JP4426877B2 - Seismic isolation structure - Google Patents

Description

  The present invention relates to a base-isolated structure that controls environmental vibrations and vibrations caused by earthquakes in normal times.

Conventionally, a structure is composed of a foundation structure and an upper structure built on the foundation structure. When a seismic isolation structure is adopted for this structure, a seismic isolation device such as laminated rubber is used. An upper structure is provided on the foundation structure, and a damper as a damping means is provided between the foundation structure and the upper structure so that vibration energy acting on the upper structure is absorbed by the damper.
In addition, when a plurality of upper structures are adjacent to each other on the foundation structure to form a base isolation structure, a foundation structure (artificial ground) supported via the base isolation device is provided on the base structure, A structure in which a plurality of upper structures are arranged at predetermined intervals on the upper part, or a seismic isolation device is provided at the lower part of each upper structure arranged at predetermined intervals, and each upper structure is independently foundational. It is the structure provided on the structure.
Here, when a conventional seismic isolation structure is configured such that a plurality of adjacent upper structures are independent from each other, adjacent upper structures or first floor parts are connected by a damper, and at the time of an earthquake While preventing collision between upper buildings, the relative deformation between adjacent upper structures is suppressed, and the design of an expansion joint provided in a passage or the like is facilitated. Note that there may be a plurality of positions where the damper is connected at the lower part, the upper part of the upper structure, or a plurality of stages in the vertical direction.
These dampers serve to absorb vibration energy in the horizontal direction of the upper structure, and are installed so as to reduce horizontal vibration of the upper structure and relative deformation between the structures (for example, Patent Document 1). reference).

JP 2001-193111 A (paragraph numbers [0003] to [0029], FIG. 1)

However, when a plurality of superstructures are installed on top of a single base structure (artificial ground) at a predetermined interval, vibrations that occur during normal use (vibrations and weights due to the operation of machines installed in the building) Vibrations associated with the movement and installation of objects, etc., hereinafter referred to as “environmental vibrations”) from one predetermined upper structure through the foundation structure (artificial ground) to the adjacent upper structure There is a problem of propagation through the structure.
In addition, even when a plurality of upper structures are separated from each other to be seismic isolation structures provided on the foundation structure, other adjacent upper parts are connected via dampers that connect the upper structures adjacent to each other with environmental vibration. There is a problem of propagating to structures.

  Therefore, in the present invention, the above-described problems are solved, and propagation of environmental vibrations from adjacent upper structures is prevented in normal times, and the expansion joint is reduced in size by suppressing relative deformation of adjacent upper structures during earthquakes. The purpose is to provide a seismic isolation structure that can be used.

  In order to solve the above problems, a seismic isolation structure of the present invention comprises a foundation structure constructed on the ground, and a plurality of superstructures disposed on the foundation structure via seismic isolation means, The upper structure is composed of a vibration detection means provided on the foundation structure or a ground surface in the vicinity of the foundation structure and a connection or connection between the adjacent upper structures according to the vibration state detected by the vibration detection means. Variable connection means for variably releasing the connection, and the variable connection means releases the connection between the adjacent upper structures in a normal state in order to prevent propagation of environmental vibration from the adjacent upper structure. When the vibration detection means detects an earthquake shake greater than the reference vibration state index value greater than the shake due to environmental vibration, the adjacent upper structures are configured to be connected to each other. And butterflies.

  Here, as described above, the environmental vibration refers to vibration caused by operation of equipment machines installed in a building, vibration due to movement of a car or the like in a building, installation of heavy objects, and the like. Here, there are various shakings of buildings due to environmental vibrations, for example, small shakings that people do not feel much like vibrations caused by air conditioning machines and piping, etc., car movements in parking lots and mechanical parking lot facilities Vibrations that can be felt by humans, such as vibrations that cause troubles in other operations such as vibrations caused by large-scale machine equipment such as centrifuges and rotary presses.

  In the seismic isolation structure of the present invention, the variable connecting means may be a variable damper.

  Further, the seismic isolation structure of the present invention is configured such that when the variable damper is less than the reference vibration state index value with a reference vibration state index value as a threshold, the damping force is set to a lower limit value and is adjacent to the variable vibration damper. In a state where the connection between the upper structures is released and the reference vibration state index value is equal to or higher than the reference vibration state index value, the upper structure may be configured to connect the adjacent upper structures with the damping force set to the upper limit value.

  Thus, when the variable coupling means is less than the reference vibration state index value (normal time), the connection between the adjacent upper structures is released, so that each upper structure is separated from the other upper structures. Propagation of environmental vibrations can be prevented, and in the case of a reference vibration state index value or more (during an earthquake), adjacent upper structures are connected and vibrate almost integrally. The relative displacement of the structure is reduced, and the expansion joint installed between the adjacent upper structures can be prevented from being broken. Thereby, since the relative displacement of the adjacent upper structure becomes small, the expansion joint can be miniaturized.

  In addition, the variable coupling means is a variable damper, and when this variable damper is less than the reference vibration state index value (normal time), the damping force of the variable damper is set to the lower limit value, so that adjacent upper structures The connection between the two is almost released and the influence of environmental vibration on each upper structure from other upper structures can be reduced to prevent propagation of environmental vibration from other adjacent upper structures. If the value is greater than the index value (during an earthquake), the damping force of the variable damper is switched to the upper limit value, so adjacent seismic isolation structures vibrate almost integrally and are installed between adjacent upper structures. The expansion joint can be miniaturized while preventing the expansion joint from being destroyed.

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. It should be noted that the normal time is assumed to be no earthquake.

  FIG. 1 is a side sectional view schematically showing an example of the seismic isolation structure according to the first embodiment of the present invention, FIG. 2 is an enlarged view of a part A in FIG. 1, and FIG. FIG. 4 is a relationship diagram showing the relationship between the connection state of the connecting means and the reference vibration state index value, and FIG. 4 is a relationship diagram showing the relationship between the damping force of the variable damper and the reference vibration state index value.

As shown in FIG. 1, the seismic isolation structure 10 according to the first embodiment of the present invention includes a foundation structure 11, a plurality of upper structures 13, and between the foundation structure 11 and the upper structure 13. It is composed of seismic isolation means 14 composed of laminated rubber bearings arranged, variable connection means 15 for connecting adjacent upper structures 13, 13, and expansion joint 16 provided on adjacent upper structures 13, 13. ing.
The seismic isolation means is not limited to the laminated rubber bearing, and a sliding bearing, a rolling bearing, etc. can be used, or a combination thereof may be used.

  As shown in FIG. 1, the foundation structure 11 is constructed on the ground G as a solid foundation, for example. In addition, the upper structure 13 is provided in a state where the first floor portion is separated from the foundation structure 11 as a base structure 12, and is divided into four in this embodiment, and the adjacent base structures 12, It is arranged on the substructure 11 so as to have a predetermined interval between 12. The seismic isolation means 14, 14... Are arranged on the lower surface of the base structures 12, 12... So as to form a gap between the foundation structure 11 and the base structure 12. The upper structure 13 includes a sensor 17 as vibration detecting means for detecting vibration and a variable connecting means 15. The variable connecting means 15 is a variable damper (hereinafter referred to as “variable damper”), and is provided between the adjacent base structures 12 and 12 so as to connect them. Here, the upper structure 13 positioned on the outer side is formed in a substantially gate shape so as to straddle the two base structures 12, 12 positioned on the inner side. The other upper structures 13 and 13 are provided so as to be located on the inner side so as to be covered by the outer upper structure 13. The expansion joint 16 is provided between the adjacent upper structures 13 and 13.

As shown in FIG. 2, the variable damper 15 includes a damper main body 151 and a control unit 152. When the variable damper 15 is less than the reference vibration state index value, the connection is released and the base structure of the upper structure 13 is formed. This serves to release the connection between the objects 12 and prevent the vibrations from the other upper structures 13, 13... From propagating, and when it exceeds the reference vibration state index value, the base structure of the upper structure 13 It also plays a role of reducing relative displacement between the adjacent upper structures 13 and 13 by connecting the objects 12 together and vibrating them integrally.
In the present embodiment, the reference vibration state index value is a value having a predetermined intensity greater than the vibration due to the environmental vibration. For example, the maximum acceleration due to the environmental vibration is 5 Gal (0.05 m / s ² ). In some cases, an acceleration value larger than that is set as the reference vibration state index value. In this case, if any one value in the range of acceleration 8 Gal (0.08 m / s ² ) to 25 Gal (0.25 m / s ² ) corresponding to vibration having a seismic intensity of about 3 is set as the reference vibration state index value. good.

  As the damper main body 151, a conventionally known oil-type variable damper can be used, and the opening and closing of an oil flow rate control valve (solenoid valve) (not shown) can be opened and closed. The pressure applied to the oil is adjusted by the control means 152 based on vibration state index value data detected by a sensor 17 (described later) installed on the nearby ground G surface to widen or narrow the oil flow range. By changing it, the damping force can be changed.

  For example, when the flow rate adjustment valve of the damper main body 151 is open when it is less than the reference vibration state index value, the pressure applied to the oil of the damper main body 151 is reduced, and the damping force becomes the lower limit value. It has become. Therefore, since the connection state is very weak, vibrations of the base structure 12 and the upper structure 13 are not easily propagated to the adjacent base structures 12 and 12 and the upper structures 13 and 13.

  In addition, when the reference vibration state index value is greater than or equal to the reference vibration state index value, the flow regulating valve of the damper main body 151 is closed, so that the pressure applied to the oil of the damper main body 151 increases, and the load applied to the damper main body 151 increases. It has become. Therefore, the damper main body 151 can reduce the relative displacement between the adjacent foundation structures 12 and 12 by absorbing the vibration with the damping force having an upper limit value. Since the movable range of the expansion joint 16 is limited, the relative displacement at a predetermined interval between the adjacent foundation structures 12 and 12 cannot be increased. Therefore, in the case of the reference vibration state index value or more, the oil pressure is reduced. By connecting with the enlarged damper main body 151, the relative displacement between the adjacent base structures 12, 12 becomes small, and the adjacent base structures 12, 12 vibrate in an almost integrated state. Therefore, destruction of the expansion joint 16 can be prevented.

Here, the sensor 17 is provided in the foundation structure 11 in the present embodiment, and detects the acceleration that is the reference vibration state index value, generates vibration state index value data, and outputs it to the control unit 152. Fulfill.
For example, a conventionally known acceleration sensor can be used as the sensor 17. This acceleration sensor is composed of, for example, a capacitor, a movable silicon substrate, and a spring. When a movable silicon substrate and a spring are arranged inside a capacitor composed of two plates, vibration occurs. The movable silicon substrate biases the spring and displaces its position, so that electricity is stored in the capacitor. The acceleration of the substructure 11 can be detected by converting this electricity (capacitance) into acceleration.
The sensor 17 may be provided on the base structure 12 or the upper structure 13.

As shown in FIGS. 3 and 4, the control means 152 inputs the vibration state index value data output from the sensor 17, and the damper main body 151 so as to be in a connected state corresponding to the vibration state index value data. It plays a role of opening and closing a flow control valve (not shown).
The control means 152 compares the reference vibration state index value preliminarily converted into data, and adjusts the flow rate of the damper main body 151 when the input vibration state index value data is equal to or greater than the preliminarily converted reference vibration state index value. Control to switch the damping force of the damper main body 151 to the upper limit value (see FIG. 4) is performed by adjusting the valve to increase the damping force. Further, when the input vibration state index value data is less than the preliminarily converted reference vibration state index value, the damping force of the damper main body 151 is reduced by adjusting the flow rate control valve of the damper main body 151. Control is performed to set the connecting force of the damper main body 151 to the lower limit value (see FIG. 4).

As a result, when the variable damper 15 is used, the base structures 12 are disconnected from each other when the vibration index is less than the reference vibration state index value (see FIG. 3). Since the object 13 vibrates without being affected by the environmental vibration, it is possible to prevent the environmental vibration from propagating to another adjacent foundation structure 13. Further, when the reference vibration state index value is equal to or greater than the reference vibration state index value, the base structures 12 and 12 are connected to each other (see FIG. 3). Breakage of the expansion joint 16 provided on the objects 12 and 12 can be prevented.
Further, when the variable damper 15 is less than the reference vibration state index value, the damping force of the variable damper 5 is set to the lower limit value, so that propagation of environmental vibration from other adjacent foundation structures 12 and 12 is prevented. Can do. Further, when the value is equal to or greater than the reference vibration state index value, the damping force of the variable damper 15 is switched to the upper limit value, so that the relative displacement between the adjacent upper base structures 12 and 12 is suppressed to be small, and the adjacent upper base structure is connected. This prevents the expansion joint from being destroyed.

As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment. For example, instead of the variable damper 15 being the variable damper 15, for example, a disc brake system 15A can be used.
The disc brake system 15A includes a control unit 152, and includes a disc brake instead of the damper main body 151.
This disc brake is composed of a plate-like disc D1, a brake pad D2, a support portion D3, and a hydraulic jack D4. As shown in FIG. 5 (a), in the plate-like disc D1, the surface held by the brake pad D2 is leveled in the vertical direction and is arranged between the base structures 12, 12, and one end portion Are joined to one adjacent foundation structure. The other end portion faces the other base structure 12. Further, a support body D3 provided with a brake pad D2 is provided on the other base structure 12 via a hydraulic jack D4 so that the disk D1 can be held by oil pressure (not shown). . The oil pressure of the oil is adjusted by controlling a hydraulic jack by a control means 152 described later.
Therefore, as shown in FIG. 5B, when the brake pad D2 holds the disk D1, the adjacent base structures 12 and 12 are connected to each other and vibrate substantially integrally. As shown in (a), when the brake pad D2 releases the disk D1, the adjacent base structures 12, 12 are released from the connected state, and environmental vibrations from other upper structures 13 are not propagated. It is like that. As shown in FIGS. 3 and 4, the control means 152 inputs the vibration state index value data output from the sensor 17, and the hydraulic jack D <b> 4 has a connection state corresponding to the vibration state index value data. Plays a role in controlling hydraulic pressure. Even in this configuration, if the reference vibration state index value is less than the reference vibration state index value, the damping unit 151 can be in a state in which the adjacent foundation structures 12 and 12 are disconnected, and the reference vibration In the case of the state index value or more, the adjacent foundation structures 12 and 12 can be connected to each other.

Further, for example, in the embodiment of the present invention, the sensor 17 is provided in the foundation structure 11, but the position of the sensor 17 is not limited to this, and for example, the ground G plane and the foundation structure in the vicinity of the foundation structure 11. 12, the upper structure 13, the expansion joint 16, the variable damper 15, the seismic isolation means 14, etc. may be provided.
Even if the sensor 17 is provided in this way, it is possible to prevent propagation of vibration between the base structures 12 and 12 and reduce vibration to the upper structures 13, 13.
The sensor 17 detects the acceleration of the foundation structure 11 as the reference vibration state index value, but detects the deformation amount, displacement amount, and displacement speed of the seismic isolation means 14, the variable damper 15, and the expansion joint 16 as the vibration state index. Thus, vibration state index value data may be generated. In this case, a deformation value larger than the vibration due to the environmental vibration is set as the reference vibration state index value. For example, when the maximum deformation due to environmental vibration is 0.1 mm, a larger deformation value may be set as the reference vibration state index value.
In the embodiment of the present invention, the variable damper 15 is provided between the base structures 12, 12. However, the variable damper 15 is provided for the upper structures 13, 13 provided on the base structures 12, 12. It may be provided between the upper structures 13 and 13 to be connected to each other.
The variable damper may be an MR damper using a magnetorheological fluid called a Bingham fluid, an ER damper using an electrorheological fluid (ER), a variable friction damper, or the like.
Moreover, the seismic isolation structure of this invention can be used for various structures, such as a factory, a hospital, a school, a library, a company building. The upper structure may be a single-layer structure or a multi-storey structure.

It is a sectional side view which shows typically an example of the seismic isolation structure which concerns on 1st embodiment of this invention. It is the A section enlarged view of FIG. It is a graph which shows the relationship between the connection state of a variable type connection means, and a reference | standard vibration state index value. It is a graph which shows the relationship between the damping force of a variable type damper, and a reference vibration state index value. It is a modification of a variable type connection means, Comprising: (a) is a schematic diagram which shows the state by which connection was cancelled | released, (b) is a schematic diagram which shows the state connected.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Seismic isolation structure 11 Foundation structure 12 Base structure 13 Upper structure 14 Seismic isolation means 15 Variable damper 151 Damper main-body part 152 Control means 16 Expansion joint 17 Sensor (vibration detection means)
G ground

Claims (3)

A foundation structure constructed on the ground, and a plurality of superstructures disposed on the foundation structure via seismic isolation means,
The upper structure is composed of vibration detection means provided on the foundation structure or a ground surface in the vicinity of the foundation structure, and connection between adjacent upper structures according to the vibration state detected by the vibration detection means. Variable connection means for variably releasing connection,
The variable connection means is set in a state in which the connection between the adjacent upper structures in a normal state is released in order to prevent propagation of environmental vibration from the adjacent upper structure,
The seismic isolation structure is configured to connect adjacent upper structures when the vibration detection unit detects an earthquake shake greater than a reference vibration state index value greater than a shake caused by environmental vibration. object.   The seismic isolation structure according to claim 1, wherein the variable connecting means is a variable damper. The variable damper has a reference vibration state index value as a threshold value,
If it is less than the reference vibration state index value, the damping force is set to the lower limit value and the connection between the adjacent upper structures is released,
The seismic isolation structure according to claim 2, wherein when the reference vibration state index value is equal to or greater than the reference vibration state index value, the damping force is set to an upper limit value and the adjacent upper structures are connected to each other.

Images