JP2002138705A - Base isolation structure of building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base isolation structure of a building capable of lenghtening a natural period of an upper structure supported by laminated rubber and preventing large tensile force from acting on the laminated rubber. SOLUTION: The upper structure 12 is supported on a lower structure 14 via the laminated rubber 16. This base isolation structure is provided with an energizing means 24 interposed in the vertical direction between both structures 12 and 14, tilting according to horizontal directional relative displacement of these structures, and increasing the relative displacement. Cable materials 18 for connecting both structures 12 and 14 are tensioned in a plurality along an outer peripheral part of the upper structure 12. The cable materials 18 are set sufficiently long to a horizontal directional allowable relative displacement quantity of both structures 12 and 14. A damper 22 is arranged between both structures 12 and 14 for absorbing horizontal directional relative vibration of these structures. The energizing means 24 is formed as an extensible contractible mechanism 24 for extending and contracting in the shaft direction by compressively interposing a coil spring, and the upper and lower both ends are connected to both structures 12 and 14 via a ball joint 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration isolation structure for a building in which laminated rubber is interposed between an upper structure and a lower structure.

[0002]

2. Description of the Related Art Conventionally, a vibration isolation structure of a building in which a plurality of laminated rubbers are interposed between an upper structure and a lower structure in order to lengthen the vibration period of the upper structure and reduce the vibration. Are known. This laminated rubber is required to exhibit an anti-vibration effect while supporting the upper structure. For this reason,
The laminated rubber requires considerable hardness (rigidity) to stably support the weight of the upper structure, and the natural period of the upper structure achieved by the laminated rubber is the hardness (rigidity).
For about 3 seconds or less.

[0003]

However, some buildings have a natural period exceeding 3 seconds.
In a high-rise building as an example, since the weight of the superstructure is extremely large, it is difficult to set the hardness (rigidity) of the laminated spring that supports it to be low, and even if the superstructure is supported by the laminated rubber, Satisfactory and effective vibration isolation performance cannot be obtained.

[0004] In addition, when a high-rise building interposed with laminated rubber is subjected to a rocking vibration generated during an earthquake or a tilting moment caused by wind force, one side of the high-rise building opposite to the tilting direction of the high-rise building is likely to float. Then, a large tensile force acts on the laminated rubber disposed here, but there is a problem that the laminated rubber has a low proof stress against the tensile force.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is possible to effectively increase the natural period of an upper structure supported by a laminated rubber, and to apply a large tensile force to the laminated rubber. An object of the present invention is to provide a vibration-isolating structure of a building that does not work.

[0006]

In order to achieve the above object, a vibration isolating structure for a building according to the present invention supports an upper structure on a lower structure via a laminated rubber so that a horizontal structure of the upper structure can be provided. In a seismic isolation structure of a building that prolongs the natural period of directional vibrations, it is interposed in a vertical direction between the upper structure and the lower structure, and with the horizontal relative displacement of these two structures, A biasing means for tilting and biasing with a horizontal component force so as to increase the displacement of both structures is provided, and the upper structure and the lower structure are vertically connected to each other to lift the upper structure. And a plurality of cable members that bear the same are arranged along the outer peripheral portion of the upper structure, and the cable material is sufficient for an allowable relative displacement of the upper structure and the lower structure in the horizontal direction. The feature is that it is set to be longer than multiple floor heights .

That is, when the upper structure and the lower structure are relatively displaced in the horizontal direction due to an earthquake or the like, the biasing means interposed in the vertical direction between the upper structure and the lower structure tilts, and the horizontal component force causes Energizes to increase the relative displacement between the two structures, reducing the horizontal rigidity of the vibration-isolating structure and extending the horizontal vibration cycle compared to simply supporting the upper structure with laminated rubber. Is done.

In addition, since the force exerted by the urging means in the direction in which the upper structure is lifted is borne by the cable material, the upper structure does not float in the vertical direction with respect to the lower structure and does not move relative to the lower structure. Further, since the cable material is provided along the outer peripheral portion of the upper structure, the cable material effectively acts on a lifting force to one side of the upper structure caused by rocking vibration or wind force. Therefore, a large tensile force does not act on the laminated rubber interposed between the two structures. In addition, since this cable material is set to be sufficiently long with respect to the allowable relative displacement of the upper structure and the lower structure in the horizontal direction, the same allowable relative displacement in the horizontal direction is shorter than when the cable material is short. In the case of the displacement amount, the angle of the cable member inclined with the relative displacement can be small. That is,
The cable material can allow horizontal relative movement between the upper structure and the lower structure simply by bending slightly at the upper and lower fastening ends, and hinders the so-called vibration isolation performance by increasing the period by the laminated rubber. I will not do it.

Further, it is only necessary to secure a space around the cable material that allows the horizontal displacement of the upper structure and the lower structure, so that the installation area can be reduced as much as possible. In addition, since the structure has a simple structure in which both ends of the cable member are fixed to both the structural members, the cost of members can be greatly reduced. Further, since this cable material is merely stretched by a known means, it can be easily constructed in a short time.

In addition, since a damper for absorbing the horizontal relative vibration is provided between the upper structure and the lower structure, a vibration damping function for absorbing horizontal vibration energy is provided. Vibration having a long period is attenuated by the vibration isolation performance, and horizontal vibration can be effectively suppressed. Further, the urging means is an expansion and contraction mechanism that expands and contracts in the axial direction by compressing and interposing a coil spring. Upper and lower ends of the expansion and contraction mechanism are connected to the upper structure and the lower structure via a universal joint such as a ball joint. And are connected.

That is, since the upper and lower ends of the expansion / contraction mechanism forming the urging means are connected to the upper structure and the lower structure via, for example, ball joints, the expansion / contraction mechanism moves the relative displacement of the two structures in the horizontal direction. Accordingly, it can be smoothly tilted in the direction of displacement. Since the expansion and contraction mechanism is a coil spring that has been compressed and refurbished, it expands in the tilted axial direction, thereby generating a horizontal component force and increasing the horizontal relative displacement between the upper structure and the lower structure. Therefore, the elastic force of the expansion / contraction mechanism can efficiently act in the direction in which the two structures are relatively displaced.

[0012]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a conceptual diagram showing the structure of an embodiment in which the vibration isolation structure of the present invention is applied to a high-rise building.

The high-rise building 10 has a structure of 23 floors above ground and 5 floors below ground, the underground building 14 has a larger area than the above-ground building 12, and the above-ground building 12 has
4 stands inside. The laminated rubber 16 is interposed between the lower end of each column of the above-ground building 12 forming the upper structure and the top of the underground building 14 forming the lower structure, that is, the floor slab 14a on the first floor.

Between the floor slab 14a on the first floor and the floor slab 12c on the second floor, a telescopic mechanism 24 is provided as urging means for urging the floor slabs away from each other.
The telescopic mechanism 24 is configured, for example, as shown in FIG. That is, an upper spring seat 30a and a lower spring seat 32a are integrally formed on an extensible upper rod 30 and a lower rod 32 which are fitted to each other so as to be slidable with their axes aligned. Upper and lower ends are integrally connected to the seats 30a and 32a to provide a coil spring 34 having excellent linear characteristics. The ends of the upper and lower rods 30 and 32 are formed in a spherical shape, and constitute a well-known ball joint (universal joint) 26 together with the joints of the floor slabs 14a and 12c on the first and second floors. The expansion and contraction mechanism 24 has a free length that is sufficiently longer than the interval between the floor slab 14a on the first floor and the floor slab 12c on the second floor, and is arranged vertically in a compressed state. Both ends are the floor slab 14a on the first floor and the floor slab 12 on the second floor.
c and the ball joint 26 respectively.
An extension mechanism 24 is installed to be rotatable about a horizontal axis. The telescopic mechanism 24 in the compressed state is maintained in the shortest state in a stationary state in which no external force is input to the high-rise building 10, and the elastic force acts in the vertical direction. When the high-rise building 10 relatively displaces the ground building 12 and the underground building 14 in the horizontal direction due to an earthquake or the like, the expansion mechanism 2
4 rotates and tilts in response to the relative displacement. At this time, the telescopic mechanism 24 is set so as to be able to extend to restore the free length from the compressed state by the tilted amount. Therefore, the tilted telescopic mechanism 24 generates a component force in the vertical direction and the horizontal direction according to the tilt angle. For this reason, the horizontal component force is increased by the above-ground building 12 and the underground building 14.
And acts to promote the relative displacement in the horizontal direction.

That is, when the above-ground building 12 and the underground building 14 are relatively displaced in the horizontal direction due to an earthquake or the like, the expansion mechanism 24 interposed therebetween smoothly tilts in the direction of the displacement and also moves in the axial direction. It expands and urges to generate a horizontal component force so as to increase the relative displacement between the ground building 12 and the underground building 14, so that the horizontal rigidity of the entire vibration isolation structure is reduced, and the return timing of the ground building 12 is reduced. Can be delayed. Therefore, the vibration cycle is made longer than when the ground building 12 is simply supported by the laminated rubber 16. Here, the urging force is obtained by the coil spring 34, but the present invention is not limited to this, and a disc spring or an air spring may be used.

The above-mentioned building 12 has a floor slab 1 on its third floor.
2a is extended outward. This extended part 12
A plurality of cables 18 arranged at appropriate intervals so as to surround the above-ground building 12 along the outer periphery thereof are vertically penetrated through b and the first floor slab 14 a of the underground building 14. Each cable 18 is stretched in a state where a tensile force is introduced by a known means, and upper and lower ends thereof are fixed to the upper side of the third floor slab 12a and the lower side of the first floor slab 14a by a well-known fixing device 20. Fastened and fixed.

Also, the cable 18 which penetrates the third floor slab 12a, the second floor slab 12c and the first floor slab 14a is similarly fixed inside the outer wall of the building which forms the outer periphery of the ground building 12. Have been. At this time, the second floor slab 12 c is provided with an opening 12 d having a diameter sufficiently larger than the cable 18. Since the opening 12d prevents the cable 18 from hitting the second floor slab 12c due to the horizontal relative displacement between the ground building 12 and the underground building 14, it may be smaller than the assumed maximum value of the allowable relative displacement.

That is, the force acting in the direction in which the ground building 12 is lifted by the telescopic mechanism 24 interposed between the floor slab 14a on the first floor and the floor slab 12c on the second floor is borne by the cable 18; The building 12 does not float up in the vertical direction with respect to the underground building 14 and relatively moves.
Further, since the cable 18 is provided along the outer peripheral portion of the ground building 12, the cable 18 also effectively acts on a lifting force to one side of the ground building 12 due to rocking vibration or the like. Therefore, even if the laminated rubber 16 is interposed between the above-ground building 12 and the underground building 14 to perform horizontal vibration isolation, a large tensile force does not act on the laminated rubber 16.

Further, since the cable 18 has a length corresponding to two floor heights, the above-ground building 12 and the underground building 14
The rigidity with respect to the relative displacement in the horizontal direction is low. That is, when the relative displacement is made by the same displacement in the horizontal direction, the longer the cable, the smaller the inclination angle. Therefore,
The cable 18 can allow horizontal relative movement between the above-ground building 12 and the underground building 14 only by slightly bending the upper and lower fastening ends. For this reason, the cable 18 does not hinder the elastic deformation of the laminated rubber 16 in the horizontal direction, and it is possible to realize a vibration isolation structure in which the natural period of the ground building 12 is made longer.

Further, since the means for preventing the vertical rise of the ground building 12 in the vertical direction is the cable 18, it is only necessary to secure a space around the cable to allow the horizontal displacement between the ground building 12 and the underground building 14. As a result, the installation area can be reduced as much as possible, and the member cost can be significantly reduced. Further, since the cable 18 is merely stretched by a known means, it can be easily constructed in a short time.

Between the above-ground building 12 and the underground building 14, there is provided a damping damper for damping the relative vibration in the horizontal direction. In this embodiment, the two hydraulic dampers 22 are arranged such that their vibration damping directions form 90 degrees in a horizontal plane. Therefore, even if the above-ground building 12 and the underground building 14 vibrate in any direction in the horizontal plane due to an earthquake or the like, the vibration energy can be absorbed by the hydraulic damper and the vibration can be attenuated. It is possible to effectively suppress the vibrated vibration.
Here, a plurality of hydraulic dampers 22 may be provided as long as they are arranged as described above and form a pair, and the damping dampers are not limited to hydraulic dampers.

[0022]

As described above, in the vibration isolating structure of the present invention, the urging means for increasing the horizontal relative displacement between the upper structure and the lower structure is interposed between them. Therefore, the horizontal rigidity of the entire vibration isolation structure can be reduced, and the vibration period is lengthened.

Further, since the force acting in the direction in which the upper structure floats is borne by the cable material, the upper structure does not float, and a large tensile force is applied to the laminated rubber interposed between the two structures. Does not work.

Further, since the cable member can be allowed to move in the horizontal direction between the upper structure and the lower structure only by slightly bending at the fastening ends at the upper and lower ends thereof, the rigidity in the horizontal direction is not increased. Prolongation of the cycle by the laminated rubber, that is, so-called vibration isolation performance is not hindered.

Further, since the upper structure and the lower structure are connected to each other by a cable material to prevent relative displacement in the vertical direction, the installation area can be reduced as much as possible, and the cost of members can be greatly reduced. It can be easily constructed in a short time.

Further, by providing a damper between the upper structure and the lower structure, a vibration having a vibration damping function and having a long period of time can be attenuated to effectively suppress horizontal vibration. .

The expansion and contraction mechanism serving as the urging means can efficiently apply the elastic force in the direction of relative displacement between the two structures.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a structure of an embodiment in which a vibration isolation structure of the present invention is applied to a high-rise building.

FIG. 2 is a sectional view showing the urging means of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 High-rise building 12 Above-ground building (upper structure) 14 Underground building (lower structure) 16 Laminated rubber 18 Cable (cable material) 20 Fixing tool 22 Hydraulic damper (damper) 24 Expansion mechanism (biasing means) 26 Ball joint (free) Fittings)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16F 15/02 F16F 15/02 F 15/04 15/04 A

Claims (3)

[Claims] 1. A vibration isolation structure for a building in which an upper structure is supported on a lower structure via a laminated rubber and a natural period of a horizontal vibration of the upper structure is lengthened. And the lower structure is vertically interposed, tilts with the horizontal relative displacement of these two structures, and is urged by a horizontal component to increase the displacement of both structures. A biasing means is provided, and a plurality of cable members that connect the upper structure and the lower structure in the vertical direction and bear the lifting force of the upper structure are stretched along the outer peripheral portion of the upper structure. A vibration isolation structure for a building, wherein the cable material is set long enough for the allowable relative displacement of the upper structure and the lower structure in the horizontal direction to be equal to or higher than a plurality of floor heights. . 2. Between the upper structure and the lower structure,
2. A vibration isolation structure for a building according to claim 1, further comprising a damper for absorbing these horizontal relative vibrations. 3. The urging means is an expansion and contraction mechanism that expands and contracts in the axial direction by compressing and interposing a coil spring, and upper and lower ends of the expansion and contraction mechanism are freely connected to an upper structure and a lower structure by a ball joint or the like. The vibration isolation device for a building according to claim 1, wherein the vibration isolation device is connected via a joint.