JPH09279742A - Work execution method for floor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work execution method which eliminates the need for the work of arranging reinforcement and installation and removal of formwork and shoring in constructing a thick concrete floor, and which can provide high strength. SOLUTION: A half-precast floor board 6 is formed in advance and prepared in which at least one set of truss reinforcements 5 has its lower part partly embedded, the set of truss reinforcements 5 comprising deformed reinforcements with uneven surfaces spaced apart and placed at the top and the bottom with beam deformed reinforcement 2 spirally wound around the top and bottom deformed reinforcements 1. After the half-precast floor boards 6 are aligned in a position where they constitute the floor of a building, the tops of the truss reinforcements 5 projecting from the half-precast floor boards 6 are provided with vertical 12 and horizontal 13 reinforcements if necessary, and concrete is cast over the half-precast floor boards 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a floor, and more particularly to a method for constructing a floor of a reinforced concrete building requiring a thick floor slab in a nuclear facility or a structure.

[0002]

2. Description of the Related Art In general, when constructing a concrete floor having a particularly high load such as a nuclear facility or an industrial facility, a floor structure having a thickness several times that of a normal floor is required. Explaining the construction process with reference to FIG. 5, the formwork 20 having reinforcing bars inside is used as the base 2
The concrete floor was formed by placing the concrete in the formwork 20 after supporting it by the supportwork 21 erected in 2 and removing the formwork 20 and the supportwork 21 after curing.

However, in the case of a high load floor, the thickness thereof may be about 50 cm, and in addition to the formwork 20 and the support 2 being extremely large-scale, the rebars assembled on site are complicated. Will be things. Moreover, cutting the rebar,
Bending and arranging everything on-site markedly reduced work efficiency and lengthened the construction period.

Therefore, there is a case where a method is used in which the reinforcing bars are mass-produced in advance as a structure having a certain amount and they are appropriately combined and used in the field. In other words, by welding the girder reinforcing bars formed in a zigzag shape between the two main bars arranged in parallel to form a truss bar in advance at a factory, etc., it is possible to save some labor on site. It is possible.

[0005]

However, in the conventional concrete floor construction method as described above, in order to secure the strength of the truss reinforcement, it is necessary to use all the rods which are surely welded. However, the round bar has a problem that the truss bars and the concrete are not integrated with each other, and cannot be applied to a structure having a high load. Under such circumstances, it was difficult to simplify the work of arranging.

Although it is possible to mass-produce precast floor slabs with a sufficient thickness from the beginning and sequentially place them on site, it is unavoidable that the weight is high, and not only is it expensive to transport, There were problems such as the need for a special crane to carry it into the structure, and it was thought that actual construction would be difficult.

Therefore, after all, there is only a method of assembling the above-mentioned formwork on site,
Therefore, the erection and removal of the formwork 20 and the supporting work 21 are indispensable works, and the construction period could not be shortened.

The object of the present invention is to solve the above-mentioned conventional problems. When constructing a concrete floor having a large thickness, the work of arranging and erection and removal of formwork and support work are performed. It is to provide a floor construction method that can obtain high strength in a short period of time.

[0009]

The present invention is a floor construction method, which is configured as follows to solve the above-mentioned technical problems. That is, the floor construction method of the present invention, the deformed reinforcing bars having uneven portions on the surface are arranged at intervals above and below, and the deformed reinforcing bars for girders are wound so as to spirally surround the upper and lower deformed reinforcing bars. Preforming and preparing a half precast floor slab in which the lower part of at least one set of trusses constructed is partially buried, and then at least one or more of said half precast floor slabs as a building floor It is characterized in that it is arranged at a position to be, and then, by pouring concrete on the half precast floor slab so as to bury the upper portion of the truss reinforcement protruding from the half precast floor slab. .

Here, the truss bar, which is an important component in the present invention, is composed of vertically arranged deformed bars and spirally wound bar deformed bars. It also includes a case where the deformed bar for girder is spirally wound around the deformed bar of which the triangular deformed bar or the rectangular bar is formed by setting the deformed bar of 1 to 2 and the deformed bar on the lower side to 2.

Since the deformed bar for girders are spirally wound around the deformed bars which are arranged at intervals, a predetermined strength is exhibited even if they are not adhered.
However, if the deformed bar and the deformed bar for girders are bonded or welded together with an adhesive or the like, a temporary load before being filled with concrete can be supported. The half precast floor slab is a concrete slab in which the lower portion of the truss bars described above is partially embedded in concrete and the upper portion is exposed from the surface, and can be manufactured in large quantities in advance in a factory or the like.

<Concrete Construction of the Present Invention> The floor construction method according to the present invention comprises the above-mentioned essential constituent elements, but the constituent elements are also concretely established in the following cases. The specific constituent elements are a plurality of the truss bars attached to one of the half precast floor slabs, and the half precast floor slabs are arranged at a position to be a floor of a building, and then, from the half precast floor slabs. The vertical and horizontal bars are arranged in a mesh shape on the upper portion of the protruding truss bar, and then concrete is placed on the half precast floor slab so that the vertical bar and the horizontal bar are also embedded together with the upper portion of the truss bar. It is characterized by In this case, it is also preferable to connect the upper part of the truss and the vertical and horizontal lines arranged in a mesh on the truss to each other.

According to the floor construction method of the present invention,
The lower part of at least one pair of truss bars formed by arranging deformed rebars having protrusions on the surface at upper and lower positions with a space, and winding the deformed bar for girder so as to spirally surround the upper and lower deformed rebars The half-precast floor slab, which is partially buried, is preliminarily formed and prepared in a manufacturing yard at a factory or on-site.

And, this half precast floor slab is
It is carried to a construction site by a transportation means such as a truck, or arranged directly from a production yard on the site at a position to be a floor. Since half-precast floor slabs already formed in the factory or on-site production yard are arranged in this manner, no support work is required. Then, arrange reinforcing bars as needed on the upper part of these half precast floor slabs, or connect the reinforcing bars and truss bars, etc., and then concrete is placed on it, and a floor of a predetermined thickness is formed. Form.

At that time, it is necessary to bury the upper portion of the truss bar projecting from the half precast floor slab in the poured concrete, which is designed in advance based on the completed thickness of the floor. You can leave it. For this reason, in the floor construction method of the present invention, it is not necessary to install the formwork and the work of arranging the bar as in the conventional case.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The floor construction method of the present invention will be described below in more detail with reference to the embodiments shown in the drawings. FIG. 1 shows a floor structure during construction based on a floor construction method according to an embodiment of the present invention.

In this floor structure, as shown in FIG. 2, a half precast floor slab 6 is used in which the lower part of the truss reinforcement 5 is partially embedded and the upper part is exposed from the surface. A large number of such half-precast floor slabs 6 are manufactured in advance in a factory or the like, and the half-precast floor slabs 6 are transported to a construction site by a truck or the like and arranged at a position to be a floor of a building without a gap.

As shown in FIG. 3, the truss reinforcement 5 is a deformed rebar 1 having nodal projections 4 formed on the surface thereof at predetermined intervals.
Are arranged at intervals in the vertical direction, and the deformed bar for girder 2 is wound so as to surround the deformed bar 1 in a spiral shape. This deformed bar for girder 2 is thinner than the deformed bar 1 for shape, and knot-shaped projections 15 are formed at predetermined intervals on the surface of the deformed bar for girder 2.

By the way, it has been explained that the truss bar 5 is formed by winding the deformed bar for girder 2 in a spiral shape around the outer periphery of two deformed bar 1 arranged at intervals. The winding shape of the deformed bar for girder 2 around the two deformed bars 1 as seen from the end side is a shape obtained by crushing a circle from both sides, as is clear from FIG.
Deformed bar 1 inside the vertical bending part of deformed bar 2 for girder
Is located.

In this way, the deformed bar 1 is surrounded by the deformed bar 2 for the girder, so that the two will not come off. In this state, there is play between the deformed bar 1 and the girder deformed bar 2. Therefore, if necessary, the contact portion between the deformed bar 1 and the girder deformed bar 2 is fixed with the adhesive 3. Is also preferable. However, this adhesion is not for ensuring the strength of the structure, but only for preventing the pieces from coming apart during handling.

As described above, unlike the conventional truss bar 5, the strength is not secured by welding, but the main bar is wrapped and restrained. Therefore, compression, tension,
It exhibits extremely strong proof stress against stress from all directions such as buckling and kinking, and can be used as a reinforcing bar for beams.

In the half precast floor slab 6 as described above, the truss bars 5 are arranged vertically with the lower part thereof being embedded in concrete. The half precast floor slab 6 is mass-produced by using a mold in a factory or the like.

The trusses 5 are slightly projected from both ends of the half precast floor slab 6 after curing so that they can be placed on an existing beam or the like at the construction site. In addition, in order to increase the strength in the half precast floor slab 6, the vertical streaks 10 and the horizontal streaks 11 are arranged in a mesh shape.

Since the truss reinforcement 5 is always installed in the vertical position in this manner, it is extremely strong against bending stress applied especially in the vertical direction, and the truss reinforcement 5 is basically constructed so as not to be disassembled. Therefore, it can be sufficiently used as a reinforcing bar in a portion exposed to extremely severe stress such as a floor.

A chamfered portion 6a is formed at a corner of the half precast floor slab 6. This is so that the precast concrete 6 can be dropped into a predetermined position without being caught by the adjacent half precast floor slabs 6 when the precast concrete 6 is placed on a beam or the like by a crane.

The thickness of this half precast floor slab 6 is
Since it is about 1/4 to 1/6 of the floor thickness after completion, it is about 1/4 in terms of weight and can be easily installed by a normal crane. Then, the half-precast floor slab 6 is sequentially laid in a space surrounded by beams (not shown) or the like without a gap. At this time, the half precast floor slab 6 is held by placing the ends of the truss bars 5 on a beam or the like. Subsequently, the vertical streaks 12 and the horizontal streaks 13 are arranged on the truss streaks 5 in a mesh shape.

Then, the hose 1 of the concrete mixer
Concrete 7 supplied from No. 4 is cast on the half precast floor slab 6. The floor is completed when the concrete 7 is cured. Even when excessive stress is applied to the floor, a part of the truss reinforcement 5 may be disengaged due to a longitudinal displacement between the deformed bar 1 and the girder deformed bar 2. Absent.

Conventionally, when assembling a reinforcing bar from the ground up, it was necessary to have a high level of working skill and assembling skill in accordance with the bar arrangement drawing and the working drawing. Since the fixed half precast floor slabs 6 are arranged and used as a formwork, the construction of the half precast floor slabs 6 is sufficient with a crane of normal capacity, and after installation, concrete is placed. Only by doing so, quick construction is possible.

Further, it is not necessary to have a high skill to read the design drawing into the bar arrangement drawing or the processing drawing, and it is possible to cope with the shortage of engineers. Furthermore, since no support work or formwork is required, it is possible to quickly install an industrial machine such as a generator in a fixed position downstairs. Also, the ceiling height is the same as that of the completed ceiling, so it does not hinder the work below.

In the floor construction method according to the above-described embodiment, two deformed bars 1 are arranged with a space above and below, but one or two deformed bars on the upper side are provided. The deformed reinforcing bar for girder may be spirally wound around the deformed reinforcing bar group having two triangular deformed reinforcing bars on the lower side and having a triangular or quadrangular sectional shape.

Further, in the truss reinforcement embedded in the half precast floor slab used in the floor construction method according to the embodiment shown in FIG. 1, only one deformed bar 2 for girder was used. As shown in FIG. 4, another deformed bar for girder 2 may be attached like a double thread. By doing so, the strength can be further improved.

[0032]

As described above, according to the floor construction method of the present invention, the half-precast floor slab formed by burying a part of the truss reinforcement is arranged at the position to be the floor of the building. After that, concrete was placed on this half precast floor slab to form the floor, so when constructing a thick concrete floor, reinforcement work and erection and removal of formwork and support work are performed. It has excellent effects such as no need and no special construction machine for construction.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a floor structure during construction based on a floor construction method according to an embodiment of the present invention.

FIG. 2 is a perspective view showing one half precast floor slab used in the floor construction method according to the embodiment of the present invention.

FIG. 3 is a partially enlarged perspective view showing a truss streak provided in the half precast floor slab shown in FIG. 2.

FIG. 4 is a perspective view showing another configuration of truss bars provided in the half precast floor slab used in the floor construction method of the present invention.

FIG. 5 is a side view showing a conventional floor construction process.

[Explanation of symbols]

 1 Deformed bar 2 Deformed bar for girder 3 Adhesive 4 Protruding part (uneven part) 5 Truss bar 6 Half precast floor slab 7 Concrete 12 Vertical bar 13 Horizontal bar

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Keiki Kobayashi 2-10-26 Fujimi, Chiyoda-ku, Tokyo Maeda Construction Industry Co., Ltd. (72) Inventor Yuzo Ichijo 2- 10-26 Fujimi 2-chome, Chiyoda-ku, Tokyo Maeda Construction Industry Co., Ltd. (72) Inventor Shinji Kato 2-10-26 Fujimi, Chiyoda-ku, Tokyo Maeda Construction Industry Co., Ltd. (72) Inventor Yuji Hirota 2--10-26 Fujimi, Chiyoda-ku, Tokyo Maeda Corporation

Claims (3)

[Claims] 1. At least one set formed by arranging deformed rebars having irregularities on the surface at upper and lower positions with a space and winding the deformed rebars for girder so as to surround the upper and lower deformed rebars in a spiral shape. Pre-forming and preparing a half precast floor slab partially embedding the lower part of the truss bars, and then arranging at least one or more of the half precast floor slabs at a position to be a floor of a building After that, the method for constructing a floor is characterized in that it is constructed by pouring concrete on the half precast floor slab so as to bury the upper portion of the truss reinforcement protruding from the half precast floor slab. 2. A plurality of the truss bars are attached to one of the half precast floor slabs, and the half precast floor slabs are arranged at a position to be a floor of a building and then protrude from the half precast floor slab. A vertical streak and a horizontal streak are arranged in a mesh on the upper part of the truss streak, and then concrete is placed on the half precast floor slab so that the vertical streak and the horizontal streak are also embedded together with the upper part of the truss streak. The floor construction method according to claim 1. 3. The floor construction method according to claim 2, wherein upper portions of the truss reinforcements and vertical reinforcements and transverse reinforcements arranged in a mesh on the truss reinforcements are connected to each other.