JPH01290838A - Joining method for column or beam of precast ferro-concrete - Google Patents

Abstract

PURPOSE:To enhance the bond strength by placing a beam, which has a bend at the exposed end of a bottom beam main strip, and another beam having a loop on a column top, engaging this bend with the loop, surrounding by an aux. band strip, and thereupon placing concrete. CONSTITUTION:Precast ferro-concrete beams 2, 2 having bend 4A, 4A at the exposed end of a bottom main strip 4 are placed on the top of a feroo-concrete column 1. Further thereon, precast ferro-concrete beams 3, 3 having loop 5A, 5A at the exposed end of another bottom beam main strip 5 are placed. Then the bends 4A, 4A are engaged with the loops 5A, 5A, and their peripheries are surrounded by an aux. band strip 6 followed by placing of concrete 7 on the top of the column 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for joining precast reinforced concrete columns and beams.

[Prior Art] Conventionally, methods for joining precast reinforced concrete columns and beams have been disclosed in Japanese Patent Application Laid-open No. 55-61832 and Japanese Patent Publication No. 82-3.
The one written and written in No. 2299 is known.

[Problems to be Solved by the Invention] The above-mentioned conventional joining method connects a precast reinforced concrete beam (hereinafter also simply referred to as a beam) mounted on the head of a precast reinforced concrete column (hereinafter also simply referred to as a column). All of the exposed ends of the main reinforcement of the lower end beam are curved, and the curved part is surrounded by reinforcing ties (Japanese Patent Application Laid-Open No. 1983-
81632), or each set of opposing curved sections were fitted with loop reinforcements, and the entire curved section was further surrounded with reinforcing straps (Japanese Patent Publication No. 82-32299).

However, according to the above method, all of the exposed ends of the main reinforcement of the lower end beam are curved, so when the curved part is surrounded by reinforcing bars, a large number of reinforcing bars become intertwined in the curved part, and the column head This has the disadvantage that the anchoring performance of the main beam reinforcement in the beam is reduced, and the strength of the beam joint is also reduced.

Furthermore, when the diameter of the main beam reinforcements increases or the number of them increases, the fixing performance further deteriorates significantly.

[Object of the Invention] Therefore, an object of the present invention is to provide a method for joining precast reinforced concrete columns and beams that can obtain high anchoring performance of beam main reinforcements at the column head, which is a beam joint part.

[Means for Solving the Problems] The present inventor has made extensive studies to achieve the above object, and as a result, has arrived at the present invention.

That is, 1. The method for joining precast reinforced concrete columns and beams according to the present invention includes: a beam having a curved portion at the exposed end of the beam main reinforcement;
A beam having a loop portion at the exposed end of the beam main reinforcement that engages with the curved portion is mounted on the column head of a reinforced concrete column, the engaged curved portion is surrounded with reinforcing bars, and the column head is covered with concrete. It is characterized by pouring.

[Example] Embodiments of the present invention will be described below with reference to the accompanying drawings.

1 and 2 show a joint between precast reinforced concrete columns and beams constructed by the method of the present invention, with FIG. 1 being a cross-sectional view and FIG. 2 being a longitudinal sectional view.

In the figure, l is a precast reinforced concrete or cast-in-place reinforced concrete column, and a precast reinforced concrete beam 2.3 is mounted on the head of the column.

When mounting /A2.3, first, the beam 2.2 having the curved portion 4A is mounted on the exposed end of the lower end beam main reinforcement 4.

Next, the beams 3, 3 having the loop portion 5A that can be engaged with the curved portion 4A are mounted on the exposed end of the lower end beam main reinforcement 5, and the curved portion 4A and the loop portion 5A are engaged as shown in the figure. . The loop portion 5A may be formed so that it can be secured to the curved portion 4A and has sufficient strength when engaged, but it is preferable that the loop portion 5A is of a closed type as in this embodiment. Preferable in terms of partial strength.

After engagement, the curved portions 4A, 4A are surrounded by reinforcing ties 6. As shown in FIG. 2, the U-reinforcing ties 6 are surrounded by
It may be surrounded in a spiral shape around the outer periphery of the curved portion 4A, but
A closed-loop muscle or the like may be inserted and surrounded.

After that, concrete 7 is poured into the head of the column 1. In Fig. 6, 8 is the column main reinforcement, and 9 is the column reinforcing strip of the column main reinforcement 8.

In addition, when using the flexible parts 2, 2 and beams 3, 3 whose upper surfaces are notched by the thickness of the slab, the above-mentioned Japanese Patent Application Laid-Open No. 55-8
As shown in No. 1Ei32 and Japanese Patent Publication No. 82-32299, the main reinforcement of the upper end beam is placed between the beams before concrete placement, and then concrete is placed on the top surface of the beam and the head of the column. The slabs are joined together.

An embodiment of the present invention has been described above, and in this embodiment, a case where four wooden beams are mounted on the head of a column 1 in a cross shape (joined to the column 1) has been explained. The present invention is not limited to this embodiment, and can be applied even when the number of beams to be mounted and the mounting positions are different from those in this embodiment.

Further, in this embodiment, the lower end beam main reinforcement is used as the beam main reinforcement having the curved portion and the loop portion, but the present invention is not limited thereto, and other beam main reinforcements (for example, the upper end beam main reinforcement) may be used.

[Effects of the Invention] According to the present invention, the number of reinforcing bars at the curved portion is smaller (half in the above example) than in the past, so even if the diameter of the main beam reinforcements becomes thicker or the number of them increases, it is easy to concrete. The effect is that the fixing performance is high and the strength of the beam joint is high.

In addition, when a beam is mounted on a column head, the beam main reinforcement having a loop part and the beam main reinforcement having a curved part are engaged, so before surrounding the curved part, the joint strength between the beams must be increased to a certain extent. As a result, the beam can be stabilized at the column head, and the strength after surrounding the curved part is extremely high.

[Brief explanation of the drawing]

1 and 2 show a joint between precast reinforced concrete columns and beams constructed by the method of the present invention, with FIG. 1 being a cross-sectional view and FIG. 2 being a longitudinal sectional view. l: Column 2.3: Beam 4: Lower end beam main reinforcement 4A: Curved section 5: Lower end beam main reinforcement 5A: Loop section 6: Reinforcement stirrup 7: Concrete 8: Column main reinforcement 9: Column reinforcement reinforcement

Claims (1)

[Claims] A beam having a curved portion at the exposed end of the beam main reinforcement, and a beam having a loop portion at the exposed end of the beam main reinforcement that engages with the curved portion are mounted on the column head of a reinforced concrete column, and the curved portion is engaged. A method for joining precast reinforced concrete columns and beams, the method comprising: surrounding the column with reinforcing bars, and pouring concrete into the column head.