JPH1037515A - Brace structure using viscoelastic damper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stable vibration damping effect, a viscoelastic damper, and the effect of preventing damage to an ambient main body structure, while taking the advantages of a method of assembling the viscoelastic damper into a brace structure that it employs a simple structure and that it is less expensive. SOLUTION: A brace member comprises a viscoelastic damper and a leading yielding member 4 formed by a connecting plate 40 by which a bracket 55 projected from the viscoelastic damper and a bracket 3 secured to a building structure are connected together by the tightening force of a bolt 4B and nut 4N. Therefore, because of the relative sliding of the brackets 3, 55 and the connecting plate 40, the brace member shows a characteristic almost equal to excessive tensile and compressive stresses that work in the direction of the axis of the viscoelastic damper, absorbing the stresses.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brace structure using a viscoelastic damper used to attenuate vibration of a building structure caused by disturbance such as an earthquake or a strong wind.

[0002]

2. Description of the Related Art Along with an increase in the height of a building structure and an increase in span, there is a need for a measure for controlling vibrations (shakes) of the building structure caused by disturbances such as earthquakes and strong winds. To meet this demand, conventionally, (1) A method of improving the rigidity of a building structure by increasing the cross section of columns and beams, etc. (2) A method of improving the strength of a building structure by installing walls or braces (3) Method to improve toughness by shear reinforcement of columns and beams, etc. (4) Method to prevent input of disturbance energy such as earthquakes and strong winds into building structures, specifically, additional mass method such as TMD,
Passive damping systems with dampers, active damping systems that actively control them, and seismic isolation systems have been proposed and put into practical use.

However, among the above conventional vibration damping methods, (1)
The method of (2) has a problem that the floor height of the building structure is high, the load is increased, and the construction cost is increased. Due to the strength and rigidity, there are problems such as the surrounding main body structure being destroyed first.The method (3) has a small effect on the surrounding main body structure, but the horizontal Displacement cannot be controlled, construction becomes complicated, and there are problems in terms of construction period and construction cost.The method (4) makes it difficult to tune the additional frequency and the natural frequency of the damper and the building structure itself. When the weight of the building structure is increased, there is a problem that the construction cost of the vibration damping device and the seismic isolation device is increased.

By the way, recently, the structure is simple,
In addition, as a low-cost vibration damping method, a viscoelastic damper is incorporated in the brace structure, and the vibration of the building structure caused by disturbance such as earthquake or strong wind due to the shear deformation of the viscoelastic material filled in this viscoelastic damper. Attention has been focused on methods of damping.

The method of incorporating the viscoelastic damper into the brace structure has the advantages of simple structure and low cost as described above, but it is difficult to increase the strength of the viscoelastic damper itself. For example, when a very large vibration is applied to a viscoelastic damper due to a large earthquake or the like, the viscoelastic damper yields and breaks at first, and the vibration damping effect cannot be expected for a large vibration. In addition to the above problem, there is a problem that the viscoelastic damper that has been yielded and damaged once cannot be reused. In order to cope with this, the axial cross-sectional area of the brace structure having the viscoelastic damper is partially reduced in portions other than the viscoelastic damper, and is filled in the viscoelastic damper for normal vibration. This is attenuated by the shear deformation of the viscoelastic body.
In addition to the shear deformation of the viscoelastic body, the brace structure with a small cross-sectional area is attenuated by plastic deformation, which reduces the cross-sectional area before the viscoelastic damper yields and breaks. Causes plastic deformation, yielding of the viscoelastic damper and surrounding main structure,
It has been proposed to prevent breakage.

[0006]

However, the brace structure in which the cross-sectional area in the axial direction is partially reduced in a portion other than the viscoelastic damper, the stress applied to the axial direction of the viscoelastic damper is reduced. Direction, specifically,
Since the absorption characteristics of stress for tension and compression are different, especially for compressive stress, buckling occurs in the brace structure with a small cross-sectional area, so that stable vibration damping effect, viscoelastic damper and surrounding body There was a problem that the effect of preventing damage to the structure could not be obtained.

SUMMARY OF THE INVENTION The present invention solves the problems of the above-mentioned system in which the cross-sectional area in the axial direction of the brace structure is partially reduced in portions other than the viscoelastic damper, and a method of incorporating the viscoelastic damper into the brace structure. A visco-elastic damper that can obtain a stable vibration damping effect, a visco-elastic damper, and an effect of preventing damage to the surrounding main body structure while using the advantages of having a simple structure and low cost. It is intended to provide a brace structure.

[0008]

In order to achieve the above object, a brace structure using a viscoelastic damper according to the present invention comprises:
The brace member is formed at the end of the viscoelastic damper and the viscoelastic damper exhibits substantially equal characteristics to excessive tensile stress and compressive stress acting in the axial direction of the viscoelastic damper and absorbs these stresses. And a preceding yielding member.

[0009] Thus, for normal vibration, this is damped by the deformation of the viscoelastic damper, and for large vibration, it is reduced by the plastic deformation of the preceding yield member in addition to the deformation of the viscoelastic damper. The damping is performed, so that the preceding yield member is plastically deformed before the viscoelastic damper yields and breaks, thereby preventing the viscoelastic damper and the surrounding main structure from yielding and breaking. At this time, since the preceding yield member exhibits characteristics substantially equal to excessive tensile stress and compressive stress acting in the axial direction of the viscoelastic damper and absorbs these stresses, a stable vibration damping effect and The effect of preventing the viscoelastic damper and the surrounding main body structure from being damaged can be obtained.

In this case, as the preceding yielding member which exhibits substantially equal characteristics to excessive tensile stress and compressive stress acting in the axial direction of the viscoelastic damper and absorbs these stresses, (1) the viscoelastic damper It consists of a connecting plate that connects the protruding bracket and the bracket fixed to the building structure side with the tightening force of bolts and nuts, and absorbs excessive stress due to relative slip between both brackets and the connecting plate. (2) It is composed of a shape steel that connects the bracket protruding from the viscoelastic damper and the bracket fixed to the building structure side,
(3) composed of a shaped steel that connects a bracket protruding from a viscoelastic damper and a bracket fixed to the building structure side, by absorbing excessive stress by plastic deformation due to bending of the web of the shaped steel;
It is possible to use a steel web in which excessive stress is absorbed by plastic deformation due to shearing of the web of the section steel.

Further, as the viscoelastic damper, an outer cylinder constituting one end of a viscoelastic damper having a partition plate therein and having an opening formed at one end is provided. Using a plurality of insert plates constituting the other end of the viscoelastic damper inserted so as to face the inner wall or the partition plate of the outer cylinder and a viscoelastic body filled in the outer cylinder Can be.

Thus, the viscoelastic body and the insert plate can be restrained by the outer cylinder, so that the strength of the viscoelastic damper can be improved and a stable vibration damping effect can be obtained. Further, by inserting a plurality of insert plates so as to face the inner wall or the partition plate of the outer cylinder, the damping effect of the vibration of the viscoelastic damper per unit volume is improved, and the viscoelastic damper can be downsized. By changing the number of the partition plates and the number of the insertion plates, the vibration damping characteristics of the viscoelastic damper can be arbitrarily set.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a brace structure using a viscoelastic damper of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show a first embodiment of a brace structure using a viscoelastic damper according to the present invention. This brace structure includes a visco-elastic damper 5 and one end side of the visco-elastic damper 5, which are connected between brackets 3, 3 welded to a joint between the column 1 and the beam 2 located on a diagonal line. And the preceding yield member 4 formed in the above.

The preceding yielding member 4 is a connection plate for connecting the bracket 55 projecting from the viscoelastic damper 5 and the bracket 3 welded to the joint between the column 1 and the beam 2 by the tightening force of the bolts 4B and nuts 4N. When an excessive stress is applied in the axial direction of the viscoelastic damper 5, it overcomes the tightening force (friction force) of the bolts 4B and the nuts 4N, and the brackets 3, 55 and the connection plate 40 A relative slip occurs, thereby absorbing excessive stress. Bolt holes 3H, 3H, of both brackets 3, 55, so that relative sliding can occur between brackets 3, 55 and connection plate 40.
At least one of 55H and the bolt hole 41 of the connection plate 40 (in this embodiment, the bolt hole 41 of the connection plate 40) is formed as a long hole. The length L of the elongated hole in the longitudinal direction is designed based on the relative slippage between the brackets 3 and 55 and the connection plate 40 required for the expected maximum vibration. The preceding yielding member 4 generates a relative slip between the brackets 3 and 55 and the connection plate 40, and is substantially equal to excessive tensile stress and compressive stress acting in the axial direction of the viscoelastic damper 5. Since these characteristics are exhibited to absorb these stresses, it is possible to obtain a stable vibration damping effect and an effect of preventing damage to the viscoelastic damper 5 and the surrounding main structures such as the columns 1 and the beams 2. In addition, even if the leading yield member 4 causes relative slippage between the brackets 3 and 55 and the connection plate 40, if the vibration stops, both the brackets 3 and 55 and the connection plate 40 are connected by the bolts 4B and the nuts 4N. Since the tightening force (frictional force) acts, it has the same vibration damping function as before (before slippage occurs).

The viscoelastic damper 5 has a single partition plate 51a inside, as shown in cross section in FIG. 3 (a), and has one end formed with an opening at one end. Outer cylinder 51 having one side formed on lid 54
Two insert plates 52 constituting the other end of the viscoelastic damper 5 inserted into the outer tube 51 from the opening of the outer tube 51 so as to face the inner wall of the outer tube 51 and the partition plate 51a; Outer cylinder 5
1 and a viscoelastic body 53 made of a polymer material filled in the voids inside. In this case, the outer cylinder 51
In order to allow the sliding of the insertion plate 52 inserted therein and the deformation of the viscoelastic body 53 filled in the outer cylinder 51, the outer cylinder 51
A space 57 is formed in the innermost part. Thereby, the viscoelastic body 53 can be restrained by the outer cylinder 51, the strength of the viscoelastic damper 5 can be improved, and a stable vibration damping effect can be obtained. By inserting a plurality of insert plates 52 so as to face the inner wall and the partition plate 51a, the vibration damping effect of the viscoelastic damper 5 per unit volume is improved, and the viscoelastic damper 5 can be downsized. It becomes possible. Also,
The numbers of the partition plates 51a and the insertion plates 52 are not limited to one and two, respectively, as shown in FIG.
As shown in (b), the number of the viscoelastic dampers 5 can be arbitrarily set, for example, two or three. The other end of the viscoelastic damper 5 is connected to the bracket 56 projecting from the viscoelastic damper 5 and the bracket 3 welded to the joint between the column 1 and the beam 2 via a connection plate 6 with bolts and nuts. To make a strong connection.

FIGS. 4 and 5 show a second embodiment of the brace structure using the viscoelastic damper of the present invention. This brace structure is similar to the first embodiment, in that a brace member bridged between brackets 3 and 7 welded to a joint between a column 1 and a beam 2 located on a diagonal line is connected to a viscoelastic damper 5, The viscoelastic damper 5 is provided with a preceding yielding member 8 formed on one end side.

The preceding yielding member 8 is shaped steel members 80, 80 for firmly connecting the bracket 55 projecting from the viscoelastic damper 5 and the bracket 7 welded to the joint between the column 1 and the beam 2 by means of bolts and nuts 84. Viscoelastic damper 5
When excessive stress is applied in the axial direction of
This causes plastic deformation due to bending of the webs 81, 81, thereby absorbing excessive stress. In this embodiment, the section steels 80 and 80 are formed of a U-shaped grooved steel so that the webs 81 and 81 of the section steels 80 and 80 can be plastically deformed by bending. One flange 82, 82 of the grooved steel is joined to a bracket 55 projecting from the viscoelastic damper 5 so that the steel webs 81, 81 are parallel to each other, and the other flanges 83, 83 are joined to the column 1 and the beam 2. The bolts and nuts 84 are used to firmly connect to the brackets 7 welded to the parts. The preceding yield member 8 is made of a shaped steel 8
By causing the webs 81, 81 of 0, 80 to undergo plastic deformation due to bending, the webs 81, 81 exhibit substantially equal characteristics to excessive tensile and compressive stresses acting in the axial direction of the viscoelastic damper 5 and absorb these stresses. Therefore, it is possible to obtain a stable vibration damping effect and an effect of preventing damage to the viscoelastic damper 5 and surrounding main structures such as the columns 1 and the beams 2. In addition, the leading yield member 8 in which the webs 81 and 81 have undergone plastic deformation due to bending is replaced with a new leading yield member 8 by replacing only the leading yield member 8 as necessary.
It has the same vibration damping function as at the beginning.

The other components such as the viscoelastic damper 5 of this embodiment are the same as those of the first embodiment.

FIGS. 6 and 7 show a third embodiment of the brace structure using the viscoelastic damper of the present invention. This brace structure is similar to the first embodiment described above, in that a brace member bridged between brackets 3 and 10 welded to a joint between a column 1 and a beam 2 located on a diagonal line is connected to a viscoelastic damper 5, A preceding yielding member 9 formed at one end of the viscoelastic damper 5
It consists of and.

The preceding yielding member 9 is formed of a section steel 90 for firmly connecting the bracket 55 projecting from the viscoelastic damper 5 and the bracket 10 welded to the joint between the column 1 and the beam 2 by means of bolts and nuts 94. Then, when an excessive stress acts on the viscoelastic damper 5 in the axial direction, the web 91 of the section steel 90 undergoes plastic deformation due to shearing, thereby absorbing the excessive stress. In this embodiment, the section steel 90 is formed of an H-section steel, and a reinforcing plate 93 is provided between flanges 92 of the H-section steel so that the web 91 of the section steel 90 can undergo plastic deformation due to shearing. Weld it. The preceding yield member 9 mainly includes
By causing plastic deformation by shearing on the web 91 outside the reinforcing plate 93 welded between the flanges 92 of the section steel 90 (in addition to this, the section steel 90 is
Since it is made of a shaped steel, plastic deformation due to bending is caused in the flange 92 outside the reinforcing plate 93 welded between the flanges 92 of the shaped steel 90), and an excessive force acting in the axial direction of the viscoelastic damper 5 is obtained. It exhibits substantially the same characteristics with respect to various tensile stresses and compressive stresses and absorbs these stresses. Therefore, it has a stable vibration damping effect and the viscoelastic damper 5 and the main body structures around the columns 1 and 2. Can be obtained. The preceding yield member 9 that has undergone plastic deformation due to bending of the web 91 has the same vibration damping function as the original one by replacing only the preceding yield member 9 with a new preceding yield member 9 as necessary. Have

The other structures such as the viscoelastic damper 5 of this embodiment are the same as those of the first embodiment.

[0023]

According to the brace structure using the viscoelastic damper of the present invention, the viscoelastic damper is attenuated by the deformation of the viscoelastic damper for ordinary vibration, and the viscoelastic damper is damped for large vibration. In addition to the deformation, this is damped by the plastic deformation of the preceding yield member, thereby taking advantage of the fact that the method of incorporating the viscoelastic damper into the brace structure has a simple structure and low cost. Further, it is possible to prevent the viscoelastic damper and the surrounding main body structure from yielding and being damaged by causing plastic deformation of the preceding yield member before the viscoelastic damper yields and breaks. For this reason, for example, even if an extremely large vibration, that is, a large displacement is applied to the brace structure due to a large earthquake or the like, at least the viscoelastic damper can be reused, and the cost can be further reduced. And, in particular, the pre-yield member used in the present invention exhibits characteristics substantially equal to excessive tensile stress and compressive stress acting in the axial direction of the viscoelastic damper and absorbs these stresses, so that it is stable. An effect of damping vibration and an effect of preventing damage to the viscoelastic damper and the surrounding main body structure can be obtained.

Further, a bracket protruding from the viscoelastic damper and a bracket fixed to the building structure side are constituted by a connection plate for connecting by a tightening force of a bolt and a nut. If vibration is stopped by absorbing excessive stress due to slip, the tightening force of bolts and nuts will act on both brackets and the connection plate, so that the initial state (before slip occurs) The same vibration damping function can be exerted, and there is no need to replace it with a new preceding yield member, which can further reduce the cost.

Further, the viscoelastic damper has a partition plate inside and an outer cylinder constituting one end side of the viscoelastic damper having an opening formed at one end side, and an outer cylinder formed into the outer cylinder through the opening of the outer cylinder. By using a plurality of insert plates constituting the other end side of the viscoelastic damper inserted so as to face the inner wall or the partition plate of the cylinder and a viscoelastic body filled inside the outer cylinder In addition, the viscoelastic body and the insertion plate can be restrained by the outer cylinder, so that the strength of the viscoelastic damper can be improved and a stable vibration damping effect can be obtained. Further, by inserting a plurality of insert plates so as to face the inner wall or the partition plate of the outer cylinder, the damping effect of the vibration of the viscoelastic damper per unit volume is improved, and the viscoelastic damper can be downsized. By changing the number of the partition plates and the number of the insertion plates, the vibration damping characteristics of the viscoelastic damper can be arbitrarily set.

[Brief description of the drawings]

FIG. 1 is a front view showing a first embodiment of a brace structure using a viscoelastic damper of the present invention.

2 (a) is an enlarged front view, FIG. 2 (b) is a sectional view taken along line BB of FIG. 2 (a), and FIG. 2 (c) is a sectional view taken along line CC of FIG. .

FIG. 3 is a cross-sectional view of the viscoelastic damper (a cross-sectional view along AA in FIG. 1).

FIG. 4 is a front view showing a second embodiment of the brace structure using the viscoelastic damper of the present invention.

FIG. 5 is an explanatory view of the preceding yielding member.

FIG. 6 is a front view showing a third embodiment of the brace structure using the viscoelastic damper of the present invention.

7A and 7B are explanatory views of the preceding yielding member, wherein FIG.
FIG. 7B is a sectional view taken along line EE of FIG. 6.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Column 2 Beam 3 Bracket 4 Advance yield member 40 Connection plate 41 Slot 4B Bolt 4N Nut 5 Viscoelastic damper 51 Outer cylinder 51a Partition plate 52 Insertion plate 53 Viscoelastic body 54 Cover 55 Bracket 6 Connection plate 7 Bracket 8 Advance yield Member 80 Section steel (groove section) 81 Web 9 Prior yielding member 90 Section steel (H section steel) 91 Web 10 Bracket

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Ota 3-6-1 Kitakyuhoji-cho, Chuo-ku, Osaka-shi, Osaka Konoike-gumi Co., Ltd. (72) Inventor Hiroshige Mori Kitahoku-jiro, Chuo-ku, Osaka, Osaka 3-6-1, Konoike Gumi Co., Ltd.

Claims (5)

[Claims] 1. A brace member comprising: a viscoelastic damper; and a brace member formed at an end of the viscoelastic damper, exhibiting characteristics substantially equal to excessive tensile stress and compressive stress acting in the axial direction of the viscoelastic damper. A brace structure using a viscoelastic damper characterized by comprising a preceding yield member absorbing such stress. 2. The yielding member comprises a connection plate for connecting a bracket projecting from a viscoelastic damper and a bracket fixed on the building structure side by a bolt and nut tightening force. 2. A brace structure using a visco-elastic damper according to claim 1, wherein an excessive stress is absorbed by a relative slip with respect to. 3. The pre-yield member is formed of a shape steel connecting a bracket projecting from a viscoelastic damper and a bracket fixed to the building structure side, and excessive stress due to plastic deformation due to bending of the web of the shape steel. 2. A brace structure using a viscoelastic damper according to claim 1, wherein the brace structure is configured to absorb a vibration. 4. The pre-yield member is formed of a shape steel connecting a bracket projecting from a viscoelastic damper and a bracket fixed to a building structure, and excessive stress due to plastic deformation due to shearing of a web of the shape steel. 2. A brace structure using a viscoelastic damper according to claim 1, wherein the brace structure is configured to absorb a vibration. 5. An outer cylinder constituting one end side of a viscoelastic damper having a partition plate therein and an opening formed at one end side, and a viscoelastic damper being inserted into the outer cylinder through the opening of the outer cylinder. It is characterized by comprising a plurality of insertion plates constituting the other end side of the viscoelastic damper inserted so as to face the inner wall or the partition plate of the cylinder, and a viscoelastic body filled inside the outer cylinder. A brace structure using the viscoelastic damper according to claim 1, 2, 3, or 4.