JP3004864B2 - Embedding material for concrete slab and substrate for hollow concrete slab using the embedding material - Google Patents

Abstract

PURPOSE:To obtain an embedded material for a concrete slab, preventing intrusion of water to hollow parts when water is sprinkled at the time of construction on site. CONSTITUTION:In an embedded material 50 for a concrete slab, of a foam molded piece made of a synthetic resin and provided with hollow parts 4 opened at the lower surface thereof, through holes 30 are each inclinedly formed in a side wall part 5a so that an end part 31 positioned on the side of the hollow part 4 is higher than an end part 32 positioned outside. In this manner, inclination of the through holes 30 prevents sprinkled water from intruding to the hollow parts 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an embedding material for a concrete slab formed of a synthetic resin foam molded article and a substrate for a hollow concrete slab using the embedding material.
An improved concrete slab that can effectively drain the water that has accumulated in the internal space surrounded by the embedded material and the concrete substrate during the production of substrates for hollow concrete slabs and the construction of finished products on site. The present invention relates to an embedding material and a base material for a hollow concrete slab using the embedding material.

[0002]

2. Description of the Related Art As a construction method of a concrete slab constructed as a floor material or a ceiling material of a building, a hollow material or a lightweight embedding material is embedded in concrete for the purpose of reducing the weight and improving a sound insulation effect. It is generally widely used to use it. However, such a construction method has the drawbacks that it takes a lot of time to manufacture the hollow portion, and it is not easy to attach the embedding material.

As a technique for solving these problems, as disclosed in Japanese Patent Publication No. 57-47008, an embedding material made of a synthetic resin foam molded article is provided during a curing process in which a concrete substrate is uncured. It is also known that the embedding material is fixed to the concrete substrate using a locking tool, and the embedding material is connected and fixed to the concrete substrate by solidifying the concrete substrate. FIG. 7 schematically shows the structure of such a conventional substrate for a hollow concrete slab.

In FIG. 7, in order to assemble a substrate A for hollow concrete slab, first, a grid-like reinforcing bar 2 on which a truss bar 1 is fixed is set on a mounting table (not shown), and is surrounded by the reinforcing bar 2. The concrete substrate 3 is molded by placing the kneaded concrete in the frame. Next, while the concrete substrate 3 is uncured, a box-shaped embedding material 5 having a hollow portion 4 with an open lower surface made of a synthetic resin foam molded product is arranged at a predetermined position, and the locking tool 6 is moved. The embedding material 5 is fixed to the concrete substrate 3 by using the same. Thus, a hollow portion 4 surrounded by the embedding material 5 and the concrete substrate 3 is formed. Then, the concrete hardens through the steam curing process, and the embedding material 5 is firmly integrated with the concrete substrate 3. After the hollow concrete slab substrate A manufactured in this way is carried into the site and set at a predetermined position,
Reinforcement work or plumbing work is performed as necessary, and then post-placed concrete 7 is cast on site to complete the concrete slab work.

As another method of assembling the substrate for hollow concrete slab, after the concrete substrate 3 has been sufficiently cured through a steam curing process, an adhesive (not shown) is applied to the surface of the concrete substrate without using the above-mentioned locking member. It is also known that the embedding material 5 is adhered and attached integrally via the same (see JP-A-5-208411). The substrate for hollow concrete slabs having such a structure and a manufacturing method is capable of reducing the weight of the concrete slab because the embedding material is not lifted at the time of post-casting concrete and the hollow portion is reliably formed at a predetermined position. An improvement in sound insulation can be achieved.

However, in the above-mentioned conventional substrate for hollow concrete slab, for example, during the steam curing step at the time of manufacturing the substrate for hollow concrete slab, steam is trapped in the hollow portion surrounded by the embedding material and the concrete substrate, The embedded material was sometimes deformed by the steam heat in the hollow portion. Further, even after the completion of the steam curing step, the steam remains as water droplets, delaying the drying of the concrete at the portion where the embedding material is installed. Furthermore, when performing rebar work or piping work at the site, the exposed embedded material may be overly trampled or steel material may be dropped.The embedded material is a synthetic resin foam molded product. For this reason, fine cracks may be generated in the embedding material. In addition, moisture infiltrates at the time of watering work performed at the time of on-site construction, and rainwater also infiltrates from such cracks.

The applicant of the present invention has proposed an improved hollow concrete slab substrate for solving the above-mentioned inconveniences which may occur in a hollow concrete slab substrate, as shown in FIG. A substrate for a hollow concrete slab using an embedding material 5 in which an opening 7 for connecting the hollow portion 4 to the outside is formed in a bottom surface 5b where a bottom 5a is in contact with a concrete substrate has been proposed (Japanese Patent Laid-Open Publication No. Hei. 2
08410). In the substrate for a hollow concrete slab having this configuration, steam or moisture that has entered the hollow portion surrounded by the embedding material and the concrete substrate from cracks or the like during steam curing in the manufacturing process or during slab construction, Since the water is discharged to the outside through the opening 7 during curing or on-site construction, the above-mentioned inconvenience associated with the inclusion of moisture has been improved.

[0008]

SUMMARY OF THE INVENTION The present inventor has conducted a construction experiment using a hollow concrete slab substrate having an opening for communicating the above hollow portion with the outside.
I learned that there is something to improve. That is,
After arranging the hollow concrete slab substrate at a predetermined position at the construction site, watering work is performed on the surface of the hollow concrete slab substrate in order to make the concrete substrate and post-cast concrete to be newly cast compatible. Since the opening 7 is basically formed as a concave groove on the side surface 5b where the side wall surface of the embedding material comes into contact with the concrete substrate as shown in FIG. There is a case where the water enters the hollow portion 4. Usually, after-watering is performed in a very short time after the water is sprinkled, so that the post-injected concrete is cast before the infiltrated water cannot escape to the outside again. In some cases, the construction of the concrete slab was terminated while keeping the water inside.

An object of the present invention is to solve the above-mentioned inconveniences at the time of construction. More specifically, the present invention is capable of removing necessary steam or water from the hollow portion during steam curing. To provide an embedding material for concrete slab and a substrate for hollow concrete slab using the embedding material, which can alleviate infiltration of water into the hollow portion at the time of watering performed during casting of post-cast concrete. It is in.

[0010]

In order to solve the above-mentioned problems and to achieve the object, an embedding material for a concrete slab according to the present invention is made of a synthetic resin foam molded article and has a hollow portion opened on the lower surface. And, a through hole is formed in the side wall portion to communicate the hollow portion to the outside, and the through hole has an end located at the hollow portion side more than an end portion located at the external side. It is characterized by being formed in an inclined state so as to be at a high position.

In a preferred embodiment, the through-hole is tapered from an end located on the hollow side to an end located on the outer side, and the hollow is formed by a wall. It is also a preferable embodiment that a plurality of sections are formed, and in this case, a cutout is partially formed in a bottom surface of the wall section that defines the hollow section. The present invention also discloses a substrate for a hollow concrete slab having an embedding material having the above-mentioned shape on a concrete substrate.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embedding material according to the present invention and a substrate for a hollow concrete slab using the same. FIG. 1 is a perspective view showing one embodiment of a concrete slab embedding material 50 according to the present invention, and FIG. 2 is a sectional view of a concrete slab using the embedding material 50 shown in FIG. In this embodiment, the embedding material 50 is formed from a synthetic resin foam material such as expanded polystyrene similarly to the conventional example described with reference to FIGS. It has a box-like shape having a large number of open hollow portions 4.
A lattice-shaped wall 5d is provided in the hollow portion 4 to provide strength. A cutout 10 is formed in the side wall portion 5a of the embedding material 50 for recessing a locking tool 6 used for fixing the embedding material 50 to the concrete base material 3.

A through hole for communicating the hollow portion 4 formed inside the embedding material 50 to the outside is provided below the side wall portion 5a of the embedding material 50 (near the position where the embedding material 50 contacts the concrete substrate 3). 30 are provided. As shown in FIG. 2, the through hole 30 is formed so as to be inclined such that the opening end 31 located on the hollow portion 4 side is higher than the opening end 32 located on the outside. I have. The opening end 32 located on the outer side is formed at the same level as or slightly above the surface of the concrete substrate 3 when the embedding material 50 is fixed to the concrete substrate 3.

The cross-sectional shape of the through hole 30 is optional.
The cross section may be a circular cross section, an elliptical cross section, or the like, or may be a flat rectangular cross section as shown in FIG. 1 showing only the opening end 32 located on the outer side thereof. The cross-sectional shape may be the same between both ends, or may be different. Although not particularly shown, the cross-sectional area of the through hole 30 is such that the opening end 32 side located on the outer side is narrower than the opening end 31 side located on the hollow part 4 side, and the tapered shape as a whole is The shape is a preferable shape, and as described later, the water inflow during curing watering can be further reduced.

Although the number of the through holes 30 is not particularly limited,
It is preferable to form one for each hollow portion. Next, a process of manufacturing a substrate for hollow concrete slab using the embedding material 50 and a state of constructing a concrete slab using the substrate for hollow concrete slab will be described. When manufacturing substrates for hollow concrete slabs,
The embedding material 50 is disposed on the concrete substrate 3 in the same manner as described above with reference to FIG. Steam curing is performed in that state, and in the process, steam infiltrates into the hollow portion 4 surrounded by the embedding material 50 and the concrete substrate 3. However, since this steam is discharged to the outside through the through-hole 30, inconveniences such as deformation of the embedding material accompanying the enclosing of the high-pressure steam are avoided.

The concrete is hardened and the embedding material 50 is firmly integrated with the concrete substrate 3 to complete the hollow concrete slab substrate. After the formed hollow concrete slab substrate is carried into the site and set at a predetermined position, after reinforcing or piping work as necessary, to improve the adhesion between the concrete slab substrate and the post-cast concrete, Further, water is sprayed on the concrete substrate 3 in order to prevent insufficient strength of the post-cast concrete due to water absorption of the concrete substrate 3 and to prevent cracks due to drying shrinkage.

Since pressurized water is usually used for this sprinkling, an embedding material having a shape as shown in FIG. 8, that is, an opening 7 is formed by the side wall surface 5a of the embedding material 5 and the surface 5b in contact with the concrete substrate 3 In the case where the embedding material is simply formed as a groove, sprinkled water may penetrate into the hollow portion 4 of the embedding material through the opening 7. In this case, since the through-hole 30 is formed in an inclined shape with the end on the hollow portion 4 side being at a high position, it is possible to avoid water sprinkled into the hollow portion 4.

As described above, when a worker excessively steps on or drops a steel material at the time of arranging or piping, a fine crack is generated in the embedding material, and the crack enters the hollow portion 4 from the crack. Moisture infiltrates during the watering work, and if there is rainfall, rainwater infiltrates. However, this infiltration water is
Since the water can easily flow out through the outer portion 0, a large amount of water is not stored in the hollow portion 4. When the embedding material of the present invention is used, moisture from the surface of the concrete substrate 3 to the height of the hollow portion side end 31 of the through hole 30 remains in the hollow portion 4 and is not discharged. However, it is possible to adjust the amount by adjusting the inclination of the through-hole 30 and since such a small amount of water does not affect the concrete slab, such residual water can be ignored. .

After the water is sprinkled, the post-cast concrete 7 is poured and the concrete slab is completed (see FIG. 2). However, in the embedding material according to the present invention, water is injected into the hollow portion 4 when water is sprinkled as described above. Even if a large amount of water does not enter, even if a large amount of water enters through a crack or the like, almost all of the water flows out from the through hole 30 and only a very small amount of water remains. It is possible to avoid placing the post-cast concrete while holding a large amount of water. When the through-hole 30 is tapered to the outside, the water in the hollow portion 4 is easily discharged, and conversely, the water from the outside is difficult to enter, so that the initial purpose is more completely achieved. .

The above description is only one embodiment of the concrete slab embedding material and the hollow concrete slab substrate using the embedding material according to the present invention, and there are many other modifications. In the above description, the hollow portion is divided into a number of sections by the wall 5d, and one hollow hole 4 is provided for each of the divided hollow sections 4, but FIG.
As shown in FIG. 5, a notch 5e is provided in a part of the wall 5d to provide a gap between the lower end of the wall 5d and the surface of the concrete substrate 3, so that the plurality of hollows can communicate with each other. Therefore, the initial purpose can be achieved only by forming one through hole in the plurality of hollow portions, and the overall configuration can be simplified.

In manufacturing a substrate for a hollow concrete slab, it is not always essential to dispose the embedding material in a state where the concrete substrate is not cured, as already disclosed in JP-A-5-208411. Alternatively, after the concrete substrate is sufficiently hardened, an embedding material may be attached to the surface of the concrete substrate via an adhesive without using the above-described locking tool, and may be integrally attached. In that case, the locking tool 6 and the notch 10 for the locking tool as shown in FIG. 1 are unnecessary, and the external shape of the embedding material 50a can be made simpler as shown in FIGS. And the production of the embedding material is facilitated.

Further, the cross-sectional shape of the embedding material is not limited to a square as shown in FIGS. 1 and 2, for example, a shape in which the upper surface 5c is inclined like a roof as shown in FIG. In such a case, the water in the concrete to be stamped on the embedding material flows as indicated by arrow a, so that drainage becomes good, and An additional effect is provided in that damage due to freezing, which tends to occur during construction on the ground, is prevented.

[0023]

As is apparent from the above description, according to the present invention, it is possible to reliably discharge steam and moisture entering the hollow portion surrounded by the embedded material and the concrete substrate to the outside. Since it is possible to effectively prevent moisture from penetrating into the hollow portion at the time of watering performed during casting of post-cast concrete, deformation of the substrate for the hollow concrete slab after the steam curing process and after construction of the finished product at the site. Cracking can be more reliably prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of an embedding material for a concrete slab according to the present invention.

FIG. 2 is a schematic sectional view of a hollow concrete slab using an embedding material according to the present invention.

FIG. 3 is a sectional view showing a base material for a hollow concrete slab using an embedding material of another embodiment.

FIG. 4 is a perspective view showing an embedding material according to still another embodiment as viewed from above.

5 is a perspective view of the embedding material shown in FIG. 4 as viewed from below.

FIG. 6 is a schematic sectional view of a hollow concrete slab using an embedding material of still another embodiment.

FIG. 7 is a sectional view schematically showing a conventional hollow concrete slab.

FIG. 8 is a perspective view of a conventional embedding material viewed from below.

[Explanation of symbols]

3: concrete board, 50: embedding material, 5a: side wall,
5c: upper surface, 5d: wall, 4: hollow, 30: through hole, 31: hollow end, 32: external end

Claims (5)

(57) [Claims] 1. An embedding material for a concrete slab which is made of a synthetic resin foam molded article and has a hollow portion opened on the lower surface, wherein an end located on the hollow portion side on the side wall portion is located on the outer side. An embedding material for a concrete slab, wherein a through hole which is inclined so as to be located at a position higher than an end to be formed is formed. 2. The filling according to claim 1, wherein the through-hole has a tapered shape from an end located on the hollow side to an end located on the outer side. Material. 3. The embedding material according to claim 1, wherein said hollow portion is divided into a plurality of portions by a wall portion. 4. A method according to claim 1, wherein:
4. A partly cutout is formed.
The embedding material described. 5. A substrate for a hollow concrete slab having the embedding material according to claim 1 on a concrete substrate.