Seismic damping device and method for designing seismic damping device

Abstract

To exhibit a desired vibration control effect by a simple constitution.SOLUTION: A vibration control device 1 includes: a vibration control mass body 16s; an X direction elastic part 2 for defining first resonance frequency (ωOPTX) in the X direction; and a Y direction elastic part 3 for defining second resonance frequency (ωOPTY) in the Y direction. The X direction elastic part 2 includes: a first main elastic element 21 connected to a building 91 and connected to the vibration control mass body 16s; and a first sub elastic element 22 connected to the building 91 and connected to the vibration control mass body 16s. The first main elastic element 21 includes a first main elastic member 211. The first sub elastic element 22 includes: a first sub elastic member 221; and a first attenuation member 222 connected in series with respect to the first sub elastic member 221. The Y direction elastic part 3 includes: a second main elastic element 31 connected to the building 91 and connected to the vibration control mass body 16s; and a second attenuation element 32 connected to the building 91 and connected to the vibration control mass body 16s.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a seismic damping device and a method for designing a seismic damping device. [Background technology]

[0002] Tuned mass dampers are a well-known technology for reducing the amplitude and acceleration of vibrations that occur in buildings when they are subjected to seismic activity such as earthquakes or strong winds. A tuned mass damper has a resonant frequency set to tune with the building's natural frequency and a damping constant appropriately set to suppress the vibration of the mass. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2013-208189 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] Buildings subject to seismic damping may have different natural frequencies depending on the direction in which the vibration acts. For example, if a building has a rectangular floor plan, the natural frequencies in the direction of the longer side and the direction of the shorter side will be different. A tuned mass damper exhibits seismic damping effects only near the tuned natural frequency, but if the restoring force element is isotropic, the resonant frequencies in the two plane directions cannot be set to different values. Therefore, for example, in a situation where the natural periods in the direction of the longer side and the shorter side of a building are significantly different, if the resonant frequency of the tuned mass damper is tuned to the natural frequency in the direction of the longer side, it will not be able to fully exert a seismic damping effect against vibrations acting in the direction of the shorter side.

[0005] When an object to be seismically controlled has different natural frequencies in two mutually orthogonal directions, the resonant frequency of the tuned mass damper is sometimes set to the midpoint of the respective natural frequencies. However, with such a setting, the resonant frequency of the tuned mass damper does not exactly match the natural frequencies in each direction, so the desired seismic damping effect may not be obtained. Patent Document 1 discloses a seismic damping device that can adjust the period in each of two mutually orthogonal directions. With this device, since natural period adjustment can be performed in two directions, the response of the building in those two directions can be reduced.

[0006] Synchronized mass dampers are being applied not only to large-scale buildings, but also to medium-sized buildings in recent years. Furthermore, their application extends beyond buildings such as skyscrapers to civil engineering structures such as bridges. When applying seismic damping devices to these new types of structures, there is a desire to further simplify the configuration of the seismic damping devices.

[0007] Therefore, the present invention provides a seismic damping device and a method for designing a seismic damping device that can exhibit a desired seismic damping effect with a simple configuration. [Means for solving the problem]

[0008] One embodiment of the present invention is a seismic damping device applied to a building. The seismic damping device comprises a mass body, a first elastic part that cooperates with the mass body to define a first resonant frequency in a first direction, and a second elastic part that cooperates with the mass body to define a second resonant frequency in a second direction intersecting the first direction. The first elastic part has a first principal elastic element connected to the building and also connected to the mass body, and a first secondary elastic element connected to the building and also connected to the mass body. The first principal elastic element includes a first principal elastic member. The first secondary elastic element includes a first secondary elastic member and a first damping member connected in series with the first secondary elastic member. The second elastic part has a second principal elastic element connected to the building and also connected to the mass body, and a second damping element connected to the building and also connected to the mass body.

[0009] The first secondary elastic element of this seismic damping device includes a first secondary elastic member and a first damping member connected in series with the first secondary elastic member. This first secondary elastic element allows the apparent spring constant of the first secondary elastic member to be changed by setting the damping coefficient of the first damping member to a predetermined value. By changing the apparent spring constant of the first secondary elastic member, the first resonant frequency of the vibration system including the first secondary elastic member can be adjusted. Therefore, the seismic damping device can achieve the desired seismic damping effect with a simple configuration of connecting the first damping member in series with the first secondary elastic member.

[0010] In the above-described seismic damping device, the first secondary elastic member may be connected to the building, and the first damping member may be connected to the mass. Furthermore, in the above-described seismic damping device, the first damping member may be connected to the building, and the first secondary elastic member may be connected to the mass. Moreover, in the above-described seismic damping device, the first main elastic member may be a bearing device having a laminated rubber structure, and the first damping member may be an oil damper. With these configurations as well, the desired seismic damping effect can be achieved with a simple configuration.

[0011] Another embodiment of the present invention is a seismic damping device applied to a building, comprising a mass body and a first resonant frequency (ω) in cooperation with the mass body in a first direction. X A first elastic part that defines ) and a second resonant frequency (ω) in a second direction that intersects the first direction in cooperation with the mass body Y This is a method for designing a seismic damping device comprising a second elastic section that defines the optimal damping constant (h). The method for designing a seismic damping device involves the steps of obtaining a mass ratio (μ) using the mass (M) of the building and the mass (m) of the mass body, and using the mass ratio (μ) to determine the optimal damping constant (h OPT The steps include obtaining the first natural frequency (Ω) in the first direction of the building. X The first optimal resonant frequency (ω) of the seismic damping device according to ) OPT·X The steps include obtaining the second natural frequency (Ω) in the second direction intersecting the first direction of the building. Y The second optimal resonant frequency (ω) of the seismic damping device according to ) OPT·Y The steps include obtaining the optimal damping constant (h OPT ) and the first optimal resonant frequency (ωOPT·X ) is used to obtain the spring constant (k X ) of the first main elastic element that constitutes the first elastic part, and the first auxiliary elastic element that constitutes the first elastic part. The spring constant (k X ’) of the first auxiliary elastic member included in the first auxiliary elastic element and the damping coefficient (c X ) of the first damping member, and a step of obtaining; using the second optimal resonance frequency (ω OPT·Y ) to obtain the spring constant (k Y ) of the second main elastic element that constitutes the second elastic part, and obtaining the damping coefficient (c OPT ) of the second damping element that constitutes the second elastic part using the optimal damping constant (h Y ), and having.

[0012] According to this method, a vibration damping device that can exhibit a desired vibration damping effect with a simple configuration can be designed.

Effect of the Invention

[0013] According to the present invention, a vibration damping device and a method for designing a vibration damping device that can exhibit a desired vibration damping effect with a simple configuration are provided.

Brief Description of the Drawings

[0014] [Figure 1] FIG. 1 is a perspective view showing a building with a vibration damping device installed. [Figure 2] FIG. 2 is an exploded perspective view showing the structure of the vibration damping device. [Figure 3] FIG. 3(a) is a side view of the vibration damping device shown in FIG. 2 as viewed from the Y direction. FIG. 3(b) is another side view of the vibration damping device shown in FIG. 2 as viewed from the X direction. [Figure 4] FIG. 4 is a plan view of the vibration damping device shown in FIG. 2 as viewed from the Z direction. [Figure 5] FIG. 5 is a diagram showing the vibration damping device shown in FIG. 2 as a mechanical model. [Figure 6] FIG. 6(a) is a diagram showing the mechanical model in the X direction in the vibration damping device shown in FIG. 2. FIG. 6(b) is a diagram showing the mechanical model in the Y direction in the vibration damping device shown in FIG. 2. [Figure 7] Figure 7 is a flowchart showing the main steps in designing a seismic damping device. [Figure 8] Figure 8(a) is a side view of the modified seismic damping device as seen from the Y direction. Figure 8(b) is a side view of the modified seismic damping device as seen from the X direction. [Figure 9] Figure 9(a) is a side view of another modified seismic damping device, viewed from the Y direction. Figure 9(b) is a side view of yet another modified seismic damping device, viewed from the X direction. [Modes for carrying out the invention]

[0015] Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the attached drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant explanations are omitted.

[0016] <Seismic damping device> As shown in Figure 1, the seismic damping device 1 is applied to the building 91. The seismic damping device 1 suppresses the shaking or acceleration of the building 91 that occurs when vibrations are applied to the building 91 from the foundation 92 due to an earthquake or the like. Specifically, the seismic damping device 1 suppresses the shaking or acceleration of the building 91 in a first direction and also suppresses the shaking or acceleration of the building 91 in a second direction.

[0017] Here, the first direction intersects with the second direction, and for example, the first direction is perpendicular to the second direction. In the following explanation, the first direction will be called the X direction and the second direction will be called the Y direction. In other words, the seismic damping device 1 suppresses the shaking or acceleration of the building 91 in the X direction and also suppresses the shaking or acceleration of the building 91 in the Y direction.

[0018] The structural characteristics of building 91 may differ depending on the direction. For example, suppose that building 91 is rectangular when viewed from above. That is, one side (long side) of building 91 is longer than the other side (short side). A building 91 with such a shape will have different structural characteristics in the direction along the long side and different structural characteristics in the direction along the short side. Structural characteristics refer to, for example, the response to vibration. Specifically, the natural frequencies of building 91 in the direction of the long side and the natural frequencies in the direction of the short side are different from each other. In the following explanation, the structural characteristics of building 91 will be described using the term natural frequency.

[0019] The seismic damping device 1 can set resonant frequencies that it can tune to in different directions. In other words, the seismic damping device 1 can tune to the optimal resonant frequency (ω) that tunes to the natural frequency of the building 91 in the long-side direction (X direction). OPT·X The first optimal resonant frequency can be set, and the optimal resonant frequency (ω) that tunes to the natural frequency in the short-side direction (Y direction) can be set. OPT·Y The second optimal resonant frequency can be set. In these seismic damping devices 1, the optimal resonant frequency in the X direction (ω OPT·X ) and the optimal resonant frequency in the Y direction (ω OPT·Y These can be set independently of each other. Therefore, the seismic damping device 1 can eliminate synchronization misalignment in both the long-side and short-side directions.

[0020] Figure 2 is an exploded perspective view of the seismic damping device 1 shown in Figure 1. Figure 3(a) is a side view of the seismic damping device shown in Figure 2, viewed from the Y direction. Figure 3(b) is another side view of the seismic damping device shown in Figure 2, viewed from the X direction. Figure 4 is a plan view of the seismic damping device shown in Figure 2, viewed from the Z direction. The seismic damping device 1 includes a support frame 11, four first bearing devices 12, two second bearing devices 13, two first damping devices 14, two second damping devices 15, and a weight 16 (mass body). Note that the number of the above devices is illustrative, and the number of these devices in the seismic damping device 1 can be changed as appropriate.

[0021] The support frame 11 is the foundation of the seismic damping device 1 and is fixed to the building 91. This fixing method is rigid, and the fixing points between the support frame 11 and the building 91 are considered rigid and do not significantly affect the seismic damping characteristics. The shape of the support frame 11 shown in Figure 2 is a flat plate, but it is not limited to this shape. The support frame 11 may adopt a shape and structure that can be considered a rigid body that does not significantly affect the seismic damping characteristics.

[0022] The first bearing device 12 is fixed to the support frame 11 and the weight 16. The seismic damping device 1 includes four first bearing devices 12, each first bearing device 12 positioned relative to the corners of a rectangle on the support frame 11. The first bearing device 12 has a lower fixing surface 121 fixed to the support frame 11, an upper fixing surface 122 fixed to the weight 16, and a shear deformation portion 123 positioned between the lower fixing surface 121 and the upper fixing surface 122.

[0023] The fixing points on the lower fixing surface 121 and the upper fixing surface 122 are considered rigid bodies and do not significantly affect the seismic damping characteristics. The first bearing device 12 supports the weight 16. The first bearing device 12 is deformable in both the X and Y directions. This deformation means that the position of the upper fixing surface 122 is shifted in the X and / or Y directions relative to the lower fixing surface 121. This deformation is achieved, for example, by a shear deformation section 123 having a laminated rubber structure. Furthermore, there is no significant difference between the ease of deformation in the X direction and the ease of deformation in the Y direction of the first bearing device 12. In other words, there is no significant difference between the spring constant in the X direction and the spring constant in the Y direction of the first bearing device 12. Note that the first bearing device 12 may employ structures such as laminated rubber, rolling bearings, sliding bearings, or spherical sliding bearings.

[0024] The second support device 13 is fixed to the weight 16 and the first damping device 14. Regarding the specific configuration of the individual second support device 13, details common to the individual first support device 12 will be omitted.

[0025] The seismic damping device 1 includes two second bearing devices 13, each of which is aligned along the Y direction with respect to the support frame 11. The second bearing device 13 has a lower fixed surface 131 connected to the first damping device 14, an upper fixed surface 132 fixed to the weight 16, and a shear deformation portion 133 positioned between the lower fixed surface 131 and the upper fixed surface 132.

[0026] The first bearing device 12 was deformable in both the X and Y directions. Therefore, in the mechanical model of the seismic damping device 1 described later, the first bearing device 12 appears in the mechanical model in the X direction (see Figure 6(a)) and also in the mechanical model in the Y direction (see Figure 6(b)). On the other hand, the second bearing device 13 is deformable in the X direction but not in the Y direction. Therefore, in the mechanical model of the seismic damping device described later, the second bearing device 13 appears only in the mechanical model in the X direction (see Figure 6(a)) and not in the mechanical model in the Y direction (see Figure 6(b)).

[0027] In this embodiment, the second support device 13 does not require its lower fixing surface 131 to be fixed to the support frame 11. In this embodiment, the lower fixing surface 131 of the second support device 13 is described as not being in contact with the support frame 11. An example in which the lower fixing surface 131 of the second support device 13 is in contact with the support frame 11 will be described later as a modification.

[0028] The first damping device 14 is fixed to the support frame 11 and the second bearing device 13. The first damping device 14 can be any device as long as it is configured to set the damping coefficient to a desired value. For example, a linear oil damper may be used as the first damping device 14. The first damping device 14 is positioned, for example, between a pair of first bearing devices 12 aligned along the X direction. The first damping device 14 has a fixed end 141 fixed to the support frame 11, a fixed end 142 fixed to the second bearing device 13, and a damping force generating unit 143 that generates a damping force. The damping force generating unit 143 generates a damping force proportional to the relative velocity difference between the fixed ends 141 and 142. The first damping device 14 is positioned so that its axis is parallel to the X direction in order to generate a damping force along the X direction.

[0029] The second damping device 15 is fixed to the support frame 11 and the weight 16. The second damping device 15 is positioned, for example, between a pair of first support devices 12 aligned along the Y direction. The second damping device 15 has a fixed end 151 fixed to the support frame 11, a fixed end 152 fixed to the weight 16, and a damping force generating unit 153 that generates a damping force. The second damping device 15 is positioned so that its axis is parallel to the Y direction in order to generate a damping force along the Y direction.

[0030] Resonant frequency in the X direction (ω X ) is based on the mass of the weight 16, the spring constant of the first support device 12, the spring constant of the second support device 13, and the damping coefficient of the first damping device 14. In other words, the resonant frequency in the X direction (ω X ) is affected by the first damping device 14. In other words, the resonant frequency (ω) in the X direction is affected. X The spring constant of the second bearing device 13 is not determined solely by the mass of the weight 16, the spring constant of the first bearing device 12, and the spring constant of the second bearing device 13, but is determined by the damping coefficient of the first damping device 14. The damping coefficient of the first damping device 14 affects the spring constant of the second bearing device 13. The spring constant of the second bearing device 13, which is affected by the damping coefficient of the first damping device 14, is also called the "apparent spring constant (αkx')".

[0031] On the other hand, the resonant frequency in the Y direction (ω Y ) is based on the mass of the weight 16 and the spring constant of the first support device 12. In other words, the resonant frequency in the Y direction (ω Y ) is substantially unaffected by the second attenuation device 15.

[0032] <Mechanical model of seismic damping device> The mechanical characteristics of the seismic damping device 1 shown in Figure 1 will be explained in more detail below, with reference to the mechanical models shown in Figures 5 and 6.

[0033] The seismic damping device 1 has a damping coefficient (c) of the first damping member 222. XThe damping force based on increases the "apparent stiffness" in the X direction. By setting the "apparent stiffness" to a desired value, the resonant frequency (ω) in the X direction of the seismic damping device 1 is increased. X ) can be controlled to synchronize with building 91. In other words, the resonant frequency (ω) in the X direction of the seismic damping device 1 can be controlled. X ) increases the natural frequency (Ω) of the building 91 X ) can be adjusted. In this embodiment, the first direction, the X direction, has a short period. The second direction, the Y direction, has a long period.

[0034] In this case, the damping coefficient of the second damping member 321 in the Y direction (c Y The damping coefficient of the first damping member 222 in the X direction (c X You may also choose to set it to a larger value.

[0035] The seismic damping device 1 is attached to the target mass 91s, which is the building 91. The seismic damping device 1 has a seismic damping mass 16s, an X-direction elastic part 2 (first elastic part), and a Y-direction elastic part 3 (second elastic part). The X-direction elastic part 2 connects the seismic damping mass 16s to the target mass 91s in the X direction. The Y-direction elastic part 3 connects the seismic damping mass 16s to the target mass 91s in the Y direction. The X-direction elastic part 2 and the Y-direction elastic part 3 do not influence each other. In other words, the X-direction vibration system composed of the seismic damping mass 16s and the X-direction elastic part 2 is independent of the Y-direction vibration system composed of the seismic damping mass 16s and the Y-direction elastic part 3.

[0036] The seismic damping mass 16s is movable horizontally relative to the building 91. Specifically, the seismic damping mass 16s is movable in the X and Y directions. The seismic damping mass 16s corresponds to the weight 16 shown in Figure 1. The mass of the seismic damping mass 16s is expressed as mass (m).

[0037] The target mass 91s corresponds to building 91 shown in Figure 1. The mass of the target mass 91s is shown as mass (M).

[0038] The X-direction elastic section 2 includes a first principal elastic element 21 and a first secondary elastic element 22. The first principal elastic element 21 includes a first principal elastic member 211. The first secondary elastic element 22 includes a first secondary elastic member 221 and a first damping member 222.

[0039] The first principal elastic member 211 corresponds to the four first bearing devices 12 shown in Figure 1. One end of the first principal elastic member 211 is connected to the target mass 91s, and the other end is connected to the vibration damping mass 16s. The first principal elastic member 211 has an inherent spring constant (k X ) has.

[0040] The first secondary elastic member 221 corresponds to the two second support devices 13 shown in Figure 1. One end of the first secondary elastic member 221 is connected to the target mass 91s, and the other end is connected to the first damping member 222. The first secondary elastic member 221 has an inherent spring constant (k X It has ').

[0041] One reason for adopting the second support device 13 as the first secondary elastic member 221 is its high linearity in the relationship between load and deformation. Furthermore, other reasons for adopting the second support device 13 include its high durability against repeated vibration, large allowable deformation, and ease of design of the connection part.

[0042] The first secondary elastic member 221 is not limited to the second support device 13. For example, the first secondary elastic member 221 may be made of rubber material such as a fender or a metal spring. Examples of metal springs include coil springs, leaf springs, disc springs, and torsion bars.

[0043] The first damping member 222 corresponds to the two first damping devices 14 shown in Figure 1. The first damping member 222 has an inherent damping coefficient (c xThe first damping member 222 has one end connected to the first secondary elastic member 221 and the other end connected to the vibration-damping mass body 16s. The first damping member 222 generates a damping force corresponding to the velocity difference at both ends of the first secondary elastic member 221. In addition to its function as a damper, the first damping member 222 also has the intrinsic spring constant (k) of the first secondary elastic member 221. X It also has the function of adjusting ') to obtain the apparent spring constant (adjusted spring constant (αkx')).

[0044] In this embodiment, the first secondary elastic member 221 was connected to the seismic damping mass 16s, and the first damping member 222 was connected to the target mass 91s. This connection configuration may be reversed. That is, the first secondary elastic member 221 may be connected to the target mass 91s, and the first damping member 222 may be connected to the seismic damping mass 16s.

[0045] Furthermore, the X-direction elastic section 2, which is a mechanical system including the first secondary elastic member 221 and the first damping member 222, can also be called the adjustable elastic section. The adjustable elastic section has an adjustable spring constant (αkx'). The adjustable spring constant (αkx') is the intrinsic spring constant (k) of the first secondary elastic member 221. X ') is adjusted by the first damping member 222.

[0046] Furthermore, a configuration in which a first auxiliary elastic member 221, which is a spring element, is connected in series to a first damping member 222 such as an oil damper is generally called the Maxwell model. The Maxwell model does not generate resistance force against static loads. On the other hand, it exerts resistance force against dynamic loads. In other words, the Maxwell model including the first auxiliary elastic member 221 and the first damping member 222 has an apparent spring constant (dynamic stiffness) in the vibration state. The resonant frequency in the X direction with the Maxwell model added is (ω X ) is the resonant frequency in the Y direction without addition (ω Y) becomes higher than ). As a result, it becomes possible to set the natural periods of the two directions of the seismic damping device 1 separately. In other words, by arranging the first auxiliary elastic member 221 (spring element) in series with the first damping member 222 (oil damper) in the X direction, the problem of different natural periods in the two directions of the seismic damping device 1 can be solved. In this case, by appropriately setting the stiffness (spring constant) of the first auxiliary elastic member 221 (spring element) and the damping coefficient of the first damping member 222 (oil damper), the resonant frequency (ω) in the X direction can be set. X ), Y-direction resonant frequency (ω Y ) and the equivalent damping constant are set individually.

[0047] The Y-direction elastic section 3 includes a second principal elastic element 31 and a second damping element 32. The second principal elastic element 31 includes a second principal elastic member 311. The second damping element 32 includes a second damping member 321.

[0048] The second principal elastic member 311 corresponds to the four first bearing devices 12 shown in Figure 1. One end of the second principal elastic member 311 is connected to the target mass 91s, and the other end is connected to the vibration damping mass 16s. The second principal elastic member 311 has an inherent spring constant (k Y ) has.

[0049] The second damping member 321 corresponds to the two second damping devices 15 shown in Figure 1. The second damping member 321 has an inherent damping coefficient (c Y The second damping member 321 has one end connected to the vibration-damping mass 16s and the other end connected to the target mass 91s. The second damping member 321 generates a damping force corresponding to the velocity difference at both ends of the second principal elastic member 311. The second damping member 321 also functions as an attenuator.

[0050] <How to design seismic damping devices> Next, we will explain how to design the seismic damping device 1. The design of the seismic damping device 1 is, in other words, the spring constant (k) of the first principal elastic member 211 shown in the mechanical model in Figures 5 and 6. X ), the spring constant (k) of the first secondary elastic member 221 X ') and damping coefficient of the first damping member 222 (c XThe goal is to determine the spring constant (k) of the second principal elastic member 311. Furthermore, the design of the seismic damping device 1 involves determining the spring constant (k) of the second principal elastic member 311. Y ) and the damping coefficient of the second damping member 321 (c Y The goal is to determine the following. Figure 7 is a flowchart showing the main steps in the method for designing the seismic damping device 1.

[0051] First, the mass ratio (μ) is obtained (step S1). The mass ratio (μ) is the ratio of the mass [m] of the weight 16 (seismic damping mass 16s) to the mass [M] of the building 91 (target material mass 91s), as shown in equation (1). First, the mass (m) of the weight 16 is set. The mass (m) may be determined by comprehensively considering the desired seismic damping performance, the size of the installation site for the seismic damping device 1, the structural strength of the building 91, etc. Once the mass (m) of the weight 16 is determined, the mass ratio (μ) can be obtained by equation (1).

number

[0052] Next, the optimal damping constant (h OPT ) is obtained (step S2). Optimal damping constant (h OPT The optimal damping constant (h) is calculated based on the mass ratio (μ), as shown in equation (2). OPT The value is determined by the mass (m) of weight 16 and the mass (M) of building 91, and is therefore common to both the X and Y directions.

number

[0053] Next, the optimal resonant frequency in the X direction (ω OPT·X ) is obtained (step S3). Optimal resonant frequency (ω OPT·X ) is the natural frequency in the X direction of building 91 (Ω X It is set based on ). In the following explanation, the optimal resonant frequency in the X direction (ω OPT·X ) is the optimal resonant frequency (ω) in the Y direction. OPT·Y Assume that it is higher than ). In other words, assume that the period of building 91 is on the short-period side in the X direction and on the long-period side in the Y direction. Optimal resonant frequency in the X direction (ω OPT·XThe optimal setting formula for a tuned mass damper, which is common in the X direction, may be used. For example, formula (3) may be used as the optimal setting formula. Note that in formula (3), Ω X This is the natural frequency of building 91 in the X direction.

number

[0054] Next, the optimal resonant frequency in the Y direction (ω OPT·Y ) obtain (step S4). Optimal resonant frequency in the Y direction (ω OPT·Y ) may be calculated using a general optimal setting formula for a tuned mass damper in the Y direction. For example, formula (4) may be used as the optimal setting formula. Note that in formula (4) Ω Y This is the natural frequency of building 91 in the Y direction.

number

[0055] In addition, in a typical design, the optimal resonant frequency in the X direction of the seismic damping device 1 is determined by equations (3) and (4) (ω OPT·X ) and the optimal resonant frequency in the Y direction (ω OPT·Y ) and the optimal damping constant (h OPT The natural frequencies (Ω) of the building 91 in two planar directions (X direction and Y direction) are determined. Then, the stiffness of the spring elements and the damping coefficient of the damping elements constituting the seismic damping device 1 are determined accordingly. X , Ω Y If the values ​​are different, it is naturally necessary to set the vibration frequency in the X direction, the vibration frequency in the Y direction, and the damping constant of the seismic damping device 1 to different values ​​individually.

[0056] First, the values ​​of the elements constituting the Y-direction elastic part 3 are determined (S5). Specifically, in step S5, the spring constant (k) of the second principal elastic member 311 is determined. Y ) and the second damping coefficient (c) of the second damping member 321 Y) and are determined. The Y direction is the long-period side. The Y-direction elastic part 3 is a normal mechanical model composed of a spring element and a damping element. Therefore, the optimal frequency on the long-period side (ω OPT·Y The spring constant (k) of the second principal elastic member 311 is set to match ). Y ) is determined, along with the optimal damping constant (h OPT·Y The second damping coefficient (c) of the second damping member 321 is set to match ). Y Determine the spring constant (k) of the second principal elastic member 311. Y The second damping coefficient (c) can be calculated using equation (5). Y ) can be found by equation (6).

number

number

[0057] Next, the values ​​of the elements constituting the X-direction elastic part 2 are determined (S6). Specifically, in step S6, the spring constant (k) of the first principal elastic member 211 is determined. X ) and the spring constant (k) of the first secondary elastic member 221 X ') and the first damping coefficient (c) of the first damping member 222. X ) and decide.

[0058] The X direction is the short-period side. Since the first principal elastic member 211 and the second principal elastic member 311 are the same member, the spring constant (k) of the first principal elastic member 211 is X ) is the spring constant (k) of the second principal elastic member 311. Y This is the same value as ). In the X-direction elastic section 2, the "optimal resonant frequency on the short-period side (ω OPT·X ) and optimal damping constant (h OPT It is necessary to match the resonant frequency in the X direction and the equivalent damping constant of the seismic damping device 1 to the given value. However, the spring constant (k) of the first secondary elastic member 221 in the first secondary elastic element 22 of the seismic damping device 1 is also necessary. X ') and the first damping coefficient (c) of the first damping member 222. XIt cannot be obtained by a simple formula. Therefore, in the actual design, through parameter studies using numerical calculations, etc., the spring constant (k OPT·X ’) of the first auxiliary elastic member 221 and the first damping coefficient (c OPT ) of the first damping member 222 that meet the condition of “making the resonance frequency (ω X ) on the short-period side and the optimal damping constant (h X ) of the seismic isolation device 1 match the resonance frequency and equivalent damping constant in the X direction” are explored.

[0059] <Function and Effect> The seismic isolation device 1 includes a seismic isolation mass body 16s, an X-direction elastic part 2 that cooperates with the seismic isolation mass body 16s to define a first resonance frequency (ω OPT·X ) in the X direction, and a Y-direction elastic part 3 that cooperates with the seismic isolation mass body 16s to define a second resonance frequency (ω OPT·Y ) in the Y direction intersecting the X direction. The X-direction elastic part 2 has a first main elastic element 21 connected to the building 91 and connected to the seismic isolation mass body 16s, and a first auxiliary elastic element 22 connected to the building 91 and connected to the seismic isolation mass body 16s. The first main elastic element 21 includes a first main elastic member 211. The first auxiliary elastic element 22 includes a first auxiliary elastic member 221 and a first damping member 222 connected in series to the first auxiliary elastic member 221. The Y-direction elastic part 3 has a second main elastic element 31 connected to the building 91 and connected to the seismic isolation mass body 16s, and a second damping element 32 connected to the building 91 and connected to the seismic isolation mass body 16s.

[0060] The first auxiliary elastic element 22 includes a first auxiliary elastic member 221 and a first damping member 222 connected in series to the first auxiliary elastic member 221. According to this first auxiliary elastic element 22, by setting the damping coefficient (c X ) of the first damping member 222 to a predetermined value, the spring constant (αkx’) of the apparent first auxiliary elastic element 22 can be changed. According to the change in the spring constant (αkx’) of the apparent first auxiliary elastic element 22, the resonance frequency (ω OPT·X) can be adjusted. Therefore, the seismic damping device 1 can exert the desired seismic damping effect with a simple configuration in which the first damping member 222 is connected in series with the first secondary elastic member 221.

[0061] In short, the seismic damping device 1 arranges a first secondary elastic member 221 in series with the first damping member 222 in the X direction. As a result, it is possible to set the apparent spring constant in the X direction, which is the installation direction, to a desired value, and thus the resonant frequency (ω) in the X direction can be controlled. OPT·X ) can be improved.

[0062] The seismic damping device 1 controls the amplitude of the seismic damping mass 16s with a first secondary elastic member 221 arranged in series with the first damping member 222. As a result, the response stroke of the first damping member 222 can be reduced compared to the case where only the first damping member 222, such as an oil damper, is installed. A smaller response stroke reduces the difficulty of manufacturing the first damping member 222. Furthermore, when seismic retrofitting of an existing building, the first damping member 222 can be transported using the existing elevator, thus reducing the difficulty of transportation.

[0063] The seismic damping device 1 has characteristics of the first secondary elastic member 221 and damping coefficient (c) of the first damping member 222. X The following parameters are set appropriately. As a result, it becomes possible to set the period and damping in both the X and Y directions to be the optimal synchronization conditions for the seismic damping device 1. The synchronization conditions refer to the conditions under which the seismic damping device 1 can synchronize with the building and maximize its seismic damping effect.

[0064] The seismic damping device 1 can utilize general-purpose laminated rubber or linear oil dampers. Since the seismic damping device 1 does not require the development of a dedicated product, manufacturing costs can be reduced.

[0065] The seismic damping device 1 has the same stiffness conditions in the X direction and the Y direction. Therefore, the seismic damping device 1 can have a simple configuration.

[0066] The seismic damping device 1 can be realized by a single-stage laminated rubber bearing. As a result, the height of the seismic damping device 1 can be reduced, making the size of the seismic damping device 1 more compact.

[0067] Furthermore, the seismic damping device 1 is not limited to a single-stage laminated rubber device configuration. The seismic damping device 1 may be composed of one or more stages of laminated rubber devices.

[0068] Furthermore, the effects of seismic damping device 1 are listed below. Seismic damping device 1 can exhibit a high seismic damping effect. Seismic damping device 1 can be manufactured at a relatively low cost. It can also reduce the man-hours required for the installation of seismic damping device 1. Therefore, the cost required to install seismic damping device 1 can be suppressed. For example, oil dampers with a large stroke are difficult to manufacture. Since seismic damping device 1 does not require such oil dampers with a large stroke, the design and manufacture of the components that make up seismic damping device 1 are easy. Seismic damping device 1 has a compact device size, defined by its planar area and height.

[0069] The seismic damping device 1 is easy to install. For example, when using the seismic damping device 1 for seismic retrofitting of an existing building, oil dampers with a large stroke are often large in size and difficult to disassemble and transport. In other words, oil dampers with a large stroke are difficult to transport using existing elevators. On the other hand, since the seismic damping device 1 does not require such oil dampers with a large stroke, it can be transported using existing elevators, thus reducing the difficulty of transport.

[0070] The first secondary elastic member 221 is connected to the building 91, and the first damping member 222 is connected to the seismic damping mass 16s. This configuration also allows for the desired seismic damping effect to be achieved with a simple structure.

[0071] The method for designing the seismic damping device 1 involves the steps of obtaining a mass ratio (μ) using the mass (M) of the building 91 and the mass (m) of the mass body (S1), and then using the mass ratio (μ) to determine the optimal damping constant (hOPT ) step (S2) of obtaining, and the first natural vibration frequency (Ω in the first direction of the building X ) of the seismic isolation device according to the first optimal resonance vibration frequency (ω OPT·X ) step (S3) of obtaining, and the second natural vibration frequency (Ω in the second direction intersecting the first direction of the building Y ) of the seismic isolation device according to the second optimal resonance vibration frequency (ω OPT·Y ) step (S4) of obtaining, and the optimal damping constant (h OPT ) and the first optimal resonance vibration frequency (ω OPT·X ) to obtain the spring constant (k of the first main elastic element constituting the first elastic part X ), and the first sub-elastic element constituting the first elastic part, the spring constant (k of the first sub-elastic member included in the first sub-elastic element X ’) and the damping coefficient (c of the first damping member X ) step (S5) of obtaining, and the second optimal resonance vibration frequency (ω OPT·Y ) to obtain the spring constant (k of the second main elastic element constituting the second elastic part Y ), and the damping coefficient (c of the second damping element constituting the second elastic part using the optimal damping constant (h OPT ) step (S6) of obtaining, and having.

[0072] According to this method, a seismic isolation device that can exhibit a desired seismic isolation effect with a simple configuration can be designed.

[0073] The seismic isolation device of the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the gist of the present invention.

[0074] The object on which the seismic isolation device 1 is installed is not limited to the building 91. The seismic isolation device 1 may be installed on civil engineering works such as bridges, wind turbines, and chimneys. By installing the seismic isolation device 1 on such civil engineering works, earthquake countermeasures or wind sway countermeasures can be taken. Furthermore, the seismic isolation device 1 may be installed on mechanical objects such as heavy machinery and ships. By installing the seismic isolation device 1 on such mechanical objects, vibration countermeasures can be taken.

[0075] <Modification Example 1>​​ Figures 8(a) and 8(b) show the vibration damping device 1A of modified example 1. In this embodiment, the lower fixed surface 131 of the second bearing device 13 was not in contact with the support frame 11. More specifically, this means that the lower fixed surface 131 was spaced apart from the support frame 11. As shown in Figures 8(a) and 8(b), the lower fixed surface 131 of the second bearing device 13A may be in contact with the support frame 11 via a support portion 134. The support portion 134 is positioned between the lower fixed surface 131 of the second bearing device 13 and the support frame 11. The support portion 134 is fixed to the lower fixed surface 131 of the second bearing device 13. On the other hand, the support portion 134 is not fixed to the support frame 11. In other words, the support portion 134 can slide relative to the support frame 11. With this configuration, the load of the weight 16 can be supported without affecting the spring constant of the second bearing device 13.

[0076] <Modification 2> The seismic damping device 1 of the embodiment utilized a laminated rubber device. As shown in Figures 9(a) and 9(b), the seismic damping device 1B may employ a so-called suspension type configuration. The seismic damping device 1B includes a frame 41, a wire 42, a weight 43, damping members 44X and 44Y, and an elastic member 45X. The weight 43 is suspended from the frame 41 by the wire 42. This configuration corresponds to the first principal elastic member 211 and the second principal elastic member 311 in the mechanical model of Figure 5. Furthermore, the weight 43 is connected to the frame 41 via a configuration in which the damping member 44X and the elastic member 45X are connected in series with each other in the X direction. This configuration corresponds to the first secondary elastic element 22 in the mechanical model of Figure 5. The weight 43 is then connected to the frame 41 via a damping member 44Y in the Y direction. Even with a seismic damping device 1B employing such a configuration, the desired seismic damping effect can be achieved with a simple configuration. [Explanation of Symbols]

[0077] 1,1A,1B... seismic damping device, 2... X-direction elastic part (first elastic part), 3... Y-direction elastic part (second elastic part), 11... support frame, 12... first bearing device, 13,13A... second bearing device, 14... first damping device, 15... second damping device, 16... weight (mass body), 21... first principal elastic element, 22... first secondary elastic element, 31... second principal elastic element, 32... second damping element, 91... building, 92... foundation.

Claims

1. A seismic damping device applied to a building, A mass body and, The device comprises a first elastic part that cooperates with the mass body to define a first resonant frequency in a first direction, and a second elastic part that cooperates with the mass body to define a second resonant frequency in a second direction intersecting the first direction, The first elastic portion comprises a first principal elastic element connected to the building and the mass body, and a first secondary elastic element connected to the building and the mass body. The first principal elastic element includes a first principal elastic member, The first secondary elastic element includes a first secondary elastic member and a first damping member connected in series with the first secondary elastic member. The first secondary elastic member is an elastic member having an inherent spring constant and is configured as a separate member from the first damping member. The seismic damping device comprises a second elastic element connected to the building and the mass body, and a second damping element connected to the building and the mass body.

2. The seismic damping device according to claim 1, wherein the first auxiliary elastic member is connected to the building and the first damping member is connected to the mass body.

3. The first damping member is connected to the building, The seismic damping device according to claim 1, wherein the first secondary elastic member is connected to the mass body.

4. The first main elastic member is a bearing device having a laminated rubber structure, The seismic damping device according to any one of claims 1 to 3, wherein the first damping member is an oil damper.

5. A method for designing a seismic damping device applied to a building, comprising: a mass body; a first elastic part that cooperates with the mass body to define a first resonant frequency in a first direction; and a second elastic part that cooperates with the mass body to define a second resonant frequency in a second direction intersecting the first direction, wherein the first elastic part comprises a first principal elastic element connected to the building and the mass body, and a first secondary elastic element connected to the building and the mass body, wherein the first principal elastic element includes a first principal elastic member, and the first secondary elastic element includes a first secondary elastic member and a first damping member connected in series with the first secondary elastic member, wherein the first secondary elastic member is an elastic member having an inherent spring constant and is configured as a separate member from the first damping member, and the second elastic part comprises a second principal elastic element connected to the building and the mass body, and a second damping element connected to the building and the mass body, The steps include obtaining a mass ratio (μ) using the mass (M) of the building and the mass (m) of the mass body, Using the aforementioned mass ratio (μ), the optimal damping constant (h ＯＰＴ The steps to obtain ) and The first natural frequency (Ω) of the building in the first direction Ｘ The first optimal resonant frequency (ω) of the seismic damping device according to ) ＯＰＴ・Ｘ The steps to obtain ) and The second natural frequency (Ω) in the second direction intersecting the first direction of the building Ｙ The second optimal resonant frequency (ω) of the seismic damping device according to ) ＯＰＴ・Ｙ The steps to obtain ) and The optimum damping constant (h ＯＰＴ ), and the first optimum resonance frequency (ω ＯＰＴ・Ｘ ), using the spring constant (k Ｘ ) of the first main elastic element constituting the first elastic portion, and the spring constant (k Ｘ ') of the first sub-elastic element constituting the first elastic portion, which is the spring constant of the first sub-elastic member included in the first sub-elastic element, and the damping coefficient (c Ｘ ) of the first damping member, and obtaining the same; The second optimal resonant frequency (ω ＯＰＴ・Ｙ The spring constant (k) of the second principal elastic element constituting the second elastic part is determined using the second principal elastic element. Ｙ ) is obtained, and the optimal damping constant (h ＯＰＴ The damping coefficient (c) of the second damping element constituting the second elastic portion is determined using the second damping element. Ｙ A method for designing a seismic damping device having the steps of obtaining ).

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