JP3576281B2 - Seismic isolation device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a seismic isolation device that supports a structure and suppresses the vibration of the structure in response to an earthquake by seismic isolation.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, various seismic isolation devices have been proposed in order to prevent structures such as buildings from being destroyed due to vibrations caused by an earthquake.
A conventional general seismic isolation device constructs a structure 3 on a foundation 2 constructed on an excavated ground 1 as shown in a partially cutaway configuration diagram of FIG.
[0003]
At this time, a plurality of horizontal seismic isolation devices 4 are interposed between the structure 3 and the foundation 2 to support the structure by the seismic isolation device 4 and to exhibit the seismic isolation function during an earthquake. The structure 3 is prevented from being broken by excessive vibration.
27 shows another seismic isolation device 5 in which a plurality of horizontal seismic isolation devices 4 are provided between the lower part of the gantry 6 and the foundation 2 provided on the ground 1. At the same time, a plurality of vertical seismic isolation mechanisms 7 are inserted between the structure 3 and the gantry 6.
[0004]
Further, a bearing 8 is provided between the inner surface of the gantry 6 and the outer surface of the structure 3 so as to easily move in the vertical direction and restrain the horizontal direction.
Thus, the seismic isolation mechanism 7 supports the structure 3 on the gantry 6, and the seismic isolation device 4 supports the gantry 6 on the foundation 2. Thereby, the seismic isolation device 5 exerts the seismic isolation function in the horizontal direction and the vertical direction, respectively, at the time of the earthquake, and prevents the structure 3 from being destroyed by the vibration.
[0005]
Next, details of each structure in the seismic isolation devices 4 and 5 will be described.
As shown in the front view of FIG. 28, the seismic isolation device 4 is configured to be installed horizontally and exert a seismic isolation function only in the horizontal direction. That is, the support 9 is fixed to the upper part of the foundation 2, the support 10 is inserted between the support 9 and the lower part of the structure 3, and the structure 3 is supported by the support 10. I have.
[0006]
The support 10 is a laminate in which an elastic body 11 such as an anti-vibration rubber or a thin rubber plate and an iron plate 12 are laminated and adhered to each other, and has relatively low rigidity in the horizontal direction and sufficient rigidity in the vertical direction. It is set to be high.
Further, an upper end plate 13 and a lower end plate 14 are fixed to the upper and lower parts of the elastic body 11, respectively. The upper end plate 13 is fixed to the lower part of the structure 3, and the lower end plate 14 is fixed to the upper part of the support base 9. Have been.
[0007]
Here, when a horizontal earthquake occurs, the support body 10 formed of the elastic body 11 is deformed in the horizontal direction by the seismic motion, so that the seismic force is reduced and transmitted to the structure 3. The force is reduced.
Further, in the seismic isolation device 4, as described above, the elastic body 11 such as the laminated rubber of the support 10 has elasticity only in the horizontal direction and high rigidity in the vertical direction. In the device 5, it can be used as the bearing 8 by being mounted horizontally on the side surface of the structure 3.
[0008]
As described above, in the seismic isolation device 4, the elastic body 11, which is the support 10, has elasticity only in the horizontal direction and has high rigidity in the vertical direction. But does not exhibit seismic isolation function against vertical earthquake motion.
For this reason, when an earthquake motion having a large vertical shake such as a direct earthquake occurs, since the structure 3 is supported by the foundation 2 via the support 10, the vertical shake is not changed. Or, it may be amplified and transmitted to the structure 3, and a large seismic force may act on the structure 3 and the installation inside the structure.
[0009]
As a countermeasure for this, a three-dimensional seismic isolation structure that seismically isolates in the horizontal and vertical directions has been proposed. FIGS.
The seismic isolation device 15 shown in the front view of FIG. 29 is different from the elastic body in the horizontally effective seismic isolation device 4 shown in FIG. The thickness of the elastic body 17 is made sufficiently thicker, and the number of layers of the elastic body 17 is reduced so that the elastic body 17 has elasticity in the vertical direction.
[0010]
Therefore, when an earthquake occurs, the support 16 is elastically deformed in the horizontal direction and the vertical direction, respectively, due to the earthquake motion having shaking in the horizontal direction and the vertical direction, thereby absorbing the horizontal and vertical earthquake motions, respectively. It exhibits a three-dimensional seismic isolation function.
Further, in the seismic isolation device 5, by employing the seismic isolation device 15 as the seismic isolation mechanism 7, a three-dimensional seismic isolation function can be obtained by absorbing the vertical earthquake motion.
[0011]
The seismic isolation device 18 shown in the front view of FIG. 30 is a metal coil in which both ends having elasticity in the horizontal and vertical directions are fixed to the foundation 2 and the structure 3 between the foundation 2 and the structure 3. It is composed of a spring 19.
Since the coil spring 19 is elastically deformed in the horizontal direction and the vertical direction, the coil spring 19 absorbs the horizontal and vertical seismic motions and provides a three-dimensional seismic isolation function. Therefore, by using the seismic isolation device 18 in the seismic isolation device 5 as the seismic isolation mechanism 7, the seismic isolation device 18 absorbs the vertical earthquake motion and exhibits the seismic isolation function.
[0012]
The seismic isolation device 20 shown in the front view of FIG. 31 is an air spring in which air or another gas is sealed between a foundation 2 and a structure 3 in a rubber film 22 fixed on both sides by support members 21. 23, thereby supporting the structure 3.
[0013]
In the seismic isolation device 20, the horizontal and vertical elasticity of the air spring 23 absorbs the horizontal and vertical seismic motions to provide a three-dimensional seismic isolation function. Further, in the seismic isolation device 5, the seismic isolation device 20 is also used as the seismic isolation mechanism 7, thereby absorbing the vertical seismic motion and exerting the seismic isolation function.
[0014]
The seismic isolation device 24 shown in the front view of FIG. 32 is provided between the foundation 2 and the structure 3 in a state where the support body 10 made of the above-mentioned laminated rubber and the air spring 23 are connected in series above the support body 10. It is configured by inserting.
According to this configuration, horizontal seismic isolation is mainly performed by the support 10, and vertical seismic isolation is mainly performed by the air spring 23. Therefore, the horizontal elasticity of the support body 10 such as a laminated rubber and the vertical elasticity of the air spring 23 absorb the horizontal and vertical seismic motions and exhibit a three-dimensional seismic isolation function.
[0015]
The seismic isolation device 25 shown in the partially cut front view of FIG. 33 has a configuration in which a plurality of disc springs 26 are stacked and mounted on the support 10 such as the laminated rubber.
As an effect of this configuration, the horizontal movement is restricted by the upper guide 27 and the lower guide 28, which move only in the axial direction, in which the disc spring 26 is inserted into the hole of the disc spring, and the vertical movement is easily deformed. Therefore, the horizontal elasticity of the support 10 and the vertical elasticity of the disc spring 26 absorb the horizontal and vertical seismic motions to provide a three-dimensional seismic isolation function.
[0016]
The seismic isolation device 29 shown in the front view of FIG. 34 includes a bogie 32 provided with a ball bearing 31 or a friction plate that freely moves in a horizontal direction on a slide plate 30 or a rolling plate fixed to the foundation 2, and an upper part thereof. A metal coil spring 34 is interposed in the guide shaft 33 implanted in the structure 3, and the structure 3 is supported by the coil spring 34.
Further, around the carriage 32, springs 36, 36 having one ends fixed to fixtures 35, 35 fixed to the foundation 2, are connected.
[0017]
In the seismic isolation device 29 having the above configuration, horizontal seismic isolation is obtained by the bogie 32 smoothly moving on the rolling plate 30 via the ball bearing 31, and the bogie 32 is displaced by the springs 36, 36. Horizontal movement restriction and stability occur.
In addition, since the vertical seismic isolation is performed by the elastic deformation of the coil spring 34, the seismic motion in the horizontal and vertical directions is absorbed and a three-dimensional seismic isolation function is exhibited. However, the seismic isolation devices 4, 15, 18, 20, 24, 25, and 29 shown in FIGS. 28 to 34 have the following problems.
[0018]
In the seismic isolation device 4 shown in FIG. 28, the elastic body 11 of the support body 10 has elasticity only in the horizontal direction and has high rigidity in the vertical direction, so that it exhibits a good seismic isolation function against horizontal earthquake motion. However, it does not exhibit the seismic isolation function against the vertical earthquake motion, but may amplify the vertical vibration of the structure 3.
[0019]
For this reason, in the case where a strong ground motion with a large vertical vibration such as a direct type earthquake occurs, the structure 3 is supported by the foundation 2 via the support body 10, and the vertical vibration remains unchanged, or However, there is a possibility that excessive seismic force may act on the structure 3 and the installed objects installed inside the structure 3.
[0020]
In the seismic isolation device 15 shown in FIG. 29, the elastic body 17 as the support 16 is formed of a plurality of thick rubber layers, is soft in the vertical direction, and the weight of the structure 3 is constantly applied. In this state, large compressive deformation occurs in the vertical direction. In the long term, creep deformation occurs and elasticity is easily lost.
[0021]
During an earthquake, the elastic body 17 undergoes large horizontal and vertical deformations to absorb the energy of vertical and horizontal shaking. Furthermore, since the structure 3 has a soft structure in the vertical direction by the seismic isolation device 15, rocking vibration occurs due to the horizontal vibration of the structure 3.
[0022]
Due to this rocking vibration, a large vertical deformation by the seismic isolation device 15 is added between both sides of the lower surface of the structure 3 and the foundation 2. When these deformations overlap, the elastic body 17 may be easily broken by receiving a force due to excessive deformation.
[0023]
Since the compressive deformation due to its own weight in the initial state is large, the allowable deformation amount for absorbing the shaking due to the earthquake must be reduced from the viewpoint of strength design. Therefore, in this seismic isolation device 15, since the seismic force level that can be absorbed must be set to a small value, not only can the full seismic isolation function not be exerted during a large earthquake, but also the seismic isolation device breaks due to excessive deformation, The structure 3 may be damaged.
[0024]
In the seismic isolation device 18 shown in FIG. 30, since the weight of the structure 3 is supported only by the elasticity of the coil spring 19, a large compressive deformation is generated in the coil spring 19 in the initial state.
For this reason, the coil spring 19 has the same problem as the seismic isolation device 15. Accordingly, the allowable displacement in terms of the material strength of the coil spring 19 for absorbing the shaking caused by the earthquake from the initial compression state in the vertical deformation is small.
[0025]
Further, when the coil spring 19 is deformed in the horizontal direction in order to isolate in the horizontal direction, geometrical displacement fluctuation in the vertical direction occurs. These deformations overlap, and not only may the coil spring 19 break, but if the structure 3 induces complex coupled vibration, the structure 3 may be damaged.
Therefore, in the seismic isolation device 18, the allowable seismic force level must be set low, and a sufficient seismic isolation function cannot be exerted during a large earthquake.
[0026]
Also, in the seismic isolation device 20 shown in FIG. 31, since the air spring 23 is not allowed to undergo large deformation in the horizontal and vertical directions due to the restriction on the deformation of the rubber film 22, the seismic force absorbing ability due to the deformation at the time of the earthquake is reduced. It is low and therefore cannot exhibit good seismic isolation function during a large earthquake.
[0027]
In addition, since the air spring 23 has relatively low rigidity against rotation, there is a possibility that the air spring 23 may be twisted by horizontal and vertical seismic motion, or rocking vibration may occur in the structure 3.
As described above, since the air spring 23 has elasticity in the horizontal direction and the vertical direction, a complicated coupled vibration is induced in the structure 3 similarly to the seismic isolation devices 15 and 18, and the structure 3 may be damaged. was there.
[0028]
In the seismic isolation device 24 shown in FIG. 32, when the horizontal displacement between the foundation 2 and the structure 3 increases due to the shaking during a large earthquake, the displacement absorption formed by the elastic body 11 such as a laminated rubber. There is a possibility that the air spring 23 having a smaller deformation absorbing capacity will be broken first than the support body 10 having a larger capacity.
[0029]
For this reason, since the applicable limit of the seismic isolation device 24 depends on the displacement absorption capacity of the air spring 23, it is difficult to exert a sufficient seismic isolation function during a large earthquake. In addition, since the air spring 23 has low rigidity with respect to rotation, twisting is caused by horizontal and vertical seismic motions, rocking vibration is generated in the structure 3, and complicated coupled vibration is induced in the structure 3, There was a risk of damaging the structure.
[0030]
In the seismic isolation device 25 shown in FIG. 33, elasticity is imparted in the vertical direction by the disc spring 26, and elasticity in the horizontal direction is imparted by the support 10 formed of the elastic body 11 such as laminated rubber. The disc spring 26 is restrained from moving in the horizontal direction by an upper guide 27 and a lower guide 28.
[0031]
Accordingly, since the seismic isolation device 25 has elasticity in the vertical direction, regardless of the type of the elastic body, the structure 3 is shaken in the horizontal direction similarly to the seismic isolation devices 18, 20, and 24. Rocking vibration occurs in the base 3 and the vertical deformation due to the rocking is added to the vertical displacement caused by the vertical seismic motion in the seismic isolation device 25 between both sides of the lower surface of the structure 3 and the foundation 2.
[0032]
If the deformation due to the rocking overlaps with the deformation of the main body of the seismic isolation device 25 due to the vertical earthquake motion and the deformation of the structure 3 due to its own weight, the disk spring 26 may be excessively deformed, and the disk spring 26 is broken. There was a fear of doing.
[0033]
The seismic isolation device 29 shown in FIG. 34 has a function of performing seismic isolation by the elasticity of the coil spring 34 with respect to the vertical seismic motion. As in the case of the seismic isolation devices 18, 20 and 24, rocking vibration is generated in the structure 3 due to the horizontal swing of the structure 3.
[0034]
As a result, in the seismic isolation device 29 between both sides of the lower surface of the structure 3 and the foundation 2, a vertical deformation due to the locking is added to the vertical displacement due to the vertical seismic motion. When these deformations overlap, the coil spring 34 receives a force due to excessive deformation and may be broken.
In addition, since such a configuration causes complicated coupled vibration, a good seismic isolation function cannot be exhibited during a large earthquake.
[0035]
The seismic isolation device 5 also has the following problem.
The seismic isolation device 4 for the horizontal direction and the seismic isolation mechanism 7 for the vertical direction are separated, and the rocking vibration and the horizontal deformation of the structure 3 due to the seismic isolation mechanism 7 for the vertical direction are suppressed. A bearing 8 is provided between the inner side surface and the side surface of the structure 3 for easily moving up and down and restraining the horizontal direction.
[0036]
However, when the bearing 8 has a play, the play 6 is excited, or the gantry 6 supporting the bearing 8 is deformed by the horizontal inertial force or the rotational force of the structure 3. Locking vibration cannot be suppressed sufficiently. For this reason, a good seismic isolation function in three dimensions in the horizontal and vertical directions could not be exhibited during a large earthquake.
[0037]
[Problems to be solved by the invention]
The conventional seismic isolation device 4 has only a horizontal seismic isolation function. The seismic isolation devices 5, 15, 18, 20, 24, 25, and 29 have a seismic isolation function in the horizontal and vertical directions, but due to the weight of the structure 3, excessive initial deformation occurs in the vertical seismic isolation mechanism. In addition to the horizontal and vertical vibrations generated in the structure 3 due to the horizontal and vertical seismic motions, the structure 3 causes not only horizontal and vertical vibrations but also torsional vibrations of the vertical vibrations of the structure and rocking vibrations of the horizontal vibrations. There was a problem that caused complicated vibrations.
[0038]
In addition, the support 16 and the coil spring 19, which are made of thick laminated rubber, and the air spring 23 and the disc spring 26, which perform vertical seismic isolation, can be absorbed in a range of the size of a normal seismic isolation device. Small deformation.
For this reason, when each of these seismic isolation devices undergoes an excessive initial deformation due to its own weight of the structure 3, the amount of deformation for absorbing vertical vibration is restricted, so that a large earthquake or the like causes a large amount of deformation. When deformation occurred, there was a problem that sufficient seismic isolation could not be obtained.
[0039]
Furthermore, in order to enhance the seismic isolation effect, it is necessary to lower the elasticity of various seismic isolation devices to lower the natural frequency of the structure 3. The rocking vibration is easily excited by the vibration of the structure 3, and the structure 3 vibrates complicatedly, so that the seismic isolation effect cannot be exhibited.
In order to prevent rocking vibration, the seismic isolation device for the horizontal direction and the seismic isolation device for the vertical direction are separated from each other with the gantry 6 interposed therebetween, and the inner side of the gantry 6 and the side surface of the structure 3 are separated. A vertical bearing 8 may be used between them.
[0040]
However, rocking vibration of the structure 3 cannot be sufficiently suppressed due to backlash of the bearing 8 or large horizontal inertial force between the gantry 6 supporting the bearing 8 and the structure 3 or deformation due to rotational force. There was a problem that a good seismic isolation function could not be exhibited during an earthquake.
[0041]
An object of the present invention is to suppress torsional vibration and rocking vibration generated in a structure, and to suppress excessive deformation in the horizontal and vertical directions due to these vibrations, thereby to prevent horizontal and vertical seismic isolation. And to provide an excellent seismic isolation device.
[0042]
[Means for Solving the Problems]
To achieve the above purpose To The seismic isolation device according to claim 1 is Inserted between the foundation and the structure Support structure And Horizontally and vertically Multiple elastically deforming Like an elastic body Said Foundation and Said Interposed between structures Support the structure, The attenuation capacity per unit area on the underside of the structure Said Unevenly arranged so that it is larger in the outer area than the inner area on the lower surface of the structure And Horizontal and vertical Damping the displacement of It is characterized by comprising a plurality of damping mechanisms.
[0043]
The structure is supported by an elastic body that acts in the horizontal and vertical directions, and seismic excitation caused by an earthquake performs seismic isolation by the elastic body. Further, the attenuation capacity per unit area on the lower surface of the structure is larger in the outer peripheral region than in the inner region.
Therefore, by arranging a plurality of damping mechanisms acting in the horizontal and vertical directions more unevenly in the outer peripheral area than in the inner area, or by disposing a large damping capacity in the outer peripheral area, efficient seismic isolation and horizontal It has a high damping force against torsional vibration and rocking vibration caused by an earthquake and satisfactorily suppresses the vibration.
[0044]
The seismic isolation device according to the invention described in claim 2 is A plurality of pedestals attached to the support and the first damping mechanism installed on the foundation between the foundation and the structure, and between each of the pedestals and the structure; Placed The structure A guide mechanism that regulates the horizontal movement of On each of the frames, the structure is supported by being interposed between each of the frames and the structure, Vertically Multiple elastically deforming An elastic body, Similarly, each of the gantry Interposed between structures Said While supporting the structure, Said The attenuation capacity per unit area on the underside of the structure Said At the lower surface of the structure, they are arranged unevenly so that they are larger in the outer , Vertical direction Damping the displacement of It is characterized by comprising a plurality of second damping mechanisms.
[0045]
The elastic body and the damping mechanism between the foundation and the first gantry independently perform horizontal seismic isolation, and the elastic body and the damping mechanism between the first gantry and the structure independently perform vertical seismic isolation.
Furthermore, the guide mechanism inserted between the first gantry and the structure restricts the horizontal movement of the structure, smoothes only the vertical translation, and suppresses the rocking vibration.
[0046]
In addition, by arranging the damping mechanism on the lower surface of the structure so that the damping capacity per unit area is larger in the outer region than in the inner region, rocking vibration is efficiently suppressed and good three-dimensional seismic isolation performance is achieved. Can be demonstrated.
[0060]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings. Note that the same components as those of the above-described conventional technology are denoted by the same reference numerals, and detailed description thereof will be omitted.
The first embodiment relates to claim 1, and as shown in the configuration diagram of FIG. 1, the seismic isolation device 37 supports the structure 3 by being inserted between the structure 3 and the foundation 2, An elastic body 38 acting in the vertical direction and a seismic isolation mechanism 39 acting in the vertical and horizontal directions.
[0061]
The elastic body 38 is made of, for example, a thick laminated rubber, a coil spring, or the like, and a damping mechanism 39 is attached to each of the elastic bodies 38 in parallel. At this time, the damping mechanisms 39 are arranged unequally so that the damping capacity per unit area of the lower surface of the structure 3 is larger in the outer peripheral region than in the inner region of the lower surface of the structure 3.
[0062]
Next, the operation of the above configuration will be described.
The structure 3 is elastically supported by the elastic body 38 and the damping mechanism 39 is disposed, so that the vertical vibration of the structure 3 excited by the horizontal earthquake, that is, the torsional vibration and the structure Since the damping force against the rocking vibration of the rotation vibration of the object horizontal shaft can be increased, even if the structure 3 generates torsional vibration and rocking vibration due to the earthquake, the vibration can be suppressed well.
[0063]
Since the torsional displacement and the rocking displacement increase from the inner periphery to the outer periphery of the structure 3, a larger number of damping mechanisms 39 or a larger capacity are provided in the outer peripheral region of the structure 3 where the displacement increases. By arranging the damping mechanism 39, generated torsional vibration and rocking vibration are effectively suppressed.
In addition, the damping mechanism 39 arranged in the inner area on the lower surface of the structure 3 has a smaller displacement component with respect to vibration such as torsional vibration and rocking vibration than the damping mechanism 39 arranged in the outer peripheral area. The suppression effect is small.
[0064]
Therefore, in order to efficiently suppress torsional vibration and rocking vibration, the damping mechanism 39 attached to the lower surface of the structure 3 is provided with a damping capacity per unit area on the lower surface of the structure 3 so that the entire area is uniform. It is better to dispose unevenly in the horizontal and vertical directions so as to be larger in the outer peripheral region than in the inner region on the lower surface of the structure 3 as in the present invention.
[0065]
The effect of suppressing the rocking vibration will be described with reference to the schematic diagram of FIG. Here, in order to facilitate understanding of the principle, the operation is simplified, and it is assumed that the structure 3 is rocking vibrating due to horizontal seismic motion, and only the rocking vibration component is extracted and described.
[0066]
The structure shown by the dotted line in FIG. 2 rotates around 0 as shown by the solid line due to the seismic force. Assuming that this rotation angle θ is sinusoidally oscillating, θ = θ ₀ sin ωt. Where θ ₀ Represents a rotation angle amplitude, ω represents an angular velocity, and t represents time.
Further, the damping coefficients of the damping mechanisms 39 at the installation locations A to E of the respective damping mechanisms 39 are respectively represented by C ₀ , C ₁ , C ₂ And the damping force is proportional to the relative speed. The distance 1 from the center 0 to the damping mechanism 39 at each of the installation locations A to E is 0, 1/2, and 1, respectively. At this time, the rotational damping force F due to rocking _c Is given by the following equation (1).
[0067]
F _c = (C ₁ × l ² / 2 + 2C ₂ × l ² ) × (θ ₀ ω × cos ωt) (1)
[0068]
The rotational damping force F when the total damping constant (capacity) of the five damping mechanisms 39 attached to the structure 3 is 10 and the capacities of the respective damping mechanisms 39 are two equal arrangements _c1 Is as in the following equation (2).
[0069]
F _c1 = 5 × l ² × (θ ₀ ω × cos ωt) (2)
[0070]
Further, as an example in which the damping capacity per unit area of the lower surface of the structure 3 by the damping mechanism 39 is unequal to be larger in the outer peripheral region than in the inner region of the lower surface of the structure 3, C ₀ = 0, C ₁ = 1, C ₂ = 4.
Rotation damping force F in this case _c2 Is as in the following equation (3). Note that the entire attenuation capacity is the same as in the case of the uniform arrangement.
[0071]
F _c2 = 8.5 × l ² × (θ ₀ ω × cos ωt) (3)
[0072]
At this time, the damping constant of the vertical translation from the above is the same in any arrangement, but the rotational damping force is assumed to be the non-uniform arrangement in which the damping mechanism 39 has a large damping capacity on the outer peripheral side as in the first embodiment. , Compared to the case of uniform arrangement, _c2 / F _c1 = 1.7 times larger. Therefore, the rocking vibration of the structure 3 can be more efficiently suppressed by making the damping capacity non-uniformly arranged on the outer peripheral side.
[0073]
When the damping mechanism 39 is arranged as in the first embodiment in this way, the suppression effect works effectively not only for the rocking vibration described above but also for the horizontal torsional vibration on the same principle. .
In the first embodiment, the damping capacity of one of the damping mechanisms 39 is changed in order to increase the damping capacity per unit area on the outer peripheral side of the structure 3. However, the damping mechanisms attached to each place are changed. The same effect can be obtained by increasing or decreasing the number of 39.
[0074]
From the above, by appropriately arranging the damping mechanism 39 between the foundation 2 and the structure 3, the torsional vibration, which is the rotational vibration about the vertical axis with respect to the horizontal plane of the structure 3 excited by the horizontal earthquake, is obtained. Can be attenuated.
Further, since the damping force against the rotational vibration of the structure 3 around the horizontal axis, that is, the rocking vibration, can be made larger than when the damping capacity is evenly arranged, the torsional vibration and the rocking vibration of the structure 3 can be obtained. Such a complex vibration is effectively suppressed, and a good three-dimensional seismic isolation effect is obtained in the vertical and horizontal directions.
[0075]
As shown in the configuration diagram of FIG. 3 and the partially cut-away enlarged front view of FIG. 4, the seismic isolation device 40 is provided between the foundation 2 and the flat base 6 in the horizontal direction. The support body 10 and the damping mechanism 41 acting on the second member are arranged. The support 10 uses a laminated rubber or the like, and the damping mechanism 41 uses a steel rod damper or the like as an elastic-plastic damper.
[0076]
Further, a coil spring or the like is provided between the gantry 6 and the structure 3 as an elastic body 38 acting in the vertical direction to support the structure 3. Further, a guide mechanism 43 is inserted between the side surface of the gantry 6 and the side surface of the structure support wall 42.
The guide mechanism 43 regulates the horizontal movement of the structure 3 and guides the structure 3 so as to be freely movable in the vertical direction. Further, a damping mechanism 44 acting in the vertical direction is provided between the gantry 6 and the structure 3.
[0077]
Note that an oil damper, an elasto-plastic damper, or the like is used for the damping mechanism 44, and the damping capacity of the damping mechanisms 44 on both sides is selected to be large in order to enhance the effect of suppressing the rocking vibration of the structure 3.
Although this seismic isolation device 40 is used alone, in order to perform seismic isolation of a large structure 3, a plurality of seismic isolation devices are installed below the structure 3 as shown in FIG. Can be obtained.
[0078]
In this case, in order to enhance the effect of suppressing the rocking vibration of the structure 3, the vertical damping mechanism 44 of each seismic isolation device 40 reduces the damping capacity per unit area of the lower surface of the structure 3 by the lower surface of the structure 3. They are arranged unevenly so as to be larger in the outer peripheral area than in the inner area.
[0079]
Similarly, the horizontal damping mechanism 41 for enhancing the effect of suppressing the torsional vibration of the structure 3 is configured such that the damping capacity per unit area on the lower surface of the structure 3 is smaller on the lower surface of the structure 3 than on the inner region in the outer region. It is arranged unevenly to be larger. Thereby, the structure 3 can obtain a better seismic isolation effect.
[0080]
The third embodiment relates to claim 2 and is a modification of the second embodiment, and as shown in the partially cutaway configuration diagram of FIG. 5, the seismic isolation device 45 includes the base 2 and the gantry 6 having walls on both sides. The supporting body 10 which acts in the horizontal direction and the damping mechanism 41 are arranged between them. The strut body 10 is made of laminated rubber, and the damping mechanism 41 is made of a steel rod damper as an elastic-plastic damper.
Further, the structure 3 is supported by inserting an elastic body 38 acting in the vertical direction between the gantry 6 and the structure 3. Further, the guide mechanism 43 is inserted between the side wall of the gantry 6 and both side walls of the structure 3.
[0081]
The guide mechanism 43 regulates the horizontal movement of the structure 3 and guides the structure 3 so as to be movable in the vertical direction. The guide mechanism 43 may be one in which laminated rubber is placed horizontally.
Further, a damping mechanism 44 is provided between the gantry 6 and the structure 3 so as to work in the vertical direction in parallel with the elastic body 38. Note that an oil damper, an elastic-plastic damper, or the like is used as the damping mechanism 44.
[0082]
In order to enhance the effect of suppressing the rocking vibration of the structure 3, the damping mechanism 44 has a larger damping capacity per unit area on the lower surface of the structure 3 on the lower surface of the structure 3 in the outer peripheral region than in the inner region. It is arranged so as to be uneven.
[0083]
As an effect of the above configuration, the horizontal seismic force transmitted to the gantry 6 is reduced by the horizontal support 10 and the damping mechanism 41 disposed on the foundation 2 at the time of a large earthquake. Horizontal vibration is reduced.
Further, the damping mechanism 41 for the horizontal direction is unevenly arranged so that the damping capacity per unit area on the lower surface of the structure 3 is larger on the lower surface of the structure 3 than on the inner region on the lower surface of the structure 3. As a result, the rotational damping force against torsion increases, and the effect of suppressing the torsional vibration of the structure 3 can be increased.
[0084]
Further, the guide mechanism 43 inserted between the gantry 6 and the structure 3 restrains the relative displacement of the gantry 6 and the structure 3 in the horizontal direction and smoothes the vertical movement. Further, the elastic body 38 and the damping mechanism 44 acting on the gantry 6 and acting in the vertical direction reduce the vertical seismic force transmitted to the structure 3 via the gantry 6.
[0085]
The damping mechanism 44 is unevenly arranged so that the damping capacity per unit area on the lower surface of the structure 3 is larger on the lower surface of the structure 3 in the outer peripheral region than in the inner region. As compared with the case where 44 are evenly arranged, the damping efficiency against the rocking vibration is increased, and the rocking vibration and the complex coupled vibration are efficiently suppressed.
[0086]
Therefore, the horizontal and vertical movements of the structure 3 with respect to the structure 3 at the time of the large earthquake and the coupled vibration such as the rocking vibration can be minimized, and the damping force of the structure 3 against the rocking vibration and the torsional vibration can be increased. Therefore, each vibration is efficiently suppressed and a good three-dimensional seismic isolation performance is exhibited.
[0087]
Fourth embodiment At As shown in the partially cut-away configuration diagram of FIG. 6, the seismic isolation device 46 includes a support 10 acting horizontally and a damping mechanism 41 disposed between the foundation 2 and the lower part of the floating container chamber 47. The support 10 is made of laminated rubber, and the damping mechanism 41 is made of a steel rod damper as an elastic-plastic damper.
[0088]
The floating body housing chamber 47 houses the structure 3 to be subjected to seismic isolation, and is filled with a liquid 48 such as water between the structure 3 and the liquid 48, which exerts buoyancy on the structure 3. . In addition, the elastic body 38 acting vertically and the damping mechanism 44 are interposed between the lower part of the structure 3 and the floating body accommodating chamber 47 to support the structure 3 in the vertical direction and to seismically isolate the vertical direction. Perform
[0089]
A guide mechanism 43 is interposed between the side surface of the structure 3 and the side surface of the floating body storage chamber 47 to regulate the horizontal movement of the structure 3 and guide the structure 3 so as to be movable vertically. The elastic body 38 uses a coil spring, the damping mechanism 44 uses an oil damper or an elasto-plastic damper, and the guide mechanism 43 uses a laminated rubber or a shear key structure.
[0090]
Further, the damping mechanisms 41 and 44 are provided on the lower surface of the structure 3 and the lower surface of the floating body housing chamber 47 per unit area in order to enhance the damping suppression effect against the rocking vibration of the structure 3 and the torsional vibration of the floating body housing chamber 47, respectively. The damping capacity is unevenly arranged so as to be larger in the outer peripheral area than in the inner area on the lower surface of the structure 3.
[0091]
As an effect of the above configuration, in the event of a large earthquake, the horizontal seismic force transmitted to the floating body storage chamber 47 is suppressed by the horizontally acting support 10 and the damping mechanism 41 disposed on the foundation 2. The horizontal vibration of the structure 3 that excites the rocking vibration is reduced.
[0092]
Also, the horizontal damping mechanism 41 is unequally arranged so that the attenuation capacity per unit area on the lower surface of the floating body housing chamber 47 is larger on the lower surface of the floating body housing chamber 47 in the outer peripheral region than in the inner region. Therefore, the rotational damping force against torsion increases, and the effect of suppressing the torsional vibration of the structure 3 increases.
[0093]
Further, the guide mechanism 43 interposed between the floating body housing chamber 47 and the side surface of the structure 3 restrains the horizontal relative displacement between the floating body housing chamber 47 and the structure 3 and smoothly moves up and down. To In addition, the vertically acting elastic body 38 and the damping mechanism 44 disposed on the floating body accommodating chamber 47 reduce the vertical seismic force transmitted to the structure 3.
[0094]
The damping mechanism 44 is unevenly arranged so that the damping capacity per unit area on the lower surface of the structure 3 is larger on the lower surface of the structure 3 in the outer peripheral region than in the inner region. The damping efficiency with respect to the rocking vibration is increased as compared with the case where the 44 is evenly arranged, and the rocking vibration and the complex coupled vibration are efficiently suppressed.
[0095]
Further, since the structure 3 is made to float in the liquid 48 in the floating body accommodating chamber 47, a part of the weight of the structure 3 can be shared by buoyancy. The initial load is not applied to the elastic body 38 acting in the vertical direction, and the allowable deformation amount has a margin, so that the seismic isolation effect can be exerted even for a larger earthquake motion.
[0096]
For example, in order to increase the seismic isolation effect in the vertical direction, it is necessary to make the elastic body 38 soft so that the natural frequency of the structure 3 is about 1 to 1.5 Hz. In this case, the initial subduction displacement is about 0.25 m at 1 Hz and about 0.11 m at 1.5 Hz due to the weight of the structure 3, which is an excessive initial load for the elastic body 38.
[0097]
However, in the third embodiment, since the initial load due to the own weight of the structure 3 is borne by the buoyancy of the liquid 48, only the fluctuating load due to the earthquake acts on the elastic body 38 acting in the vertical direction. The elastic body 38 can cope with even larger seismic motion, and also has an increased strength and safety.
Further, when the structure 3 moves vertically in the liquid 48 during the earthquake, the fluid damping force acts on the structure 3, so that the effect of suppressing the vibration in the vertical direction is further improved, whereby the structure 3 Good three-dimensional seismic isolation is obtained.
[0098]
Fifth embodiment At As shown in the partially cut-away configuration diagram of FIG. 7, the seismic isolation device 49 has a support 10 and a damping mechanism 41 acting in the horizontal direction between the foundation 2 and the first gantry 50 having side walls. . The support 10 is made of laminated rubber or the like, and the damping mechanism 41 uses a steel rod or the like as an elastic-plastic damper.
Also, a plurality of continuous spring wires 52 are suspended via pulleys 51 fixed to opposite ends of the upper side surface of the first gantry 50. The spring wire 52 may be a long continuous line.
[0099]
Further, a second gantry 54 is supported on the spring wire 52 via at least two pulleys 53 at both ends, and the structure 3 is installed on the second gantry 54. Further, a guide mechanism 43 is provided between the side wall of the first gantry 50 and the second gantry 54 so as to allow movement only in the vertical direction and restrict horizontal movement.
[0100]
According to the above configuration, the second base 54 is displaced in the vertical direction to increase elasticity due to the horizontal expansion and contraction of the spring wire 52 stretched between the pulleys 53 of the second base 54 on which the structure 3 is installed. Will have.
Further, the guide mechanism 43 for restraining the relative movement in the horizontal direction inserted between the side wall of the first gantry 50 and the second gantry 54 makes the vertical movement of the second gantry 54 smooth. ing.
[0101]
Therefore, by allowing the structure 3 mounted on the second gantry 54 to independently perform horizontal and vertical seismic isolation, good three-dimensional seismic isolation performance can be obtained.
That is, the horizontal seismic force transmitted to the structure 3 is reduced by the horizontally acting support 10 disposed on the foundation 2, and the spring wire 52 fixed to the first gantry 50 is elastically deformed by expansion and contraction. The vertical seismic force transmitted to the second gantry 54 is absorbed.
[0102]
Further, the guide mechanism 43 inserted between the first frame 50 and the second frame 54 makes the vertical movement of the second frame 54 and the structure 3 smooth, and the first frame 50 And the second base 54 are regulated in relative horizontal movement.
The spring wire 52 exerts a pulling force in the horizontal direction at the lower portion of the second gantry 54, and the pulling pulleys 51 and 53 convert the pulling force into a vertical force. This structure can be used in a tensioned state which is most suitable for strength against deformation of the spring wire 52.
[0103]
In addition, the spring wire 52 can be sufficiently deformed against the force of its own weight of the second base 54 and the structure 3 loaded thereon, so that the elasticity in the vertical direction is set to be small. Since the natural frequency of the structure 3 can be reduced, a greater seismic isolation effect in the vertical direction can be obtained as compared with the elastic body 38 used in the compression direction.
[0104]
8 shows a first modification of the fifth embodiment. In order to obtain a damping force in the vertical direction, a damping mechanism that acts in the direction of expansion and contraction of the spring wire 52 in parallel with the spring wire 52 is shown. 44a.
[0105]
9 shows a second modification of the fifth embodiment, in which one end of a spring wire 52 is fixed to the center of the first gantry 50, and The other end is fixed to the second gantry 54 via the attached pulleys 51, 51, and the second gantry 54 is hung.
Thus, since the second frame 54 is provided with elasticity in the vertical direction, the movement of the spring wire 52 is only the expansion and contraction of the spring with respect to the vertical motion of the second frame 54. Therefore, good three-dimensional seismic isolation performance can be exhibited.
[0106]
Sixth embodiment At As shown in the partial cut-away configuration diagram of FIG. 10, the seismic isolation device 55 suspends the intermediate mount 59 by a wire 58 from the upper mount 57 extending over the opening of the pit 56 formed by excavating the ground 1. Further, the structure 3 is suspended from the lower surface of the intermediate mount 59 by springs 60 for vertical seismic isolation.
[0107]
The operation according to the above configuration has a pendulum structure by suspending the structure 3 on the intermediate mount 59 with the wire 58. Therefore, by adjusting the length of the wire 58, the vibration frequency of the pendulum is set lower than the dominant frequency component of the seismic response at the upper pedestal 57, and the horizontal seismic response at the upper pedestal 57 is reduced. In comparison, the horizontal acceleration response at the structure 3 can be reduced.
[0108]
As for the vertical seismic response, the upper pedestal 57 and the intermediate pedestal 59 perform almost the same movement, but the lower surface of the intermediate pedestal 59 and the structure 3 are separated by a spring 60 for vertical seismic isolation. Vertical acceleration response can be reduced.
[0109]
Seventh embodiment Is the In a modified example of the sixth embodiment, the seismic isolation device 61 suspends an intermediate mount 59 by a wire 58 from an upper mount 57 extending over the opening of the pit 56 as shown in a partially cutaway configuration diagram of FIG. At this time, the structure 3 is installed on the intermediate mount 59 via the vertical seismic isolation spring 62.
[0110]
The operation according to the above configuration has a seismic isolation effect in the horizontal direction since the intermediate mount 59 has a pendulum structure as in the sixth embodiment. In particular, it is necessary to lengthen the wire 58 in order to increase the seismic isolation effect.
[0111]
Even when the vertical space for the pendulum action is not large, the vertical space can be used more effectively by installing the structure 3 on the intermediate mount 59 as compared with the sixth embodiment. be able to.
The vertical acceleration response of the structure 3 can be reduced by the vertical seismic isolation spring 62 inserted between the upper surface of the intermediate mount 59 and the structure 3.
[0112]
Eighth embodiment Is the In another modified example of the sixth embodiment, a seismic isolation device 63 shown in a partially cut-away configuration diagram of FIG. Is connected to a wire 58 at one end.
[0113]
The other end of the horizontally movable wire 58 is fixed to an intermediate gantry 59 in the pit 56 via a pulley 66 attached to the upper gantry 64, and the intermediate gantry 59 on which the structural part 3 is installed is hung. Further, in the pit 56, a part or the whole of the intermediate frame 59 and the structure 3 is submerged in the liquid 48.
[0114]
As the operation of the above structure, the seismic isolation device 63 has a pendulum structure as in the sixth embodiment, and thus has a seismic isolation effect in the horizontal direction.
In the vertical direction, springs 65 having the same rigidity attached to the left and right from the center of the upper frame 64 work, and the vertical vibration of the upper frame 64 is isolated by the spring 65 and applied to the structure 3. Is entered.
[0115]
Further, since part or all of the intermediate frame 59 and the structure 3 are in the liquid 48, buoyancy is generated in the intermediate frame 59 and the structure 3, and the intermediate frame 59 constantly applied to the spring 65 and the wire 58 The tensile load due to the weight of the structure 3 is reduced.
Further, since the intermediate gantry 59 and the structure 3 vibrate in the liquid 48, the apparent mass of the dynamic intermediate gantry 59 and the structure 3 increases due to the additional mass effect. For this reason, under the same conditions, the frequency can be made lower than that in the space, so that there is an effect that the same natural frequency can be realized with a short wire 58 length.
[0116]
Ninth embodiment At The seismic isolation device 67 shown in the configuration diagram of FIG. 13 is inserted between the foundation 2 and the structure 3 and has rigidity K attached at both ends to the foundation 2 and the structure 3. ₀ And a lower end thereof contacts the foundation 2 at rest on both sides thereof.
The upper end has a rigidity K arranged with a gap δ with the structure 3. ₁ Are installed, and a plurality of such sets are appropriately arranged between the foundation 2 and the structure 3 so that the weight of the structure 3 can be equally received.
[0117]
The operation of the above configuration will be described. The characteristic curve diagram of FIG. 14 shows the load and displacement characteristics of the combination of the springs 68 to 70 in the seismic isolation device 67, and the combination of these springs is one set.
Rigidity K installed between foundation 2 and structure 3 ₀ The spring 68 having the function as a vertical seismic isolation spring below the gap δ. Therefore, when the structure 3 is rocked, a large vertical displacement occurs at both ends, and there is a possibility that the structure 3 exceeds the lower gap δ.
[0118]
Here, assuming that a displacement occurs downward at one end of the structure 3 due to the rocking, the rigidity K exceeds the gap δ. ₀ When the spring 68 having compression is subjected to compression, the rigidity K ₁ The upper and lower springs 69 and 70 having the function also start working as springs. By the combination of these springs 68 to 70, K ₀ + 2K ₁ Will have the rigidity.
This is the rigidity K within the gap δ. ₀ , The displacement is smaller than the same load. That is, sinking due to locking of the structure 3 at this point is restricted.
[0119]
In addition to the rocking, even when the springs 69 and 70 sink below the gap δ due to the input of a large earthquake, the rigidity K within the gap δ does not increase. ₀ K compared to ₀ + 2K ₁ It becomes large rigidity. This will limit greater subduction.
[0120]
The gap δ is determined by the demand or rigidity K of the structure 3 side. ₀ If the smaller one of the stress requirements of the spring 68 is set with some margin, the sinking is limited only slightly beyond the gap δ. The stress requirement of 68 will be satisfied.
[0121]
10th embodiment Is above In a modification of the ninth embodiment, a seismic isolation device 71 shown in the configuration diagram of FIG. 15 has a rigidity K having both ends attached to the foundation 2 and the structure 3 between the foundation 2 and the structure 3. ₀ Is provided.
Further, when stationary, the lower end is in contact with the foundation 2, and the upper end is rigid 2K disposed close to the spring 68 via the stopper 72 of the gap δ in both the upper and lower directions with the structure 3. ₁ Are provided, and a plurality of such sets are provided between the foundation 2 and the structure 3 so as to receive the weight of the structure 3 evenly.
[0122]
Next, the operation of the above configuration will be described. The characteristic curve diagram of FIG. 16 shows the load and displacement characteristics of a combination of the springs 68 and 70 and the stopper 72 in the seismic isolation device 71 as one set.
[0123]
The rigidity K installed between the foundation 2 and the structure 3 as in the ninth embodiment. ₀ The spring 68 having the function as a vertical seismic isolation spring within the gap δ. However, the gap δ in the tenth embodiment is equal to the rigidity K. ₀ Of the stopper 72 having a gap δ in the vertical direction, which is arranged in a set with the spring 68 having
Thus, not only the gap δ is provided on the lower side, but also the gap δ is provided on the upper side.
[0124]
The details of the combination of each of the springs 68 and 73 and the stopper 72 are shown in the enlarged partial configuration view of FIG. When the structure 3 is stationary, the rigidity is 2K. ₁ The upper end of the spring 73 having the position is located at the middle point of the gantry 74 attached to the lower surface of the structure 3 in the stopper 72 and does not contact any of the upper and lower parts.
[0125]
At this time, in the stopper 72, the distance between the upper end of the spring 73, the lower surface of the structure 3, and the end of the gantry 74 is set to the gap δ. When the structure 3 vibrates in the vertical direction within the range of ± δ, no contact occurs between the stopper 72 and the tip of the structure 3 and the gantry 74, and thus the spring 73 does not work.
[0126]
Here, when the structure 3 causes a displacement of ± δ or more in the vertical direction, the stopper 72 comes into contact with the structure 3 or the tip of the gantry 74, and the spring 73 starts working. At this time, the rigidity of these sets formed by the two springs 68 and 73 is K ₀ + 2K ₁ become.
Further, when the structure 3 is rocked, a large vertical displacement occurs at both ends thereof, and there is a possibility that the structure 3 exceeds the gap δ. Here, it is assumed that a displacement occurs at one end of the structure 3 downward due to the rocking. At this time, of course, the other end of the structure 3 is displaced upward.
[0127]
When both the lower and upper sides are within the gap δ, the rigidity is K ₀ The seismic isolation function of the spring 68 works. Next, when only the lower side sinks beyond the gap δ, ₀ + 2K ₁ The spring stiffness of this will limit this sinking.
When only the upper side rises beyond the gap δ, K ₀ + 2K ₁ Spring rigidity, and the lifting is limited.
[0128]
Further, when the lower side sinks beyond the gap δ and the upper side rises beyond the gap δ, K ₀ + 2K ₁ Stiffness, and sinking and lifting are limited. At this time, the rigidity K within the gap δ ₀ , The displacement is smaller than the same load.
That is, sinking or lifting due to the locking of the structure 3 is restricted.
[0129]
In addition to the rocking, even when the set of a plurality of springs sinks or lifts over the gap δ due to a large seismic input, the rigidity K within the gap δ does not increase. ₀ Compared to K ₀ + 2K ₁ These limits the greater sinking or lifting at these points.
[0130]
Therefore, the gap δ is required on the structure 3 side or the rigidity K ₀ Of the requirements on the stress of the spring 68 having the following, if the smaller one is set with some margin, the sinking or lifting slightly exceeding the gap δ is limited. Side requirement and rigidity K ₀ The stress requirements of the spring 68 with are satisfied.
[0131]
Eleventh embodiment At The seismic isolation device 75 shown in the configuration diagram of FIG. 18 has a rigidity K between the foundation 2 and the structure 3 with both ends attached to the foundation 2 and the structure 3. ₀ And a rigidity K set to receive a tensile load at rest ₁ Is installed together with the stopper 72a, and a plurality of such sets are appropriately arranged between the foundation 2 and the structure 3 so that the weight of the structure 3 can be equally received.
[0132]
The operation of the above configuration will be described. The partially cut-away enlarged configuration diagram of FIG. 19 shows details of one set in which the springs 68 and 69 and the stopper 72a are combined. Plates 76 and 77 are respectively attached to both ends of the spring 69, and a pedestal 78 attached from the foundation 2 is in contact with the outside of each of the plates 79 and 80 provided at the intermediate portion.
[0133]
The distance between the plates 79 and 80 is made longer than the unloaded length of the spring 69, so that the tension load F is applied to the spring 69 at rest. _T Is working. A column 83 having two projections 81 and 82 at the center and the tip in the vertical direction is attached to the structure 3. The projection 81 is located below the plate 76, and the projection 82 is located on the plate 76. 77 and is in contact with the upper side.
[0134]
The load and displacement caused by the combination of the springs 68, 69 and the stopper 72a configured as described above are shown in the characteristic curve diagram of FIG. For example, it is assumed that the structure 3 moves upward relative to the foundation 2 due to a vertical earthquake input.
When the vertical earthquake input is small, the force pulling the spring 69 is F _T In the following cases, the length of the spring 69 does not change, and the distance between the structure 3 and the foundation 2 does not change from that at rest.
[0135]
However, when the earthquake input becomes large, the force pulling the spring 69 becomes F _T Is exceeded, the projection 81 raises the plate 76 to exceed the tensile force of the spring 69, so that the spring 69 functions.
At this time, the rigidity of the combination of the springs 68 and 69 is K ₀ + K ₁ It becomes. The same applies to the case where the structure 3 moves relatively downward with respect to the foundation 2, and the tension F _T Does not act as a spring until _T Crosses K ₀ + K ₁ Acts as a spring with rigidity.
[0136]
Therefore, when the earthquake input is small, the seismic isolation spring 68 does not operate, and only when the earthquake input is large, the spring 68 operates to exhibit efficient seismic isolation performance. That is, when the seismic isolation device 75 operates for a small earthquake input, the response acceleration of the structure 3 becomes smaller than the input acceleration, but is not so reduced because it is originally small.
[0137]
On the other hand, the displacement is amplified by the operation of the seismic isolation device 75, and if the acceleration is not so reduced, only the disadvantage of increasing the displacement becomes a problem. Therefore, at the time of a small earthquake input in which the response does not exceed the set displacement, an effective seismic isolation effect can be exhibited by disabling the seismic isolation function of the seismic isolation device 75.
[0138]
Twelfth embodiment At As shown in the partial cut-away configuration diagram of FIG. Place 87.
[0139]
Further, one or a plurality of springs 88 each having a spring rigidity K are inserted between the base 2 and the flat plate 85, between the flat plate 85 and the base 87, and between the base 87 and the lower surface of the structure 3. .
The types of the springs 88 include metal springs such as coil springs and disc springs, as well as air springs, rubber blocks, and the like. Any type that can control displacement and load characteristics and has characteristics as a spring is used. Just fine.
[0140]
When the structure 3 moves, for example, downward by δ, the n springs 88 having the spring stiffness K placed between the foundation 2 and the flat plate 85 are compressed and their reaction force is increased. To push up the structure 3 with a force of Kδ per piece.
Further, the p springs 88 having a spring rigidity K placed between the flat plate 85 and the gantry 87 receive tension and try to push up the structure 3 with a reaction force of Kδ per piece.
[0141]
Further, the q springs 88 having the spring rigidity K placed between the gantry 87 and the lower surface of the structure 3 receive compression and try to push up the structure 3 with a reaction force of Kδ per piece. . That is, (n + p + q) springs 88 having rigidity K have the same effect as being in parallel in one layer between the structure 3 and the foundation 2.
[0142]
By arranging the parallel springs 88 in multiple layers in the vertical direction, it is possible to reduce the area for arranging the vertical seismic isolation springs as compared with the case where the parallel springs 88 are arranged in one layer.
In addition, the unitization of the vertical seismic isolation spring with a multi-layer structure can greatly reduce the number of units, making it easier to perform the vertical alignment when installing each unit and improving workability. Is improved.
[0143]
13th embodiment Is the In a modification of the twelfth embodiment, a seismic isolation device 89 shown in a partially cutaway configuration diagram in FIG. 22 projects a support 91 having an intermediate portion and a tip connected to a plurality of flat plates 90 from the lower surface of the structure 3. A gantry 92 having a structure surrounding the flat plate 90 and fixed to the foundation 2 is arranged.
One or more springs 88 having a spring rigidity K are inserted between the base 2 and the flat plate 90, between the flat plate 90 and the gantry 92, and further between the flat plate 90 and the lower surface of the structure 3.
[0144]
When the structure 3 moves downward, for example, by δ, n springs 88 having a spring stiffness K placed between the foundation 2 and the flat plate 90 at the tip are compressed, and the structure 3 moves in the opposite direction. An attempt is made to push up the structure 3 with a force of Kδ per piece.
Further, the p springs 88 having the spring rigidity K placed between the flat plate 90 at the front end and the gantry 92 at the lower end receive tension and try to push up the structure 3 with a force of Kδ per piece as a reaction force. .
[0145]
Similarly, q springs 88 have a spring stiffness K that is compressed between the lower frame 92 and the middle plate 90, and have a spring stiffness K that is pulled between the middle plate 90 and the upper frame 92. The r springs 88 and the s springs 88 having a spring stiffness K subjected to compression between the upper gantry 92 and the lower surface of the structure 3 try to push up the structure 3 with a force of Kδ per piece.
[0146]
In other words, the same operation as the case where (n + p + q + r + s) springs 88 having the spring stiffness K are arranged in parallel in one layer between the structure 3 and the foundation 2 is performed. In addition, by arranging the parallel springs 88 in multiple layers in the vertical direction, it is possible to reduce the area in which the springs 88 for vertical seismic isolation are arranged as compared with the case where the parallel springs 88 are arranged in one layer. Become.
[0147]
In addition, since the spring 88 for vertical seismic isolation has a multi-layer structure as a unit, the number of units can be greatly reduced, and vertical positioning when installing each unit is easy, and work efficiency is improved. Is improved.
[0148]
14th embodiment Is the In a modified example of the twelfth embodiment, a seismic isolation device 93 shown in a partially cut-away configuration diagram of FIG. 23 projects a plurality of branched vertical flat plates 94 from the lower surface of the structure 3, and extends to the center and outside of the vertical flat plate 94. The gantry 95 fixed to the foundation 2 is installed vertically.
A support 10 such as a laminated rubber is placed horizontally between the vertical flat plate 94 and the pedestal 95, and one or a plurality of the supports 10 are inserted vertically.
[0149]
The operation according to the above configuration is such that when the structure 3 moves, for example, downward by δ, all supports having a spring stiffness K (δ) disposed between the plurality of vertical flat plates 94 and the gantry 95 fixed to the foundation 2. That is, a load of K (δ) × δ is applied to the body 10.
[0150]
Here, the rigidity K (δ) is not necessarily a straight line having a constant slope in the curve of the load and the displacement of the support 10, but specifies the displacement dependency. At this time, the support 10 tries to push up the structure by K (δ) × δ per piece. As a result, all of the supports 10 placed in a multilayer structure in the vertical direction act as parallel springs.
[0151]
As described above, by arranging the supports 10 in multiple layers in the vertical direction, it is possible to reduce the area in which the supports 10 are arranged as compared with the case where the supports 10 are arranged in one layer.
In addition, by forming a unit in which the support 10 has a multilayer structure, the number of units can be significantly reduced, and the positioning in the vertical direction when each unit is installed is easy, so that work efficiency is improved.
[0152]
15th embodiment At The seismic isolation device 96 shown in the sectional view of FIG. 24 has pistons 99, 100 which move relatively identically at lower ends 97, 98 on both sides of the structure 3, and cylinders 101, 102 containing these. Is set on the foundation 2.
[0153]
Also, a cylinder head side space 103 of the cylinder 101 and a cylinder head opposite space 104 of another cylinder 102, and a cylinder head opposite space 105 of the cylinder 101 and a cylinder head space 106 of another cylinder 102 are respectively piped. Connection is made by 107 and 108, and a liquid 109 which is almost incompressible is sealed inside.
[0154]
According to the operation of the above configuration, if the vertical displacement at the lower ends 97 and 98 is different due to the rocking vibration of the structure 3, the vertical position of the piston 99 and the piston 100 is changed accordingly.
[0155]
For example, when the structure 3 rotates to the left, the position of the piston 99 at the lower end 97 is relatively lower than the position of the piston 100 at the lower end 98. At this time, it is included in the cylinder head side space 103 of the cylinder 101 at the lower end 97, the cylinder head opposite space 104 of the cylinder 102 at the lower end 98, and the pipe 107 connecting these.
[0156]
The compressed liquid 109 exerts a force to move the piston 99 at the lower end 97 upward and to move the piston 100 at the lower end 98 downward. At the same time, the space 105 at the lower end 97 on the side opposite to the cylinder head, the space 106 at the lower end 98 on the cylinder head side, and the liquid 109 contained in the pipe 108 connecting them are expanded.
[0157]
The expanded liquid 109 exerts a force to move the piston 99 at the lower end 97 upward and the piston 100 at the lower end 98 downward.
Accordingly, the piston 99 which has been displaced downward moves upward, while the piston 100 which has been displaced upward is displaced downward and is stabilized at the same displacement. For this reason, the vertical displacement of both ends of the structure 3 directly connected to the pistons 99 and 100 becomes the same, and rocking vibration is prevented.
[0158]
16th embodiment At The seismic isolation device 110 shown in the configuration diagram of FIG. 25 is installed on the foundation 2 while supporting two links of a left link 111 and a right link 112 so as to be freely rotatable at their respective centers, and installing the two links. 111 and 112 are connected to each other at one end on the center side.
[0159]
In this connection on the center side, elliptical holes 113 and 114 formed in the respective links 111 and 112 are overlapped with each other and are stopped by bolts 115 so as not to separate. Further, since the connecting portion has the elliptical holes 113 and 114, there is play, and the connecting portion can be displaced in the vertical direction.
Further, both outer ends 116 and 117 of the left link 111 and the right link 112 are respectively connected to both ends of the structure 3 via a spring 118 and a dashpot 119 of a damping mechanism.
[0160]
As an effect of the above configuration, when the structure 3 attempts to cause rocking vibration and a difference occurs in the vertical displacement at both ends thereof, a force corresponding to the displacement is transmitted through the spring 118 and the dashpot 119, and the two The positions of the left side link 111 and the right side link 112 at both outer ends 116 and 117 are about to change.
[0161]
For example, when the structure 3 rotates to the left as shown by the dotted line in FIG. 25, the left end of the lower surface of the structure 3 is lowered and the right end is raised. At this time, the spring 118 attached to the left end is compressed and tries to push down the outer end 116 of the left link 111.
Further, the spring 118 attached to the right end of the lower surface of the structure 3 receives the tension and tries to pull up the outer end 117 of the right link 112.
[0162]
When the left end of the left link 111 tries to go down, the right end of the left link 111 tries to go up, but at the same time, when the right end of the right link 112 tries to go up, the left end of the right link 112 tries to go down. However, since the right end of the left link 111 and the left end of the right link 112 are connected on the center side, the vertical displacement on the center side is restricted and does not move.
[0163]
For this reason, the outer end 116, which is the left end of the left link 111, is also restrained, thereby restricting the sinking of the left end of the structure 3 via the spring 118 and the dashpot 119. In addition, the outer end 117, which is the right end of the right link 112, is also restrained, so that the right end of the structure 3 is prevented from being lifted up through the spring 118 and the dashpot 119. This limits rocking vibration as a whole.
[0164]
On the other hand, in the case where the structure 3 moves up and down evenly left and right without rotating, for example, assuming a case where the entire structure sinks, the left end of the left link 111 and the right end of the right link 112 are similarly lowered, and both links 111 and 112 are lowered. Is similarly raised, so that the movement of the structure 3 is not restricted.
[0165]
Thereby, the vertical displacement at both ends of the lower surface of the structure 3 becomes the same, and the rocking vibration is restrained. For this reason, large expansion and contraction of the vertical seismic isolation springs at both ends of the lower surface of the structure 3 are restricted, so that a large load can be prevented from being applied to the spring 118, and the stress design of the spring 118 is facilitated. The range of possible spring applications is increased, allowing the use of more economical and reliable springs.
[0166]
【The invention's effect】
According to the present invention described above, a structure installed on a foundation can be subjected to three-dimensional vibration of a structure caused by an earthquake by an elastic body and a damping mechanism acting independently in the horizontal and vertical directions directly or through a mount or the like. Seismically isolated.
In addition, the arrangement of multiple damping mechanisms and the damping capacity are unevenly arranged on the lower surface of the structure so that the damping capacity per unit area is larger in the outer area than in the inner area, and excited by horizontal earthquake The damping force against the torsional vibration and the rocking vibration is increased, and the vibration is effectively suppressed.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a seismic isolation device according to a first embodiment of the present invention.
FIG. 2 is a schematic view showing rocking vibration of the first embodiment according to the present invention.
FIG. 3 is a configuration diagram of a seismic isolation device according to a second embodiment of the present invention.
FIG. 4 is a partially cut-away enlarged front view of a second embodiment according to the present invention.
FIG. 5 is a partially cut-away configuration diagram of a seismic isolation device according to a third embodiment of the present invention.
FIG. 6 is a partially cut-away configuration view of a seismic isolation device according to a fourth embodiment of the present invention.
FIG. 7 is a partially cut-away configuration view of a seismic isolation device according to a fifth embodiment of the present invention.
FIG. 8 is a partially cutaway configuration view showing a first modification of the fifth embodiment according to the present invention.
FIG. 9 is a sectional view showing a main part of a second modification of the fifth embodiment according to the present invention.
FIG. 10 is a partially cut-away configuration diagram of a seismic isolation device of a sixth embodiment according to the present invention.
FIG. 11 is a partially cut-away configuration view of a seismic isolation device according to a seventh embodiment of the present invention.
FIG. 12 is a partially cut-away configuration view of a seismic isolation device according to an eighth embodiment of the present invention.
FIG. 13 is a configuration diagram of a seismic isolation device according to a ninth embodiment of the present invention.
FIG. 14 is a characteristic curve diagram of load and displacement of a ninth embodiment according to the present invention.
FIG. 15 is a configuration diagram of a seismic isolation device of a tenth embodiment according to the present invention.
FIG. 16 is a characteristic curve diagram of a load and a displacement of the tenth embodiment according to the present invention.
FIG. 17 is a partially cut-away enlarged configuration diagram of a tenth embodiment according to the present invention.
FIG. 18 is a configuration diagram of an eleventh embodiment of the seismic isolation device according to the present invention.
FIG. 19 is a partially cut-away enlarged configuration diagram of an eleventh embodiment according to the present invention.
FIG. 20 is a characteristic curve diagram of load and displacement of an eleventh embodiment according to the present invention.
FIG. 21 is a partially cut-away configuration view of a seismic isolation device of a twelfth embodiment according to the present invention.
FIG. 22 is a partially cut-away configuration view of a seismic isolation device of a thirteenth embodiment according to the present invention.
FIG. 23 is a partially cut-away configuration view of a seismic isolation device of a fourteenth embodiment according to the present invention.
FIG. 24 is a configuration sectional view of a seismic isolation device of a fifteenth embodiment according to the present invention.
FIG. 25 is a configuration diagram of a seismic isolation device of a sixteenth embodiment according to the present invention.
FIG. 26 is a partially cut-away configuration view of a conventional first seismic isolation device.
FIG. 27 is a partially cut-away configuration view of a second conventional seismic isolation device.
FIG. 28 is a front view of a first conventional seismic isolation device.
FIG. 29 is a front view of a third conventional seismic isolation device.
FIG. 30 is a front view of a fourth conventional seismic isolation device.
FIG. 31 is a front view of a fifth conventional seismic isolation device.
FIG. 32 is a front view of a sixth conventional seismic isolation device.
FIG. 33 is a partially cutaway front view of a seventh conventional seismic isolation device.
FIG. 34 is a front view of a conventional eighth seismic isolation device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Ground, 2 ... Foundation, 3 ... Structure, 4, 5, 15, 18, 20, 24, 25, 29, 37, 40, 45, 46, 49, 55, 61, 63, 67, 71, 75 , 84, 89, 93, 96, 110 ... seismic isolation device, 6, 74, 78, 87, 92, 95 ... stand, 7 ... seismic isolation mechanism, 8 ... bearing, 9 ... support base, 10, 16 ... support , 11, 17, 38: elastic body, 12: iron plate, 13: upper plate, 14: lower plate, 19, 34: coil spring, 21: support member, 22: rubber film, 23: air spring, 26: disc spring 27 upper guide, 28 lower guide, 30 slide plate, 31 ball bearing, 32 carriage, 33 guide shaft, 35 fixture, 36, 60, 62, 65, 68, 69, 70, 73 , 88, 118 ... spring, 39, 41, 44, 44a ... damping mechanism, 2. Structure support wall 43 Guide mechanism 47 Floating body storage chamber 48, 109 Liquid, 50 First gantry 51, 53 Pulley, 52 Spring wire, 54 Second gantry 56 ... pits, 57, 64 ... upper mount, 58 ... wire, 59 ... intermediate mount, 66 ... pulley, 72, 72a ... stopper, 76, 77, 79, 80 ... plate, 81, 82 ... projection, 83 ... column, 85 , 90 ... flat plate, 86, 91 ... column, 94 ... vertical flat plate, 97, 98 ... lower end, 99, 100 ... piston, 101, 102 ... cylinder, 103, 106 ... cylinder head side space, 104, 105 ... cylinder head Opposite space, 107, 108 ... pipe, 111 ... left link, 112 ... right link, 113, 114 ... hole, 115 ... bolt, 116, 117 ... link outer end, 119 ... Dashpot.

Claims (2)

By inserting between the foundation and the structure to support the structure, the structure by inserting between a plurality of elastic bodies elastically deformed in the horizontal direction and the vertical direction, as in the basic and the structure to support the plurality of damping capacity per unit area of the structure bottom surface is placed unevenly to be larger at the outer region than the inner region in the lower surface of the structure, to attenuate the displacement in the horizontal and vertical directions A seismic isolation device characterized by comprising a damping mechanism. A plurality of pedestals attached to the support and the first damping mechanism installed on the foundation between the foundation and the structure; and a plurality of pedestals arranged between the pedestals and the structure , A guide mechanism that regulates horizontal movement and guides the movable structure in a vertical direction, and supports the structure by interposing between the structural units and the structure on each of the structural units; inside a plurality of elastic body elastically deformed, while supporting the structure and also interposed between the respective frame and the structure, the damping capacity per unit area of the structure bottom surface in the structure lower surface seismic isolation device characterized by consisting placed unevenly to be larger at the outer region than the region, and the plurality of second damping mechanism for damping the vertical displacement.

Images