JP2012246676A - Mechanical reinforcement joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanical reinforcement joint shortening an anchorage length, excellent in workability, and capable of reducing cost.SOLUTION: An inventive mechanical reinforcement joint 1 is a reinforcement joint which joins two reinforcements 5, 5 with each other at the end in an axis direction. A plurality of anchor plates 2, having a reinforcement insertion hole 4 in the center and an annular planar shape, are arranged in the center axial direction of the reinforcement insertion hole 4 at intervals. The plurality of anchor plates 2 are connected with each other by ties 3 at a plurality of positions around the reinforcement insertion hole 4. In the construction, joint connection work is completed by inserting two reinforcements 5, 5 into the reinforcement insertion hole 4 of the anchor plates of both ends. The reinforcements 5 and the mechanical reinforcement joint 1 are buried in placed concrete.

Description

  The present invention relates to a mechanical reinforcing bar joint in which two reinforcing bars are joined at an axial end in reinforcement of a reinforced concrete structure.

  At present, in the reinforcement of reinforced concrete structures such as foundations in houses, lap joints using splicing bars and binding wires are employed to connect two reinforcing bars at the axial end, without hooks. The lap joint has a long lap length in order to obtain a necessary fixing force. As one form of the lap joint, there is a pre-assembled reinforcing bar method, but there is a problem that the number of splicing bars increases because of many connecting points and the workability is poor.

  As a solution to the above-mentioned problem of the lap joint, there is a mechanical rebar joint. As a conventional mechanical reinforcing bar joint, there is a grout filling type reinforcing bar joint (for example, Patent Document 1) in which a steel pipe manufactured by casting is filled with grout and a screw type reinforcing bar joint (for example, Patent Document 2).

JP 2004-324112 A JP 2004-300366 A

  In the conventional grout-filled reinforcing bar joint, processes such as on-site grout construction and epoxy resin construction are required, and the construction period becomes longer depending on the curing period of the grout. Further, in the screw-type reinforcing bar joint, screw torque management is required as a separate process. As described above, all the conventional mechanical rebar joints require separate processes. In addition, the conventional mechanical rebar joint increases the cost because the structure of the joint body is complicated and the manufacturing requires precision.

  An object of the present invention is to provide a mechanical rebar joint that requires only a short fixing length, is excellent in workability, and can reduce costs.

  The mechanical reinforcing bar joint of the present invention is a reinforcing bar joint that joins two reinforcing bars at the axial end, and a fixing plate having a ring shape around the reinforcing bar insertion hole is formed in the central axis direction of the reinforcing bar insertion hole. A plurality of fixing plates are arranged at intervals, and the plurality of fixing plates are connected by connecting rods at a plurality of locations around the reinforcing bar insertion hole. The two reinforcing bars are respectively inserted into the reinforcing bar insertion holes of the fixing plate at both ends, and are embedded in the cast concrete together with these reinforcing bars.

According to this configuration, the bearing pressure due to the adhesive force generated on the outer peripheral surface of one reinforcing bar inserted into the reinforcing bar insertion hole of the fixing plate, particularly when the reinforcing bar is a deformed reinforcing bar, the bearing pressure generated at the nodes on the outer periphery of the reinforcing bar However, it becomes a force directed to the fixing plate through the concrete, and is transmitted to the fixing plate in which the other reinforcing bar is inserted, and is transmitted to the reinforcing bar to the other. Therefore, the transmission efficiency of the support pressure is improved, and the fixing length can be reduced. Moreover, it is only necessary to insert each of the two reinforcing bars into the reinforcing bar insertion hole of the fixing plate to a fixed position, and both the reinforcing bars can be connected without requiring separate steps such as grout injection and screw torque management. Therefore, the construction becomes easy. Construction is easier than lap joints that require binding wire construction. Construction management is also possible only by visual inspection. And since it is a simple structure only by connecting a fixing plate with a connecting rod, the manufacturing cost of a mechanical rebar joint can also be reduced.
The number of fixing plates may be only two at both ends, or may be three or more in the middle. By increasing or decreasing the number of fixing plates, it is possible to cope with various reinforcing bar strengths.

  In this invention, each said connecting rod is good also as a fan shape in which the cross-sectional shape narrows the center side of the said reinforcing bar insertion hole. By making the cross-sectional shape of the connecting rod into a fan shape, it is possible to obtain a large adhesion area of the reinforcing bar without causing the connecting rod to get in the way, and to secure a supporting pressure due to the adhesive force generated on the outer peripheral surface of the reinforcing bar. In addition, said "fan shape" is meant to include a fan shape having a circular arc shape on the outer periphery and a straight side, that is, a triangular shape.

  In this invention, the two connecting rods may be separated from each other in the diameter direction of the fixing plate. The number of connecting rods may be three or more. However, if two connecting rods are separated from each other in the diameter direction, the cross-sectional shape of the arrangement of reinforcing bars and connecting rods inserted in the fixing plate becomes flat. Therefore, even if it is a position where this mechanical rebar joint exists, a hook-like part of a shear reinforcement can be arranged if it is a position removed from a fixing board. For example, when the reinforcing bars to be connected are the main reinforcing bars of the fabric foundation, the hooks at the upper end of the shear reinforcement bars are placed along the side surfaces of the main reinforcing bars by positioning the two connecting bars of the mechanical reinforcing bar joint vertically. The bars can be arranged so as to be hung on the upper and lower connecting bars and the main bars.

  The mechanical reinforcing bar joint of the present invention is a reinforcing bar joint that joins two reinforcing bars at the axial end, and a fixing plate having a ring shape around the reinforcing bar insertion hole is formed in the central axis direction of the reinforcing bar insertion hole. A plurality of fixing plates are arranged at intervals, and these fixing plates are connected by connecting rods at a plurality of locations around the reinforcing bar insertion holes, and the two reinforcing bars are reinforcing bar insertion holes of the fixing plates at both ends. Since these are inserted into the cast concrete together with these reinforcing bars, the fixing length is short, the workability is excellent, and the cost can be reduced.

(A) is a front view of the mechanical rebar joint according to the first embodiment of the present invention, (B) is a right side view thereof, and (C) is a cross-sectional view taken along line Ic-Ic in (A). (A) is the front view which shows the joint part of the reinforcing bar which has arrange | positioned the mechanical rebar joint, (B) is the right side view, (C) is the IIc-IIc arrow sectional drawing in (A). It is sectional drawing which shows the state which has arrange | positioned the shear reinforcement in the joint part. (A) is a front view of a mechanical rebar joint according to another embodiment of the present invention, (B) is a right side view thereof, and (C) is a sectional view taken along the arrow IVc-IVc in (A). (A) is a front view of a mechanical rebar joint according to still another embodiment of the present invention, (B) is a right side view thereof, and (C) is a cross-sectional view taken along line Vc-Vc in (A).

  A first embodiment of the present invention will be described with reference to FIGS. The mechanical rebar joint 1 of this embodiment is a rebar joint that connects two rebars at the axial end in the reinforcement of a reinforced concrete structure such as the foundation of a house, as shown in a front view in FIG. The two fixing plates 2 and 2 are arranged at an interval in the facing direction so that their planes face each other, and the facing fixing plates 2 and 2 are connected by a plurality of connecting rods 3. is there. The fixing plate 2 is made of, for example, a circular steel plate, and is a plate member having a circular planar shape centered on a reinforcing bar insertion hole 4 through which a reinforcing bar is inserted. The connecting rod 3 is made of, for example, a steel rod, and is connected by welding or the like at a plurality of locations around the reinforcing bar insertion hole 4 on the plane where the fixing plates 2 and 2 face each other. By this connection, the integrated mechanical reinforcing bar joint 1 in which the plurality of fixing plates 2 and 2 and the connecting rod 3 are joined to each other is obtained.

  In this example, there are two connecting rods 3, which are respectively connected to two portions spaced in the diameter direction across the reinforcing bar insertion hole 4 in the plane of the fixing plate 2. As shown in the cross-sectional view of FIG. 1C, the connecting rod 3 has a cross-sectional shape that is a sector shape in which the center side of the reinforcing bar insertion hole 4 is narrowed. More specifically, the connecting rod 3 has a circular arc shape in cross section along the outer periphery of the fixing plate 2 and a fan shape in which both sides are connected at one point on the center side of the reinforcing bar insertion hole 4. The cross-sectional shape of the connecting rod 3 may be a fan shape in which the arc-shaped sides of the outer periphery are linear, that is, a triangular shape, and the arc-shaped sides of the outer periphery, both sides, and the arc shape of the inner periphery. It may be in the form of a fan. The sum of the cross-sectional areas of the two connecting rods 3 is equal to or greater than the cross-sectional area of the reinforcing bars to be joined, that is, the reinforcing bars inserted into the reinforcing bar insertion holes 4 of the fixing plate 2.

  FIG. 2 shows a state in which two reinforcing bars 5 serving as main reinforcing bars are joined at their axial ends in the reinforcement of a reinforced concrete structure using the mechanical rebar joint 1. Of the two reinforcing bars 5, one reinforcing bar 5 is inserted from the reinforcing bar insertion hole 4 of one fixing plate 2, and the other reinforcing bar 5 is inserted from the reinforcing bar insertion hole 4 of the other fixing plate 2. The axial ends of the rebars 5 face each other through a slight gap at an intermediate position between the two fixing plate 2 arrangement portions. The reinforcing bar 5 in this case is a deformed reinforcing bar having a rib 5a along the axial direction on the surface and a semicircular or circular node 5b along the outer peripheral surface.

  As a connecting operation of the two reinforcing bars 5, 5, it is only necessary to insert the two reinforcing bars 5 into the reinforcing bar insertion holes 4 of the fixing plate 2 of the mechanical reinforcing bar joint 1 as described above. Thereafter, the concrete is placed in the mold and hardened without filling the space of the mechanical rebar joint 1 with a dedicated filler. The space portion of the mechanical rebar joint 1 is filled with the placed concrete.

  FIG. 3 shows a cross-sectional view in which a shear reinforcement bar 6 having a U-shaped hook part 6a is engaged with the joint part of the reinforcing bar 5 of FIG.

According to the mechanical reinforcing bar joint 1 having this configuration, each of the two reinforcing bars 5 is inserted into the reinforcing bar insertion hole 4 of the fixing plate 2 and arranged at a fixed position, so that another process such as grout construction or mortar injection construction is performed. Both rebars 5 can be joined without need. Therefore, the construction is dramatically easier than the conventional mechanical reinforcing bar joint, the construction is easier than the case of the joint using the conventional accessory bar, and the construction cost can be reduced.
In the case of this mechanical rebar joint 1, the stress transmission will be described. Concrete adheres to the rebar 5 inserted through the rebar insertion hole 4 of the fixing plate 2, and the support pressure (adhesive force) generated in the concrete adhering portion causes the concrete to adhere to the concrete. Therefore, the force is directed toward the fixing plate 2. This force is transmitted from one reinforcing bar 5 to the other reinforcing bar 5 through the fixing plate 2 and the connecting rod 3. Further, the use of the fixing plate 2 improves the transmission efficiency of the support pressure (adhesive force), and the fixing length can be reduced. That is, in addition to the fixing length of the reinforcing bar 5, the concrete portion attached to the reinforcing bar 5 is resisted by the fixing plate 2, so that the fixing length can be shortened compared to the conventional mechanical reinforcing bar joint.
Since the mechanical rebar joint 1 has a simple configuration in which the fixing plate 2 is simply connected by the connecting rod 3, the manufacturing cost of the mechanical rebar joint 1 can also be reduced. Furthermore, since the quality can be confirmed visually, construction management becomes easy.

  Moreover, in this embodiment, since the cross-sectional shape of the connecting rod 3 is a fan shape in which the center side of the reinforcing bar insertion hole 4 is narrowed, the outer peripheral surface of the reinforcing bar 5 is not narrowed by the connecting rod 3. Therefore, the concrete adhesion area on the surface of the reinforcing bar 5 inserted through the reinforcing bar insertion hole 4 of the fixing plate 2 is widened, and the support pressure (adhesion force) can be increased accordingly.

  Further, in this embodiment, since the two connecting rods 3 are connected to two portions that are separated in the radial direction across the reinforcing bar insertion hole 4 in the plane of the fixing plate 2, the reinforcing bars 5 other than the fixing plate 2 are connected. The outer diameter is the same as the outer diameter. Therefore, if this mechanical rebar joint 1 is arranged in a vertical posture in which the connecting rods 3 are arranged vertically, the shear reinforcement bars 6 are matched to the outer diameter of the rebar 5 at the joint portion of the rebar 5 as shown in FIG. The U-shaped hook portions 6a can be engaged with each other.

  FIG. 4 shows another embodiment of the present invention. In this mechanical rebar joint 1, in the first embodiment shown in FIGS. 1 to 3, in addition to the fixing plates 2 at both ends, another fixing plate 2 is added at an intermediate position therebetween, so that a total of 3 A sheet of fixing plate 2 is used. The connecting rod 3 connects between the fixing plate 2 at the left end and the intermediate fixing plate 2 and between the fixing plate 2 at the right end and the fixing plate 2 at the intermediate position. Even if the connecting rod 3 is provided between the adjacent fixing plates 2 and 2, the connecting rod 3 is passed between the two fixing plates 2 and 2 at both ends, and the intermediate fixing plate 2 is connected to the connecting rod 3. The part through which 3 is inserted may be cut out. Other configurations are the same as those in the embodiment of FIGS.

  As described above, in this embodiment, when the fixing plate 2 is also arranged at an intermediate position between the left and right fixing plates 2, the compression force can be transmitted more efficiently.

  FIG. 5 shows still another embodiment of the present invention. In the mechanical reinforcing bar joint 1, in the previous embodiment shown in FIG. 4, in addition to the fixing plate 2 at the intermediate position, the fixing plate 2 at the left end and the fixing plate 2 at the intermediate position, and the fixing plate at the right end. Separate fixing plates 2 are also arranged between the fixing plate 2 and the fixing plate 2 at the intermediate position, and the fixing plates 2 adjacent to each other are connected by a connecting rod 3. Other configurations are the same as those in the embodiment of FIGS. Also in this example, the connecting rod 3 is provided between the adjacent fixing plates 2 and 2 or is passed between the two fixing plates 2 and 2 at both ends, so that it is an intermediate fixing plate. As for 2, the portion through which the connecting rod 3 is inserted may be cut out.

  As described above, in this embodiment, since the fixing plate 2 is disposed in addition to the left and right ends and the intermediate position, more efficient stress transmission is possible. Further, the reinforcing bar strength can be increased by increasing the number of fixing plates 2, and various reinforcing bar strengths can be accommodated by increasing or decreasing the number of fixing plates 2.

DESCRIPTION OF SYMBOLS 1 ... Mechanical rebar joint 2 ... Fixing plate 3 ... Connecting rod 4 ... Reinforcing bar insertion hole 5 ... Reinforcing bar

Claims (3)

A rebar joint that connects two rebars at the axial end,
A plurality of fixing plates having an annular shape around the reinforcing bar insertion hole are arranged in the central axis direction of the reinforcing bar insertion hole, and a plurality of fixing plates are arranged around the reinforcing bar insertion hole. A mechanical rebar joint in which the two rebars are respectively inserted into the rebar insertion holes of the fixing plate at both ends and embedded in the cast concrete together with these rebars.   2. The mechanical reinforcing bar joint according to claim 1, wherein each of the connecting rods has a fan shape in which a cross-sectional shape is narrower at a center side of the reinforcing bar insertion hole.   3. The mechanical reinforcing bar joint according to claim 1, wherein the connecting rods are two that are separated from each other in a diameter direction of the fixing plate.

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