JP3302751B2 - Brace 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 brace structure in a steel frame of various buildings.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional one-story steel frame.
A pillar 51 erected on a concrete foundation 50 and a ceiling beam 52
And a cross-shaped brace 53. The brace 53 bears only the tensile force or both the tensile force and the compressive force, and an angle material or the like is used.

[0003]

In a horizontally long steel frame as shown in the figure, a beam 5 is used due to a temperature difference between winter and summer.
In FIG. 2, large expansion and contraction occur in the longitudinal direction (direction of arrow d). The summer temperature of the beams 52 is generally 3-4 ° C. higher than the air temperature, and may be even higher depending on the usage conditions of the building. Along with this, the amount of thermal expansion and contraction also increases. On the other hand, the temperature change of the foundation 50 is relatively small, and there is resistance due to the ground.
There is almost no change in the position of the column base.

For this reason, a large interlayer displacement occurs between the beam 52 and the foundation 50 in the summer or winter, especially at the panel portions A and B at both ends of the steel frame, and a large tensile or compressive force is applied to the brace 53 due to the interlayer displacement. Occurs. When a large axial force acts on the brace 53 in this manner, the brace 53 in which a compressive force is generated may hinder the brace 53 from protruding out of the plane. Further, the stress acting on the brace 53 in this manner may cause a decrease in proof stress.

[0005] The load acting on the brace 53 can be reduced by sliding the brace 53 by making loose holes at the bolt joints at both ends of the brace 53. As described above, it is considered that a decrease in the proof stress can be relatively small if the loose holes are formed by friction bolt joining using high-strength bolts. However, if a strong bolt joint that does not cause a reduction in proof stress is used, slipping cannot be performed even as a loose hole, and the effect of reducing the axial force acting on the brace 53 may not be sufficiently obtained. Therefore, the above-mentioned protrusion cannot be prevented. For this reason, in a building having a long length, it is also often used to divide it in the longitudinal direction and join it with an expansion joint, but the structure becomes complicated and the cost increases.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a brace structure having a simple structure capable of preventing thermal stress from being released and imposing an unreasonable axial force on the brace, and preventing a reduction in proof strength of the frame. .

[0007]

Means for Solving the Problems] brace of the present invention, between the brace joint end of the brace and building structures
With a fluid pressure cylinder interposed therebetween. The bottom side cylinder chamber and the top side cylinder chamber of the fluid pressure cylinder communicate with each other through a throttle channel.

In the brace structure having this configuration, it is assumed that a pair of braces are arranged in a V-shape with each other . A fluid pressure cylinder is provided at each end of the pair of braces on the adjacent side, and a pair of inter-cylinder communication passages are provided between the fluid pressure cylinders to mutually communicate the bottom cylinder chamber and the top cylinder chamber. The between-cylinder communication passage we shall have no throttling effect.

[0009]

According to the structure of the present invention, the axial force acting on the brace due to the long-term interlayer displacement, such as when the beam thermally expands due to the temperature difference between winter and summer, is reduced by the two hydraulic cylinders. The piston expands and contracts as the sealed fluid slowly passes through the throttle channel between the cylinder chambers, releasing the axial force. With respect to a sudden load acting on the brace due to interlayer displacement due to an earthquake or the like, fluid movement between the cylinder chambers cannot follow due to the flow path resistance of the throttle flow path, and expansion and contraction of the fluid pressure cylinder does not occur. Therefore, a reduction in proof stress does not occur.

In addition to the action of the above reporting, when an abrupt change occurs, the averaging effect of the axial force generated in the two braces is obtained. That is, when interlayer displacement occurs, two V
A compressive force acts on one of the braces arranged in the shape of a letter,
A tensile force acts on the other brace. At this time, since the bottom side cylinder chamber and the top side cylinder chamber of the fluid pressure cylinder of both brace communicate with each other through a pair of communication passages between the cylinders, the bottom cylinder chamber and the top cylinder chamber communicate between the two hydraulic pressure cylinders according to the axial force acting on both brace. And the axial force is averaged. Therefore, the proof strength against earthquakes and the like is further improved.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A proposal example on which the present invention is based will be described with reference to FIG. FIG. 1A is a model diagram showing a part of a steel frame to which this brace structure is applied, as viewed from the front. The steel frame 1 is a truss structure in which a fulcrum 5 for a foundation concrete (not shown) of each column 2 and a node 6 between the beam 3 and the beam 3 are pin joints, and two braces 4 are crossed diagonally. And is connected between the node 6 and another node 7. In this embodiment, an angle material is used for each brace 4. The steel frame 1 is a long single-story building as in the example of FIG. 3, and portions similar to those illustrated in FIG. 1A are provided at a plurality of locations in the longitudinal direction.

At the lower end of each brace 4, as shown in FIG.
The tip of the piston rod 8 a of the hydraulic cylinder 8 is pin-joined to the bracket 10 of the column 2. This pin joint portion becomes the node 7. Fluid pressure cylinder 8
Is a cylinder in which oil serving as a working fluid is sealed, and a bottom cylinder chamber 11 and a top cylinder chamber 12
Are communicated with each other through a throttle channel 13 formed of a thin tube.

The operation of the above configuration will be described. For example, when the beam 3 thermally expands due to the temperature difference between winter and summer, the axial force acting on the brace 4 due to long-term interlayer displacement is as follows:
The sealed fluid slowly passes through the throttle passage 13 between the two cylinder chambers 11 and 12 of the fluid pressure cylinder 8, and the piston 8a expands and contracts. For example, when the piston rod 8a moves in the direction shown by the arrow a in FIG. 1C from the state of FIG. 1B, the sealed fluid slowly flows in the direction of the arrow b.
Therefore, the tensile or compressive axial force acting on the brace 4 is released, and the brace 4 is prevented from protruding out of the plane due to thermal stress.

When an abrupt load acts on the brace 4 due to interlayer displacement due to an earthquake or the like, the movement of the fluid between the cylinder chambers 11 and 12 cannot follow due to the flow path resistance of the throttle flow path 13 and the fluid pressure The cylinder 8 does not expand or contract. Therefore, a reduction in proof stress does not occur. For this reason, even if the steel frame 1 generates a large thermal stress due to interlayer displacement in the brace 4, it is not necessary to use an expansion joint, and the structure is simple and economical.

FIG. 2 shows an embodiment of the present invention . This example is an example of a K-shaped arrangement, that is, an example in which two braces 4 are arranged in an inverted V-shape and joined to the beam 3 at a node 14 in the middle of the pillars 2 on both sides. The lower end of the brace 4 is joined to the column 2 at a node 7. As shown in FIG. 2B, the hydraulic cylinder 8 is bolted to the upper end of each brace 4 at the bottom, and the piston rod 8a is connected to the brace connecting plate 15 of the beam 3.
It is pin-joined. This pin joint becomes the node 14 in FIG. Each of the hydraulic cylinders 8 has a bottom-side cylinder chamber 11 and a top-side cylinder chamber 12 connected to each other through a throttle channel 13 as in the above-described embodiment. Further, in this example, a pair of inter-cylinder communication passages 16 and 17 are provided between the fluid pressure cylinders 8 and 8 to mutually communicate the bottom cylinder chamber 11 and the top cylinder chamber 12. The inter-cylinder communication passages 16 and 17 do not produce a throttle effect.

According to this configuration , in addition to the action of releasing the long-term thermal stress and the action of preventing a decrease in the proof stress against a sudden interlayer displacement in the above-described proposal , the action of averaging the axial force generated in the two braces 4, 4 is achieved. can get. That is, when a sudden interlayer displacement occurs due to an earthquake or the like, a compressive force acts on one of the two braces 4 arranged in a V-shape, and a tensile force acts on the other brace 4. For example, when horizontal movement of the beam 3 in the direction of arrow F occurs, a compressive force acts on the left brace 4 in the figure, and a tensile force acts on the right brace 4. At this time, since the bottom cylinder chamber 11 and the top cylinder chamber 12 of the fluid pressure cylinders 8, 8 of the brace 4, 4 communicate with each other through a pair of communication passages 16, 17 between the brace 4, 4. The sealed fluid flows between the two hydraulic cylinders 8, 8 according to the axial force acting on the cylinder. In the horizontal movement in the direction of the arrow F, the communication passages 16 and 17 between the cylinders are provided.
Flows in the directions of arrows e and f. Therefore, the axial forces acting on the two braces 4, 4 are averaged, so that a large axial force is prevented from acting on only one of the braces 4, and the resistance to an earthquake or the like is further improved.

[0017] tail, this invention is not limited to a one-story construction steel frames, it can also be applied to the above-mentioned building 2-story.

[0018]

According to the brace structure of the present invention, a fluid pressure cylinder is interposed in the brace, and the bottom cylinder chamber and the top cylinder chamber of the fluid pressure cylinder are communicated with each other through a throttle passage. It is possible to prevent stress from being applied to the braces by releasing the stress, and it is possible to prevent a reduction in the proof strength of the frame against sudden interlayer displacement or the like at the time of an earthquake or the like. For this reason, it is not necessary to divide the building and provide an expansion joint or the like, and it is only necessary to provide a fluid pressure cylinder in a fluid-filled state on the brace, and the structure is simple and economical.

[0019] Since the fluid pressure cylinder of the two braces are connected by the communication passage between the cylinders, two stress adjacent braces which act by rapid interlayer displacement, etc. are averaged, to improve even more strength .

[Brief description of the drawings]

FIG. 1 (A) is a model diagram showing a front view of a proposal example on which the present invention is based, and FIGS. 1 (B) and 1 (C) are operation explanatory diagrams showing cross sections of the hydraulic cylinder.

FIG. 2A is a model diagram showing one embodiment of the present invention from the front, and FIG. 2B is an operation explanatory diagram showing a cross section of the hydraulic cylinder.

FIG. 3 is a model diagram of a conventional example.

[Explanation of symbols]

2 ... pillar, 3 ... beam, 4 ... brace, 8 ... fluid pressure cylinder,
11: bottom side cylinder chamber, 12: top side cylinder chamber, 13: throttle channel, 16, 17 ... communication passage between cylinders

Claims (1)

(57) [Claims] 1. A hydraulic cylinder is interposed between an end of a brace and a brace joint of a building body, and a bottom cylinder chamber and a top cylinder chamber of the hydraulic cylinder are communicated with each other through a throttle channel. Brace structure, V
Hydraulic seals on the adjacent ends of a pair of braces
Each cylinder is provided with a bottom side between both hydraulic cylinders.
One that allows the cylinder chamber and the top cylinder chamber to communicate with each other
Brace structure with a communication passage between a pair of cylinders .