JP2666692B2 - Vertical joint surface treatment method for reinforced concrete beams. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating a vertical joint surface at the time of rebar construction of a reinforced concrete beam.

[0002]

2. Description of the Related Art When connecting reinforced concrete beams, it is necessary to eliminate the trouble of removing the partition formwork, and to improve the integration between pre-cast concrete and post-cast concrete near the joint boundary. The main beam reinforcement is laid in the direction that penetrates the joint boundary surface. At present, the method of embedding is used in concrete.

[0003]

In the conventional construction method, a coarse mesh is used as a partition of the vertical joint surface. Therefore, it is a matter of course that the mesh of the wire mesh and the reinforcement In order to prevent concrete or cement paste from flowing out of the gap, it is necessary to reduce vibration applied to concrete. For this reason, the density of the precast concrete at the joint surface remains low, and the post-cast concrete is cast there, so that the concrete performance of the joint surface is inferior to other parts, and consequently the joint boundary. Continuity performance is poor. As a countermeasure, reinforcement is often strengthened.

[0004] In addition, the strength of the wire mesh is weak, so that the concrete often breaks due to the pressure of the concrete and the concrete flows out.

[0005]

SUMMARY OF THE INVENTION According to the present invention, the strength of the entire wire mesh is increased by reinforcing the wire mesh with a frame body combining steel rods and increasing the mesh of the wire mesh. The problem is solved at once.

That is, according to the present invention, a frame constituted by a plurality of vertical steel bars and horizontal steel bars, and having a centrally openable and closable wire mesh attached to a central vertical steel bar, is provided. A vertical joint surface treatment method for a reinforced concrete beam, characterized in that, after being inserted into all, a closed wire mesh is opened to form a vertical surface, and a wire mesh is additionally installed in a portion where the wire mesh is not installed in the vertical surface. It is.

The most important point of the present invention resides in the structure of the frame which enables the metal mesh having a dense mesh to be arranged in the form while reinforcing the mesh, and is composed of a plurality of vertical steel bars and horizontal steel bars. It is constructed, and the openable and closable wire mesh is closed and attached to the central vertical steel bar, so it can be easily inserted into the gap between the beam main bars of the existing bars, and by releasing the closed constraint after insertion It is configured to open. Various springs are adopted as such opening / closing means, and when the binding force is not applied to the spring, the wire mesh is attached to a vertical steel bar via a spring so that the wire mesh is opened, and the wire mesh is bound against the spring force. It is only necessary to cut this tie after installation.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 shows an example of a frame used in the present invention, wherein (a) is an elevation view and (b) is a plan view.

The frame 1 comprises five vertical steel bars 2 and five horizontal steel bars 3
The intersection of the vertical steel bar 2 and the horizontal steel bar 3 is spot-welded. A four-wire mesh 5 is attached to the central vertical steel bar 2 via a spring (not shown) so as to completely close the space between the horizontal steel bars 3, and a supporting steel bar 4 is attached to an end of the wire mesh 5. The wire mesh 5 is in a closed state by binding the two supporting steel rods 4 to each other.

FIGS. 2A and 2B show a state in which the frame used in the present invention is installed on a vertical joint surface of a beam formwork. FIG. 2A is a longitudinal sectional view in the longitudinal direction, and FIG. FIG. 2C is a view taken in the direction of the arrow, and FIG.

Although the upper stirrups are installed from above after the vertical joint surface treatment according to the present invention, the upper stirrups are also shown in FIG. 2 to show the structure.

In this example, six beam main reinforcements 6 are provided at the top and bottom, respectively.
Has been arranged. The frame 1 is inserted into the five gaps in the longitudinal direction of the main bar 6 along the main bar 6 from above and the vertical steel bars 2 of the frame 1 are inserted.
Are fixed to the main muscle 6. After fixing, the binding of the supporting steel bar 4 is cut to open the wire mesh 5 to form a wire mesh surface. Regarding the insertion position of the frame 1, as shown in (c), the position of the adjacent frame 1 is slightly shifted so that the support steel rod 4 at the end of the opened wire mesh 5 overlaps with the adjacent support steel rod 4. By this operation, the wire mesh 5 is installed on almost all of the vertical joint surfaces, but the uninstalled portions are left in the peripheral portions (up, down, left and right). This uninstalled portion is attached by using the vertical and horizontal joint bars 8 and the steel rods constituting the frame 1 which have been attached in the form in advance. Thus, the wire mesh is installed on the entire surface of the vertical joint, and the installed wire mesh is reinforced by the steel rod, and the concrete near the vertical joint is reinforced by the steel rod constituting the frame 1.

In FIG. 1B, the wire mesh 5 is partially shown but not entirely shown.

[0015]

As described above, the wire mesh is reinforced by the frame body in which the steel rods are combined, the mesh of the wire mesh is made dense, and the gap is almost eliminated. Even if given, the wire mesh will not be torn or the concrete or cement paste will not flow out, and the concrete performance at the joint surface is the same as the other parts, and the continuous performance is not deteriorated.

[Brief description of the drawings]

FIG. 1 shows an example of a frame used in the present invention, wherein (a) is an elevation view and (b) is a plan view.

FIGS. 2A and 2B show a state in which a frame used in the present invention is installed on a vertical joint surface of a beam formwork, and FIG.
(B) is a view on arrow AA of (a), (c) is a view of B-
FIG.

[Explanation of symbols]

1. Frame, 2 vertical bar, 3 horizontal bar, 4 supporting steel bar, 5 wire mesh, 6 main bar, 7 stirrup, 8 bar
・ Joint bars.

Claims (1)

(57) [Claims] 1. A frame composed of a plurality of vertical steel bars and horizontal steel bars, which is mounted on a central vertical steel bar with an openable and closable wire mesh closed, is inserted into all the gaps between the beam main reinforcements. Thereafter, the closed wire mesh is opened to form a vertical surface, and a wire mesh is additionally installed in a portion where the wire mesh is not installed in the vertical surface. A vertical joint surface treatment method for a reinforced concrete beam.