffective area corresponding to the vibration-ineffective area formed by the inward direction from the boundary of the first vibration-ineffective area 23a. Through hole 2 at a distance of length λ / 4
And determine the dimensions of the through hole 2. Then, the second vibration ineffective area 23b formed by the through hole 2 is set to a vibration ineffective length λ /
Determined based on 4.

Thereafter, as shown in FIG.
The through-hole 2 is disposed at a distance of the vibration-ineffective length λ / 4 from the boundary between the vibration-ineffective region 23a and the second vibration-ineffective region 23b, and the third vibration-ineffective region 23c formed by the through-hole 2 is moved to the vibration-ineffective length λ / Determined based on 4. The third vibration invalid area 23c may be separated from the third vibration invalid area 23c.
Are overlapped, the dimensions of the through-holes 2 are changed, or the number of the through-holes 2 is increased or decreased, so that the boundaries of the third vibration-ineffective areas 23c coincide with each other, and the arrangement of the through-holes 2 is changed. decide.

[0046]

According to the first aspect of the present invention, there is provided a hollow concrete slab for laying a hollow box-shaped slab having a space formed by being surrounded by a top plate and a vertical plate with the lower surface thereof open. In the formwork, a column-shaped pipe having a through hole for concrete filling formed so as to penetrate from the upper surface of the top plate portion to the lower surface of the space portion at a lower portion of the top plate portion to be spaced from the vertical plate portion. It is a configuration that is held and arranged.

According to the above configuration, by disposing the through-hole formed by the column-shaped tube while maintaining the gap with the vertical plate portion,
As a result of filling and pouring the concrete, a certain range of vibration-ineffective area can be formed around the filled concrete. That is, in the present configuration, a vibration-ineffective region in the space in the mold is formed from both inside and outside by a tube having an outer vertical plate portion and an inner (central side) through-hole, thereby ensuring a wide and efficient area. It becomes possible. Therefore,
While the amount of concrete used to fill the through-holes of the pipe is sufficiently small as a whole, the vibration area is greatly reduced by the effective expansion of the vibration-ineffective area, and thus the noise emission area is widened. It is possible to sufficiently prevent noise in the frequency range. Furthermore, according to this configuration, since a tube having a through hole with a large diameter is used as compared with a conventional one using a narrow slit,
The concrete is easily and reliably filled and poured, and as a result of being closely joined up and down, there is an effect that there is no fear that the soundproofing characteristics are partially deteriorated.

According to a second aspect of the present invention, there is provided the mold for embedding a hollow concrete slab according to the first aspect, wherein the outer shape of the hollow concrete slab having a falling box shape is rectangular in a plan view. Configuration. According to the above configuration, the best mold can be obtained when the through holes are arranged in a substantially equilateral triangle.

According to a third aspect of the present invention, there is provided a mold for embedding a hollow concrete slab according to the first or second aspect, wherein the space portion is one and the column-shaped tube is provided in plurality. is there. According to the above configuration, by providing a plurality of pipes for one space, the through holes of the pipes can be dispersedly arranged in a wide range of the space, so that the vibration ineffective area is further expanded. It has the effect that it can be done.

According to a fourth aspect of the present invention, there is provided a mold for embedding a hollow concrete slab according to the second or third aspect, wherein the plurality of pipes are symmetrical with respect to a longitudinal center line of the mold. The arrangement is such that, when the center points of the through holes are connected to each other, a vertex of a substantially equilateral triangle is formed. According to the above configuration, there is an effect that it is possible to easily obtain the minimum necessary arrangement of the through holes that exhibit sufficient soundproof performance.

According to a fifth aspect of the present invention, there is provided a mold for embedding a hollow concrete slab according to any one of the first to fourth aspects, wherein the tubular body is located on a longitudinal center line of the mold. And a notch in a vertical plate portion opposed to a line segment orthogonal to the center line. According to the above configuration, there is an effect that the noise emission area due to the vibration region can be more sufficiently reduced.

According to a sixth aspect of the present invention, a concrete slab is provided with the hollow concrete slab embedding form according to any one of the first to fifth aspects. According to the above configuration, there is an effect that a concrete slab which is lightweight and sufficiently exhibits soundproofing performance can be obtained.

[0053]

[Brief description of the drawings]

FIG. 1 is a perspective view showing a part of a mold frame in a cutaway manner.

FIG. 2 is a perspective view of a mold.

FIG. 3 is an explanatory diagram showing an arrangement of through holes.

FIG. 4 is an explanatory diagram showing a positional relationship between a notch and a through hole.

FIG. 5 is a longitudinal sectional view of a hollow concrete slab.

FIG. 6 is an explanatory diagram showing a state where a formwork is arranged in an apartment house or the like.

FIG. 7 is an explanatory diagram showing a relationship between a vibration region and a vibration invalid region.

FIG. 8 is a perspective view showing a part of the mold frame in a cutaway manner.

FIG. 9 is a perspective view of a mold.

FIG. 10 is a perspective view showing a part of a mold frame in a cutaway manner.

FIG. 11 is a perspective view of a mold.

FIG. 12 is a perspective view showing a part of the mold in a partially broken manner.

FIG. 13 is a perspective view of a mold.

FIG. 14 is a perspective view showing a part of the mold frame in a cutaway manner.

FIG. 15 is a perspective view of a mold.

FIG. 16 is a perspective view showing a part of the mold frame in a cutaway manner.

FIG. 17 is a perspective view of a mold.

FIG. 18 is an explanatory diagram showing a state of a vibration invalid area and a vibration area.

FIG. 19 is an explanatory diagram showing states of a vibration invalid area and a vibration area.

FIG. 20 is an explanatory diagram showing states of a vibration invalid region and a vibration region.

FIG. 21 is an explanatory view showing a design process of a formwork;
Shows a process of determining a first vibration-ineffective region, (b) shows a process of determining a second vibration-ineffective region, and (c) shows a process of determining a third vibration-ineffective region.

FIG. 22 shows a conventional example, and is an explanatory view showing an arrangement state of a slit formed in a mold and a concave portion.

FIG. 23 shows a conventional example, and is an explanatory view showing an arrangement state of a slit formed in a mold and a concave portion.

FIG. 24 is an explanatory diagram showing a state of a vibration invalid region and a vibration region of the mold in FIG. 22;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Formwork 1a Top plate part 1b Vertical plate part 1c Partition wall 2 Through-hole 3 Notch 5 Space part 7 Concrete 11 Hollow concrete slab 12 Tube 13 First through-hole 14 Second through-hole 21 Floor 22 Vibration area 23 Vibration invalid region

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hideo Utsuno 1-5-5 Takatsukadai, Nishi-ku, Kobe-shi, Hyogo Kobe Steel, Ltd. Kobe Research Institute (56) References JP-A-11-71847 ( JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E04B 5/32 E04B 5/43

Claims (6)

(57) [Claims] 1. A mold for burying a hollow concrete slab having a hollow box-like shape provided with a space formed by surrounding a top plate portion and a vertical plate portion with its lower surface opened. A column-shaped pipe having a through hole for concrete filling formed by penetrating from the upper surface of the top plate portion to the lower surface of the space portion is provided at a lower portion of the portion while maintaining an interval with the vertical plate portion. Formwork for burying hollow concrete slabs, characterized by the following. 2. The mold for embedding a hollow concrete slab according to claim 1, wherein the outer shape of the mold for embedding a hollow concrete slab having the shape of a falling box is rectangular in a plan view. 3. The formwork for burying a hollow concrete slab according to claim 1, wherein the space portion is one and the column-shaped tube body is provided in plurality. 4. The plurality of pipes are disposed symmetrically with respect to a center line in a longitudinal direction of the mold, and have a vertex of a substantially equilateral triangle when connecting the center points of the through holes. The mold for burying a hollow concrete slab according to claim 2, wherein the form is arranged so as to form the following. 5. A notch portion is provided in a vertical plate portion opposed to a pipe located on a center line in a longitudinal direction of a formwork on a line segment orthogonal to the center line. The mold for burying a hollow concrete slab according to any one of claims 1 to 4. 6. A concrete slab, comprising the formwork for burying a hollow concrete slab according to any one of claims 1 to 5.