JPH05263526A - Construction method of rc construction beam - Google Patents

Abstract

PURPOSE:To make unnecessary a post downward of a beam form and to make it possible to shorten a construction period. CONSTITUTION:A trussed built-up reinforcement A consisting of upper main bars 1a and lower main bars 1b of beams, a stirrup 2 fixed and wound on the peripheral surfaces of them and zigzag lattice bars 3 provided in a state to connect upper and lower bending sections (a) and (b) between the upper main bars 1a and the lower main bars 1b to the upper and lower main bars 1a and 1b is built in a specific position. A horizontal members 7 is suspended and borne on the trussed built-up reinforcement A through hanger members 6 interlocked with joining sections of the lower bending section (b) of the lattice bars 3 with the lower main bars 1b, and a concrete C is placed in a beam form B in a state to bear the beam form B with the horizontal member 7.

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 RC beams.

[0002]

2. Description of the Related Art Conventionally, RC beams are used to support the load of the beam form by means of a steel pipe joist and a large tow placed under the beam form, and a support structure including a large number of posts supporting the large tow. It was constructed by placing concrete in the beam formwork in this state. Therefore, below the beam, concrete will develop a certain level of strength, and many posts will stand up until the mold is removed, and these posts will become obstacles to the work on the lower floors. However, there is a problem that the construction period becomes longer because the materials cannot be transported quickly.

[0003]

SUMMARY OF THE INVENTION The present invention has been made with the above points in mind. The object of the present invention is to eliminate the need for a post below the beam formwork and to shorten the construction period.
It is to provide a method of constructing a C beam.

[0004]

In order to achieve the above-mentioned object, the technical means taken by the present invention are as follows. That is, in the method of constructing an RC beam according to the present invention, an upper main bar and a lower main bar of a beam, a stirrup wrapped around and fixed to the outer peripheries of the beam, and upper and lower bent portions are provided between the upper main bar and the lower main bar. A truss-shaped assembly rebar having zigzag-shaped lattice reinforcements connected to upper and lower main reinforcements is installed at a predetermined position, and the bent portion below the lattice reinforcement and the lower main reinforcement are attached to the truss-shaped assembly reinforcement. An RC beam is constructed by suspending and supporting a horizontal member via a suspending member that is locked to the joint portion with and placing concrete in the beam formwork while supporting the beam formwork with the horizontal member. It is characterized by doing.

In the above construction method according to the present invention, as is clear from the embodiments described later, in the case where the truss-shaped assembly rebar is erected at a predetermined position and the beam form is supported by the truss-shaped assembly rebar. And the case where the beam formwork is supported by the truss-shaped assembled reinforcing bar in advance by work on the floor surface, and then the truss-shaped assembled reinforcing bar is installed at a predetermined position.

[0006]

According to the above construction, since a zigzag lattice reinforcement is provided between the upper main reinforcement and the lower main reinforcement of the beam to form a truss-shaped rebar, sufficient rigidity can be obtained for the rebar. Since the suspension member is locked at the joint between the bent portion below the lattice reinforcement and the lower main reinforcement, the weight of the beam form and the concrete cast therein can be supported by the assembled rebar. Therefore, a post for supporting the beam formwork is not required, and various works and material transportation on the lower floor can be easily and safely performed without being disturbed by the post.

[0007]

1 to 4 show an embodiment of a method for constructing an RC beam according to the present invention. In the figure, A is a truss-shaped assembled rebar embedded in an RC beam as a beam. The truss-shaped assembly rebar A is pre-assembled by factory processing,
The upper and lower main bars 1a and 1b of the beam, the stirrup 2 wound around and fixed to the outer peripheries thereof, and the upper and lower bent portions a and b between the upper main bar 1a and the lower main bar 1b are the upper and lower main bars 1a. , 1b and zigzag-shaped lattice muscles 3 provided in a state of being joined to the same. Joining and fixing of each part of the reinforcing bar is performed by welding or the like.

The RC beam construction procedure is as follows.
The truss-shaped assembled rebar A was previously worked by working on the floor.
Then, the horizontal member 7 in the beam width direction is suspended and supported via the suspending member 6 that is locked to the joint between the bent portion b below the lattice muscle 3 and the lower main reinforcement 1b. The hanging member 6 is, for example, a U bolt and a nut, and the horizontal member 7 is, for example,
Square steel pipes are used. Scaffolding plates 8 are erected near the ends of the horizontal member 7, and columns 10 of handrails 9 are erected at both ends. As shown in the figure, the use of separate hanging members 6 for each lower main bar 1b prevents deformation of the lower main bars 1b at both ends toward the center of the beam due to the weight of concrete and inclination of the scaffolding plate 8 due to the deformation. Effective above.

Next, the truss-shaped assembled rebar A is hung at a predetermined position by a lifting machine (not shown), and as shown in FIG.
It is erected on the beam steel frames 11, 11 of the large beam, and both ends of the upper main bar 1a are fixed to the brackets 12, 12 welded to the upper flanges of the beam steel frames 11, 11 by welding.

Thereafter, the beam form B made of plywood or the like is assembled by the work on the scaffolding plate 8. The form separator and the form tie are omitted in the drawing.

Next, concrete C is placed inside the beam form B. When the concrete C hardens, a stepladder or the like is installed on the floor surface of the lower floor to remove the horizontal member 7, and the mold is removed to complete the construction of the RC beam.

The whole or part of the beam form B (for example, the beam bottom form) may be supported on the horizontal member 7 in advance by working on the floor. The lower end portion of the hanging member 6 exposed on the concrete surface of the beam bottom may be covered with a ceiling plate (not shown) or cut out. A driving mold may be used as the beam mold B, and the demolding step may be omitted. Figure 2
D is a floor formwork of a known structure that does not require support and is composed of a steel plate driving formwork for the floor and a one-way truss bar integrally provided on the upper surface of the formwork. It is laid across the upper main reinforcement 1a of A and the beam steel frame 11 of the SRC large beam.

FIG. 5 shows another embodiment of the present invention. In this embodiment, the horizontal member 7 has a length substantially equal to the beam width, the beam member B is supported by the horizontal member 7, and the hanging member 13a, the horizontal frame 13b, and the horizontal frame 13b are provided below the horizontal member 7. It is characterized in that a suspension scaffold 13 composed of a scaffold plate 13c and handrails 13d supported on both end sides is provided. The other structure is the same as that of the above-mentioned embodiment, and the description thereof will be omitted.

FIG. 6 shows another embodiment of the present invention. In this embodiment, the horizontal member 7 has a length substantially equal to the beam width, and the beam form B is entirely assembled in advance in a state of being supported by the horizontal member 7 by a work on the floor. The feature is that the assembled rebar A is suspended and installed at a predetermined position. The other structure is the same as that of the above-mentioned embodiment, and the description thereof will be omitted.

[0015]

EFFECTS OF THE INVENTION The present invention has the above-described structure, and since a zigzag-shaped lattice reinforcement is provided between the upper main reinforcement and the lower main reinforcement of a beam to form a truss-shaped assembled reinforcing bar, sufficient rigidity can be obtained for the assembled reinforcing bar. In addition, since the suspension member is locked at the joint between the bent portion below the lattice reinforcement and the lower main reinforcement, the weight of the beam formwork and the concrete cast therein is supported by the assembly reinforcement. You can Therefore, the posts that support the beam formwork are not needed, and there are no obstructive posts.Therefore, when the construction of the beam formwork is completed, it is possible to immediately start various works on the lower floor and material transportation. It is possible and the construction period can be shortened.

[Brief description of drawings]

FIG. 1 is an overall schematic side view showing an embodiment of the present invention.

FIG. 2 is an overall schematic cross-sectional view in a direction perpendicular to the RC beam making.

FIG. 3 is a perspective view of a main part.

FIG. 4 is a sectional view of a main part.

FIG. 5 is a cross-sectional view of a main part showing another embodiment of the present invention.

FIG. 6 is a sectional view of a main part showing another embodiment of the present invention.

[Explanation of symbols]

A ... Truss-shaped assembly rebar, B ... Beam form, C ... Concrete, 1a ... Upper main bar, 1b ... Lower main bar, 2 ... Star wrap,
3 ... lattice lines, 6 ... hanging member, 7 ... horizontal member.

Claims (1)

[Claims] 1. An upper main bar and a lower main bar of a beam, a stirrup wrapped around and fixed to the outer peripheries thereof, and upper and lower bent portions are joined to the upper main bar and the lower main bar between the upper main bar and the lower main bar. A truss-shaped assembly rebar having a zigzag-shaped lattice bar provided in a state is erected at a predetermined position, and the truss-shaped rebar is locked at the joint between the bent portion below the lattice and the lower main bar. An RC construction in which a horizontal member is hung and supported via a suspension member, and concrete is placed in the beam form while the beam form is supported by the horizontal member to construct an RC beam. How to build a beam.