JPH0469688B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a method of constructing columns and beams in a reinforced concrete structure or a steel reinforced concrete structure.

"Prior Art and its Problems" Recently, when constructing a reinforced concrete structure or a steel-frame reinforced concrete structure, a construction method using precast formwork that incorporates main reinforcement and shear reinforcement inside has been implemented.

The construction method using precast formwork as described above involves casting a concrete formwork with built-in reinforcing bars in advance at a factory, etc., transporting it to the construction site, installing it at a designated location, and pouring concrete inside. However, after the concrete hardens, the formwork will remain intact and used as part of the structure without being dismantled. This method provides various advantages, such as eliminating the need to dismantle the formwork, making it easier to assemble the formwork, and reducing the work required to arrange reinforcement within the column and beam formwork on site. .

However, in the conventional construction method using precast formwork mentioned above, the reinforcement for columns and beams is actually assembled on-site, which is labor-intensive and requires work in a narrow space. It was difficult to obtain a certain level of accuracy, and it was desired to simplify the reinforcement work in this area.

The present invention has been made in view of the above circumstances, and aims to provide a construction method for columns and beams in a concrete structure, which allows reinforcement work for columns and beams to be easily performed in a short time and with high precision. purpose.

"Means for solving the problem" In order to achieve the above purpose, the construction method of the present invention has the following features:
Inside the hollow concrete column formwork body extending in the vertical direction, shear reinforcing bars are placed on the outside of a plurality of column main reinforcements at predetermined intervals in the length direction of the column main reinforcements, except near the ends of the column main reinforcements. A precast column form is erected in which a coiled column reinforcing bar is provided along the inner surface of the column form main body, while a plurality of hollow concrete columns extending laterally with the openings facing upward are installed. A precast beam formwork is erected by supporting one end of the main body of the beam formwork made of steel on each required side of the upper end of the main body of the column formwork, and on the other hand, supporting the main column reinforcing bars overlapping with the above-mentioned column reinforcing bars and the entire length thereof. For assemblies of reinforcing bars with shear reinforcing bars placed at predetermined intervals.For column reinforcing bars, main beam bars forming the ends of beam bars, and for assemblies of reinforcing bars with shear reinforcing bars placed at predetermined intervals over the entire length of the main beam bars. A reinforcing bar assembly is pre-assembled in which the beam reinforcing bars are arranged so as to extend in directions orthogonal to each other and collectively connected at the intermediate part of the column reinforcing bars for the reinforcing bar assembly, and the pre-assembled reinforcing bar assembly is The column reinforcing bars for reinforcing bar aggregates are set in the precast column form by dropping the beam reinforcing bars for reinforcing bar aggregates into the precast beam form, and each column main bar in the precast column form and the reinforcing bars are set. The main reinforcement bars of the column reinforcing bars for the assembly are overlapped each other by a predetermined length and connected, and the main reinforcements of each intermediate portion of each beam and the main beam reinforcement of the beam reinforcement for the reinforcing bar assembly are overlapped each other by a predetermined length within the precast beam formwork. At the same time, a shear reinforcing bar is arranged in the middle of the beam, and a frame-like formwork is installed between the ends of the precast beam formwork to close the gap between the precast column formwork and the precast beam formwork. The structure is such that concrete is poured into parts and the parts are molded into one piece.

"Embodiments" Hereinafter, each embodiment of the present invention will be described with reference to the drawings.

Figures 1 and 2 are diagrams showing an example in which the present invention is applied when constructing a pillar located at the center of a building and a beam connected thereto.In this example, the pillar to be constructed has a wall section. are not connected.

When constructing the columns and beams, first, the precast column form 1 is erected at a predetermined position on the slab.
As explained in the conventional example, the precast column form 1 is formed in advance in a factory or the like to a specified size and shape, and is a concrete column form main body having a rectangular cross section. 11, and column reinforcing bars (including both column main bars and shear reinforcing bars) 12 attached to their inner surfaces. Among the column reinforcing bars 12, a plurality of column main reinforcing bars are provided in parallel in the length direction of the column formwork body 11, and shear reinforcing bars are provided outside of the column main reinforcing bars with column reinforcing bars for reinforcing bar aggregates to be described later. They are provided in a coiled manner in a direction perpendicular to the column main reinforcement at a predetermined interval in the length direction of the column main reinforcement except for the overlapping portion (near the side end of the column main reinforcement).

Next, the precast beam form 2 is set so as to be perpendicular to the column form main body 11, with one end supported at the center of each side of the upper end of the precast column form 1. At this time, the other end side of the precast beam form 2 is supported by a precast column form (not shown).
The precast beam formwork 2 is formed in advance in a factory, etc., like the precast column formwork 1, and is made of concrete beam formwork body 2 with a U-shaped cross section.
1 and is set with its opening facing upward.

After completing the erection of the precast column formwork 1 and the precast beam formwork 2 as described above, next, a reinforcing bar assembly 3 preassembled in a factory is set on both of them.

This reinforcing bar assembly 3 consists of three sets of column reinforcing bars for reinforcing bar assemblies, one set of column reinforcing bars for reinforcing bar assemblies, and two sets of beam reinforcing bars for reinforcing bar assemblies, each extending in three axial directions perpendicular to each other in accordance with the columns and beams to be constructed. It is made of reinforcing steel. The column reinforcing bars for the reinforcing bar assembly have the same configuration as the column reinforcing bars in the column form main body 11, and are placed outside the plurality of column main reinforcing bars 31 at predetermined intervals in the length direction of the column main reinforcing bars 31. A plurality of hoop reinforcements (shear reinforcing reinforcements) 33 are wound over the entire length in a direction perpendicular to the reinforcing bars 31.

In addition, the beam reinforcing bars for the reinforcing bar aggregate are multiple beam main bars 32.
A plurality of stirrups (shear reinforcing bars) 34 are wound on the outside of the main beam reinforcement 32 at predetermined intervals in the length direction of the main beam reinforcement 32 in a direction perpendicular to the main beam reinforcement 32. The main column reinforcing bars 31 and the main beam reinforcing bars 32 constitute a set of four main pillar reinforcing bars or four main beam reinforcing bars, each of which is provided at the apex of a rectangle and extending parallel to each other. and,
As shown in FIG. 1, the reinforcing bar assembly 3 constructed in this manner is dropped into the precast column formwork 1 and the precast beam formwork 2 from above and set at a predetermined position.

In the reinforcing bar assembly 3, the horizontal or vertical spacing between the column main reinforcements 31 or between the beam main reinforcements 32 and the mutual spacing between the shear reinforcing bars 33 and 34 are the same as those of the precast column formwork 1 and the precast beam formwork 2. Determined by size, required strength, etc.

In addition, the length of the column main reinforcements (see Fig. 2) in the precast column formwork 1 is set so that they overlap with each column main reinforcement 31 of the reinforcing bar assembly 3 that will be set later, and After setting the three reinforcing bars inside, the beam main reinforcements 22a and shear reinforcement bars (these shear reinforcements are placed outside each beam main reinforcement 22a at a predetermined interval in the length direction of the beam main reinforcements 22a). ) 22 is arranged in a coiled manner perpendicular to the main reinforcement 22a. This main beam reinforcement 22a is appropriately arranged so that its length overlaps with the main beam reinforcement 32 of the reinforcing bar assembly 3 that will be set later. After the three reinforcing bar assemblies are set, the overlapping main reinforcing bars are connected using fixing means such as binding bars or welding.

In this way, after setting the pre-assembled reinforcing bar assembly 3 in the precast column formwork 1 and the precast beam formwork 2, the floor formwork (not shown) is assembled between the precast beam formworks 2, and as a matter of course, , between the ends of each precast beam form, a corner of the column form main body 11 for closing the gap between the precast column form 1 and the precast beam form 2 is placed in the length direction of this column form main body 11. A formwork (not shown) having an elongated shape (L-shape) is provided, and then concrete is poured into this formwork, the column formwork 1, the beam formwork 2, and the floor formwork to form a column. , beams and floors can be cast and molded as one piece. At this time, if mesh is placed on the inner surface of the precast column formwork 1 and the precast beam formwork 2, the column formwork body 11 and the beam formwork body 21
It is possible to increase the bonding strength between concrete and newly placed concrete.

In the manner described above, the columns, beams, intersections between the two, and the floor can be integrally cast and formed with concrete.

On the other hand, Figures 3 to 5 show examples in which the present invention is applied to constructing columns and beams that connect with external walls. Using the formed precast column form 5, the column form 5 is arranged so that the opening faces the precast outer wall form 6 (see FIG. 5). Also,
When making a beam that extends in contact with an external wall, the precast beam form 7 is an L-shaped cross section in which reinforcing bar aggregates 35 and beam reinforcing bars 8, which will be described later, are arranged. are arranged so that the opening faces upward and toward the precast outer wall formwork 6. A precast beam form 9 used to make a beam perpendicular to the external wall form 6 has the same structure as the beam form 2 shown in FIGS. 1 and 2 above.

The previously assembled reinforcing bar assembly 35 is set on the precast column formwork 5 and the precast beam formworks 7 and 9 assembled in this way. In this case, as in the above-described embodiment, after the reinforcing bar aggregate 35 is set, the main column reinforcing bars in the column formwork 5 and the beam forms 7 and 9, the beam main reinforcing bars and each column main reinforcing bar in the preassembled reinforcing bar aggregate 35, The beam main reinforcements are overlapped and connected using fixing means such as welding.

Next, as in the previous embodiment, a floor formwork is placed between the precast beam forms 7 and 9, and the precast beam forms 7 and 9 are placed between the precast beam forms 7 and 9.
A formwork is installed between the end of the column 9 and the precast column formwork 5 to close the gap, concrete is poured, and the column, beam, both, and the floor are integrally poured and formed. Note that S in FIGS. 4 and 5 indicates a separator.

"Effects of the Invention" According to the method for constructing columns and beams according to the present invention, pre-assembled reinforcing bar assemblies are precast, column reinforcing bars for reinforcing bar assemblies are precast, and beam reinforcing bars for reinforcing bar assemblies are precast in the column formwork. Set it by dropping it into the beam formwork, and connect it to each column main reinforcement in the precast column formwork.
The main reinforcement bars of the column reinforcing bars for reinforcing bar assemblies are overlapped each other by a predetermined length and connected, and the main reinforcements of each beam intermediate section and the main beam reinforcement of the beam reinforcing bars for reinforcing bar assemblies are overlapped each other by a predetermined length within the precast beam formwork. At the same time, a shear reinforcing bar is arranged in the middle of the beam, and a frame-like formwork is installed between the ends of the precast beam formwork to close the gap between the precast column formwork and the precast beam formwork. By pouring concrete into the parts and molding them into one piece, we ensured sufficient strength at the intersections of columns and beams, and the troublesome reinforcing work at the intersections of columns and beams could be done on-site. It can be performed in a narrow space in a short time, with high precision, and extremely easily.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing one embodiment of the method for constructing columns and beams according to the present invention, Fig. 2 is a perspective view showing the state in which the reinforcing bar assembly is incorporated, and Fig. 3 is a perspective view showing an example of the method for constructing columns and beams according to the present invention. FIG. 4 is a sectional view taken along the - line in FIG. 3, and FIG. 5 is a sectional view taken along the - line in FIG. 3. 1, 5... Precast column formwork, 2, 7, 9...
... Precast beam formwork, 3, 35 ... Rebar aggregate, 11 ... Column formwork body, 12 ... Reinforcement bar for column, 2
1... Beam formwork body, 22... Beam reinforcing bars, 31...
Column main reinforcement, 22a, 32...Beam main reinforcement, 33...Hoop reinforcement (shear reinforcement), 34...Start reinforcement (shear reinforcement).

Claims (1)

[Scope of Claims] 1. Shear reinforcing bars are installed at predetermined intervals in the length direction of a plurality of column main reinforcements on the outside of a plurality of column main reinforcements in a hollow concrete column formwork body extending in the vertical direction. A precast column form is erected, in which a column reinforcing bar is wound around the column except near the ends, along the inner surface of the column form main body, and a hollow column with the opening facing upward is installed. A precast beam form is erected by supporting one end of each of a plurality of concrete beam form bodies extending in the transverse direction on each required side of the upper end of the column form body; Column reinforcing bars for reinforcing bar aggregates with shear reinforcing bars arranged at predetermined intervals along their entire length, main beam bars forming the ends of beam bars, and shear reinforcing bars arranged at predetermined intervals along the entire length of the main beam bars. A reinforcing bar assembly is pre-assembled in which the arranged beam reinforcing bars for reinforcing bar assemblies are arranged so as to extend in directions orthogonal to each other and collectively connected at the intermediate part of the column reinforcing bars for reinforcing bar assemblies. The pre-assembled reinforcing bar assembly is set by dropping the column reinforcing bars for the reinforcing bar assembly into the precast column formwork and the beam reinforcing bars for the reinforcing bar assembly into the precast beam formwork, and Each column main reinforcement and the column main reinforcement of the column reinforcing bar for the reinforcing bar assembly are overlapped and connected by a predetermined length, and each beam intermediate main reinforcement and the beam main reinforcement of the beam reinforcing bar for the reinforcing bar assembly are connected within the precast beam formwork. A frame-shaped mold that overlaps and connects the precast column formwork to a predetermined length, arranges shear reinforcing bars in the middle of the beam, and closes the gap between the precast column formwork and the precast beam formwork between the ends of the precast beam formwork. A construction method for columns and beams in concrete structures, which is characterized by attaching a frame, pouring concrete into the columns and beams, and molding them together.