JP4803620B2 - Seismic isolation structure with damping function - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a seismic isolation structure with a damping function in which a damping function is further added to a structure such as an office building, an apartment house, a bridge, or a detached house that has been seismically isolated by a seismic isolation device.
[0002]
[Problems to be solved by the invention]
In structures such as office buildings, apartment houses, bridges or detached houses, seismic isolation structures have been proposed in which seismic isolation devices are interposed between the structures and the foundation. In such a seismic isolation structure, the seismic isolation device lengthens the natural period of the vibration of the structure, avoids the resonance of the structure due to a sudden large earthquake, and prevents the destruction of the structure due to the earthquake.
[0003]
By the way, even in the above-mentioned seismic isolation structure, the structure vibrates in the horizontal direction in the event of an earthquake motion. If the amplitude of this long cycle is large, the structure may be destroyed if it continues for a long time. In particular, office buildings, apartment houses, detached houses, and the like give a great discomfort and anxiety to the residents.
[0004]
In response to such problems, the mass body mounted on the structure is vibrated with a phase difference together with the vibration of the structure, and the seismic isolation structure with a vibration damping function that reduces the vibration of the structure by the vibration of the mass body However, in such a base-isolated structure, in order to mount the mass body on the structure, it is necessary to design the structure to withstand the load of the mass body in addition to its own load. In addition, when such a strongly designed structure is supported on the foundation via the seismic isolation device, there is a possibility that the load bearing performance of the seismic isolation device must be increased.
[0005]
The present invention has been made in view of the above-mentioned points. The object of the present invention is to effectively reduce the vibration of a structure supported via a seismic isolation device. Provided is a seismic isolation structure with a damping function that can dampen vibrations early, and that does not require an increase in load bearing performance of the structure and the base isolation device due to the mass (weight) of the mass body There is.
[0006]
[Means for Solving the Problems]
The seismic isolation structure with a damping function according to the first aspect of the present invention is interposed between the ground and the structure to support the structure and to isolate the horizontal vibration of the structure with respect to the ground. A seismic device, a vibration control means for controlling horizontal vibration of the structure with respect to the ground, and a support base installed and fixed on the ground. The mass body that is supported by the support base so as to be movable in the horizontal direction and the mass body is vibrated in the horizontal direction by elastic expansion and contraction in response to the horizontal vibration of the structure with respect to the support base. The elastic body connected to the structure at one end and the mass body at the other end, and the structural body at one end to absorb vibration energy in response to the horizontal vibration of the mass body with respect to the support base. Vibration energy absorbing means connected to the mass respectively at the other end The support base is adapted to receive the load of the mass body via the lower surface of the mass body and the upper surface of the support base that are in contact with each other, and the mass body has a structure with respect to its horizontal vibration. The object is connected via an elastic body and vibration energy absorbing means, while the support base is connected only through frictional contact between the lower surface of the mass body and the upper surface of the support base.
[0007]
According to the seismic isolation structure of the first aspect, the structure vibrates in the horizontal direction via the seismic isolation device due to the earthquake because the vibration control means for suppressing the horizontal vibration of the structure is provided. However, the vibration of the structure is reduced by the vibration of the mass body of the vibration damping means having a vibration phase different from that, and the vibration energy of the structure is consumed as, for example, heat energy by the vibration energy absorbing means of the vibration damping means. In addition, the vibration of the structure is attenuated at an early stage, and the mass body is supported by the ground so as to be movable in the horizontal direction, so that the load of the mass body is substantially applied to the structure. Therefore, it is not necessary to increase the load bearing performance of the structure and the seismic isolation device due to the mass of the mass body.
[0008]
In the seismic isolation structure with a vibration damping function according to the second aspect of the present invention, in the seismic isolation structure according to the first aspect, each of the upper surface of the support base and the lower surface of the mass body is a low friction surface. The mass bodies are slidably in contact with each other. Thus, the mass bodies are supported on the ground so as to be movable in a horizontal direction via a low friction surface or a rolling friction surface as a reference.
[0009]
According to the seismic isolation structure of the second aspect, as a result of being able to move the mass body in the horizontal direction with little resistance to the ground, the seismic isolation function of the seismic isolation device is not hindered. The structure can be effectively isolated in the event of an earthquake.
[0010]
The mass body in the present invention is supported by the ground. In this case, a support base similar to the foundation is installed and fixed separately from the foundation, and the mass body is grounded through the support base. However, instead of this, a foundation for supporting the structure is installed over the entire lower surface of the structure, and a part of the foundation is used as a support base. The mass body may be supported on the ground via the base, and when such a support base is used, the mass body is grounded by interposing a low friction surface or a rolling friction surface as a reference between the support base and the mass body. It is better to support it so that it can move horizontally. In the seismic isolation structure according to the second aspect, the rolling friction surface as a reference may be embodied using rollers, rollers, balls (spheres), or the like.
[0011]
In each of the first and second seismic isolation structures according to the first and second aspects, the mass body may be a separate body from the structure, but the third aspect of the present invention is a seismic isolation structure with a damping function. Like a thing, it is good also considering the floor member of a structure as a mass body.
[0012]
Damping function seismic isolation structure of the present onset Ming fourth aspect, it is interposed between the foundation and the structure, to support the structure, seismic isolation for seismic isolation of vibrations in the horizontal direction of the structure And a damping means for damping the vibration in the horizontal direction of the structure, wherein the damping means includes a mass body movable in the horizontal direction and a vibration in the horizontal direction of the structure. An elastic body coupled to the mass body so as to vibrate the mass body in a horizontal direction by elastic expansion and contraction in response, and vibration energy absorbing means for absorbing the vibration energy according to the horizontal vibration of the mass body; The floor member of the structure is a mass body.
[0013]
According to the seismic isolation structure of the fourth aspect, the same effect as the seismic isolation structure of the first aspect can be obtained, and the floor member of the structure is a mass body. Similar to the seismic isolation structure of the third aspect, a separate mass body is not particularly required, the number of mounting steps can be omitted, and the cost can be reduced.
[0014]
In the seismic isolation structure according to the fourth aspect, the floor member as the mass body may be supported movably in the horizontal direction on the foundation via a low friction surface or a rolling friction surface. Alternatively, the floor member may be supported by a support member such as a beam or joist of the structure so as to be movable in the horizontal direction.
[0015]
The seismic isolation device includes a laminated rubber in which rigid layers and elastic layers are alternately laminated in the vertical direction, like the seismic isolation structure with a vibration damping function of the fifth aspect of the present invention. Even if it exists, like the seismic isolation structure with a vibration suppression function of the sixth aspect of the present invention, a lower concave surface that is concave upward, an upper concave surface that is concave downward, and these lower concave surface and upper concave surface It may be provided with a rolling element that is interposed between and a rolling element that can roll with respect to the lower concave surface and the upper concave surface, or a sliding body that is slidable with respect to the lower concave surface and the upper concave surface. It is not limited to, and other things may be used. The lower concave surface and the upper concave surface may be a concave groove surface (a bowl-shaped surface). Alternatively, the concave concave surface may be a concave spherical surface. The sliding body can be composed of rollers and rollers, and the upper and lower surfaces have the same radius of curvature as that of the concave groove surface, and the rods with two plates are composed of rod-like members such that the plates are aligned with each other. In the case of a concave spherical surface, the rolling body can be composed of a ball (spherical body), and the sliding body can be composed of a flat member or a columnar member whose upper and lower surfaces have the same radius of curvature as the concave spherical surface.
[0016]
In the present invention, the elastic body preferably includes at least one of a coil spring, an air spring, and a rubber member, like the seismic isolation structure with a vibration damping function of the seventh aspect, In the present invention, the elastic body preferably has one end and the other end, and is connected to the structure at one end and to the mass at the other end. The connection between the one end portion and the other end portion of the elastic body to the structure and the mass body is performed using a spherical joint.
[0017]
The vibration energy absorbing means of the present invention has a cylinder filled with lead and a huge portion inside the cylinder, and penetrates the cylinder, like the seismic isolation structure with a damping function of the eighth aspect. Even if it is equipped with a rod, as in the seismic isolation structure of the ninth aspect, the cylinder is filled with fluid and the inside of this cylinder is defined in two chambers. A piston having an orifice communicating with the two chambers, and a piston rod fixed to the piston and penetrating both ends of the cylinder may be provided. When such vibration energy absorbing means is used, it is preferable that any one of the cylinder and the rod or the piston rod is connected to the structure and the other is connected to the mass body via a spherical joint.
[0018]
At least one of the elastic body and the vibration energy absorbing means is preferably arranged around the mass body like the seismic isolation structure of the tenth aspect of the present invention.
[0019]
In addition, like the seismic isolation structure with a vibration control function of the eleventh aspect of the present invention, the vibration energy absorbing means is configured to frictionally contact the friction sliding surface provided in the structure and the friction sliding surface. You may comprise and comprise the friction sliding surface provided in the mass body.
[0020]
The structure of the present invention is preferably an office building, an apartment house or a bridge like the seismic isolation structure with a vibration damping function of the twelfth aspect, but the present invention is not limited to these, Other structures may be used.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention and its embodiments will be described in more detail with reference to the drawings. The present invention is not limited to these embodiments.
[0022]
1 and 2, the seismic isolation structure 1 with a vibration control function of this example is composed of a concrete foundation 2 fixed on a ground by a pile or the like and a high-rise office building 3 as a structure. The seismic isolation device 4 that is interposed between the office building 3 to support the load in the vertical direction V of the office building 3 and to isolate the vibration in the horizontal direction H of the office building 3, and the horizontal direction H of the office building 3. Mass body 5 having a vibration period T2 that is substantially the same as the vibration period T1 of the office building 3 in the horizontal direction H, preferably about 0.95 times the vibration period T1. Is provided with vibration damping means 6 adapted to vibrate in the horizontal direction H in response to the vibration in the horizontal direction H of the office building 3.
[0023]
The seismic isolation device 4 includes a plurality of laminated rubbers 11 in which rigid layers and elastic layers are alternately laminated in the vertical direction V. Each laminated rubber 11 is fixed to the laminated rubber 11 on the lower surface. The upper surface is fixed to the base 2 via the lower mounting plate 12 and anchor bolts, and the upper surface is fixed to the lower surface 14 of the office building 3 via the upper mounting plate 13 and bolts fixed to the laminated rubber 11. A plurality of the laminated rubbers 11 to which the lower mounting plate 12 and the upper mounting plate 13 are attached are appropriately distributed and arranged on the lower surface 14 of the office building 3 so as to receive the load of the office building 3. Yes.
[0024]
As the seismic isolation device 4, instead of the laminated rubber 11, a downwardly concave surface that is concave upward, for example, a semi-concave spherical surface, an upwardly concave surface that is concave downward, for example, a semi-concave spherical surface, and these lower half-concave It is interposed between the spherical surface and the upper semi-concave spherical surface, and slides on a rolling body such as a sphere capable of rolling with respect to the lower semi-concave spherical surface and the upper semi-concave spherical surface or on the lower semi-concave spherical surface and the upper semi-concave spherical surface. A pendulum type may be used which includes a sliding body having an upper half concave spherical surface and a lower half concave spherical surface having the same curvature radius as the lower half concave spherical surface and the upper half concave spherical surface.
[0025]
The vibration damping means 6 disposed on the lower surface 14 of the office building 3 elastically moves the mass body 5 in response to the vibration of the office building 3 in the horizontal direction H and the mass body 5 that can vibrate in the horizontal direction H. A plurality of coil springs 15 as elastic bodies connected to the mass body 5 so as to vibrate in the horizontal direction H by expansion and contraction, and a plurality that absorbs the vibration energy according to the vibration of the mass body 5 in the horizontal direction H. Vibration energy absorbing means 16.
[0026]
Although two coil springs 15 are shown in FIG. 1, the vibration of the office building 3 due to the earthquake occurs in all directions in the horizontal direction H including the direction parallel to the plane of FIG. Two or more coil springs 15 are arranged around the mass body 5 in the horizontal plane so that the vibration damping means 6 can respond to the vibration of the office building 3 approximately equally. Yes.
[0027]
Each coil spring 15 has one end 22 and the other end 23, and the one end 22 is connected to a connecting member 25 via a spherical joint 24, and the other end 23 is similarly a spherical joint 26. The connecting member 25 is fixed to the lower surface 14 of the office building 3, and thus each coil spring 15 of this example has a lower surface of the office building 3 at one end 22. 14 is connected to the mass body 5 via a spherical joint 26 at the other end 23 via a spherical joint 24 and a connecting member 25, and the work between one end 22 and the other end 23 of each coil spring 15 is performed. The building 3 and the mass body 5 are connected by using spherical joints 24 and 26.
[0028]
As the elastic body, at least one of an air spring and a rubber member may be used instead of or together with the coil spring 15.
[0029]
Although two vibration energy absorbing means 16 are shown in FIG. 1, as in the case of the coil spring 15, the vibration of the office building 3 due to the earthquake is horizontal including the direction parallel to the plane of FIG. The vibration energy absorbing means 16 is provided in the horizontal plane so that the vibration damping means 6 can respond to the vibration of the office building 3 evenly evenly in the direction of H. Two or more are arranged around.
[0030]
Each vibration energy absorbing means 16 has a cylinder 32 filled with lead 31 inside, a huge portion 33 inside the cylinder 32, and a rod 36 penetrating the end surface member 34 and the end surface portion 35 which are both ends of the cylinder 32. And an attachment member 37 fixed to the cylinder 32. The attachment member 37, which is one end of the vibration energy absorbing means 16, is connected to the connection member 25 via the spherical joint 41, and vibration energy is absorbed. The rod 36 protruding from the end face member 34, which is the other end of the absorbing means 16, is connected to the mass body 5 via the spherical joint 42. Thus, the vibration energy absorbing means 16 is connected to the cylinder 32 and the rod 36. In any case, in this example, the cylinder 32 is connected to the office building 3 via the mounting member 37, the spherical joint 41 and the connecting member 25, and the other side. The rods 36 are respectively connected to the mass body 5 via the spherical joint 42, and one end and the other end of the vibration energy absorbing means 16 are connected to the office building 3 and the mass body 5. 42 is used.
[0031]
In the vibration energy absorbing means 16, plastic flow is generated in the lead 31 by the vibration in the horizontal direction H of the rod 36 based on the vibration in the horizontal direction H relative to the office building 3 of the mass body 5. The vibration is reduced and the vibration energy is absorbed.
[0032]
The mass body 5 is separate from the base 2 and is supported by a support base 51 installed and fixed on the ground so as to be movable in the horizontal direction H. The lower surface 52 and the lower surface 52 of the mass body 5 are horizontally aligned. The upper surface 53 of the support base 51 that is slidably in contact with H is a low friction surface. Thus, the mass body 5 moves in the horizontal direction H to the ground via the lower surface 52 and the upper surface 53 and the support base 51. The support base 51 receives the load of the mass body 5 through the lower surface 52 of the mass body 5 and the upper surface 53 of the support base 51 that are in contact with each other. As for the vibration in the horizontal direction H, the office building 3 is connected to the office building 3 via the coil spring 15 and the vibration energy absorbing means 16, while the support base 51 is connected to the lower surface 52 of the mass body 5 and the support base 51. Are connected only through frictional contact with the upper surface 53.
[0033]
As the vibration energy absorbing means 16, as shown in FIG. 3, a cylinder 61 filled with a fluid, preferably a silicon-based liquid, and the inside of the cylinder 61 are defined in two chambers 62 and 63. A piston 65 having an orifice 64 communicating with the chambers 62 and 63, a piston rod 68 passing through the end surface member 66 and the end surface portion 67 that are both ends of the cylinder 61, and the cylinder 61 In this case, for example, the attachment member 69 is connected to the connecting member 25 via the spherical joint 41, and the piston rod 68 is connected to the mass via the spherical joint 42. Each is connected to the body 5.
[0034]
In the vibration energy absorbing means 16 shown in FIG. 3, the orifice 64 is formed in the fluid in the cylinder 61 by the vibration in the horizontal direction H of the piston rod 68 based on the vibration in the horizontal direction H relative to the office building 3 of the mass body 5. This causes the two chambers 62 and 63 to flow in and out, thereby reducing vibration in the horizontal direction H and absorbing vibration energy.
[0035]
In the above seismic isolation structure 1, when the foundation 2 is vibrated in the horizontal direction H due to the earthquake, the laminated rubber 11 is sheared and deformed in the horizontal direction H, and part of the vibration energy in the horizontal direction H of the foundation 2 is office work. When transmitted to the building 3, the office building 3 vibrates in the horizontal direction H with a natural period T1 based on the mass m1 of the office building 3, the spring constant k1 of the laminated rubber 11, the damping coefficient c1, and the like. Due to this vibration of the office building 3, the mass body 5 also has a natural period substantially equal to the natural period T1 based on the mass m2 of the mass body 5, the spring constant k2 of the coil spring 15, the damping coefficient c1 of the vibration energy absorbing means 16, and the like. The vibration of the office building 3 vibrates in the horizontal direction H at T2 with a substantially opposite phase to the vibration phase of the office building 3, and the vibration amplitude of the office building 3 is greatly reduced by this vibration of the mass body 5. Energy is mainly consumed and absorbed as thermal energy in the vibration energy absorbing means 16, and the vibration of the office building 3 is attenuated at an early stage.
[0036]
In the seismic isolation structure 1, since the mass body 5 is supported by the ground so as to be movable in the horizontal direction H, the load of the mass body 5 is not substantially applied to the office building 3. Therefore, the mass body No increase in load bearing performance of the office building 3 and the seismic isolation device 4 due to the mass of 5 is required.
[0037]
In the seismic isolation structure 1, the mass body 5 is supported by the ground so as to be movable in the horizontal direction H via the lower surface 52 and the upper surface 53, which are low friction surfaces. As a result of being able to move in the horizontal direction H without resistance, the seismic isolation function of the seismic isolation device 4 is not hindered, and the office building 3 can be effectively isolated in the event of an earthquake.
[0038]
In the seismic isolation structure 1 described above, the mass body 5 and the vibration energy absorbing means 16 are provided separately from the office building 3, but instead, as shown in FIG. The floor building 71 is a part of the floor, and the vibration energy absorbing means supports the friction surface 72 on the lower peripheral surface of the floor member 71 and the peripheral lower surface of the floor member 71 slidably in the horizontal direction H. 3 and a friction surface 74 that is in frictional contact with the friction surface 72. In this case, one end 22 of the coil spring 15 is attached to the column or wall 75 of the office building 3, The other end portions 23 are connected to the side end surfaces 76 of the floor member 71, respectively.
[0039]
The seismic isolation structure 82 including the damping member 81 provided with the floor member 71 as the mass body, the coil spring 15 as the elastic body, and the friction surfaces 72 and 74 as the vibration energy absorbing means shown in FIG. Similarly to the structure 1, when the office building 3 is vibrated in the horizontal direction H due to an earthquake, the floor member 71 also has the mass m <b> 2 of the floor member 71 and the spring constant of the coil spring 15 due to this vibration of the office building 3. vibrates in the horizontal direction H in a phase substantially opposite to the vibration phase of the office building 3 with a natural period T2 substantially equal to the natural period T1 based on k2 and the damping coefficient c1 caused by the sliding frictional resistance at the friction surfaces 72 and 74. The vibration of the office building 3 is greatly reduced by this vibration of the floor member 71, and the vibration energy of the office building 3 is mainly consumed and absorbed as heat energy at the friction surfaces 72 and 74, and The vibration of the building 3 is attenuated at an early stage.
[0040]
According to the seismic isolation structure 82, since the floor member 71 of the office building 3 is a mass body, the number of mounting steps for the mass body 5 can be omitted, and the cost can be reduced.
[0041]
The vibration control means 81 including the floor member 71 that can vibrate in the horizontal direction H as a mass body is not provided only on the first floor, the intermediate floor, or the basement of the office building 3, and any appropriate plural number It may be provided on all floors if necessary.
[0042]
【The invention's effect】
According to the present invention, the vibration of the structure supported via the seismic isolation device can be effectively reduced, and the vibration can be attenuated at an early stage. In addition, the mass of the mass body It is possible to provide a seismic isolation structure with a damping function that does not require an increase in load bearing performance of the structure and the seismic isolation device due to (weight).
[Brief description of the drawings]
FIG. 1 is a front view of a preferred example of an embodiment of the present invention.
FIG. 2 is a partially enlarged explanatory view of the example shown in FIG.
3 is a cross-sectional view of another example of vibration energy absorbing means applicable to the example shown in FIG.
FIG. 4 is an explanatory diagram of another preferred example of one embodiment of the present invention.
[Explanation of symbols]
1 Seismic isolation structure with damping function 2 Foundation 3 Office building 4 Seismic isolation device 5 Mass 6 Damping means

Claims (7)

A seismic isolation device interposed between the ground and the structure to support the structure and to isolate the horizontal vibration of the structure against the ground, and to control the horizontal vibration of the structure against the ground. Mass comprising a vibration means and a support base installed and fixed on the ground, and the vibration suppression means is in contact with the upper surface of the support base on the lower surface and is supported by the support base so as to be movable in the horizontal direction. The mass body is connected to the structure at one end and the mass body at the other end so that the mass body is vibrated in the horizontal direction by elastic expansion and contraction in response to the horizontal vibration with respect to the body and the support of the structure. An elastic body and vibration energy absorbing means connected to the structure at one end and to the mass at the other end so as to absorb vibration energy in response to horizontal vibration of the mass body with respect to the support base. And the support bases are in mass The mass body receives the load of the mass body through the lower surface of the support and the upper surface of the support base, and the mass body is connected to the structure via the elastic body and the vibration energy absorbing means with respect to the horizontal vibration. On the other hand, the support base is connected only through frictional contact between the lower surface of the mass body and the upper surface of the support base, and each of the upper surface of the support base and the lower surface of the mass body is a low friction surface. The vibration energy absorbing means includes a friction sliding surface provided on the structure and a friction provided on the mass body so as to make frictional contact with the friction sliding surface. A seismic isolation structure with a vibration control function that has a sliding surface and uses the floor of the structure as a mass. The seismic isolation device according to claim 1, wherein the seismic isolation device includes a laminated rubber in which rigid layers and elastic layers are alternately laminated in a vertical direction. The seismic isolation structure with a damping function according to claim 1 or 2, wherein the elastic body includes at least one of a coil spring, an air spring, and a rubber member. 4. The vibration energy absorbing means according to claim 1, further comprising: a cylinder filled with lead; and a rod having a huge portion inside the cylinder and penetrating both ends of the cylinder. The seismic isolation structure with the damping function described. The vibration energy absorbing means includes a cylinder filled with a fluid, a piston having an orifice that communicates the two chambers with each other, and a fixed piston. The seismic isolation structure with a damping function according to any one of claims 1 to 3, further comprising a piston rod penetrating both ends of the cylinder. The seismic isolation structure with a damping function according to any one of claims 1 to 5, wherein at least one of the elastic body and the vibration energy absorbing means is disposed around the mass body. The seismic isolation structure with a damping function according to any one of claims 1 to 6, wherein the structure is an office building, an apartment house, or a bridge.

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