JP2006161362A - Base-isolated building - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a base-isolated building which allows effective use of a building floor area on a base-isolated story without hindering movement of rolling friction dampers. <P>SOLUTION: According to the structure of the base-isolated building, an upper building section is set on a lower building section Ba in a manner relatively movable with respect to the lower building section Ba along a base isolation moving surface H, and the plurality of rolling friction dampers D are arranged astride the lower building section Ba and the upper building section. Each rolling friction damper D is formed of damper arms 2 which are pivotally connected to the lower building section Ba and the upper building section in a manner rockable with respect to the same, and a joint portion 3 which pivotally connects between the damper arms 2, and applies frictional resistance against relative rocking. Each rolling friction damper D is located at a location close to a peripheral edge of the building floor area, and each joint 3 is located on a line connecting between a pivotal connection portion 10a of the damper arm 2 to the lower building section Ba and a pivotal connection portion 10b of the damper arm 2 to the upper building section, or on one side of the line close to the building peripheral edge. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In the present invention, an upper building part is installed on a lower building part so as to be relatively movable along a horizontal or substantially horizontal seismic isolation moving surface, and each of the lower building part and the upper building part is provided with the above-mentioned immunity. A damper arm pivotally connected so as to be swingable along the seismic movement surface, and the damper arms are pivotally connected to each other along the seismic isolation movement surface so as to be capable of relative swinging. The present invention relates to a base-isolated building in which a plurality of rotational friction dampers including joint portions for providing frictional resistance are attached across the lower building portion and the upper building portion.

The above-mentioned rotary friction damper is mainly composed of a pair of damper arms in which one end portions are pivotally connected by joints, and the other end of one damper arm is a lower building portion and the other damper arm is By pivotally connecting the other end of each to the upper building part, both the lower building part and the upper building part move relative to each other along the seismic isolation moving surface due to the rolling due to the earthquake. It is said that the damper arms swing relative to each other around the joint, and the damper effect is exerted on the building by the swing resistance (see, for example, Patent Documents 1, 2, and 3). Accordingly, with relative movement between the lower building part and the upper building part, both damper arms and the joint part that pivotally connects them move in a wide range along the seismic isolation moving surface. There is no obstacle on the trajectory.
Conventionally, as this type of base-isolated building, as shown in FIG. 9, each rotary friction damper D includes a pivot joint 10a of the damper arm 2 with respect to the lower building part Ba and a damper arm 2 with respect to the upper building part Bb. It is installed in a state where the joint part 3 is located on the center side of the building from the line connecting the pivot connection part 10b.

JP-A-8-218682 (FIGS. 1 and 2) Japanese Patent Laid-Open No. 10-280726 (FIGS. 1 and 3 to 7) JP 2003-106360 A (FIG. 3)

  According to the conventional seismic isolation building described above, the movement trajectory of the joint portion is located on the center side of the building with respect to the rotary friction damper body. It is necessary to leave a space so that the part can move freely. Therefore, originally, the central part of the building, which is easy to secure a wide range for arranging equipment and piping, etc. cannot be used, and it is difficult to effectively use the building floor on the seismic isolation floor was there.

  Accordingly, an object of the present invention is to provide a base-isolated building that can solve the above-mentioned problems and can effectively use the building plane of the base-isolated floor without obstructing the movement of the rotary friction damper.

  According to a first characteristic configuration of the present invention, an upper building part is installed on a lower building part so as to be relatively movable along a horizontal or substantially horizontal seismic isolation moving surface, and the lower building part and the upper building are arranged. And a damper arm pivotally connected to each part so as to be swingable along the seismic isolation moving surface, and the damper arms are pivotally connected relative to each other along the seismic isolation moving surface. In a base-isolated building in which a plurality of rotational friction dampers having joint portions that provide frictional resistance against relative oscillation are attached across the lower building portion and the upper building portion, each of the rotational friction dampers is a building The damper arm is pivotally connected to the lower building part, and the damper arm pivotally connected part to the upper building part. Connecting lines, or the joint portion on the building outer peripheral side of the line is in a place where it is installed in a state located.

  According to the first characteristic configuration of the present invention, each of the rotational friction dampers is installed at a position closer to the outer peripheral side than the central portion on the building plane, and thus is continuously connected to the central portion on the building plane. A large space is secured. And the joint part is on a virtual line connecting the pivot connection part of the damper arm with respect to the lower building part and the pivot connection part of the damper arm with respect to the upper building part, or on the outer periphery side of the building from the virtual line. Since the lower building part and the upper building part are relatively moved laterally due to an earthquake, etc., the damper arm and joint move while moving in the area closer to the outer periphery of the building than the imaginary line. In addition to being able to demonstrate the damper effect, it is possible to prevent the movement trajectory of the damper arm and joints from entering into the wide space in the center of the building. It becomes possible to install piping and the like. Therefore, it is possible to effectively use the building plane of the seismic isolation floor while exhibiting the function of the rotational friction damper.

  According to a second characteristic configuration of the present invention, an even number of the rotational friction dampers are provided, and the rotational friction dampers forming a pair are arranged to face each other with a central portion in the building plane.

In the rotary friction damper, as shown in FIG. 8, when the two pivot joints 10a and 10b move relative to each other along a predetermined direction, the mutual separation distance changes even if the linear movement amount is constant. Then, the amount of change in angle between the pair of damper arms 2 also differs. According to the example in the figure, the angle θ between the damper arms when the other pivot connection part 10b moves from one pivot connection part 10a to ae (constant interval) is e from the position a. Naturally, the position of is larger, but the amount of change in angle is also greater between d and e than between a and b. And since the total amount of rotational friction force by the damper is proportional to the amount of change in angle (rotation angle), when attention is paid to one rotational friction damper, if relative movement between the lower building part and the upper building part of the building occurs, A difference in the damper effect tends to occur between the beginning and end of movement.
According to the second characteristic configuration of the present invention, in addition to achieving the above-described operation and effect of the first characteristic configuration of the present invention, an even number of the rotational friction dampers are provided and a pair of rotational frictions are provided. The dampers are placed opposite to each other across the center of the building plane, so as the damper arm angle of one rotating friction damper decreases with the relative lateral movement of the lower building part and the upper building part, the other It becomes possible to move the damper arm angle of the rotary friction damper so as to increase. As a result, the difference in frictional force can be averaged, and variations in the damper effect at the beginning and end of movement can be reduced.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the parts indicated by the same reference numerals as those in the conventional example indicate the same or corresponding parts.

1 and 2 show an embodiment of the base-isolated building of the present invention. The base-isolated building B has a horizontal or almost horizontal base-isolated moving surface on a base portion (corresponding to a lower building portion) Ba. The building part (corresponding to the upper building part) Bb is installed so as to be relatively movable along H, and is not shown in the figure, but the building part is connected via a seismic isolation device provided at an appropriate place. Bb is supported on the base Ba.
A plurality of seismic isolation dampers for attenuating relative rolls during an earthquake are attached across the foundation part Ba and the building part Bb.

As shown in FIGS. 3 and 4, the seismic isolation damper includes a damper arm 2 pivotally connected to a base part Ba and a building part Bb so as to be swingable along the seismic isolation moving surface H, respectively. The damper arm 2 is composed of a rotary friction damper D provided with a joint portion 3 for pivotally connecting the damper arms 2 along the seismic isolation moving surface H so as to be relatively swingable and providing frictional resistance against the relative swing. ing.
The damper arm 2 is composed of a plurality of metal arm plates 4 that are arranged side by side so as to overlap each other in the vertical direction.
In the present embodiment, the damper arm 2a whose one end is pivotally connected to the base part Ba is two arm plates 4, and the damper arm 2b whose one end is pivotally connected to the building part Bb is three pieces. Arm plate 4. The other end portions of the damper arms 2a and 2b are arranged in a state where the arm plates 4 are alternately overlapped with each other in the joint portion 3, and are pivotally connected by bolts 5 and nuts 6 penetrating them. Yes. Between the overlapping arm plates 4, friction pads 7 are provided to apply frictional force to the bolts 5 when rotating relative to each other around the axis of the bolt 5, while the upper arm plate 4 and the bolts 5 are interposed. A metal disc spring 8 that can adjust the tightening force of the bolt and nut to a predetermined value is interposed between the enlarged diameter head portion 5a and the lower arm plate 4 and the nut 6, respectively. is there.
Therefore, as both damper arms 2a and 2b rotate relative to each other around the bolt 5 axis, a tightening force by the bolt nut and a rotational resistance force correlated with the friction coefficient of the friction pad 7 can be applied. It becomes.
Incidentally, the friction pad 7 is, for example, a brake pad in which a friction fiber obtained by blending a metal fiber such as brass or iron with an aramid fiber (trade name: Kevlar kevlar) is bonded with a thermosetting resin and hardened in a plate shape. It is composed of materials.
Also, one end of the damper arm 2a (or 2b) is bolted to the attached portion 9a (or 9b) provided in the base portion Ba (or building portion Bb) so as to be rotatable around the vertical axis. ing. The bolt connecting portion 10a (or 10b) corresponds to a pivot connecting portion.
In the present embodiment, as described above, the number of the arm plates 4 of the damper arm 2a on the base portion Ba side and the damper arm 2b on the building portion Bb side is designed differently. Is designed so that the total effective cross-sectional areas of the arm plates 4 of both damper arms 2a and 2b are the same (or substantially the same), and there is a tensile force at both ends of the rotary friction damper D. The tensile cross-sectional strength when acting and becoming linear is the same (or substantially the same) for both damper arms 2a and 2b. Therefore, according to the rotational friction damper D, in addition to being able to attenuate the relative lateral movement between the base part Ba and the building part Bb, it also serves as a stopper for setting the upper limit value of the relative lateral movement. be able to.

Next, the arrangement of each rotary friction damper D will be described.
Here, a rectangular planar seismic isolation building in which four rotational friction dampers D are installed will be described as an example.
As shown in FIG. 2, each rotational friction damper D is installed at each of four corners with a central portion on the building plane. And 9a in a figure is a to-be-attached part formed in the base part Ba, 9b has shown the to-be-attached part formed in building part Bb. Moreover, the position of the joint part 3 is installed in the state located on the line which connects the bolt connection part 10a, 10b of the both ends of the rotational friction damper D in the top view, or the building outer peripheral side from the line.
As shown in FIG. 5, the posture of the rotational friction damper D when the building portion Bb moves vertically and horizontally in the plan view with respect to the base portion Ba is as shown in FIG. 5. The movement trajectories of the joint part 3 and the damper arm 2 are set on the outer edge side on the building plane, and the central part on the building plane can be vacated as a space that can be used for other purposes.

In addition, the restoring force characteristic of each rotating friction damper D when the building part Bb moves in the direction of the white arrow shown in FIG. 2 is as shown in FIG. 6 and shows four geometrical asymmetries. By combining the friction damper D, the restoring force characteristics of the entire building are as shown in FIG. 7, and the geometric asymmetry can be eliminated. The horizontal axis of the graph represents the amount of deformation, and the vertical axis represents the load.

  According to the base-isolated building of the present embodiment, it is possible to effectively use the building plane of the base-isolated floor while exhibiting the vibration damping function by the rotary friction damper. And it becomes possible to act the damping force with few variations with respect to the lateral movement to which direction, and it becomes possible to exhibit the stable damper effect.

[Another embodiment]
Other embodiments will be described below.

<1> The seismic isolation building is not limited to the one in which a base isolation layer is formed between the foundation part described in the previous embodiment and the building part on the base part. A so-called “intermediate base-isolated building” in which a seismic layer is formed may be used as long as a base-isolating layer is formed between the lower building portion and the upper building portion. These are collectively referred to as seismic isolation buildings.
<2> The rotational friction damper is not limited to the type described in the previous embodiment. For example, the number of arm plates constituting the damper arm can be set as appropriate. Moreover, the detailed structure of the joint part 3 can also be changed suitably. These are collectively referred to as rotational friction dampers.
Further, the number of installations is not limited to four as described in the previous embodiment, and two or more may be provided. However, in order to be able to eliminate the geometric asymmetry of the restoring force characteristic, it is preferable to provide an even number of rotational friction dampers. Furthermore, it is more preferable to provide a multiple of 4 rotational friction dampers.

  In addition, as mentioned above, although the code | symbol was written in order to make contrast with drawing convenient, this invention is not limited to the structure of an accompanying drawing by this entry. In addition, it goes without saying that the present invention can be carried out in various modes without departing from the gist of the present invention.

Side sectional view showing the main part of the base-isolated building Floor plan of seismic isolation building Side sectional view showing the installation of the rotary friction damper Plan view showing the installation of the rotary friction damper Schematic plan view showing the deformation of the damper as the building moves laterally Diagram showing restoring force characteristics of each damper The figure which shows the restoring force characteristic of the damper in the whole seismic isolation building Schematic plan view showing the relationship between the amount of lateral movement of the building and the angle of the damper arm Main part plan view showing the installation status of dampers in conventional seismic isolation buildings

Explanation of symbols

2 Damper arm 3 Joint part 10a Bolt connection part (equivalent to pivot support part on the base part side)
10b Bolt connection (corresponding to the pivot connection on the building side)
Ba foundation (equivalent to lower building)
Bb Building (equivalent to upper building)
D Rotating friction damper H Seismic isolation surface

Claims (2)

An upper building part is installed on the lower building part so as to be relatively movable along a horizontal or substantially horizontal seismic isolation moving surface, and each of the lower building part and the upper building part is provided with the seismic isolation moving surface. A damper arm pivotally connected so as to be swingable along the axis, and the damper arms are pivotally connected to each other along the seismic isolation moving surface, and a frictional resistance is given to the relative swing. A rotary friction damper having a joint part is a base-isolated building in which a plurality of rotational friction dampers are attached across the lower building part and the upper building part,
Each of the rotational friction dampers is installed at a position closer to the outer peripheral side than the central part on the building plane, and the pivot connection part of the damper arm with respect to the lower building part, and the damper arm with respect to the upper building part The seismic isolation building installed in the state which the said joint part is located on the line which ties to the pivot connection part of this, or the building outer peripheral side from the line.   The seismic isolation building according to claim 1, wherein an even number of the rotational friction dampers are provided, and the pair of rotational friction dampers are arranged to face each other across a central portion in a building plane.

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