JPH04265332A - Structure for anchoring rc beam main reinforcing bar - Google Patents

Abstract

PURPOSE:To facilitate the working efficiency of bar arrangement in a joining section and to enable beam main reinforcing bars of precast beams in a column beam joining section to have bearing force and anchoring force sufficient against concrete. CONSTITUTION:Opposed precast beams 3 are mounted on a column and beam joining section 1 on the upper part of a column 2. Beam main reinforcing bars 4 projected straight to the ends of the precast beams are fixed to the front end sections 5 of the beam main reinforcing bars using anchoring plates 7 as screw reinforcing bars in the direction of the intersection with them with nuts 6, and concrete is placed in a form of the column and beam joining section 1.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to reinforced concrete construction (
The present invention relates to an anchoring structure inside a column beam in a RC construction (RC construction), and particularly to an anchoring structure for the main reinforcement of an RC construction beam when the beam member is precast.

0002

[Prior Art] Originally, the beam main reinforcements protruding from the ends of precast beams were designed to have a sufficient anchoring length to obtain a large anchoring force (adhesion force) to the post-cast concrete within the joints of the column beams. was. For example, the main reinforcement of the RC building beam shown in FIG. By arranging the L-shaped lower end reinforcements 103 and 103' that protrude from the ends so that they overlap each other in the horizontal plane, a sufficient anchorage length can be provided for the concrete 105 that is later cast for the lower end reinforcement in the column beam joint. I'm taking it.

[0003] In addition, the RC precast beam shown in Fig. 5 has a pressure welding bump 104 at the end of the beam, and the main reinforcement of the beam is sufficiently anchored by the adhesion of the reinforcing bars and concrete at the end of the beam and the bearing force of the pressure bump portion. This is what I was trying to do.

0004

[Problem to be Solved by the Invention] However, in the structure of the RC building beam main reinforcement shown in Fig. 4, the beam main reinforcement is a modified reinforcing steel, so in order to sufficiently anchor the beam main reinforcement, it is necessary to use a 25d hook (d: different diameter). The hooks required a fixed length of 300 mm (diameter), and this hook complicated the reinforcement arrangement within the column-beam joint. In addition, in the conventional method described above, it was difficult to remove the RC formwork because the precast beam was manufactured with the main reinforcement of the beam being bent. In this case, it is possible to bend the beam main reinforcement after removing the formwork, but there is a problem that the precast beam is heavy and the bending work is difficult.

On the other hand, in the structure of the main reinforcement of the RC building beam shown in FIG. 5, pressure welding bumps are provided by pressure welding and heating, but it takes time and effort to provide a large number of pressure bumps to increase the bearing force, and the pressure bumps themselves are not very large. The problem was that it was not possible to make large ones, and therefore the bearing force could not be said to be large.

The present invention aims to solve these problems, and its purpose is to use a straight reinforcing bar as the main reinforcing bar in a precast beam, thereby eliminating the need for bending. Moreover, the present invention provides an anchoring structure for RC beam main reinforcements that has sufficient bearing force and anchoring force against concrete, even though the beam main reinforcements are relatively shorter than conventional ones.

[0007]

[Means for Solving the Problems] The present invention was completed focusing on the above object, and its gist is a fixing structure for a precast beam within a joint of a column beam, the fixing structure having The anchoring structure of the RC beam main reinforcement includes a beam main reinforcement straightly protruding from the end of a precast beam, and a fixing plate fixed in a direction intersecting the beam main reinforcement.

The fixing plate as a feature of the present invention positions a large number of beam main reinforcements protruding from the ends of the front and rear, left and right precast beams on the column, and the fixing plate is attached to at least the tip of the beam reinforcing bars. It is fixed using screws and nuts provided in the.

[0009]

[Operation] In the present invention, after removing the formwork from the main beam bar that projects straight from the end of the precast beam, a fixing plate is fixed to the straight main bar in a direction that intersects this straight main bar within the column beam joint. Therefore, even if the anchoring length of the main beam reinforcement is relatively short, the anchoring plate that intersects with it can sufficiently bear the bearing force.

Furthermore, if the fixing plate and the main reinforcing beam are fixed with nuts, bearing force can also be applied to the diameter of the nut.

[0011]

[Example] Fig. 1 is a plan view of the anchoring structure of the RC beam main reinforcement, in which the vertical beam main reinforcement and anchor plate are omitted, which is an embodiment of the present invention. FIG.

The column-beam joint 1 is a place where the upper part of the column 2 and the front, rear, left and right precast beams 3 are joined. In this case, the upper part of the pillar 1 is designed to accommodate the beam 3 directly or to be placed on capitals that extend in all directions at the upper part of the pillar.

At each end of the precast beam 3, four main beam reinforcements 4 are provided protruding from the left and right sides on the same plane, and from the top and bottom on another same plane, and the whole is screwed as the main beam reinforcement 4. The tip 5, which is made of a reinforcing bar, is fixed with a nut 6 to a square frame fixing plate 7 prepared separately. in this case,
To fix the left and right beam main reinforcements on different planes, as shown in Fig. 2, they are inserted into the right groove 9 and the left groove 9' provided at the upper ends of the left and right opposite sides of the fixing plate in opposite directions. do. In addition,
Although not shown, the upper and lower beam main reinforcements are also similar to the above.
It is disposed by fitting into the upper groove 10 and the lower groove 10'.

[0014] Reference numeral 8 denotes a column reinforcement that is erected at the top of the column.

To explain the construction method of the pillar-beam joint 1 having the above-mentioned structure, first, vertically opposing precast beams 3 are placed at predetermined positions on the upper part of the pillar 2. Next, the downwardly directed upper grooves 10 and lower grooves 10' of the rectangular frame fixing plate 7 shown in FIG. (not shown). Next, an upward left groove 9 and a right groove are provided in the rectangular frame fixing plate 7 so that the tip portions 5 of the precast beams 3 facing left and right intersect at 90 degrees above the upper and lower beam main reinforcements 4. 9'. In this way, the fixing plate 7 and the main beam reinforcement 4 are fixed together by tightening the 32 nuts 6 that are temporarily attached to the screws of the tip portion 5 in advance. Further, concrete is poured into a formwork (not shown) to join the columns 2 and beams 3 together with the slab.

FIG. 3 shows another embodiment of R
It is a longitudinal cross-sectional view of the anchoring structure of the C beam main reinforcement. In this embodiment, the vertically opposing precast beams 3A are U-shaped beams, and by first placing them vertically opposing each other on the capital 2A, the lower end reinforcements 4a as the beam main reinforcements that have been incorporated in advance as precast are removed. , and then lower reinforcements 4b and 4, which are two-stage main beam reinforcement, on different upper and lower planes.
Place the left and right precast beams 3 on which b' is precast reinforcement, and then place the lower reinforcement 4c on the inner lower end of the U-shaped precast beam 3 in the vertical direction from above.
This is the reinforcement. In this case, the fixing plate 7 is tightened by nuts 6 screwed onto the ends 5 of the threaded reinforcing bars of the lower reinforcements 4b and 4b' in the left and right direction, and is clamped and fixed between the column main reinforcements 8.

Furthermore, upper end strips 11 in the vertical and horizontal directions
In step 12, after installing the bottom reinforcement, etc., the reinforcement is freely arranged in the formwork, and then concrete is poured.

Although the beam main reinforcing bars in the above embodiments of the present invention are shown as having the same diameter φ, reinforcing bars of different diameters may be used.

[0019]

[Effects of the Invention] As described above, the anchoring structure of the main reinforcing bars for RC construction of the present invention has the main reinforcing bars protruding straight from the end of the precast beam, and the fixing plates intersecting with the main reinforcing bars. Sufficient bearing force can be obtained without increasing the anchoring length of the beam main reinforcement within the joint of the column and beam as in the past. In addition, since the beam main reinforcement is straight, the reinforcement arrangement within the column-beam joint is simpler than in conventional methods, saving on-site work, and the formwork can be easily removed during the precast beam manufacturing stage.

[Brief explanation of the drawing]

FIG. 1 is a partially omitted plan view showing the reinforcement arrangement of beam main reinforcements in an RC beam main reinforcement anchoring structure of the present invention.

FIG. 2 is a perspective view of the fixing plate 7 used in FIG. 1.

FIG. 3 is a longitudinal cross-sectional view of another embodiment from FIG. 1;

FIG. 4 is a vertical cross-sectional view showing a conventional RC beam main reinforcement anchoring structure.

FIG. 5 is a longitudinal cross-sectional view showing a conventional RC beam main reinforcement anchoring structure.

[Explanation of symbols]

1 Column beam joint 2 Pillar 3. Acupuncture 4. Beam main reinforcement 7 Fixing plate

Claims (2)

[Claims] Claim 1: An anchoring structure for a precast beam in a joint of a column beam, the anchoring structure comprising a beam main reinforcement straightly protruding from opposing ends of the precast beam, and a direction intersecting the beam main reinforcement. An anchoring structure for the main reinforcement of the RC beam, including an anchor plate fixed to the. 2. The fixing plate according to claim 1 positions and arranges a large number of beam main reinforcements protruding from the front and rear, left and right ends of the precast beam, and fixes them by screws and nuts at the tip ends. This is a main reinforcement structure for RC beams.