JPH0446410Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to an improvement of a mortar-filled reinforcing bar joint sleeve used as a joint of reinforcing bars for reinforcing concrete in the construction of reinforced concrete structures.

(Prior technology) Mortar-filled reinforcing bar joints were developed by the Japanese Patent Publication No. 53-12732.
As disclosed in Japanese Patent Publication No. 61-57732,
This is a method in which deformed reinforcing bars are inserted into a cast iron sleeve from both sides and connected via mortar. In a tensile test of a mortar-filled joint that has developed sufficient strength, if the effective anchorage length of the reinforcing bars in the sleeve is set to 6.5 times (of the reinforcing bar diameter), the tensile strength of the joined reinforcing bar base material is 6t/ ^cm2 . In many cases, the reinforcing bar slips out of the sleeve, resulting in final failure. In this case, mortar shear failure occurred at the boundary between the tip of the reinforcing bar and the mortar. Therefore, in order to further improve the strength of the joint, it has conventionally been believed that the filling mortar must be improved or the effective length of the joint must be increased.

(Problem that the invention aims to solve) Improving mortar is not easy, and increasing the effective length of a joint makes it difficult to join concrete members, so it is necessary to improve the strength of the joint without changing the length of the joint. was required to do.

The present invention was made in response to the above-mentioned requirements, and its purpose is to
The aim is to improve the strength of the joint while keeping the length of the joint sleeve the same as before.

(Means for Solving the Problems) In order to achieve the above object, the features of the present invention are as shown in FIG.
The purpose is to increase the tensile strength of the joint by installing a cylindrical cage-like reinforcing iron wire 30 inside the joint. The reinforcing iron wire 30 is a combination of two semi-cylindrical cage-like bodies as a whole, and includes a plurality of vertical iron wires 31 extending in the axial direction of the main body 10, and an arc iron wire 32 connecting the vertical iron wires in a semicircular shape. , a shear reinforcing iron wire 3 inclined from each vertical iron wire to the axial direction at an angle of 45 degrees to 90 degrees toward the axial center.
Consists of 3. The material of the reinforcing iron wire is piano wire, which is strong and hard to bend, and the wire diameter is preferably about 1.0 to 3.2 mm. The arcuate iron wire 32 has a diameter equal to or slightly smaller than the minimum inner diameter of the main body 10 . Vertical wire 3
1 is equal to or slightly smaller than the internal length of the main body 10. It is desirable to set the length of the shear reinforcing iron wire 33 so that the tip is located at a position approximately 5 mm shorter than the valley of the reinforcing bar from the axis.

(Function) Before inserting the reinforcing bars 20 into the main body 10 of the sleeve, insert the reinforcing wires 30 of the two semi-cylindrical cage-like bodies through the reinforcing bar insertion openings 11 or 12 so as to form a cylindrical cage-like body as a whole. do. When the two reinforcing bars 20 to be joined are inserted and the mortar 40 is filled inside, the mortar 40 is reinforced by the reinforcing wire 30, so the shear fracture strength of the mortar 40 is much greater than that without the reinforcing wire. Become.

The reinforcing iron wire 30 in the shape of a semicircular cage made of piano wire with a wire diameter of 1.0 to 3.2 mm is relatively easy to roll and can be easily inserted into the main body from the reinforcing bar insertion opening.

The shear reinforcing iron wire 33 extends in the radial direction or in the main body 10.
It is tilted 45 degrees towards the center of the reinforcing bar, and the inner diameter of the envelope surface at the tip is about 10 mm smaller than the valley diameter of the reinforcing bar, so it acts effectively against tension in the axial direction of the reinforcing bar, and is reliable even if the reinforcing bar is eccentric. to strengthen the shear strength of the reinforcing bar and mortar interface.

(Example) Although the sleeve of the present invention will be explained based on the example shown in the drawings, the present invention is not limited to the example only.

As shown in FIGS. 1 and 2, the reinforcing iron wire 30 of the present invention can be applied to either a straight pipe type or a spindle type main body 10. As shown in FIG. 3, the reinforcing iron wire 30 is made up of two semi-cylindrical cage-like bodies combined into one cylindrical cage-like body as a whole, and each semi-cylindrical cage-like body is connected to the main body of the sleeve. A plurality of vertical iron wires 31 slightly shorter than the internal length of the main body 10, a plurality of semicircular arc iron wires 32 welded to the vertical iron wires, and one end welded to the vertical iron wires 31 to the center side of the main body 10. It consists of a plurality of shear reinforcing iron wires 33 that extend in the axial direction at an angle. Each iron wire is piano wire with a wire diameter of 1.0 to 3.2 mm.

When the reinforcing bar 20 is not inserted into the main body 10, the tip of the shear reinforcement wire 33 is inclined at about 45 degrees with respect to the axis, and its envelope surface is about 10 mm larger than each diameter of the reinforcing bar 20.
Since a cylindrical surface with a small outer diameter is formed around the axis, the first
As shown in the figure, even if the inserted reinforcing bar 20 is eccentric, the tip of the shear reinforcing wire 33 reaches the valley of the reinforcing bar 20. Therefore, when the mortar 40 is filled to form a joint, the shear reinforcement wire 33 is connected to the reinforcing bar 20.
Since the shear fracture strength of the mortar 40 at the boundary line along the edge of the reinforcing bar 20 is sufficiently reinforced, the strength of the joint is greatly improved.

As shown in FIG. 4, it is also possible to weld one end of the shear reinforcing iron wire 33 to the circular arc iron wire 32 instead of the vertical iron wire 31.

The reinforcing iron wire 30 is inserted into the reinforcing bar insertion opening 1 of the cast iron main body 10.
It is inserted inside from 1 or 12, but the arc iron wire 3
If you roll up 2, you can easily insert it into the main body from the reinforcing bar insertion hole.

(Effects of the invention) As mentioned above, the sleeve of the present invention has a higher mortar shear fracture strength at the interface along the reinforcing steel bar due to the reinforcing iron wire, and the effective length of the mortar and the joint body. Even if the joint strength is the same as that of conventional joints, the excellent effect of improving the strength of the joint can be obtained.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of a straight pipe type joint sleeve according to an embodiment of the present invention, Fig. 2 is a longitudinal sectional view of a spindle type joint sleeve, and Fig. 3 is a cross sectional view of the reinforcing iron wire of Fig. FIG. 4 is a diagram equivalent to FIG. 3 of another embodiment. In the figure, 10 is a main body, 11 and 12 are reinforcing bars, 20 is a reinforcing bar, 30 is a reinforcing steel wire, 31 is a vertical steel wire, 32 is an arc steel wire, and 33 is a shear reinforcing steel wire.

Claims (1)

[Claims for Utility Model Registration] 1. A sleeve comprising a tubular body whose outer diameters are the same or smaller than that of the central portion at both ends, and reinforcing bar insertion ports provided at the end faces of the both ends. , one cylindrical cage-like body formed by combining two semi-cylindrical cage-like bodies is built inside the main body,
The semi-cylindrical cage-like body includes a plurality of vertical iron wires, a plurality of circular arc iron wires connecting the vertical iron wires in a semi-cylindrical shape, and an axial center inclined from the vertical iron wire or the circular arc iron wire toward the center of the main body. A mortar-filled reinforcing steel joint sleeve containing reinforcing wire, characterized by comprising a plurality of shear reinforcing wires extending in the direction. 2. The mortar-filled reinforcing bar joint sleeve containing reinforcing iron wires according to claim 1, wherein each iron wire is a piano wire with a wire diameter of 1.0 to 3.2 mm. 3. The mortar-filled reinforcing steel joint sleeve containing reinforcing steel wire according to claim 1, wherein the diameter of the envelope surface at the tip of the shear reinforcing steel wire is approximately 10 mm smaller than the root diameter of the inserted reinforcing steel. 4. The mortar-filled reinforcing bar joint sleeve containing reinforcing iron wires according to claim 1, wherein the length of the vertical iron wire is equal to or slightly shorter than the length inside the main body.