JP3041754U - Half precast slab - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To provide a half precast slab capable of simplifying on-site work before placing concrete by omitting the work of installing concrete damming means at a construction site. SOLUTION: A half precast plate used in a method of forming pillars 30, beams 31, and slabs 32, 33 with concrete having different strengths, which blocks the flow of cast-in-place concrete 20 cast on the half precast plate. The damming means 11 for forming was embedded and formed in the precast concrete so as to project onto the half precast plate. The damming means 11 includes a concrete portion 11a and an end portion 11 embedded in the concrete portion.
b'can be formed with the protruding reinforcing bar 11b, and such damming means is arranged so that a part of the concrete portion and the protruding end of the reinforcing bar are integrally embedded in the precast concrete 12. To do.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a half precast slab used in a method of forming columns, beams, and slabs with concrete having different strengths.

[0002]

[Prior art]

For each part of columns, beams and slabs, concrete with different compressive strength may be poured to construct the frame. For example, when building a high-rise building with a reinforced concrete structure, it may be required to form structural columns with concrete of 600 kgt / cm ² or more. At this time, the beam and the slab attached to this beam are It is often required that a part of the concrete should be cast with a weight of about 420 kgt / cm or more, and that the slabs other than the beam-attached part should be cast with a weight of 420 kgt / cm ² or less.

In such a construction method of constructing a floor slab by using half precast plates having reinforcing bar trusses arranged therein, concrete having different strengths is separately cast into each part, and in the conventional method, half precast plates are used as pillars or beams. After arranging on the formwork, at the construction site, a mesh streak or pipe bundle is tied at the boundary between the beam slab of the half-precast plate and the floor slab. It was blocking the concrete that was about to flow into the slab.

[0004]

[Problems to be solved by the device]

 In the concrete damming means described above, since the mesh reinforcement or the bundle of pipes must be bound at the construction site, there is a problem that the on-site work before placing the concrete becomes complicated.

The present invention has been made to solve the above problems, and the problem is that it is not necessary to attach concrete damming means at the construction site, and it is possible to simplify the site work before concrete placement. It is to provide a half-precast slab that can.

[0006]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention is a half precast plate used in a method of forming columns, beams, and slabs with concretes having different strengths, which is a cast-in-place concrete cast on the half precast plate. A damming means for damming the flow provides a half precast slab formed so as to be embedded in the precast concrete so as to project on the half precast plate.

In the half precast slab of the present invention, the damming means can be formed by a concrete part and a reinforcing bar which is embedded in the concrete part and has an end protruding from the concrete part. A part and the protruding end of the reinforcing bar are arranged so as to be integrally embedded in the precast concrete.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a partial cross-sectional view showing a part of the half precast slab of the present invention, and FIG. 2 (a) shows the layout relationship of the half precast slab, columns and beams of the present invention, and therefore a part thereof is omitted. FIG. 2 (b) is a partial plan view for explaining the positional relationship between the truss reinforcement 13 omitted in FIG. 2 (a) and the blocks 11a, 11b, 11c. Fig. 2 is a partial plan view, Fig. 2 (c) is a sectional view taken along the alternate long and short dash line IIc-IIc in Fig. 2 (a), and Fig. 3 is a state in which cast-in-place concrete is placed on the half precast slab of the present invention. FIG.

In FIG. 1, the half precast slab 10 of the present invention has lower end bars 14 and 15 arranged so as to intersect in a perpendicular direction on its form (not shown). The truss bars 13 are arranged on the upper end 15 and the block 11 formed in advance as a damming means is arranged on the lower end bars 14 and 15, and the lower end bars 14 and 15 and the lower ends of the tras bars 13 are arranged. And the lower end of the block 11 are integrally embedded and formed in the precast concrete of the flat plate portion 12. Here, as shown in FIG. 1, the block 11 is formed such that the concrete portion 11a is formed in a rectangular cross section and extends in the arrangement direction, and the reinforcing bar 11b is formed in the concrete portion 11a. , 11c are embedded, the reinforcing bars 11c are arranged so as to extend in the arrangement direction of the block 11, and the reinforcing bars 11b are L-shaped so that the end portions 11b 'project from the concrete portion 11a. Place a plurality of bars at specified intervals. Further, the protruding direction of the end portion 11b 'and the reinforcing bar 11b arrangement interval are appropriately determined so that each end portion 11b' can be bound to the lower end rib 15 of the flat plate portion 12 by the wire 16. Further, the height of the block 11 is determined so that the upper end thereof is located slightly lower than the upper end of the truss bar 13. Furthermore, as shown in FIG. 3B, the lengths and planar shapes of the blocks 11A, 11B, 11C can be appropriately determined according to the arrangement of the truss reinforcements 13.

The trusses 13 of the flat plate portion 12 are formed by connecting the upper chord member 13a and the lower chord members 13c and 13c with the lattice member 13b, and the lower chord members 13c and 13c and the lower end of the lattice member 13b are connected to each other. The reinforcement is arranged so as to be embedded in the flat plate portion 12.

2 (a) to (c) and FIG. 3 are shown for the operation when the above half precast slab 10 is used in the method of forming the columns, the beams and the floor slab with concrete having different strengths. It will be described with reference to FIG. For example, when constructing a high-rise building with a reinforced concrete structure, 600 kgt / cm ² or more of concrete is placed on the structural columns 30, and 420 kgt / cm or more of concrete is placed on the beams 31 and the beam slabs 32. In addition, floor slabs 33 other than the beam-attached slab 32 may be required to be cast with concrete of 270 kgt / cm ² or more. When the above half precast slab 10 is used for such a frame, as shown in FIG. 2 (c), the beam form 35 and the column form (not shown) are supported while being supported by the supporting structure 36. After assembling, the half precast slab 10 is arranged on the beam form 35 and the column form, and the upper end lines 17 and 18 are arranged on the truss line 13 and the block 11 of the half precast slab 10. To do. Then, first, concrete of 600 kgt / cm ² or more is placed in the pillar formwork and hardened to a predetermined strength or more, and then 420 kgt / cm or more in the beam form frame 35 and the beam slab 32 portion. Place the concrete of.

At this time, the cast-in-place concrete of the beam-attached slab 32 and the floor slab 33 is provided on the block 11 as shown in FIG. 3 in order to obtain a sufficient covering thickness on the upper end bars 17 and 18. Although it is cast to a higher position, most of it is blocked by the block 11 due to the consistency of the beam concrete 20 itself, and the outflow to the floor slab 33 is suppressed to a minimum.

Next, when the concrete 20 for beam is hardened to a predetermined strength or more, concrete of 270 kgt / cm ² or more is placed on the floor slab 33 portion, and concrete having different compressive strength is applied to each pillar, beam and floor slab. The division is completed.

[0015]

[Effect of the invention]

 According to the present invention, the damming means for damming the flow of cast-in-place concrete is embedded in the precast concrete in advance so as to project onto the half precast plate to form the half precast slab. It has become possible to simplify complicated work such as installing cleat blocking means.

Further, in the present invention, the damming means comprises a concrete part and a reinforcing bar embedded in the concrete part and projecting at an end thereof. A part of the concrete part and a protruding end of the reinforcing bar are made of precast concrete. By embedding it inside, it is possible to easily form a half precast slab with good integration between the damming means and the precast concrete. This not only simplifies the work at the construction site, but also simplifies the work when manufacturing the half precast slab.

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing a part of a half precast slab of the present invention.

FIG. 2 (a) is a plan view showing a layout relationship of a half precast slab, a column and a beam of the present invention in a simplified manner with a part omitted, and FIG. 2 (b) is a diagram showing truss bars and blocks. It is a fragmentary top view for demonstrating arrangement relation, (c) is sectional drawing which follows the dashed-dotted line IIc-IIc in (a).

FIG. 3 is a partial cross-sectional view showing a state where cast-in-place concrete is cast on the half precast slab of the present invention.

[Explanation of symbols]

 10 Half precast slab 11 Block (damming means) 11a Concrete part 11b Reinforcing bar 11b 'Reinforcing bar end 12 Flat plate part (precast concrete) 20 Beam concrete (cast-in-place concrete) 30 Column 31 Beam 32 Beam slab with beam (slab) ) 33 Slabs

Claims (2)

[Utility model registration claims] 1. A half precast plate used for a method of forming columns, beams and slabs with concrete having different strengths, which is a dam for blocking the flow of cast-in-place concrete cast on the half precast plate. A half precast slab formed by being embedded in precast concrete so that the means projects above the half precast plate. 2. The damming means comprises a concrete part,
A reinforcing bar embedded in the concrete part and having an end projecting, and a part of the concrete part and a projecting end of the reinforcing bar being buried in the precast concrete. Half-precast slab described.