JP2002309670A - Composite damping brace - Google Patents

Abstract

(57) [Problem] To provide a composite vibration damping brace which has excellent buckling strength and can reduce various vibrations from small amplitude to large amplitude generated in a structure despite its simple and lightweight structure. provide. A shaft member (1) made of a flat steel material or a cross-shaped steel material whose both ends (1a, 1b) are connected to a frame of a structure.
An elastic portion 2 having a large shaft area and a yielding portion 3 having a small shaft area are formed, and a steel pipe member 6 having a surface opposed to the surface is disposed on the surface of the shaft member 1 so as to be relatively displaceable. In the composite vibration damping brace in which the steel pipe members 6 are connected to each other, a viscoelastic body 7 is interposed between the shaft member and the steel pipe member in the elastic portion 2 and the shaft member 1 is expanded and contracted. A discontinuous portion having a gap 5 capable of absorbing the water is provided, and the viscoelastic body 7 is separated from the discontinuous portion.
The steel pipe member 6 was fixed to the shaft member 1 on the side where is not interposed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite vibration damping brace that reinforces a framework such as a steel frame structure, and at the same time, can reduce various vibrations from small amplitude to large amplitude generated in a structure. Things.

[0002]

2. Description of the Related Art In recent years, in order to improve the livability of various structures and to ensure safety in the event of an earthquake, in addition to securing the seismic safety of the frame itself composed of columns and beams, the framework itself has been required. Various vibration damping structures have been developed to reduce the shaking of structures caused by earthquakes, strong winds, and the like by adding special devices and parts to the inside.

As one type of such a vibration damping structure, a viscoelastic damper that absorbs energy by shearing deformation of a viscoelastic body or a hysteretic damper that utilizes the energy absorbing ability by plastic deformation of a metal material is provided in the above-mentioned frame. Incorporating structures are known.

[0004]

According to the viscoelastic damper, since the viscoelastic body has excellent responsiveness to small deformation, small vibrations generated in the structure due to strong wind or the like are reduced. There is an advantage that the property can be further improved. However, like during a major earthquake,
When a large speed or large deformation is applied, an excessive shearing force is generated, and the reaction force is transmitted to the above-mentioned frame side to cause the destruction of the frame, and also break due to the excessive deformation and lose the function as a damper. There was a problem that there was a possibility of being performed. In addition, the viscoelastic body has a problem that the damping performance varies due to the temperature dependency,
In particular, at a low temperature, the above-described problem of causing a destruction of the skeleton due to exerting a large damping force becomes remarkable.

On the other hand, in a hysteretic damper, energy can be effectively absorbed by a hysteresis damping of a member during a large earthquake and the vibration can be reduced, but on the contrary, a small vibration caused by a strong wind or the like can be achieved. However, there was a problem in that it was not possible to function effectively, and therefore it was not possible to expect an effect of improving livability.

Accordingly, as disclosed in Japanese Patent Application Laid-Open No. 11-153194, a vibration damping brace combining these viscoelastic dampers and hysteretic dampers has been proposed.
In this vibration damping brace, steel buckling prevention members are alternately disposed on both sides of a steel central axial force member serving as a hysteresis damper from one end and the other end in a laminated manner, and a viscous force is applied between these members. The viscoelastic damper is made to function as a viscoelastic damper by filling an attenuating material using an elastic body, that is, a viscoelastic damper and a hysteretic damper are connected in parallel.

However, in the above-mentioned conventional vibration damping brace, since the steel central buckling member is formed by laminating two or three layers of steel buckling prevention members on both sides, the structure is complicated. There are disadvantages in that the weight is increased and the cost is disadvantageous. Also, as a result of connecting the viscoelastic damper and the hysteretic damper in parallel, it is difficult to obtain a damping property for a small swing, and effectively suppresses a wide range of swing from a small amplitude to a large amplitude. There is also a problem that it is difficult.

The present invention has been made in view of the above circumstances, and a composite vibration damping brace capable of reducing various vibrations from small amplitude to large amplitude generated in a structure despite its simple and lightweight structure. The purpose is to provide.

[0009]

According to a first aspect of the present invention, there is provided a composite vibration damping brace according to the present invention, wherein a shaft member made of a flat steel material or a cross-shaped steel material having both ends connected to a frame of a structure is provided with a shaft. An elastic portion having a large area and a yielding portion having a small shaft area are formed, and a steel pipe member having a surface opposed to the surface is disposed on the surface of the shaft member so as to be relatively displaceable, and these steel pipe members are connected to each other. In the combined vibration damping brace, a viscoelastic body is interposed between the shaft member and the steel pipe member in the elastic portion, and a gap is formed in the shaft member to absorb expansion and contraction of the composite vibration damping brace. A discontinuous portion is provided, and the steel pipe member is fixed to the shaft member on the side of the discontinuous portion where the viscoelastic body is not interposed.

[0010] The invention described in claim 2 is the same as the claim 1.
The invention according to the above, characterized in that an engaging portion for preventing a relative displacement of not less than a predetermined value is formed between the other of the shaft member bordering the discontinuous portion and the steel pipe member. is there.

According to a third aspect of the present invention, there is provided a composite vibration damping brace according to the present invention, wherein a shaft member made of a flat steel material or a cross-shaped steel material whose both ends are connected to a frame of a structure has an elasticity with a large shaft area. Forming a part and a yielding part with a small axial area,
On a surface of the shaft member, a steel pipe member having a surface opposed to the surface is disposed so as to be relatively displaceable, and in a composite vibration damping brace in which these steel pipe members are connected to each other, the shaft member and the steel pipe member in the elastic portion are provided. And a discontinuous portion in which a gap capable of absorbing the expansion and contraction of the composite vibration damping brace is provided in the elastic portion of the shaft member. It is.

Here, the elastic portion of the shaft member is preferably set to have a shaft area that follows mainly by elastic deformation even in an assumed large earthquake, and the yield portion is preferably set when excessive deformation occurs. In addition, it is preferable to set the shaft area to reach the yield point before the viscoelastic body breaks and undergo plastic deformation.

Preferably, the viscoelastic body is made of a polymer material such as an acrylic, silicon, diene, or asphalt-based material, and is interposed between a shaft member and a steel pipe member. As a method, a method of previously bonding to the surface of the shaft member at the time of assembling, a method of disposing a steel pipe member along the shaft member, and then filling the space between the two can be applied. Further, as the steel pipe member, it is preferable to use a rectangular steel pipe having a cross-sectional shape that is general-purpose and can effectively exhibit a buckling prevention function.

According to the composite vibration damping brace of any one of claims 1 to 3, an elastic portion and a yield portion are formed on the shaft member, and the viscoelastic body is provided between the shaft member and the steel pipe member in the elastic portion. And the shaft member is provided with a discontinuous portion having a gap, so that the viscoelastic damper using the viscoelastic body and the hysteretic damper played by the yielding portion of the shaft member are arranged in series. It has a configuration. As a result, in the case where a small amplitude tremor caused by a strong wind or the like occurs in the structure, first, the viscoelastic body interposed between the shaft member and the steel pipe member is absorbed by the shear deformation. Can be.

At this time, as shown in FIG.
Is the shear area S between the shaft member B and the steel pipe member C.
It is known that it is proportional to the ratio (S / d: shape factor) of the shear thickness d. Therefore, if the shear thickness d is reduced, a large damping force can be obtained even with the same shear area S. In other words, even with a small shear area S,
An equivalent damping effect can be obtained. However, when the shear thickness d is reduced as described above, there is a problem that allowable shear strain of the viscoelastic body, that is, allowable axial deformation is reduced.

In this respect, in the present invention, since the viscoelastic damper and the hysteretic damper are arranged in series as described above, the amplitude of the vibration acting on the structure due to the occurrence of a large earthquake is large. In this case, the yielding portion of the shaft member yields in the process of increasing the shear deformation of the viscoelastic body, and the axial deformation of the entire brace mainly shifts to the deformation at the yielding portion. Can be suppressed from being sheared. Moreover, as a result of the viscoelastic body not having excessive damping force, there is no possibility of adversely affecting the frame,
In addition, the cooperation between the viscoelastic damper and the hysteretic damper can prevent peeling or breakage due to excessive deformation of the viscoelastic body, and can also absorb fluctuations in the damping effect due to temperature dependence of the viscoelastic body. .

As described above, according to the composite vibration damping brace according to the present invention, the viscoelastic damper formed of the viscoelastic body interposed between the elastic portion and the steel pipe member functions for small-amplitude vibration. With respect to large-amplitude sway, the hysteretic damper in the yielding portion can effectively absorb energy and reduce the energy. Various vibrations from a small amplitude to a large amplitude can be reduced.

In addition, when the composite vibration damping brace receives a compressive force due to large shaking, the steel pipe member provided along the yielding portion suppresses the deformation of the shaft member out of the plane. Buckling of the shaft member is prevented. As a result, the buckling strength of the entire brace can be increased.

By the way, the deformation due to the yielding portion when a large amplitude swing acts on the structure, and the effect of suppressing the shear deformation of the viscoelastic body due to this, are based on the specifications such as the viscosity and shear thickness of the viscoelastic body. It can be adjusted by appropriately setting specifications such as the rigidity of the shaft member, but if excessive shear deformation is applied to the viscoelastic body, the viscoelastic body breaks, and the function as a damper is lost. There is a fear. Therefore,
According to the second aspect of the present invention, if an engaging portion for preventing a relative displacement equal to or more than a predetermined value is formed between the other of the shaft members and the steel pipe member bordering on the discontinuous portion, the viscoelastic body is formed. Peeling or breakage due to excessive deformation can be reliably prevented.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) FIGS.
1 shows a first embodiment of a composite vibration damping brace of the present invention. 1 and 2, reference numeral 1 denotes both ends 1
Reference numerals a and 1b denote shaft members made of a cross-shaped steel material connected to the framework of the structure. An elastic portion 2 having a large shaft area is formed on the end 1a side of the shaft member 1. A yielding portion 3 having a smaller axial area than the elastic portion 2 is formed between the elastic portion 2 and the end portion 1b via an inclined transition portion 4. A gap 5 is formed between the end portion 1a and the elastic portion 2 so as to absorb the expansion and contraction of the shaft member 1 and the expansion and contraction of the entire composite vibration damping brace caused by the shear deformation of the viscoelastic body 7 described later. A discontinuous portion is formed.

At each of the four corners of the shaft member 1 formed of a cross-shaped steel material, square steel pipes (steel pipe members) 6 are disposed between both ends 1a and 1b so as to be relatively displaceable. The steel pipes 6 are integrally connected by a flat bar 9 joined along adjacent portions. Further, a viscoelastic body 7 bonded to both the elastic portion 2 and the square steel tube 6 is interposed between the square steel tube 6 and the elastic portion 2 of the shaft member 1. Further, a bolt insertion hole 8 is formed at the end 1a of the shaft member 1, and a bolt insertion hole (not shown) is formed at an end of the square steel pipe 6 facing the bolt insertion hole 8, respectively. I have. The rectangular steel pipe 6 is fixed to the shaft member 1 at the end by tightening the high-strength bolts 6a inserted into the two insertion holes 8.

Here, the elastic portion 2 of the shaft member 1 is
Even in the case of a supposed large earthquake, the axial area is set to follow mainly by elastic deformation, while the yield portion 3 reaches the yield point before the viscoelastic body 7 breaks when excessive deformation occurs. The shaft area is set to the plastic deformation. Further, as the viscoelastic body 7, a polymer material such as acrylic, silicon, diene, and asphalt is used.

In order to assemble such a composite vibration damping brace, first, as shown in FIG. 1 (a), a viscoelastic body 7 is adhered to the surface of the elastic portion 2 of the shaft member 1, and then, as shown in FIG.
As shown in FIG. 1B, the viscoelastic body 7 is also adhered to the square steel pipe 6 by arranging the square steel pipes 6 at the four corners of the shaft member 1 respectively. As shown, a high-strength bolt 6a is inserted into a square steel pipe 6 and a bolt insertion hole 8 formed in an end 1a of the shaft member 1, and tightened.
Flat bar 9 provided adjacent to the adjacent square steel pipe 6
Are welded to the square steel pipes 6 to integrally connect the square steel pipes 6. Thus, the assembly of the composite vibration damping brace is completed.

According to the composite vibration damping brace having the above structure, as shown in FIGS. 3A and 3B, the elastic member 2 and the yielding member 3 are formed on the shaft member 1, and Since the viscoelastic body 7 is interposed between the shaft member 1 and the square steel pipe 6 and the discontinuous portion having the gap 5 is provided in the shaft member 1, a viscoelastic damper using the viscoelastic body 7 is provided. The hysteresis damper which the yielding portion 3 of the shaft member plays is arranged in series.

As a result, when a small vibration of the amplitude due to a strong wind or the like is generated in the structure, and a compressive force and a tensile force act on the composite vibration damping brace, first, one end 1a of the shaft member 1 is applied to the structure. Relative displacement occurs between the fixed rectangular steel pipe 6 and the yielding portion 3 and the elastic portion 2 from the other end 1 b of the shaft member 1, and a viscoelastic body 7 between the elastic portion 2 and the rectangular steel pipe 6. Is sheared. Thereby, the energy of the shaking can be absorbed, the shaking can be reduced, and the livability can be improved. Incidentally, the transmission of the axial force in the composite vibration damping brace at this time is performed by one end 1a of the shaft member 1 → high-strength bolt 6a → square steel pipe 6 → viscoelastic body 7 → elastic portion 2 of the shaft member 1 → yield portion 3 → It becomes the other end 1b of the shaft member 1.

Next, when the amplitude of the shaking acting on the structure increases due to the occurrence of the large earthquake, the yielding portion 3 of the shaft member 1 is reduced while the shear deformation of the viscoelastic body 7 increases. Yields and reduces the sway by its hysteretic damping. At this time, the axial deformation of the entire brace is mainly at the yielding portion 3, so that the shear deformation of the viscoelastic body 7 can be suppressed, and the viscoelastic body 7 does not have excessive damping force. There is no risk of adversely affecting Further, the cooperation between the viscoelastic damper by the viscoelastic body 7 and the hysteretic damper by the yielding portion 3 allows the viscoelastic body 7
Can be prevented from peeling or breaking due to excessive deformation of the viscoelastic body 7, and the fluctuation of the damping effect due to the temperature dependence of the viscoelastic body 7 can be absorbed.

As described above, according to the above-described composite vibration damping brace, the elastic portion 2 and the square steel pipe 6 can be prevented from swinging with a small amplitude.
A viscoelastic damper with a viscoelastic body 7 interposed between the damper and the oscillating body functions to effectively absorb energy by a hysteretic damper in the yielding portion 3 to reduce large-amplitude sway. Therefore, despite the simple and lightweight structure, various vibrations from small amplitude to large amplitude generated in the structure can be reduced.

In addition, when the composite damping brace is subjected to a compressive force due to large shaking, the square steel pipe 6 provided along the yielding portion 3 and connected and integrated with each other by the flat bar 9. Since the out-of-plane deformation of the shaft member 1 is suppressed, buckling of the shaft member 1 can be prevented, and as a result, the buckling strength of the entire brace can be increased.

(Embodiments 2 to 4) Next, FIG.
(C) show the second to fourth embodiments of the present invention, respectively, and the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals and the description thereof will be simplified. FIG.
In the composite vibration damping brace according to the second embodiment shown in (a), the shaft member 1 is cut between the elastic portion 2 and the transition portion 4 to expand and contract the shaft member 1 and shear deformation of the viscoelastic body 7. 1 that can absorb the expansion and contraction of the compound damping brace generated by
A viscoelastic body 7 is similarly adhered to the surface of the elastic portion 2 shown by hatching in the figure and the surface of the square steel pipe 6 (not shown). And
The square steel pipe 6 (not shown) is tightened by a high-strength bolt inserted between the steel pipe 6 and a bolt insertion hole 8 formed on the transition portion 4 side, so that the shaft member 1 bordering the discontinuous portion is formed.
Is fixed on the upper side.

Further, in the composite vibration damping brace according to the third embodiment shown in FIG. 4B, an elastic portion 2 is formed at the center of a shaft member 1, and the elastic portion 2 and both end portions 1a and 1b are connected. In between, the yielding portion 3 is formed via the transition portion 4, and the shaft member 1 is cut at the center of the elastic portion 2 so that the expansion and contraction of the shaft member 1 and the shear deformation of the viscoelastic body 7 can be absorbed. A discontinuous portion having a large gap 11 is formed. Then, in this composite vibration damping brace, the square steel pipe 6 (not shown) is not fixed to the shaft member 1 by the above-mentioned high-strength bolts or the like, and both ends 1 of the shaft member 1 are not fixed.
a, a viscoelastic body bonded between the rectangular steel pipe 6 and the elastic part 2 of the shaft member 1 and bonded to both the elastic part 2 and the square steel pipe 6. 7 are interposed.

Further, in the composite vibration damping brace according to the fourth embodiment shown in FIG. 4C, an elastic portion 2 is formed at the center of the shaft member 1 similarly to the one shown in FIG. A yielding portion 3 is formed between the elastic portion 2 and both ends 1a and 1b via a transition portion 4, respectively, and is cut between the elastic portion 2 and the transition portion 4 to expand and contract the shaft member 1. A discontinuous portion having a gap 12 capable of absorbing the shear deformation of the viscoelastic body 7 is formed. The rectangular steel pipe 6 (not shown) is fixed to the upper side of the shaft member 1 at the discontinuous portion by a high-strength bolt inserted between the rectangular steel pipe 6 and a bolt insertion hole 8 formed on the transition portion 4 side. Have been. In the second to fourth embodiments, the configurations of the square steel pipes 6 not shown and the flat bars 9 connecting them are the same as those shown in FIG.

The same operational effects as those shown in FIG. 1 can be obtained by the composite vibration damping braces shown in FIGS. 4 (a), 4 (b) and 4 (c). By the way, the transmission of the axial force in the composite vibration damping brace shown in FIG. 4 (a) is performed by one end 1a of the shaft member 1, the elastic portion 2 of the shaft member 1, the viscoelastic body 7, the square steel pipe 6, and the high-strength bolt 6a. → the yield portion 3 → the other end 1 b of the shaft member 1.

In the composite vibration damping braces shown in FIG. 4B, the end 1a of the shaft member → the yield portion 3 → the lower portion of the elastic portion 2 → viscoelastic body 7 → square steel pipe 6 → viscoelasticity. The body 7 → the upper part of the elastic part 2 → the yield part 3 → the other end 1 b of the shaft member 1. Further, in the composite vibration damping brace shown in FIG. 4C, one end 1a of the shaft member 1 → the yield portion 3 → the elastic portion 2
→ viscoelastic body 7 → square steel pipe 6 →→ high strength bolt 6a → yield part 3 → other end 1b of shaft member 1.

(Embodiment 5) FIG. 5 shows a fifth embodiment of the present invention. Similarly, the same components as those shown in FIG. 1 are denoted by the same reference numerals. . In this composite vibration damping brace, as shown in FIG.
The square steel pipe 6 is connected to the end 1
A flat projection 20 projecting from the surface is joined to the other end of the shaft member 1 that is fixed to the a side and borders the discontinuous portion. On the other hand, the square steel pipe 6 facing the convex portion 20
Is formed with a concave portion 21 formed by cutting out a predetermined length dimension in the longitudinal direction. The square steel pipes 6 are arranged at the four corners of the shaft member 1 in a state where the protrusions 20 are engaged with the respective recesses 21. The other configuration is the same as that shown in FIG.

According to the composite vibration damping brace according to this embodiment, the same operation and effect as those shown in FIGS. 1 to 4 can be obtained, and further, the shaft member 1 and the square steel pipe 6 which are relatively displaced can be connected. A concave and convex portion (engaging portion) for preventing a relative displacement of a predetermined value or more.
Since the viscoelastic body 7 is subjected to excessive shearing deformation in the event of a large earthquake, the projections 20 are locked to the ends in the recesses 21, so that the viscoelastic body 7 is not damaged. Relative displacement is prevented. As a result, peeling or breakage due to excessive deformation of the viscoelastic body 7 can be reliably prevented.

In the above embodiment, only the case where the shaft member 1 is made of a cross-shaped steel material has been described. However, the present invention is not limited to this case. A pair of square steel pipes 6 may be disposed on both surfaces thereof so as to be relatively displaceable, and the square steel pipes 6 may be connected to each other at adjacent portions, using a shaped steel material.
Further, it is not always necessary to form the transition portion 4 between the elastic portion 2 and the yield portion 3.

The fixing of the square steel pipe 6 and the shaft member 1 is not limited to the above-described high-strength bolt 6a.
Various fixing structures such as welding can be adopted. Further, the engaging portion for preventing excessive relative displacement between the shaft member 1 and the square steel pipe 6 is also provided with the uneven portion 2 having the shape shown in the second embodiment.
The present invention is not limited to 0 and 21, and various types of engaging portions such as a bolt and a loose hole with which the bolt engages can be applied.

[0038]

As described above, according to the composite vibration damping brace according to any one of claims 1 to 3, the steel pipe member functioning as a buckling stiffener around the shaft member can be relatively displaced. Disposed and provided with a discontinuous portion having a gap in the shaft member, and a viscoelastic damper using a viscoelastic body and a hysteretic damper played by the yielding portion of the shaft member are arranged in series. The viscoelastic damper of the viscoelastic body interposed between the elastic portion and the steel pipe member functions for small-amplitude shaking, and the hysteretic damper in the yielding portion for large-amplitude shaking, Since the energy can be effectively absorbed and the energy can be reduced, various vibrations from small amplitude to large amplitude generated in the structure can be reduced despite the simple and lightweight structure.

According to the second aspect of the present invention, an engaging portion for preventing a relative displacement of not less than a predetermined value is formed between the other of the shaft members and the steel pipe member at the discontinuous portion. Therefore, even in the event that excessive shear deformation is applied to the viscoelastic body, an effect is obtained in that the engagement portion can reliably prevent peeling or breakage of the viscoelastic body.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of a composite vibration damping brace according to the present invention.

FIG. 2 is a longitudinal sectional view of a main part of FIG.

3A and 3B are schematic views for explaining the operation of the composite vibration damping brace of FIG. 1, wherein FIG. 3A shows a state in which a tensile force is applied, and FIG. 3B shows a state in which a compressive force is applied.

4A is a perspective view showing a shape of a shaft member and the like in a second embodiment, FIG. 4B is a perspective view showing a shape of a shaft member and the like in a third embodiment, and FIG. It is a perspective view showing the shape of the shaft member etc. in the embodiment.

FIG. 5 is an exploded perspective view showing a fifth embodiment of the present invention.

FIG. 6 is a partially cutaway perspective view for explaining characteristics of the viscoelastic damper.

[Explanation of symbols]

 Reference Signs List 1 shaft member 1a, 1b end 2 elastic part 3 yield part 5, 10, 11, 12 gap 6 square steel pipe (steel pipe member) 6a high-strength bolt 7 viscoelastic body 9 flat bar 20 convex part 21 concave part

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3J048 AA03 AC01 BD08 EA38

Claims (3)

[Claims] 1. An elastic member having a large shaft area and a yielding portion having a small shaft area are formed on a shaft member made of a flat steel material or a cross-shaped steel material whose both ends are connected to a frame of a structure. A steel pipe member having a surface opposed to the surface is disposed on the surface of the composite member so as to be relatively displaceable, and the steel pipe members are connected to each other. In addition to interposing a viscoelastic body on the shaft member, the shaft member is provided with a discontinuous portion in which a gap capable of absorbing the expansion and contraction of the composite vibration damping brace is formed, and the viscoelastic body bordering the discontinuous portion is provided. A composite vibration damping brace wherein the steel pipe member is fixed to the shaft member on the side where no interposition is provided. 2. An engaging portion for preventing a relative displacement of not less than a predetermined value is formed between the other of the shaft member and the steel pipe member at the discontinuous portion. The composite vibration damping brace described in. 3. An elastic member having a large shaft area and a yielding portion having a small shaft area are formed on a shaft member made of a flat steel material or a cross-shaped steel material whose both ends are connected to a frame of a structure. A steel pipe member having a surface opposed to the surface is disposed on the surface of the composite member so as to be relatively displaceable, and the steel pipe members are connected to each other. And a discontinuous portion in which a gap capable of absorbing expansion and contraction of the composite vibration damping brace is provided in the elastic portion of the shaft member. .