JP2011042962A - Boundary beam-form viscoelastic damper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enlarge the damping performance of a building in the conditions similar to the current steel-based boundary beam damper. <P>SOLUTION: A boundary beam-form viscoelastic damper 1 includes: a pair of channel steels 3 (3A, 3B) which is longitudinally overlapped in only a predetermined length with each other; a viscoelastic body disposed in a condition of being sandwiched between the overlapping sections 3a of these channel steels 3A, 3B; and reinforced concrete 5 (5A, 5B) which covers parts except damping sections R of the respective groove shape steels 3A, 3B to which viscoelastic body is disposed and which is integrally joined to a pillar 2. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a boundary beam viscoelastic damper.

  Conventionally, steel-based boundary beam dampers are known to actively utilize the yield of steel shear panels for boundary beams with short spans as damping dampers. And in order to ensure the stable restoring force and toughness for the shear panel part of a boundary beam, extremely low yield point steels, such as LY100 and LY225, and low yield point steel are used. In other words, a large energy absorption capability can be expected by incorporating a damper into a short span boundary beam where shear yield is likely to occur, and actively generating shear yield. Moreover, it has the advantage that it can be miniaturized and has a high degree of freedom in installation.

However, the steel-based boundary beam damper is expected to have the shear recovery characteristics of the steel material, so that there is a current situation that the rigidity and natural period of the building must be constrained. In other words, when the boundary beam is incorporated in the short span portion, the initial rigidity is increased and the natural period is shortened, so that the input seismic motion is increased and the design layer shear force is increased.
On the other hand, some of the boundary beam portions incorporate a viscoelastic damper instead of a steel damper. Such a viscoelastic damper has a structure in which a viscoelastic body and a steel plate are laminated in a plurality of layers, and the damping performance is ensured by increasing the contact area, thereby shortening the natural period. It is possible to prevent an increase in input seismic motion (see, for example, Patent Document 1).

  In Patent Document 1, two or more multi-layer earthquake resistant walls arranged with a certain interval are connected and integrated with a plurality of damper materials, and the damper materials are boundary beams made of mild steel, or intermediate Discloses a vibration control frame composed of a boundary beam with a hysteretic or viscous damping device interposed therebetween.

JP-A-10-331477

  By the way, when installing a damper in a stud, an inner wall of a frame, a brace or the like, an installation of a boundary beam damper is conceivable because the installation location is narrow and often subject to restrictions on the architectural plan. However, in the case of a steel-based boundary beam damper, it is preferable because it is small and has a large degree of freedom, but there is a problem that the damping performance is insufficient as described above. Moreover, in the case of the viscoelastic damper applied to the boundary beam part as disclosed in Patent Document 1, it is a structure in which viscoelastic bodies and steel materials are laminated in a plurality of layers, compared to a steel material boundary beam damper. Since it is inferior in terms of small size and large degree of freedom, it can be expected to be applied under the same construction conditions as the current steel-based boundary beam dampers, that is, under conditions that are subject to architectural planning constraints. Absent.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a boundary beam type viscoelastic damper that increases the damping performance of a building under the same construction conditions as the current steel-based boundary beam damper. .

  In order to achieve the above object, the boundary beam type viscoelastic damper according to the present invention is a short span boundary beam type viscoelastic damper incorporating a damping damper spanned between adjacent support members, A pair of groove steels that are arranged so as to be orthogonal to each other and that overlap each other by a predetermined length in the longitudinal direction, and viscoelasticity arranged between the overlapping parts of these groove steels It is characterized by having a body.

  In the present invention, because it is a structure incorporating a short span viscoelastic damper between adjacent support members, without greatly changing the initial behavior of the building by the action of the viscoelastic body sandwiched between a pair of channel steel, Attenuation performance and energy absorption capacity can be increased. Therefore, compared to the case where a steel damper is used for the boundary beam part, it is possible to prevent the natural period from being shortened and the input seismic motion from being increased, and the layer shear force for design can be reduced. is there.

  Moreover, in the boundary beam type viscoelastic damper according to the present invention, each channel steel may be covered with reinforced concrete except for the overlapping portion where the viscoelastic body is disposed.

  In the present invention, when the support member is an RC column, each channel steel can be integrally joined to the support member via reinforced concrete. In other words, even if the boundary beam type viscoelastic damper is made of RC, the viscoelastic body between the overlapping portions of both channel steels is not covered with the reinforced concrete and can function as a damping portion.

  According to the boundary beam type viscoelastic damper of the present invention, by incorporating a short span viscoelastic damper between adjacent support members, damping performance and energy absorption capacity are ensured without greatly changing the initial behavior of the building. can do. And since it becomes possible to incorporate between adjacent support members under the same construction conditions as the current steel-based boundary beam damper, it is excellent in flexibility and versatility in building planning, and cost reduction can be achieved. it can.

It is a side view of the boundary beam type viscoelastic damper by a 1st embodiment of the present invention. It is a sectional side view of the boundary beam type viscoelastic damper shown in FIG. It is a top view of a boundary beam type viscoelastic damper. FIG. 4 is a sectional view taken along line AA shown in FIG. 3. FIG. 4 is a sectional view taken along line BB shown in FIG. 3. It is the figure which looked at the boundary beam type viscoelastic damper from the base end side. It is a side view of the boundary beam type viscoelastic damper by a 2nd embodiment. It is a top view of the boundary beam type viscoelastic damper shown in FIG. It is CC sectional view taken on the line shown in FIG. It is the DD sectional view taken on the line shown in FIG.

  Hereinafter, a boundary beam type viscoelastic damper according to a first embodiment of the present invention will be described with reference to FIGS.

As shown in FIGS. 1 and 2, the boundary beam type viscoelastic damper 1 according to the first embodiment is a boundary with a short span sandwiched between columns 2 and 2 (support members) in an RC building. It is a vibration damper built in as a beam.
In the present embodiment, the description will be given below with the two pillars 2 and 2 side as the outside and the center side as the inside in the longitudinal direction of the boundary beam viscoelastic damper 1.
Here, the column 2 on which the boundary beam type viscoelastic damper 1 is bridged is made of reinforced concrete, and an inner main reinforcement 2a (see FIG. 3) is attached to an anchor bolt 6 for fixing the grooved steel 3 to be described later to the column 2. It is arranged with a predetermined interval that does not hit.

  As shown in FIGS. 1 to 4, the boundary beam viscoelastic damper 1 includes a pair of channel steels 3 (3A, 3B) overlapped by a predetermined length in the longitudinal direction, and the channel steels 3A, 3B. Covers the columns 2 except for the viscoelastic body 4 disposed in a state of being sandwiched between the overlapping portions 3a and the attenuation portion R where the viscoelastic body 4 of each channel steel 3 is disposed. The reinforced concrete 5 (5A, 5B) to be integrally joined is schematically configured.

  As shown in FIG. 3 and FIG. 4, the channel steels 3A and 3B each have a dimension longer than half the length of the interval between the columns 2 and 2, the upper and lower flanges 3d are directed in the vertical direction, and the web 3c and 3c is arranged in a state of facing each other. A rib plate 31 (see FIG. 6) having a pair of bolt holes 31a formed on the end face is provided on the base end 3b of each channel steel 3 on the column 2 side. Then, as shown in FIG. 6, the grooved steels 3 </ b> A and 3 </ b> B are arranged with the rib plate 31 flush with the side surface of the pillar 2, and the anchor bolt 6 is used with the bolt hole 31 a of the rib plate 31. It is fixed to the pillar 2. Note that the distance between the grooved steels 3A and 3B in the damping part R and the length in the longitudinal direction of the overlapping part 3a between the grooved steels 3A and 3B are set according to the performance of the viscoelastic body 4. Can do.

  As shown in FIG. 5, the viscoelastic body 4 is multi-layered, and a pair of groove shapes is formed with its surface direction directed in the vertical direction (surface direction parallel to the web 3 c of the grooved steel 3). It arrange | positions in the state clamped between the overlap parts 3a and 3a of steel 3A, 3B. That is, the viscoelastic body 4 is configured to ensure damping performance as the boundary beam type viscoelastic damper 1 by causing shear deformation and absorbing energy when an earthquake or the like occurs. In addition, as the viscoelastic body 4, a synthetic rubber system, an acrylic resin system, a urethane system, etc. are employable, for example.

  As shown in FIG. 2 and FIG. 4, the reinforced concrete 5 is composed of a main reinforcement 51, a loose reinforcement 52, and concrete 53, and an overlap portion 3 a between the channel steels 3 </ b> A and 3 </ b> B is formed from the end face of the column 2. The grooved steels 3A and 3B are covered so as to be embedded within the range up to the portion (attenuating part R), and the grooved steel 3 and the column 2 are joined so as to be rigid. The reinforced concrete 5 is separated via a buffer material 7 at the approximate center in the longitudinal direction of the boundary beam. That is, one separated reinforced concrete 5A is integrally coupled to only one channel steel 3A, and the other reinforced concrete 5B is coupled to only the other channel steel 3B.

  As shown in FIGS. 4 and 5, first slabs 8 (8A, 8B) are formed on both sides of the boundary beam type viscoelastic damper 1 (left and right in FIGS. 4 and 5). 4 and 5, the heights of the first slabs 8A and 8B located on the left and right sides of the boundary beam viscoelastic damper 1 are different, and a floor slab or the like is placed on each of the first slabs 8A and 8B. (The one-dot chain line in the figure) is arranged.

  Moreover, as shown in FIGS. 1-3, between the reinforced concrete 5A, 5B, the 2nd slab 9 made from reinforced concrete is integrally provided in each reinforced concrete 5A, 5B. The second slab 9 is arranged so as to be bridged at the upper position between the reinforced concretes 5A and 5B, and the upper surface of the second slab 9 is flush with the upper surfaces of the reinforced concrete 5A and 5B. A space S is formed between the end surfaces 5a and 5a of the reinforced concrete 5A and 5B on the lower surface 9a side of the second slab 9, and an attenuation part R is disposed in the space S, and the attenuation part R The viscoelastic body 4 is not in contact with the reinforced concrete 5A, 5B.

  As shown in FIG. 2, the main reinforcing bars 51 constituting the reinforced concrete 5 are arranged so as to extend in parallel with the longitudinal direction of the boundary beam type viscoelastic damper 1, that is, at the positions above and below the groove steel 3. However, the end portion 51 a on the column 2 side is embedded in the column 2, and the inner end portion 51 b is disposed near the end surface 5 a of the reinforced concrete 5 in the material axis direction.

As shown in FIGS. 4 and 5, a slit extending between the columns 2 and 2 is provided between the first slabs 8 </ b> A and 8 </ b> B and the reinforced concrete 5, and a belt-like first cushioning material is provided in the slit. 71 (7) is interposed. The first cushioning material 71 is for separating the first slabs 8A and 8B and the reinforced concrete 5 from each other.
As shown in FIGS. 1, 2, and 3, the slit extending in the direction perpendicular to the longitudinal direction of the boundary beam type viscoelastic damper 1 between the second slabs 9, 9 is formed in a band-shaped first. Two cushioning materials 72 (7) are interposed. The second cushioning material 72 is for dividing the second slab 9 at the center.

  The first cushioning material 71 and the second cushioning material 72 are made of, for example, foamed polyethylene or the like and absorb the deformation of the boundary beam type viscoelastic damper 1 transmitted from the reinforced concrete 5A, 5B to absorb the first slab 8 and the second cushioning material 72. It has a buffering function to prevent the slab 9 from being damaged. That is, by providing the buffer material 7, the reinforced concrete 5 and the slabs 8 and 9 are separated, and it is possible to prevent the slabs 8 and 9 from cracking when an earthquake occurs. The boundary beam viscoelastic damper 1 can be deformed without being constrained by the first slab 8 and the second slab 9, so that the vibration damping performance can be reliably exhibited.

Next, the operation of the boundary beam viscoelastic damper 1 will be described with reference to the drawings.
As shown in FIGS. 1 to 5, since the boundary beam type viscoelastic damper 1 is incorporated in a short span sandwiched between columns, the viscoelastic body 4 sandwiched between a pair of channel steels 3 </ b> A and 3 </ b> B. It is possible to increase the damping performance and the energy absorption capacity without greatly changing the initial behavior of the building due to the action. Therefore, compared with the case where a steel damper is used for the boundary beam portion, the natural period can be prevented from being shortened and the input seismic motion can be prevented from increasing, and the design layer shear force can be reduced.

  Further, in the case where the support member is the RC column 2 as in the present embodiment, each of the groove steels 3A, 3B can be integrally joined to the column 2 via the reinforced concrete 5A, 5B. Become. That is, even if the boundary beam type viscoelastic damper 1 is made of RC, the viscoelastic body 4 between the overlapping portions 3a and 3a of both the groove steels 3A and 3B is not covered with the reinforced concrete 5 and functions as the damping portion R. Can be made.

  As described above, in the boundary beam type viscoelastic damper according to the first embodiment, by incorporating the viscoelastic damper in a short span sandwiched between the columns, the initial behavior of the building is attenuated without greatly changing. Performance and energy absorption capacity can be secured. And with the same construction conditions as the current steel-based boundary beam damper, it can be incorporated into a short span sandwiched between columns, so it has excellent flexibility and versatility in building planning, and cost reduction. Can be planned.

Next, a second embodiment of the present invention will be described with reference to the accompanying drawings, but the same or similar members and parts as those of the first embodiment described above are denoted by the same reference numerals and description thereof is omitted. A configuration different from the first embodiment will be described.
As shown in FIGS. 7 to 10, the boundary beam type viscoelastic damper 10 according to the second embodiment is a boundary with a short span sandwiched between steel columns 12 and 12 (support members) in an S structure building. It is an example incorporated as a beam.

Specifically, in the first embodiment described above, the boundary beam type viscoelastic damper 1 is provided with the reinforced concrete 5 (see FIGS. 1 and 2), but in the S-structure building of the second embodiment. The reinforced concrete is omitted. That is, the boundary beam type viscoelastic damper 10 includes a pair of channel steels 13 (13A, 13B) overlapped by a predetermined length in the longitudinal direction, and the overlapping portions 13a, 13a of the channel steels 13A, 13B. A viscoelastic body 14 sandwiched between the two is schematically configured. The position between the overlapping portions 13 a and 13 a becomes the attenuation portion R of the boundary beam viscoelastic damper 10.
In addition, since the structure of channel steel 13A, 13B and the viscoelastic body 14 is the same as that of 1st Embodiment mentioned above, detailed description is abbreviate | omitted.

  In the second embodiment, the third slab 15 is provided above the boundary beam viscoelastic damper 10. In FIG. 8, the third slab 15 is omitted in order to make the boundary beam viscoelastic damper 10 easier to see.

The first and second embodiments of the boundary beam type viscoelastic damper according to the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and may be appropriately selected without departing from the spirit of the present invention. It can be changed.
For example, the configuration of the shape and size of the channel steels 3 and 13, the overlap length in the longitudinal direction of the dampers at the overlapping portions 3 a and 13 a, the thickness dimensions of the viscoelastic bodies 4 and 14, etc. 10 can be set as appropriate according to the installation conditions, for example, the dimensions between the columns 2 and 2.

In addition, as the support member that bridges the boundary beam type viscoelastic damper, the RC column 2 is used in the first embodiment and the S steel column 12 is used in the second embodiment. It is not limited to the structure in which the boundary beam type viscoelastic damper is incorporated in between, and the object into which the damper is incorporated may be between the earthquake resistant walls or between the earthquake resistant walls and the columns.
Furthermore, the connection between the boundary beam viscoelastic dampers 1 and 10 and the slab is not limited to the above-described embodiment, and can be appropriately handled.

1, 10 Boundary beam viscoelastic damper 2 Column (support member)
3, 3A, 3B, 13, 13A, 13B Channel steel 3a, 13a Overlapping portion 4, 14 Viscoelastic body 5, 5A, 5B Reinforced concrete 6 Anchor bolt 7 Buffer material 8 First slab 9 Second slab 12 Steel column (support Element)
15 3rd slab 71 1st shock absorbing material 72 2nd shock absorbing material

Claims (2)

A short-span boundary beam type viscoelastic damper incorporating a damping damper spanned between adjacent support members,
A pair of channel steels that are arranged so as to be orthogonal to the support member, and have overlapping portions that overlap by a predetermined length in the longitudinal direction;
A viscoelastic body disposed between the overlapping portions of these channel steels;
A boundary beam type viscoelastic damper characterized by comprising:   2. The boundary beam viscoelastic damper according to claim 1, wherein each of the channel steels is covered with reinforced concrete except for the overlapping portion where the viscoelastic body is disposed.

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