JP2578053B2 - Fixing mechanism and fixing method of steel bar in tension structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing mechanism and a fixing method for a steel rod used as an exposed tensile member in a tension structure such as a civil engineering or building structure.

[0002]

2. Description of the Related Art In conventional civil engineering and building structures, wires are generally used as exposed tensile members. But,
Since a plurality of peaks and valleys having a constant depth are spirally formed on the surface portion by twisting steel wires, the wire is not easy to finish the coating and the design is not good.

[0003] From the viewpoint of ease of painting and design,
It has been proposed to use a steel rod as an exposed tensile material instead of a wire.
The mechanism for fixing the end of the steel rod to the structure must have a function that allows the steel rod to rotate freely so that bending stress does not act.In addition, the initial tension is introduced to the steel rod as necessary. It must have a function that can do it.

However, the conventional wire fixing mechanism disclosed on page 95 of Nikkei Architecture, March 4, 1991, issued by Nikkei BP, has a support plate on the structure side in a split groove of a fork end on the wire side. The fork end is pin-joined to the support plate by a fitting and crossing pin, and the rotation direction of the fork end with respect to the structure is limited to one direction around the pin, so that the bending stress is completely applied to the steel rod. In the case of a structure that works from a direction, it cannot be diverted as a fixing mechanism for a steel bar.

[0005] Further, since this wire fixing mechanism has no function of introducing the initial tension to the steel rod at all, when it is necessary to introduce the initial tension as needed, the initial tension introducing means is separately provided to the steel rod. In this case, an unnecessary protrusion is generated in the middle of the steel bar to take up extra space, and the ease of painting and the effect of improving the design are partially reduced.

[0006]

Therefore, an object of the present invention is to provide a function of allowing the steel rod to rotate, so that the steel rod can be safely used as an exposed tensile member of a tension structure,
In addition, since it has a function of introducing an initial tension as needed, it is possible to accurately increase the strength of the structure by a prestressing action, and furthermore, since both functions are integrally realized. An object of the present invention is to provide a fixing mechanism and a fixing method for a steel rod which are compact and do not take up extra space, and are excellent in design.

[0007]

The fixing mechanism for a steel rod in a tension structure according to the present invention will now be described with reference to the accompanying drawings. A spherical or arcuate seat 3 is provided at the bottom, and a small-diameter hole 4 is provided at the center of the seat 3 on the front side of the socket 1. A steel rod inserted into the small-diameter hole 4 and the large-diameter hole 2. 5 is provided with a screw rod 6 at the end thereof, a spherical or arcuate shoulder 8 is provided on the front side of a nut 7 screwed to the screw rod 6, and screwed into a mounting hole on the side of the fixing partner 9. A screw thread 11 is provided on the outer peripheral surface of the socket 1, and the shoulder 8 of the nut 7 is brought into contact with the seat 3 of the socket 1.

[0008]

In the fixing mechanism of the steel rod, as shown in FIG. 2, the steel rod 5 is inserted from the small-diameter hole 4 of the socket 1 into the large-diameter hole 2.
A nut 7 is screwed into the screw rod 6 at the end of the steel rod 5. By moving the socket 1 along the steel bar 5, the nut 7 is accommodated in the large-diameter hole 2 of the socket 1. The socket 1 is attached to the fixing partner 9 by screwing the screw thread portion 11 on the outer peripheral surface into the mounting hole 10 on the fixing partner 9 side.

By screwing the socket 1 in a direction approaching the inner bottom surface of the mounting hole 10 and bringing the seat portion 3 of the socket 1 into contact with the shoulder portion 8 of the nut 7, as shown in FIG. Tension is established between the two fixing partners 9 and 9. When the fixing counterparts 9 and 9 are displaced by wind pressure or seismic motion, the steel rod 5 rotates within a certain range while sliding the shoulder 8 of the nut 7 against the seat 3 of the socket 1, and the steel rod 5 Has no bending stress.

When it is desired to use the steel bar 5 with an initial tension applied thereto, an appropriate external force means 13 utilizing a hydraulic jack or the like is used to fix one end of the steel bar 5 as shown in FIG. The distance between the partner 9 and the fixing partner 9 at the other end is reduced by a predetermined amount. By this shortening operation, the frame portion 14 connected to each fixing partner 9 is elastically deformed in the extension direction, and each end of the steel bar 5 and each nut 7 face the inner bottom surface of the mounting hole 10 of the fixing partner 9. Move.

While maintaining this shortened state, one or both sockets 1 are tightened in a direction approaching the inner bottom surface of the mounting hole 10, and the seat 3 of each socket 1 abuts the shoulder 8 of each nut 7. After that, when the force by the external force means 13 is removed, each fixing partner 9 attempts to return to the original position within the elastic range of the frame portion 14, and the steel rod 5 is subjected to the initial tension by the elastic restoring force. Is introduced.

In another method of introducing the initial tension, as shown in FIG. 4, a fixing partner 9 at one end of the steel bar 5 and a force point provided on the steel bar 5 close to the fixing partner 2 are provided. 12 is reduced by the external force means 13 by a predetermined amount. By this shortening operation, the steel rod 5 is elastically deformed in the elongation direction at the main portion from the force point 12 to the other end,
The one end of the steel bar 5 and the nut 7 move in the mounting hole 10 of the fixing partner 9 toward the inner bottom surface.

While maintaining this shortened state, the socket 1 at one end is tightened in a direction approaching the inner bottom surface of the mounting hole 2, and the seat 3 of the socket 1 abuts the shoulder 8 of the nut 7. After that, when the force by the external force means 13 is removed,
The main part of the steel bar 5 attempts to return to its original length within the elastic range, and this elastic restoring force introduces initial tension to the steel bar 5.

Even when the initial tension is thus introduced, when the fixing partner 9 is displaced by wind pressure or seismic motion, the steel rod 5 slides the shoulder 8 of the nut 7 against the seat 3 of the socket 1. The steel rod 5 rotates within a certain range, and no bending stress is applied to the steel rod 5.

[0015]

In the embodiment shown in FIG. 2, the nut 7 is formed in a bowl shape as a whole, and the cross-sectional diameter of the largest portion of the bowl shape is set to be equal to or slightly shorter than the large-diameter hole 2 of the socket 1.
Is rotatable in the large-diameter hole 2. The spherical seat 3 is formed over the entire length of the inner bottom portion and the side portion of the large diameter hole 2. The small diameter hole 4 of the socket 1 is formed with a tapered hole having a large diameter at the front end side. The steel rod 5 has its center on the center of curvature of the seat 3 and the outer peripheral surface of the steel rod 5 contacts the inner wall surface of the small diameter hole 4. It is rotatable within the range of contact.

The mounting hole 10 has a threaded portion formed on the inner peripheral surface of the front half portion, the socket 1 is screwed into the threaded portion, and the screwing amount is adjusted along the axial direction. The mounting hole 10 is the fixing partner 9
Instead of providing it directly on itself, a block or the like provided with the mounting hole 10 can be fixed to the fixing partner 9 by welding, bolting, or the like. If necessary, a recess 15 for fitting a rotary operation jig is provided on the front surface of the socket 1. Also, between the rear surface of the nut 7 and the inner bottom surface of the mounting hole 10,
An extra space is left to allow the movement of the steel bar 5 and the nut 7 when the initial tension is introduced.

In the embodiment shown in FIG. 5, the nut 7 is formed in a bowl shape as a whole, and the cross-sectional diameter of the largest portion of the bowl shape is set to be equal to or slightly shorter than the large diameter hole 2 of the socket 1.
The small diameter hole 4 of the socket 1 is formed to have the same diameter from the front end side to the rear end side, but the diameter of the small diameter hole 4 is set to be sufficiently larger than the diameter of the steel rod 5, and the steel rod 5 The steel rod 5 is rotatable about the center of curvature of 3 within a range in which the outer peripheral surface of the steel rod 5 abuts on the front end side edge surface of the small diameter hole 4.

In the embodiment shown in FIG. 6, the nut 7 is formed in a spherical shape as a whole, and has a sectional diameter of the large-diameter hole 2 of the socket 1.
It is set equal to or slightly shorter. The small-diameter hole 4 of the socket 1 is formed in a tapered hole having a wide diameter at the front end side.
The steel rod 5 is rotatable around the center of curvature of the seat 3 within a range in which the outer peripheral surface of the steel rod 5 abuts the inner wall surface of the small diameter hole 4.

In the embodiment shown in FIG. 7, the nut 7 is formed of a thick plate having an arcuate shoulder 8 formed on the front side, and the large-diameter hole 2 of the socket 1 correspondingly has a groove having a rectangular cross section. It is formed in a hole shape, and an arc-shaped seat portion 3 is formed in the inner bottom portion.

In the embodiment shown in FIG. 8, only the front end of the nut 7 is formed in a spherical or arcuate shape, and the side surface is formed in a plane parallel to the central axis. A fixed floating gap is set between the side surface of the nut 7 and the inner surface of the large diameter hole 2.

In the embodiment shown in FIG. 9, the nut 7 is formed in a bowl shape as a whole and has a spherical shoulder 8. Nut 7
The cross-sectional diameter of the largest portion of the bowl is set equal to or slightly shorter than the large-diameter hole 2 of the socket 1. The small diameter hole 4 of the socket 1 is formed with a tapered hole having a large diameter at the front end side. The steel rod 5 has its center on the center of curvature of the seat 3 and the outer peripheral surface of the steel rod 5 contacts the inner wall surface of the small diameter hole 4. It is rotatable within the range of contact. The socket 1 in which the screw thread portion 11 is screwed into the mounting hole 10 has a front portion protruding from the fixing partner 9. In this case, the engaging portion of the rotary operation jig of the socket 1 can be formed on the side surface of the protruding portion.

[0022]

As described above, according to the present invention, a spherical or arcuate seat 3 is provided at the inner bottom of the large-diameter hole 2 of the socket 1, and a small-diameter hole 4 is provided at the center of the seat 3. A screw rod 6 is provided on a steel rod 5 inserted into the small diameter hole 4 and the large diameter hole 2, and a spherical or arcuate shoulder 8 is provided on the front side of a nut 7 screwed to the screw rod 6. A screw thread portion 11 to be screwed into the mounting hole 10 of the mating member 9 is provided on the outer peripheral surface of the socket 1.
In which the steel bar 5 is allowed to rotate within a certain range around the seat 3 of the socket 1 so that no bending stress is applied. Thus, the steel bar 5 can be safely used as an exposed tensile member of the tension structure.

A fixing partner 9 at one end of the steel bar 5 is also provided.
The distance between the fixing member 9 at the other end and the distance between the fixing member 9 at one end of the steel bar 5 and the force point 12 of the steel bar 5 are determined by the external force means 13. With the socket 1 shortened by a predetermined amount, the socket 1 is screwed in a direction approaching the inner bottom surface of the mounting hole 10, and the seat 3 of the socket 1 is
The initial tension can be introduced into the steel rod 5 as necessary by releasing the external force by the external force means 13 at the stage of contact with the shoulder 8 of Strength enhancement can be performed accurately.

Furthermore, since the rotation permitting function of these steel bars and the function of introducing initial tension to the steel bars are integrally realized, the overall configuration can be made compact and extra space can be taken up for use. It is also excellent in design.

In this fixing mechanism, the fixing nut 7 is accommodated in the socket 1 and the socket 1 is screwed into the mounting hole 10 of the fixing partner 9. Only the steel bar 5 itself can be seen in the fixing portion, and it has an extremely neat appearance, the coating finish is further simplified, and the design is further improved.

When the seat portion 3 of the socket 1 and the projection 8 of the nut 7 are formed in a spherical shape, the steel bar 5 can rotate in all directions, and a fixing mechanism having a wide range of application can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view when a steel rod is fixed to two fixing partners by a fixing mechanism according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the fixing mechanism shown in FIG.

FIG. 3 is an explanatory diagram showing an example of an initial tension introducing method in the fixing method of the present invention.

FIG. 4 is an explanatory view showing another initial tension introducing method in the fixing method of the present invention.

FIG. 5 is a longitudinal sectional view of a fixing mechanism according to another embodiment of the present invention.

FIG. 6 is a longitudinal sectional view of a fixing mechanism according to still another embodiment of the present invention.

FIG. 7 is a longitudinal sectional view of a fixing mechanism according to another embodiment of the present invention.

FIG. 8 is a longitudinal sectional view of a fixing mechanism according to still another embodiment of the present invention.

FIG. 9 is a longitudinal sectional view of a fixing mechanism according to still another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Socket 2 Large diameter hole of socket 3 Socket seat 4 Small diameter hole of socket 5 Steel rod for exposed tensile material 6 Screw rod of steel rod 7 Nut 8 Nut shoulder 9 Fixing partner 10 Screw hole of fixing partner 11 Socket 12 threaded point 13 external force means 14 frame part 15 recess for fitting rotation jig

Claims (2)

(57) [Claims] A large-diameter hole (2) opened on the rear side of a socket (1).
A spherical or arcuate seat 3 is provided on the inner bottom of the socket 1. A small-diameter hole 4 is provided at the center of the seat 3 and opened to the front side of the socket 1. The small-diameter hole 4 is inserted through the small-diameter hole 4 and the large-diameter hole 2. A screw rod 6 is provided at an end of a steel rod 5, and a nut 7 screwed into the screw rod 6.
Is provided on the outer surface of the socket 1, and the shoulder 8 of the nut 7 is provided on the socket 1. 1. A fixing mechanism for a steel rod in a tension structure, which is brought into contact with the seat portion 3 of FIG. 2. A steel rod 5 is inserted into the small-diameter hole 4 and the large-diameter hole 2 of the socket 1, and a nut 7 screwed into a screw rod 6 at the end of the steel rod 5 is accommodated in the large-diameter hole 2. , Thread portion 11 of socket 1
Into the mounting hole 10 on the side of the fixing partner 9, and the distance between the fixing partner 9 on one end side of the steel bar 5 and the fixing partner 9 on the other end side, or one side of the steel bar 5. A direction in which the socket 1 approaches the inner bottom surface of the mounting hole 10 in a state where the distance between the fixing partner 9 on the end side and the applied point 12 of the steel bar 5 is reduced by a predetermined amount by the external applying means 13. Into the socket 1
When the spherical or arcuate seat 3 of the abutment comes into contact with the spherical or arcuate shoulder 8 of the nut 7, the external force applying means 13
A method of fixing a steel rod in a tension structure by releasing the force caused by the force.