JPH01127740A - Method of construction of reinforced concrete structure - Google Patents

Abstract

PURPOSE: To improve the workability by placing a concrete at other parts than an intersection of only reinforcing bars to form a cross-formed semi-PC beam in advance, inserting the intersection in a main column, and placing a concrete there. CONSTITUTION: A cross-formed semi-PC beam 10 is formed of a beam 1 and a beam 2 which are intersected in a cross-shape, an intersection part 3 is formed of only reinforcing bars, and a concrete is placed in other parts to form a concrete placement part 4. A closed stirrup 6 is arranged in the intersection part 4 with a main beam 5 as a through reinforcing bar similar to that by a main beam fixing method, hoop bars 23 are temporarily fixed 23a to the main beam of the specified number between main upper and lower end beams at the intersection part, and fitted to a main column 11 with specified intervals after insertion. The concrete placement part 4 of the beam 1 and the beam 2 are connected to each other, the main column 11 is erected on a floor part 12, a concrete 13 is placed up to a part immediately below the beams, and the part 3 without any concrete placement of only the upper part is passed. The beam arranging work can be reduced thereby.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a horizontal construction method for reinforced concrete structures.
In particular, it relates to a construction method in which only the beam is made of precast concrete at the joint between the beam and the column.

(Conventional technology) The joints between columns and beams of concrete structures, or between columns and beams and slabs, are important parts in supporting the load of the structure, and the main reinforcements, shear reinforcements, etc. of each are complicated. m entered into
It is selected.

Conventionally, this joint was constructed by placing reinforcement on-site, surrounding it with formwork, and pouring concrete into the formwork.

However, it is difficult to arrange reinforcement in complex structures such as the one described above to the exact dimensions as shown in the blueprints on site, and if the reinforcement is not arranged accurately, there is a risk of structural defects. .

In addition, it is difficult to secure the formwork accurately, and if misalignment occurs, concrete cannot be placed with high precision, which is also #i.
This was one of the causes of structural defects.

In order to solve these problems, the present inventors first formed part of the column and beam, and the part that would be the joint between them, as precast concrete members (hereinafter referred to as 10 members) in a factory, etc. Then, on the main pillar reinforcement installed at the construction site, 1
We would like to propose a construction method in which 10 members are installed 5 times by inserting them through the column main reinforcement through-holes provided in 0 members (see Japanese Patent Laid-Open No. 62'-6034).

(Problems to be Solved by the Invention) Although the construction method according to the above-mentioned earlier proposal can certainly solve the above-mentioned conventional problems, as shown in FIG. It is difficult to manufacture the through hole 102 for the main column reinforcement provided in the base 101, which serves as the main part, and it is necessary to grout the gap between the holes after the main reinforcement of the column (not shown) is penetrated.

Furthermore, it is difficult to manufacture the corner part 101' of the base 101, and it may not match the cross-sectional dimensions of the column (not shown) that exists below the PC member 100. May require finishing treatment.

Moreover, if the dimensions of this corner portion 101' are not accurate, the installation position of the column main reinforcing through hole 102 may be slightly misaligned, which may cause problems in the work of inserting the column main reinforcement.

Therefore, the present inventors considered a construction method using a so-called half-20 member in which concrete is not poured into the base 101.

Use this semi-20 member: [As a method, the conventional half-P
A known construction method is to use C-beams and pour concrete at the joints between columns and beams on site.

However, in this construction method, the main beam reinforcement at the upper end of the half-PC beam must be placed on site, which makes the on-site work complicated. In addition, the main beam reinforcement at the upper end must pass inside the stirrup (beam stirrup) embedded in the semi-PC beam, and it is difficult to arrange the reinforcement using a lifting machine such as a crane.
This makes on-site work that must rely on human power even more difficult.

The present invention was made in view of the above-mentioned problems, and its purpose is to construct half-20 members without requiring the complicated and difficult on-site work required by the conventional construction method using half-PC beams. The object of the present invention is to provide a construction method that solves various problems in the insertion work between the beam-column joint and the main reinforcement of the column, which are concerns in the construction method previously proposed by the inventors.

(Means for solving the problems) The present invention has 1. In order to achieve the above objective, only reinforcement is placed at the intersection of the beam in the beam direction and the beam in the girder direction, that is, the joint between the beam and the column, and concrete is poured in the area other than this. A cross-shaped half-PC beam is formed in advance, and the above-mentioned intersection (i.e., joint) of this half-PC beam is inserted into the column main reinforcement installed at the construction site, and then a column including this intersection (joint) is inserted. Concrete was poured in the area.

(Function) In the present invention, a cross-shaped half-PC beam is formed in advance.If this cross-shaped half-PC beam also incorporates the beam main reinforcement at the upper end, Only reinforcement will be placed at the intersections, and concrete will be placed at other parts.

The above-mentioned intersection of this half-PC beam is inserted into the column main reinforcement.

Therefore, only the reinforcing bars and no concrete are present in the insertion portion between the semi-PC beam and the main column reinforcement, and the insertion work can be performed only with a lifting machine such as a crane, without requiring any human power.

After this insertion work, concrete 1 to 1 is poured into the pillar portion including the intersection. In this way, in the column part, the beam-column joint and the column part below the joint are poured concrete, so there is no deviation in the cross-sectional shape, and even at the joint I) There is no need for grouting or finishing treatment after the insertion work, unlike in the case of the previous proposal.

Furthermore, there is no need to assemble the beam main reinforcement at the upper end later, as in the conventional semi-1) C dyeing method.

(Embodiment) FIG. 1 shows a basic example of a cross-shaped half PC wire used in the present invention, with FIG. 1(A) being a plan view and FIG. 1(B) being a side view.

In FIG. 1, the cross-shaped half-PC beam 10 is the beam 1 in the beam row direction.
and beams 2 in the girder direction intersect in a cross shape, and the intersection 3 is only reinforced, and concrete is poured in other parts to form a concrete pouring part 4.

In this basic example, the main beam reinforcements 5 of beam 1 in the beam direction and beam 2 in the girder direction are arranged in a through reinforcement arrangement similar to the beam main reinforcement fixing method used for column-beam joints in the ordinary concrete-casting method. Closed type stirrups 6 are arranged in the concrete placement part 4.

Furthermore, at the intersection 3 of the column and beam, a predetermined number of hoop reinforcements 23 are temporarily fixed 23a to the beam main reinforcement between the upper end beam main reinforcement and the lower end beam main reinforcement, and after being inserted into the column main reinforcement 11, the temporary fixings are removed and the hoop reinforcements 23 are inserted at predetermined intervals. Install.

Furthermore, the concrete placement section 4 is provided with an attachment section 7 for attaching to a hanging hook of a crane in order to lift the cruciform half-PC beam 10 with a crane during the insertion work into the main column reinforcement, which will be described later.

Furthermore, in order to ensure the rigidity of the cross-shaped semi-PC beam 10 in the horizontal plane, the concrete placement part 4 of the beam 1 in the beam direction is
and the concrete placement part 4 of the beam 2 in the girder direction are connected by a turnbuckle 8.

FIG. 2 shows a situation in which a cross-shaped semi-PC beam 10, which is not shown in FIG. 1, is inserted into a column main reinforcement 11 erected at a construction site.

That is, the column main reinforcing bars 11 are erected on the floor 12, concrete 13 is cast on site to a point just below the position where the beam is attached, and extends above the concrete casting part 13. At this extension part, there is a part 3 that is the intersection of the beam direction beam 1 and the beam direction beam 2 of the above-mentioned cruciform semi-PC beam 10, where only reinforcement is arranged and no concrete is placed.
is inserted. At this time, the cross-shaped semi-PC beam 10 is lifted by a crane (not shown) at the hanging hook attachment part 7,
It is dropped in the direction indicated by the arrow.

After the cross-shaped semi-PC beam 10 is inserted into the main column reinforcement 11 in this manner, concrete is poured into the column portion including the above-mentioned intersection (ie, column-beam joint) 3.

In addition, after this concrete reaches the specified strength, Fig. 1 <
The turnbuckle 8 shown in A> is removed.

FIG. 3 shows the first cross-shaped semi-PC beam 10 used in the present invention.
An application example is shown in which FIG. 3(A) is a plan view, FIG. 3(B) is a side view, and FIG. 3(C) is a perspective view of members used in this first application example. The same parts as in the embodiment are indicated by the same reference numerals.

In this first application example, beam 1 in the beam row direction and beam 2 in the column direction
At the center of the intersection 3 of
It is attached by welding 22 to the two inner ones 5a of a and 5b.

This cross plate 21 is for ensuring the rigidity of the intersection 3, and is used when inserting the cross-shaped semi-PC beam 10 into the column main reinforcement by lifting it with a crane as described above, and when pouring concrete after insertion. etc., has the effect of preventing excessive deformation.

Further, in this first application example, in order to increase the rigidity of the column portion including the intersection 3, a plurality of hoop muscles 23 are provided so as to surround the intersection 3.

FIG. 4 shows the second cross-shaped semi-PC beam 10 used in the present invention.
An application example is shown in which FIG. 4(A) is a plan view and FIG. 4(B) is a side view, and the same members as in the above-described embodiment and the first application example are indicated by the same reference numerals.

In this second application example, concrete is also poured into the corner part 24 of the intersection 3 of the first application example shown in FIG. It was established.

This corner portion 24 is similar to the corner portion 101' of the previous proposal by the present inventors shown in FIG.
In the case of the present invention, since the concrete pouring into the columns is carried out at the construction site after this insertion work, it is easy to match the cross-sectional shapes of the column parts, so the cross-shaped semi-PC
This is provided to ensure the rigidity of the horizontal plane of the beam 10.

FIG. 5 shows the third cross-shaped half-PC beam 10 used in the present invention.
An application example is shown in which FIG. 5(A) is a plan view, FIG. 5(B) is a side view, and FIG. 5(C) is a perspective view of members used in this third application example. The same parts as in the embodiment are indicated by the same reference numerals.

In this third application example, a mouth-shaped plate 25 is provided around the upper, middle, and lower ends of the intersection 3. The mouth-shaped plate 25 provided around the upper and lower parts has a fifth
As shown in Figure (C), beam main reinforcement penetration holes 25' are bored.

The main beam reinforcements 5 and the main beam reinforcements 5 passed through the beam main reinforcement penetration holes 25' of the upper and lower opening plates 25 and the opening plates 2
5 is fixed by a nut 26.

This mouth-shaped plate 25 is the first. Similar to the cross-shaped plate 21 in the second application example or the corner part 24 in the second application example, the rigidity of the intersection part 3 is ensured, such as when inserting into the main reinforcement of the column or when pouring concrete after the insertion work. This has the effect of preventing excessive deformation from occurring.

In addition, in the above basic example and applied example, the beam main reinforcements 5° 5a, 5
If a threaded tip is used as b (i.e., the end opposite to the intersection), the present invention can be inserted into adjacent pillars among a plurality of pillars erected on site. The connection of the beam main reinforcements of such cross-shaped semi-PC beams can be easily performed using the joint fittings.

(Effect of the invention) As explained above, according to the construction method according to the present invention,
The insertion work between the cross-shaped half-PC beam and the column main reinforcement becomes easy, and the intersection between the column main reinforcement and the cross-shaped half-C beam (i.e., the column-beam joint It is possible to improve the subsidence between the body and the body.

All of the reinforcement in the beam part was done when forming the cruciform half-PC beam (i.e., the main beam reinforcement at the top end of the half-IC beam was also done when forming the cruciform half-PC beam). ),
Reinforcement work at the construction site is reduced, making it possible to shorten the construction period.

Moreover, the horizontal construction method according to the present invention does not rely on human power to insert the cruciform semi-PC beam and the column main reinforcement, and can be performed using a lifting machine such as a crane, which is superior in terms of safety and work efficiency. It is something that

[Brief explanation of the drawing]

Figure 1 is a diagram showing a basic example of a cruciform semi-PC beam used in the present invention, where Figure 1 (A) is a plan view, Figure 1 (B) is a side view, and Figure 2 is the figure 1. Fig. 3 is a diagram showing the first application example of the cross-shaped semi-PC beam used in the present invention; Figure 3 (A> is a plan view, Figure 3 (B) is a side view, Figure 3 (C) is a perspective view of the members used in the first application example, and Figure 4 is used in the present invention. These are diagrams showing a second application example of a cross-shaped half-PC beam, in which Figure 4 (A> is a plan view, Figure 4-1) is a side view, and Figure 5 is a diagram of a cross-shaped half-PC beam used in the present invention. Third
5(A) is a plan view, and FIG. 5(B) is a diagram showing an application example.
) is a side view, FIG. 5(C) is a perspective view of the members used in the third application example, and FIG. 6 is a diagram showing 20 members of the column-beam joint according to the previous proposal by the present inventors. be. 1... Beam in the beam row direction 2... Beam in the column direction 3.
...Intersection 4...Concrete pouring section 5
．． 5a, 5b... Beam main reinforcement

Claims (3)

[Claims] (1) Only reinforcement is placed at the intersection between the beam in the beam direction and the beam in the girder direction, and concrete is poured in the area other than the intersection to form a cross-shaped semi-precast concrete beam in advance. A method for constructing a reinforced concrete structure, which comprises inserting the intersection of the semi-precast concrete beam into a column main reinforcement erected at a construction site, and then pouring concrete into the column including the intersection. (2) At the center of the intersection between the beam in the row direction and the beam in the column direction,
A construction method for a reinforced concrete structure according to claim 1, which uses a semi-precast concrete beam having cross-shaped plates that intersect in the same direction. (3) A semi-precast concrete beam having a square-shaped plate around the entire periphery of the intersection of the beam in the beam direction and the beam in the girder direction, or at least on the upper and lower peripheries of claim 1 or Construction method of reinforced concrete structure as described in paragraph 2.