JP2000192684A - Highly damping frame for building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a building frame which has high damping performance for decreasing response vibrations of a building caused by a large earthquake or strong wind. SOLUTION: A part or the entire of pillars at peripheral portions of a building are removed on a foundation portion or an intermediate layer portion of the building, and the building is constructed so as to easily generate rotary deformation on the foundation portion or the intermediate layer portion supported by the remaining pillars. A damper for exhibiting a damping force with respect to the rotary deformation of the building is set at a location at which the rotary deformation is concentrated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a building frame having high damping performance for reducing response vibration of a building due to a large earthquake or strong wind.

[0002]

2. Description of the Related Art Conventionally, the following means have been generally adopted based on the idea that in order to reduce the response of a building in the event of an earthquake or a strong wind, the damping performance of the building should be increased. . An inter-layer damper that is installed so that damping force is generated against inter-story displacement generated when a building vibrates. A tuned mass damper (vibration damper) in which an additional weight is installed at a site (such as a top) where vibration of the building is large, and the cycle of the additional weight is synchronized with the cycle of the building to absorb the vibration energy of the building. A seismic isolation structure in which the building is supported by members (seismic isolation device) that have high vertical rigidity and low horizontal rigidity, and absorb vibration energy using dampers and the like.

[0003] The above three means have different characteristics, but they have in common that they ultimately absorb vibration energy with a damper.

When the same damper is used, the additional damping effect of the damper is almost inversely proportional to the square of the deformation between two points where the damper is installed. Considering each of the above means from this viewpoint, since the interlayer damper is mounted between the layers of the building having a very small deformation, the efficiency is low and a large number of dampers need to be mounted. The above-mentioned tuned mass damper is configured such that the additional weight is largely shaken by utilizing the resonance phenomenon, and the damper acts on the amplified deformation, so that the efficiency is high. The above seismic isolation structure uses a bearing member having a small horizontal rigidity and increases the deformation of the seismic isolation layer, so that the efficiency is also high.

[0005] As described above, the interlayer damper has a drawback that it is not only inefficient but also limited in the layout design inside the building as compared with other means.

[0006] Even in the above-mentioned tuned mass damper, since the resonance phenomenon is used, when the cycle of the building deviates from the set cycle, the efficiency is drastically reduced. Further, there is a disadvantage that both the cost of using the additional weight and the space for installing the additional weight include a negative factor.

Furthermore, even in the case of the seismic isolation structure, the seismic isolation layer is greatly shaken when the building vibrates, so that a large seismic isolation clearance with the peripheral parts (adjacent buildings, roads, etc.) must be secured. The restrictions on architectural planning are great. There is also a drawback that a flexible joint must be used for piping that straddles the seismic isolation layer.

Conventionally, as a technique aimed at solving the above-mentioned disadvantages, for example, a "high-damping structure for controlling axial deformation" according to invention A of Japanese Patent No. 2616334 discloses a rod-shaped control member extending over a plurality of floors of a building. The control member is installed above and below and connected to the building, a passive damper is interposed in the middle part, and the amount of deformation between the damper installation points is increased to increase the additional damping effect. However, this patent invention A is applied to a high-rise building where bending deformation is predominant, and a high damping effect cannot be expected for a middle-to-low-rise building (for example, up to about 15 stories) where shear deformation is dominant. In addition, it is essential to install a high-rigidity additional shaft member (control member) as an "inner pillar" in a pillar over a plurality of floors while keeping it structurally independent from the pillar. Expected to be quite difficult.

Next, the "seismic isolation structure of a high-rise building" according to Invention B of Japanese Patent No. 2713096 is a seismic isolation structure of a high-rise building in which bending deformation is predominant. A shear resistance member is placed on the leg of a high-rise building to increase the shear stiffness. I have.

[0010]

The technical concept of the present invention is quite similar to the "seismic isolation structure of a high-rise building" according to the invention B of the above-mentioned Japanese Patent No. 2713096, and will be referred to in comparison. .

First, patent invention B is a seismic isolation structure for a high-rise building in which bending deformation is predominant as described above (FIG. 1).
B). On the other hand, the building in which the present invention is implemented is rather a medium-to-low-rise building (for example, up to 15 stories) in which the shearing force and the shearing deformation are dominant (see FIG. 1A).

Secondly, Patent Invention B has, for the above object,
The components include a "shear resistance member", a "longitudinal and compressive longitudinal vibration absorbing bearing", and a "longitudinal damper". On the other hand, the invention of the present application does not require the "shear resistance member" and the "extendable / compressible longitudinal vibration absorbing bearing", and reduces the column rigidity of the outer periphery of the building (extremely zero). In addition, the present invention is characterized in that a rotational deformation is easily generated in a building as elastic deformation.

In summary, an object of the present invention is to provide a high-damping frame of a building that is particularly effective when applied to a medium- to low-rise building where shear deformation is predominant and has a large additional damping effect.

[0014]

As a means for solving the above-mentioned problems, a high-attenuation frame for a building according to the first aspect of the present invention is a high-attenuation frame for a pillar of a building outer peripheral portion in a foundation portion or a middle layer portion of the building. A part or all of the building is removed, and the building is constructed by the remaining pillars so as to easily cause rotational deformation in the base portion or the intermediate layer portion. A damper that exerts a damping force on the rotational deformation of the building is concentrated in the rotational deformation. It is characterized by being installed in a position.

According to a second aspect of the present invention, there is provided a high-attenuation frame for a building, in which part or all of the pillars on the outer peripheral portion of the building in the foundation portion or the middle layer portion are removed, and the building is left by the remaining pillars. Or, it is constructed so that rotational deformation is likely to occur in the middle layer part, and on the bottom part where the building rotationally deforms, the vertical load of the building is supported, but in the direction of the rotational deformation, a brace-type column with small resistance is used. It is characterized in that it is installed, and a damper that exerts a damping force on the rotational deformation of the building is installed at a concentrated position of the rotational deformation.

According to a third aspect of the present invention, in the high damping frame of a building according to the first or second aspect, the magnitude of the rotational rigidity of the base portion or the intermediate layer portion which is apt to cause rotational deformation is determined by the rotation. The rotational rigidity Kr is designed so that the following equation is obtained so that the amount of deformation occurring in the building is in the same order as the amount of deformation of the building itself: Σ (Fi × Hi) / Kr × H = x. However, when the foundation is fixed, it is assumed that the deformation of x occurs at the top of the building due to the external force Fi, and the Hi is set to the height at which the external force Fi acts,
Let H be the height of the building top.

Further, when the damping coefficient Cr in the rotational direction is Ω and the whole primary circular frequency is Ω, the numerical value obtained by the following equation: Cr = 1.6 Kr / Ω is used as a guide of the maximum value. It is characterized in that it is installed in a large number within a designable range.

[0018]

2A to 2C conceptually show an embodiment of a damping frame for a building according to the first and second aspects of the present invention.

FIG. 2B shows an embodiment in which some or all of the pillars at the outer periphery of the building in the base part 2 of the building 1 are removed, and the building 1 is constructed by the remaining pillars 3 so as to easily cause rotational deformation in the base part 2. The form is shown. FIG.
C is an embodiment in which some or all of the pillars of the outer peripheral portion of the intermediate layer portion 4 of the building 1 ′ are removed, and the building 1 ′ is constructed such that the remaining pillars 3 easily cause rotational deformation in the base portion 2. Is shown.

In short, a bending deformation is locally generated in a specific layer 2 or 4 of the building, and the bending deformation is coupled to the first mode of the building. By acting the damper 5 against this bending deformation, the damping performance of the whole building is dramatically improved. Therefore, the damper 5 is installed at a portion where the rotational deformation is concentrated (or largest). Even if the original building does not generate bending deformation but generates only shearing deformation, by constructing the damping frame shown in FIGS. 2B and 2C, "bending" and "shearing" are coupled. It is possible to greatly increase the attenuation of the next mode, and as a result, the response is reduced. In FIGS. 2B and 2C, the pin indicated by reference numeral 6 has rotational rigidity.

Incidentally, the design method of the high damping frame described above is based on the fact that the magnitude of the rotational rigidity at the concentrated position of the rotational deformation in the base portion 2 or the intermediate layer portion 4 which is configured to easily cause the rotational deformation as described above is determined by rotating the building. The rotational rigidity Kr is designed such that the following equation: よ う (Fi × Hi) / Kr × H = x, so that the amount of deformation occurring in the same order as the amount of deformation of the building itself. However, when the foundation is fixed as shown in FIG. 2A, x is applied to the top of the building by external force Fi.
Is defined as the height at which the external force Fi acts, and H is the height of the top of the building.

Further, when the damping coefficient Cr in the rotational direction is Ω and the whole primary circular frequency is Ω, the capacity of the damper 5 is calculated by the following equation: Cr = 1.6 Kr / Ω As many as possible, they are installed within a designable range (the invention according to claim 3).

3 to 5 show more specific embodiments of the present invention. FIGS. 3 and 4 show an embodiment in which a rotation (or bending) deformation is easily generated in the base portion 2. FIG. 5 shows an embodiment in which a rotation (or bending) deformation is easily generated in the middle layer 4 of the building. By removing some or all of the pillars on the outer periphery of the building of the layer indicated by the symbol S in the figure to reduce the vertical rigidity, and increasing the vertical rigidity of the pillar 3 left on the inner peripheral portion of the building,
Rotational rigidity is made smaller than that of a normal building to make it easier to cause rotational deformation, while maintaining substantially the same vertical rigidity as that of a normal building.

In the figure, the reference numeral 7 indicates that the vertical load of the building 1 or 1 'is supported on the bottom of the building where the building 1 or 1' is rotationally deformed. It is a brace-type support installed in a smaller configuration, and the stability of the building is ensured (the invention according to claim 2).

The damper 5 which exerts a damping force on the rotational deformation of the building is installed at a position where the rotational deformation is concentrated. As the damper 5, an oil damper, a viscous material damper, an extremely low yield point steel damper, a friction damper, and the like can be applied. The installation portion of the damper 5 is based on the premise that the S layer is liable to be rotationally deformed as described above. Ultra-low yield point steel dampers or friction dampers that do not contribute to rigidity are applied.

FIG. 6 shows the effect of implementing the high damping frame of the present invention in a 15-story building by simulation analysis. Rotational (bending) deformation was applied to the base (types of FIGS. 2B, 3 and 4). The rotational rigidity was set so that the amount of displacement of the building due to rotation (x in FIG. 2A) was equal to the amount of shear deformation of the building itself. The result of the analysis is shown in the form of a transfer function. According to FIG. 6, the peak of the transfer function is significantly lower than that of a normal building, and it can be seen that there is a very large additional attenuation effect.

[0027]

According to the high damping frame for a building according to the first to third aspects of the present invention, the present invention is particularly effective for a medium to low-rise building where shear deformation is predominant, and has a large additional damping effect. Building can be provided.

[Brief description of the drawings]

FIG. 1A is an elevational view conceptually showing a deformation property of a building in which the present invention is implemented, and FIG. 1B is a conceptual view showing a deformation property of a building in which a known invention B is implemented.

FIG. 2A is an explanatory view quantifying and showing the deformation properties of a building in which the present invention is implemented, and FIGS. 2B and 2C are elevation views conceptually showing different embodiments of the present invention.

3A and 3B are elevation views showing an embodiment of the present invention before and after deformation.

4A and 4B are elevation views showing different embodiments of the present invention before and after deformation.

5A and 5B are elevation views showing still another embodiment of the present invention before and after deformation.

FIG. 6 is a diagram showing the effect of implementing the present invention on a 15th-floor building by simulation analysis.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1 'Building 2 Basic part 3 Column remaining in inner peripheral part 4 Intermediate part 5 Damper 7 Brace type column

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[Procedure amendment]

[Submission date] December 25, 1998 (1998.12.
25)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 6

[Correction method] Change

[Correction contents]

FIG. 6

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Nobuyoshi Murai 1-5-1, Otsuka, Inzai City, Chiba Prefecture Inside the Technical Research Institute, Takenaka Corporation (72) Inventor Masahiko Higashino 1-5-1, Otsuka, Inzai City, Chiba Prefecture Takenaka Corporation Technical Research Institute

Claims (3)

[Claims] Claims: 1. A part or all of a pillar at a peripheral portion of a building in a foundation portion or a middle layer portion of a building is removed, and the building is constructed by the remaining pillars so as to easily cause rotational deformation in the foundation portion or the middle layer portion. A high-damping frame for a building, wherein a damper that exerts a damping force on the rotational deformation of the building is installed at a concentrated position of the rotational deformation. 2. A part of or all of pillars of a building outer peripheral part in a foundation part or a middle layer part of a building are removed, and the building is constructed by the remaining pillars so as to easily cause rotational deformation in the base part or the middle layer part. That the building supports the vertical load of the building on the bottom surface where the building is rotationally deformed, but that a brace-type column with a small resistance is installed in the direction of the rotational deformation, and that the building is attenuated by the rotational deformation of the building A high-damping frame of a building, characterized in that a damper that exerts force is installed at a location where rotational deformation is concentrated. 3. The magnitude of the rotational rigidity of the base portion or the intermediate layer portion, which is liable to cause rotational deformation, is determined so that the amount of deformation generated in the building by rotation is in the same order as the amount of deformation of the building itself. Formula: 回 転 (Fi × Hi) / Kr × H = x Designing the rotational rigidity Kr. However, when the foundation is fixed, it is assumed that the deformation of x occurs at the top of the building due to the external force Fi, and the Hi is set to the height at which the external force Fi acts,
Let H be the height of the building top. Also, the capacity of the damper is
Assuming that the damping coefficient Cr in the rotational direction is Ω for the whole primary circular frequency, a number determined by the following equation: Cr = 1.6 Kr / Ω is used as a guideline for the maximum value, and a large number should be installed within a designable range. 3. The method according to claim 1, wherein
The high attenuation frame of the building described in.