JPS6251335B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a construction method for a steel reinforced concrete structure. Various construction methods have been proposed and implemented for this type of construction method.

For example, there are construction methods in which ceilings, floor slabs, beams, and columns are all reinforced on-site and constructed using cast-in-place concrete, and reinforcing materials such as stirrup bars are installed in advance in a factory as a precast structure (hereinafter referred to as a PC structure). There is a construction method in which columns and beams are embedded in concrete and joined together, and then they are joined together at the site when slab concrete is poured.

The former has the advantage that the joint strength between each part is extremely good because they are joined together with cast-in-place concrete, but on the other hand, reinforcement and concrete pouring work must be done each time on unstable scaffolding. Work efficiency is poor due to having to
There were drawbacks such as undesirable safety issues.

On the other hand, in the latter case, the PC structures placed on the upper and lower floors are simply connected together using cast-in-place slab concrete, so there is no need for reinforcing work for beam main reinforcements or stirrup reinforcements, and for placing concrete on the beams. Therefore, the work efficiency is good, but on the other hand, there is a drawback that the bonding strength between the pre-cast concrete of the PC structure and the slab concrete poured on site is weak.

Therefore, in order to compensate for the drawbacks of each of the above construction methods, the present invention has been developed by attaching at least a part of the beam stirrup bars in advance by burying the base in a precast concrete wall (hereinafter referred to as a PC wall), so that it can be easily installed at the construction site. To provide a construction method that facilitates reinforcing work and enables strong integral connection between each PC wall and between each PC wall and slab beam by pouring beam concrete on-site at the same time as slab concrete pouring. It is a thing.

An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 are a side view and a front view of a PC structure A that has been preassembled at a factory. This PC
Structure A consists of a PC wall 1, a beam steel frame 2 made of H steel protruding from the upper end of the PC wall, a stirrup reinforcement 3 whose base is installed inside the PC wall, and a lower bent inner surface of the stirrup reinforcement. It consists of a joined lower beam main reinforcement 4 and a joining reinforcement 5 protruding from the lower end of the PC wall.

PC wall 1 has cross-shaped braces 1a as required.
The anchor rods 2a welded to the lower surface of the beam steel frame 2 and the bases of the joining reinforcing bars 5 were buried, respectively. Concrete is poured in the same condition. In addition, as a method for installing the base side of the stirrup reinforcement 3 in the PC wall, it is possible to arrange the reinforcement in advance before concrete is poured, or to bury a cutting die in advance and remove the cutting die after the concrete has hardened and insert the through hole. It is also possible to insert the Starrup muscle into the muscle. In addition, each stirrup reinforcement 3 is arranged at a predetermined interval so as to surround the lower beam main reinforcements 4, 4, and the end of each stirrup reinforcement is connected to the beam main reinforcement on either side, and is connected to each beam main reinforcement. Join by welding or bundled wire. Note that instead of the joining reinforcing bars 5, a steel rod or a long iron plate may be used as the joining member. Next, FIG. 3 shows a PC structure B according to another embodiment.
FIG.

All of the PC structures indicated by the same reference numerals have the same structure as the PC structure A shown in FIGS. 1 and 2, but the stirrup muscle is divided into a base side 6 and an upper side 7. be. That is, the proximal side 6 is PC like the stirrup muscle 3 in the above embodiment.
The upper stirrup reinforcements are installed adjacent to these base stirrup reinforcements 6 and attached to the lower beam main reinforcements 4, 4, either by burying them before concrete pouring of the wall 1 or by inserting them into the through holes from which the cutting mold has been removed. Both lower ends of the striations 7 are connected. This structure has the advantage that the stirrup muscles can be easily processed and attached. The PC structure A or B, which has been preassembled in the factory in this manner, is brought to the construction site and is constructed integrally with cast-in-place concrete, as shown in FIG.

That is, two PC structures are prepared, and the PC structures A ₂ and A ₁ are placed above and below the construction position of the slab 11, which is the ceiling of the lower floor and the floor of the upper floor, and the slab 11 and the beam 12 are placed in between. Formwork 13 is installed at the bottom of the construction area.
At the same time, the _upper beam main reinforcements 14, 15,
16 is inserted through the bar, and the reinforcement is arranged by welding or joining with wire bundles. Although not shown in this case, slab 1
Needless to say, the necessary reinforcing bars are placed on the first side as well.

Concrete was then placed in the construction area divided by the formwork 13, and the slab 11 and beam 12 were constructed, and concrete was buried between the PC walls 1 and 1 of each PC structure A ₁ and A ₂ . They are joined together via beam steel frame 2 and joining reinforcing bars 5.

In the above example, the stirrup bars 3, 6, 7 and the lower side beam main bars 4 were assembled in advance at the factory, but unless they are buried in the PC wall 1 in advance, they are not installed in the construction area. It can also be assembled on-site.

In this way, the construction method according to the above embodiment is
Wall prefabricated with precast concrete 1
and upper side beam main reinforcements 14, 15, which are beam members attached to the wall and whose passage may be obstructed by at least unillustrated reinforcing bars arranged within the slab 11.
Since the lower side beam main reinforcements 4, 4 and the stirrup reinforcements 3, 6, 7, excluding 16, can be assembled in advance at a factory or on-site outside the construction area, it is possible to ensure safety and improve work efficiency. In addition, by pouring beam concrete at the same time as the slab concrete poured in-situ and interconnecting the walls on the upper and lower floors, the concrete cast for the slab 11, beam 12, walls A ₁ and A ₂ , and the beam It is possible to firmly integrate the steel frame 2, the connecting reinforcing bars 5, the stirrup bars 3, and each beam main bar.

Next, FIG. 5 shows a PC structure according to another embodiment,
This figure shows the construction method for this structure. These PC structures C ₁ and C ₂ are connected to the PC wall 1 as in the previous embodiment.
The stirrup reinforcement 8 whose base end penetrates the PC wall 1 is connected to the lower side beam main reinforcements 9, 9 and the upper side beam main reinforcement 1.
0 and 10, and is bent inward from both sides of the beam steel frame 2. This PC structure is not hindered by the upper side beam main reinforcements 10, 10 because they do not protrude to the reinforcing bars (not shown) in the slab 11, and therefore, all of them are installed in the factory or in the slab construction area. Work efficiency is extremely high because they can be pre-assembled on site.After assembly, the slab 10 and beams 12 are constructed using concrete placed in the formwork 13 in the same way as in the previous embodiment, and each of the upper and lower floors is This is to join the walls 1, 1 together.

The work efficiency of this embodiment is much higher than that of the previous embodiment, and the joint strength between the slab and the walls of the upper and lower floors is improved compared to the conventional PC structure in which the walls and beams are integrated. However, compared to the example described above, the bonding strength is inferior to the extent that the PC structure does not protrude toward the slab 11 side.

As described above, in the construction method of the present invention, a precast concrete wall to which steel beams and joint members are attached is manufactured in advance in a factory, and stirrup reinforcement is attached to the precast concrete wall with its base penetrating. By assembling at least the main reinforcement of the lower side beam connected to this stirrup reinforcement in advance at a factory or a processing plant near the site where work can be done safely to create a precast structure, scaffolding is built and everything is assembled within the construction area. It is possible to ensure work safety and improve work efficiency compared to other methods.

In addition, the two precast structures mentioned above were installed in the designated construction area so that the walls of the upper and lower floors were formed by sandwiching the slab, and after completing the reinforcement work such as the remaining upper side beam main reinforcements, the slab construction area was installed. By simultaneously pouring concrete into the formwork attached to the beam construction area, the beam and slab are constructed, and these precast walls are integrally joined. Because both the concrete beam and the slab are constructed at the same time using cast-in-place concrete, there is a significant difference in the strength of the joint through the concrete compared to the conventional construction method that combines a PC beam and a cast-in-place concrete slab. Furthermore, these slabs and beams and each precast wall are firmly connected through the poured concrete, the steel beam materials, joint members, and stirrup reinforcements attached to the walls embedded in this concrete. be able to.

[Brief explanation of the drawing]

The drawings all show embodiments of the present application; FIG. 1 is a side view of a precast structure, FIG. 2 is a front view of the same, FIG. 3 is a side view of a precast structure according to another embodiment, and FIG. 4 is a side view of the precast structure. FIG. 5 is an explanatory diagram of a construction mode according to another embodiment. Explanation of symbols, 1... Precast wall, 2... Reinforced beam, 3, 6, 7, 8... Stirrup reinforcement, 4, 9,
10, 14, 15, 16... Beam main reinforcement, 5... Connection reinforcing bar, 11... Slab, 12... Beam, 13... Formwork, A,
A ₁ , A ₂ , B, C, C ₂ ... precast structure.

Claims (1)

[Claims] 1. Attach stirrup reinforcements to the precast concrete wall in such a manner as to penetrate through the base of the precast concrete wall, each with a steel beam material attached to the upper end and a joint member made of steel frames or reinforcing bars at the lower end, and attach at least the lower side beam main reinforcement to the stirrup reinforcements. The precast structures are assembled in advance before construction, and the two precast structures are installed one above the other in the construction area to complete the remaining reinforcement work, and then the slab concrete is placed in the attached formwork. A construction method for a steel-framed reinforced concrete structure, characterized in that a slab and a beam are constructed by simultaneously pouring beam concrete on-site, and these and each precast structure are integrally connected to each other.