JP6706038B2 - Joint structure of structures - Google Patents

Description

TECHNICAL FIELD The present invention relates to a joint structure of concrete and mortar, concrete and steel, or a structure having increased shear resistance at a boundary surface between concretes.

When the structure 10 of which one is made of concrete and the structure 11 of which the other is made of concrete or mortar are simply joined by splicing as shown in FIG. 5, stress is transmitted between both structures. It is difficult, and when shear force acts during an earthquake, reciprocal displacement (deviation) occurs at the boundary surface 12 between both structures.

Therefore, conventionally, as shown in FIG. 6A, the stress transmission mechanism is configured by embedding the dowels 13 between both the structures 10 and 11 so as to be orthogonal to the boundary surface 12. In addition, instead of the dowel 13, there is also a deformed bar that is arranged orthogonally to the boundary surface (Patent Document 1).

JP, 2014-227761, A

In the conventional technique, when the dowel 13 is embedded orthogonally to the boundary surface, the relative displacement amount of the two structures 10 and 11 becomes smaller than that of the friction welding, but as shown in FIG. May cause bending deformation at the boundary surface due to shearing force, and it was not possible to reliably prevent relative displacement of the two structures 10 and 11.

On the other hand, in Patent Document 1, since a large-diameter portion made of a cylindrical steel material is provided between a pair of deformed rebars as an anchor and the large-diameter portion is embedded across the boundary surface, stress transmission is more effective than dowels. The performance can be improved. However, since the cross-sectional area of the large-diameter portion is smaller than the boundary area of the two structures, it is necessary to arrange many anchors in order to ensure stress transmission over the entire boundary surface. On the other hand, when the anchor is applied to a structure such as a wall slab or a floor slab having a relatively small thickness as compared with a column or a beam, the wall slab or the like is more likely to be attached and fractured from the large diameter portion due to shearing force.

The present invention has been made in order to solve the above-mentioned problems, and the purpose thereof is to have a structure in which shear resistance is increased as compared with arranging dowels and deformed reinforcing bars in two structures at right angles to the boundary surface. Disclosed is a body junction structure.

In order to achieve the above-mentioned object, according to the present invention, one of two structures to be joined is made of concrete or mortar, and a rib provided along the longitudinal axis between the two structures, etc. A deformed rebar having nodes provided at intervals is arranged in parallel with the boundary surface of the two structures, and shear deformation is caused by adhesion stress and bearing stress of the deformed rebar, and the other structure Is a construction material capable of fixing a cut surface of a half-divided deformed bar in which the end surface to be joined to one structure is cut in the axial direction of a steel rod for reinforced concrete, and the half surface is attached to the end surface of the other structure. A means of fixing the cut surface of the split deformed bar and embedding the half split deformed bar in the one structure was used.

According to the means, stress is transmitted between the two structures by the adhesive stress and bearing stress of the deformed reinforcing bar, and high shear resistance is exhibited at the interface between the two structures.

When the other structure is made of concrete or mortar, the deformed bars are simultaneously embedded in the other structure and the one structure with the boundary surface between the two structures as a boundary.

On the other hand, when the other structure is a steel material, the end surface that joins with one structure can be fixed by bonding or welding the cut surface of the half-divided deformed bar made by cutting the steel bar for reinforced concrete in the axial direction. In this case, the cut surface of the half-shaped deformed bar is fixed to the end face of the other structure, and the half-shaped deformed bar is embedded in the one structure. In this case, the stress transmission mechanism to one structure is constituted by the half-shaped deformed bar, and the steel material side transmits the stress by adhesive stress or welding stress.

According to the present invention, since the deformed bar is arranged between the two structures in parallel with the boundary surface, the adhesive stress and bearing stress of the deformed bar ensure the transmission of stress between the structures and prevention of relative displacement. Can be done.

Example of joining two structures to which the present invention is applied Explanatory drawing showing an example of deformed rebar Sectional drawing which shows 1st embodiment of this invention Sectional drawing which shows 2nd embodiment of this invention Explanatory drawing showing a conventional joining structure Explanatory drawing showing a conventional joining structure using dowels

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows an example of joining two structures to which the present invention is applied. (a) is a floor slab 1 and a wall slab 2, (b) wall slabs 2.2, (c) floor slab 1・It is one that is joined together. The joint structure of the present invention is configured by arranging deformed reinforcing bars 4 in parallel with the boundary surface 3 at the joints between the floor slab 1 and the wall slab 2.

As shown in FIG. 2, the deformed reinforcing bar 4 used has ribs 4a formed along the longitudinal axis on the outer periphery of a steel bar for reinforced concrete and nodes 4b formed at equal intervals. In the illustrated example, the semicircular nodes 4b are formed by shifting the upper half and the lower half by a half pitch, but the nodes may be annular ones formed at equal intervals, It may also have a spiral knot formed.

FIG. 3 shows an embodiment of the present invention, in which one structure 5 is made of concrete and the other structure 6 is also made of concrete. Then, between the two structures 5 and 6, the deformed streaks 4b shown in FIG. 2 are embedded in parallel with the boundary surface (joint surface).

According to the joint structure, when shearing forces in opposite directions are applied to the two structures 5 and 6, respectively, in the upper half and the lower half of the deformed bar 4, the adhesive stress between the joints 4b and the support of the joints 4b are supported. The pressure stress is generated in the direction opposite to the shearing force, the shearing resistance ensures the stress transmission between the structures 5 and 6, and prevents the structures 5 and 6 from being relatively displaced at the boundary surface. it can.

In addition, in FIG. 3, when one or both of the structures 5 and 6 is made of mortar, the same structure as the above-mentioned joining of concrete can be used.

FIG. 4 shows a second embodiment of the present invention, and shows a joint structure when one structure 5 is made of concrete and the other structure 7 is made of steel. In this case, the deformed bar 4 of FIG. 2 cannot be embedded in the other structure 7 made of steel. Therefore, when one of the structures is a steel material, the half-divided deformed bar 8 obtained by cutting the deformed bar 4 in FIG. 2 along the longitudinal axis is used, and the cut surface 8a of the other structure 7 made of a steel material. And the upper half having nodes 8b is embedded in one structure 5 made of concrete.

The shear resistance due to the joint structure is indicated by the adhesion stress between the nodes 8b and the bearing stress of the nodes 8b on the one structure 5 side, and by the adhesive stress of the cut surface 8a on the other structure 7 side.

The method for fixing the half-divided deformed reinforcing bar 8 to the other structure 7 is not limited to bonding, but welding may be used. Further, the other structure 7 is not limited to the steel material, and may be applied to other construction materials as long as the cut surface 8a of the half-divided deformed bar 8 can be fixed to the end surface joined to the one structure 5. it can.

The present invention can exemplify a wall slab and a floor slab as a structure, but as an applicable range, a concrete and a joint surface of concrete or mortar, an opening formed by an existing column and an existing beam is an RM unit. It can be used for joining a joint surface between the opening and the RM unit for earthquake-proof reinforcement, a joint surface between precast plates, and a joint surface where concretes that are predicted to crack are separated from each other.

1 Floor slab 2 Wall slab 3 Boundary surface 4 Deformed bar 4a Rib 4b Section 5 One structure (concrete)
6 Other structure (concrete or mortar)
7 Other structure (steel)
8 Half split deformed rebar

Claims (2)

One of the two structures to be joined is made of concrete or mortar, and between the two structures, ribs provided along the longitudinal axis and deformed rebar having nodes provided at equal intervals are provided. The structure is arranged in parallel with the boundary surface of the two structures, and has shear resistance due to the bond stress and bearing stress of the deformed reinforcing bar , and the other structure has a reinforced concrete end surface that is joined to the one structure. Made of a building material capable of fixing the cut surface of the half-divided deformed bar that is cut in the axial direction of the steel rod for use, and fixing the cut surface of the half-divided deformed rebar to the end surface of the other structure, A joint structure for a structure , wherein the half-shaped deformed bar is embedded in the one structure. Junction structure of the structure of the other structure according to claim 1, wherein comprised of steel.

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