JPH0241615B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a construction method for constructing slabs between girders.

[Prior art]

When constructing a slab between the girders, the general method is to place formwork across the entire surface between the girders, support the formwork from below with shoring, and pour concrete. In this case, it has been often attempted in recent years to construct the formwork as a waste formwork using a deck plate or an Omnya plate (trade name).

On the other hand, in the case of this type of construction method, small beams are usually installed to strengthen the support of the slab, but since the small beams protrude from the bottom of the slab, if this is not desired, the void slab method is used. Sometimes. According to the void slab construction method, the utilization rate of space can be increased.

[Problem that the invention seeks to solve]

In the conventional construction method mentioned above, construction costs are reduced by using deck plates and omni-plates as formwork, but since temporary members such as shoring are used, there is still sufficient economic effect. We haven't reached that point yet.

The present invention allows slabs to be constructed without small beams, eliminates temporary supports, etc., and reduces construction costs.
The purpose of the present invention is to provide a method for constructing a slab that not only increases the ratio but also takes into consideration workability, strength, etc.

[Means for solving problems]

In the present invention, in order to solve the above-mentioned problems, first, a PC plate that also serves as a formwork is provided on the lower surface between the girders, and a truss in which the lower chord material is embedded in the PC plate is arranged above the PC plate. By spanning composite beams,
A slab lower formwork is constructed from a PC plate, and a void forming pipe with an oval cross section is placed between each truss on the PC plate, and then the truss and the void forming pipe are filled in the area. It is characterized by constructing a slab by pouring concrete onto a PC board.

[Example] An example of the present invention will be described with reference to the drawings.

Figure 1 is a plan view of the object on which a slab is to be constructed, and 1 and 2 in the figure are girders. In constructing a slab between these girders 1 and 1 (or between 2 and 2), in this embodiment, first a composite beam 3 as shown in FIGS. 2 and 3 is installed between these girders 1 and 1 as shown in FIG. As shown by the two-dot chain line, multiple lines are laid in parallel. This composite beam 3 consists of the PC version 4 and the 2
It consists of a truss 5 that is parallel to the book, and the truss 5 includes an upper chord member 5a, a lower chord member 5b embedded in the PC plate 4,
and a lattice 5c. 6 is a reinforcing bar.

In the composite beam 3, the upper chord member 5a is made longer than the lower chord member 5b, so that it can be easily spanned over the girder 1. Further, the size of the PC plate 4 is set to an appropriate width and length from the viewpoint of girder spacing and workability.

As shown in Fig. 5, in the case of SRC construction, the method of spanning this composite beam 3 over the girders 1, 1 is to directly span the top chord 5a on the girder steel frame 7, and in the case of RC construction, the side of the girder 1. The PC plate 4 may be placed on the crosspiece 9 of the formwork 8. Note that FIG. 5 shows both cases.

In this way, by spanning the composite beams 3 so that the PC versions 4 of each composite beam 3 are in close contact with each other,
Construct the slab lower formwork using PC version 4. At this time, the spacing between each truss 5 is set to be constant, with a standard value of about 40 to 70 cm, but this spacing may be determined in accordance with the girder spacing and the structure of the slab.

Further, while the composite beam 3 is being constructed, a void forming pipe 10 having an oval cross section is placed between each truss 5 on the PC board 4. The length direction of the pipe 10 is aligned with the length direction of the truss 5, and the pipe 10
The cross section of should be long horizontally.

As the void forming pipe 10, for example, one manufactured as follows is used. First, a flexible pipe 11 as shown in FIG.
Open. On the other hand, a small-diameter pipe is cut into required dimensions to make a spacer 12 as shown in FIG.
Next, as shown in FIG. 8, this spacer 12 is inserted into the pipe 11, and the bolt 13 is inserted into the pipe 11.
1 through the hole 11a and the spacer 12, and tighten the bolt 13 to crush the pipe 11 in the diametrical direction. This is how it was produced.

After placing the void forming pipe 10, reinforcing bars 14 are placed on the truss 5 and the pipe 10, and concrete 15 is placed together with the girder to complete the slab.

By doing this, it is possible to construct a lightweight slab without shoring and without small beams.

〔Effect of the invention〕

According to the present invention, when constructing a slab between the girders, a composite beam consisting of a truss and a PC plate is first spanned between the girders, a slab lower formwork is constructed using the PC plate, and at the same time, a composite beam is constructed by combining a truss and a PC plate. A pipe with an oblong cross section is placed to form a void, and concrete is poured on top of it to complete the slab, so there is no need for support such as temporary supports.
Moreover, a lightweight slab can be realized, and construction costs can therefore be reduced. Additionally, since there are no small beams, it is possible to lower the floor height and increase space utilization. Furthermore, since a void forming pipe with an oval cross section is used, it is possible to construct a lightweight slab with a higher porosity than conventional void slabs. Further, especially according to the present invention, since the void forming pipe has an oval cross section, it is possible to sufficiently fill the poured concrete to the bottom surface of the void forming pipe when pouring concrete. Since this void-forming pipe has an oval cross section, it is more stable when installing it on the PC board, and therefore the positioning work is easier than using a perfectly circular pipe. It is easy to carry out, and in addition, since it has an oval cross section and is elongated horizontally, the number of pieces to be installed can be reduced accordingly, resulting in extremely good workability.

In addition, in the case of a flat square pipe, the area where the bottom surface comes into contact with the PC plate becomes large, resulting in a reduction in the contact area between the PC plate and the cast-in-place concrete. The adhesion area of cast-in-place concrete is reduced, resulting in a loss of integration over a larger area of both sides, but since the present invention has an oval cross section, such problems do not occur, and the strength is increased. It is also extremely good from a design point of view.

[Brief explanation of drawings]

The drawings are for explaining one embodiment of the present invention, and FIG. 1 is a plan view of the object on which a slab is to be constructed, FIG. 2 is a front view of a composite beam, FIG. 3 is a side view of the same, and FIG. Figure 4 is a front view to explain the construction procedure.
FIG. 5 is a side view of the same, and FIGS. 6 to 8 are views for explaining an example of manufacturing an elliptical void-forming pipe. 1, 2...Large beam, 3...Composite beam, 4...PC version,
5...Truss, 5b...Lower chord material, 10...Void forming pipe.

Claims (1)

[Claims] 1. When constructing a slab between the girders, a composite beam consisting of a PC board that also serves as formwork on the lower surface and a truss with the lower chord embedded in the PC board above the PC board is installed between the girders. All the PCs
The slab forms the lower formwork of the slab, and at the same time, a void forming pipe with an oval cross section is placed between each truss on the PC plate, and then the truss and the void forming pipe are filled in the area.
A slab construction method characterized by pouring concrete onto a PC board.