JP2004286052A - Vibration damping apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibration damping apparatus which can satisfactorily suppress the response displacement of a structure caused by a strong earthquake in a limited seismic isolation space. <P>SOLUTION: The vibration damping apparatus (1) located between the ground and the structure (100) so as to constitute a seismic isolation system for isolatedly supporting the structure comprises outside disks (50, 51) which are fixed to the ground side so as to horizontally elongate and vertically have a required interval, and inside disks (52) alternately arranged so as to overlap with the outside disks arranged so as to horizontally elongate and vertically have a required interval, and inside cylindrical plates (55, 56) horizontally elongated. The vibration damping apparatus (1) further comprises a moving body (70) which can horizontally slide with respect to the ground side, and outside cylindrical plates (58) fixed to the structure side so as to vertically elongate and overlap with the inside cylindrical plates. Further, fluid having chemically stable viscosity is located between both of the disks and both of the cylindrical plates in order to apply shearing resistance to both of the disks and both of the cylindrical plates, respectively. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a damping device having two-dimensional or three-dimensional degrees of freedom utilizing the shear resistance of a viscous fluid.
[0002]
[Prior art]
Generally, earthquakes occur in three directions of freedom in two directions horizontal to the ground and one direction perpendicular to the ground. Therefore, if a natural spring of a building or the like is lengthened by installing a soft spring below the foundation of the building or the like and the response acceleration of the building or the like to an earthquake is reduced, the inertia force acting on the building becomes small, and the design of the building or the like is reduced. It will be advantageous. At this time, since the response displacement of the building or the like becomes large on the contrary, a damping device for suppressing the displacement is applied. The combination of a soft spring and a damping device is called a seismic isolation device.
[0003]
For small and medium-sized earthquakes, the inertial force acting on buildings and the like is small, so even a small damping device using frictional resistance between metals, etc., can sufficiently suppress the response displacement of the buildings and the like (for example, see Patent Reference 1). On the other hand, for a large earthquake, a method of interposing a viscous fluid between the opposing substrate surfaces and suppressing a response displacement of the building or the like by a large shear resistance force of the viscous fluid is effective.
[0004]
In the conventional seismic isolation method using the shear resistance of a viscous fluid as described above, separate seismic isolation devices are used for horizontal seismic isolation and vertical seismic isolation for the ground. In horizontal seismic isolation, a structure is used in which one resistance plate faces the bottom surface of a viscous fluid container filled with a viscous fluid. In vertical seismic isolation, a piston such as a soft plastic damper or a lead extrusion type damper is used. And a cylinder.
[0005]
[Patent Document 1]
JP 2001-50336 A
[Problems to be solved by the invention]
However, when dealing with a large earthquake, the damping efficiency per installation area of the damping device is reduced only by the shear resistance generated in the single-layer viscous fluid between the above-mentioned one resistance plate and the bottom surface of the viscous fluid container. There was a problem that it was low. Also, since the vertical damping device of the piston / cylinder type damper has a small damping force per unit, a large number of damping devices must be provided to cope with a large earthquake. However, there is a problem that a sufficient number of damping devices cannot be installed in the limited space of the seismic isolation layer.
The present invention has been made in view of such a problem, and an object of the present invention is to provide a damping device capable of sufficiently suppressing a response displacement of a structure due to a large earthquake in a limited seismic isolation space. .
[0007]
[Means for Solving the Problems]
Therefore, the present invention provides a damping device that constitutes a seismic isolation device that is interposed between the ground and a structure to seismically support the structure, and is fixed to the ground side and extends horizontally to extend vertically. A plurality of first horizontal plate-shaped members provided at predetermined intervals, and the first horizontal plate-shaped members fixed to the structure side and extending in the horizontal direction and provided at predetermined intervals in the vertical direction A plurality of second horizontal plate-like members alternately arranged in a state of being overlapped with each other, and chemically acting to exert a shear resistance between the first horizontal plate-like member and the second horizontal plate-like member. A fluid having a stable viscosity is interposed in a gap between the first horizontal plate-shaped member and the second horizontal plate-shaped member.
[0008]
According to such a damping device, when the ground vibrates in the horizontal direction, the plurality of second horizontal plate members vibrate along the plane direction with respect to the plurality of first horizontal plate members, A shear resistance force is generated in the plurality of layers of the fluid interposed in the gap between the horizontal plate members. The shear resistance acts in a direction to cancel the inertial force acting on the structure due to the vibration, so that the response displacement of the structure can be suppressed. Here, since the shear resistance is added by the plurality of layers of the fluid, if the number of the two horizontal plate members is increased in the vertical direction to increase the number of layers of the fluid, a limited installation is possible. The horizontal damping effect in the area can be increased.
[0009]
Further, the present invention is a damping device constituting a seismic isolation device which is interposed between the ground and a structure to seismically support the structure, the first damping device being fixed to the ground side and extending in a vertical direction. A first vertical plate-like member comprising: a vertical plate-like member; and a second vertical plate-like member fixed to the structure side, extending in the vertical direction, and arranged so as to overlap the first vertical plate-like member. A fluid having a chemically stable viscosity for exerting a shear resistance force between the member and the second vertical plate member is interposed in a gap between the first vertical plate member and the second vertical plate member. It is characterized by becoming.
[0010]
According to such a damping device, when the ground vibrates in the vertical direction, the second vertical plate-like members vibrate in the plane direction with respect to the first vertical plate-like member, and the two vertical plates vibrate. A shear resistance force is generated in the fluid interposed in the gap between the members. The shear resistance acts in a direction to cancel the inertial force acting on the structure due to the vibration, so that the response displacement of the structure can be suppressed. Here, since the shear resistance is added by the number of layers of the fluid interposed in the gap between the two vertical plate members, the number of the two vertical plate members is increased in the horizontal direction to increase the layer of the fluid. Increasing the number can increase the vertical damping effect at a limited installation height.
[0011]
Further, the present invention is a damping device that constitutes a seismic isolation device that is interposed between the ground and a structure to seismically support the structure, the damping device being fixed to the ground side and extending in a horizontal direction and extending in a vertical direction. A plurality of first horizontal plate-shaped members provided at predetermined intervals, and alternately arranged in a state of extending horizontally and provided at predetermined intervals in the vertical direction and overlapping with the first horizontal plate-shaped members. A plurality of second horizontal plate-shaped members, and a first vertical plate-shaped member extending in a vertical direction, and a movable body slidable in the horizontal direction with respect to the ground side; A second vertical plate-shaped member fixed and extending in the vertical direction and arranged so as to overlap with the first vertical plate-shaped member, wherein a second vertical plate-shaped member is provided between the first horizontal plate-shaped member and the second horizontal plate-shaped member. , And a chemically safe material for applying a shear resistance force between the first vertical plate member and the second vertical plate member. The fluid having the viscosity is interposed in the gap between the first horizontal plate member and the second horizontal plate member and in the gap between the first vertical plate member and the second vertical plate member, respectively. It is characterized by the following.
According to such a damping device, a single device can attenuate a three-dimensional response displacement.
[0012]
In addition, a first cylindrical body fixed to the ground side and opening upward, the first horizontal plate-like member or the first vertical plate-like member is disposed inside, and a lower part opening on the structure side. A second tubular body surrounding an outer peripheral surface of the first tubular body at appropriate intervals in a horizontal direction and a vertical direction, and an outer peripheral portion of the first tubular body and an inner portion of the second tubular body. The peripheral portion may be combined with an air spring connected by a sheet member so that the insides of the two tubular bodies communicate with each other and become airtight.
Thus, the air defined by the first cylindrical body, the second cylindrical body, and the sheet member becomes an air spring having three-dimensional elasticity, and the air spring is a main mechanism of three-dimensional seismic isolation. Carry.
[0013]
Further, the moving body may have a steel ball interposed on the ground side.
According to such a damping device, the rolling frictional force of the steel ball against the moving body and the ground side acts in a direction to cancel the inertial force acting on the structure due to the earthquake, and the response of the structure Displacement can be suppressed.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
=== Configuration of damping device ===
The configuration of the damping device according to the present embodiment will be described.
FIG. 1 shows a schematic sectional view of the damping device 1. A metal lower base plate 10 and an upper base plate 20 are arranged on the ground so as to face each other, and an inner cylinder 30 (first cylindrical body) and an outer cylinder each made of metal and having a cylindrical shape. 40 (the second cylindrical body) is joined in the vertical direction so as to fit. That is, the outer cylinder 40 surrounds the inner cylinder 30 coaxially in the horizontal and vertical directions at appropriate intervals as shown in FIG.
[0015]
Metal plates 31 and 32 are provided on the bottom surface and the lower inner peripheral surface of the inner cylinder 30, respectively. Metal outer disks 50 and 51 (first horizontal plate-like members) having a central portion perforated are joined to the inner peripheral surface of the metal plate 32 so as to extend at equal intervals in the vertical direction. In the present embodiment, as shown in FIG. 1, the six outer disks 51 have the same thickness, but the outer disk 50 extending to the lowermost portion is thicker.
[0016]
The inner disks 52 (second horizontal plate-shaped members) are joined to the central metal column 53 so that the six inner disks 52 (second horizontal plate members) are inserted into the six gaps formed by the outer disks 50 and 51, respectively. I have. The column 53 is supported by being joined to a metal bottom portion 54, and the bottom portion 54 is slidably supported in the horizontal direction on the surface of the metal plate 31 via a steel ball 60. Further, the upper surface of the outer peripheral portion of the bottom portion 54 is slidably held in the horizontal direction via the steel ball 60 with respect to the lower surface of the outer peripheral portion of the perforated portion of the outer disk 50. A steel ball holder (not shown) is provided on the lower surface of the bottom portion 54 and the upper surface of the outer peripheral portion so that the surface of the steel ball 60 always contacts the entire lower surface of the bottom portion 54 and the upper surface of the outer peripheral portion.
[0017]
At the upper end of the column 53, a metal bottomed cylinder having the inner cylindrical plate 55 as a side surface is joined. Inside this, three metal inner cylindrical plates 56 (first vertical plate-like members) extend coaxially and at equal intervals from the bottom to the top. The upper outer peripheral surface of the inner cylindrical plate 55 is held via steel balls 60 with respect to the outer cylindrical plate 57 surrounding the inner cylindrical plate 55 and joined to the lower surface of the upper base plate 20. Thereby, the outer cylindrical plate 57 is slidable in the vertical direction with respect to the inner cylindrical plate 55. A steel ball holder (not shown) is provided on the outer peripheral surface of the inner cylindrical plate 55 so that the surface of the steel ball 60 always contacts the outer peripheral surface of the inner cylindrical plate 55 and the inner peripheral surface of the outer cylindrical plate 57. Also, the three outer cylindrical plates 58 (second vertical plate-like members) are respectively inserted into the three gaps formed by the inner cylindrical plates 55 and 56 and joined to the lower surface of the central portion of the upper base plate 20. Has been extended. As shown in FIG. 1, the three inner cylindrical plates 56 have the same thickness, but the outermost inner cylindrical plate 55 is thicker. Also, the three outer cylindrical plates 58 have the same thickness, but the outermost outer cylindrical plate 57 is thicker.
[0018]
As described above, the outer disks 50 and 51 are fixed to the lower base plate 10 via the inner cylinder 30. On the other hand, the inner disk 52, the support 53, the bottom surface 54, and the inner cylindrical plates 55 and 56 form a moving body 70 integrally. Outer cylindrical plates 57 and 58 are fixed to the center of the upper base plate 20. The moving body 70 is slidable in the horizontal direction on the lower base plate 10 by engaging its inner disk 52 with the outer disks 50 and 51 of the lower base plate 10. The upper base plate 20 is slidable in the vertical direction by engaging its outer cylindrical plates 57, 58 with the inner cylindrical plate 56 of the moving body 70.
[0019]
In the present embodiment, the region defined by the metal plates 31 and 32 and the region defined by the inner cylindrical plate 55 have a viscous fluid 80 made of a chemically stable butane-based compound. Each is filled with. As a result, the viscous fluid 80 is interposed in the gap between the outer peripheral surface of the perforated portion of the outer disks 50 and 51 and the outer peripheral surface of the inner disk 52 overlapping each other. In addition, a viscous fluid 80 is interposed in a gap between the upper portions of the inner cylindrical plates 55 and 56 and the lower portion of the outer cylindrical plate 58 that overlap each other. In the present embodiment, the vertical distance between the outer disks 50, 51 and the inner disk 52 is approximately 20 mm, and the horizontal distance between the inner cylindrical plates 55, 56 and the outer cylindrical plate 58 is also approximately 20 mm. . These intervals are values set to obtain a predetermined shear resistance of the viscous fluid 80. When the viscous fluid 80 is made of a silicon-based compound, since the viscosity of the silicon-based compound is lower than that of the butane-based compound, the gap is made smaller than 20 mm in order to obtain a predetermined shear resistance.
[0020]
A three-dimensional air spring 90 is combined with the damping device 1 of the present embodiment. That is, a flexible rolling sheet member 91 (sheet member) is connected to the outer periphery of the opening end of the inner cylinder 30 and the inner periphery of the bottom surface of the outer cylinder 40, respectively, so that the inner cylinder 30 and the outer cylinder 40 can move in the horizontal direction. It is folded and disposed so as to hang down in the gap. As a result, air is hermetically sealed in the space defined by the inner cylinder 30, the outer cylinder 40, and the rolling sheet member 91, and an air chamber 92 is formed.
[0021]
FIG. 2 shows an embodiment in which 32 of the above damping devices 1 are combined with a three-dimensional air spring and arranged on the ground to seismically isolate the structure 100. FIG. 2 shows a plan view of the damping device 1. On the lower surface of the substantially rectangular structure 100, 32 damping devices 1 are arranged substantially uniformly and supported. However, the gap between the damping devices 1 is made wider at the central portion in the longitudinal direction of the bottom surface of the structure 100, and this is used as a maintenance space 101 of the damping device 1. Further, a total of 28 hydraulic locking prevention devices 110 are arranged at substantially equal intervals on the outer peripheral portion of the lower surface of the structure 100.
[0022]
=== Operation of the damping device ===
The operation of the attenuation device 1 according to the present embodiment will be described.
When the ground vibrates in two horizontal directions and one vertical direction in three-dimensional degrees of freedom due to an earthquake, inertia force is applied to the unisolated structure 100 in a direction opposite to the direction in which the ground is displaced. Acting directly, this inertial force causes the structure 100 to collapse.
[0023]
In the present embodiment, in the horizontal direction, the inertial force due to the earthquake acts on the moving body 70 of the damping device 1 similarly. At this time, the outer peripheral surfaces of the perforated portions of the outer disks 50 and 51 of the lower base plate 10 and the outer peripheral surface of the inner disk 52 of the moving body 70 are displaced in opposite directions, and the viscous fluid 80 sandwiched between these surfaces is displaced. Shear resistance occurs. Since the shear resistance is generated in a direction to offset the displacement, the shear resistance acts in a direction to offset the inertial force acting on the moving body 70. Therefore, the vibration of the moving body 70 linked to the horizontal vibration of the ground is attenuated. In the horizontal direction, since the upper base plate 20 is fixed to the moving body 70, if the horizontal displacement of the moving body 70 is attenuated, the horizontal displacement of the structure 100 is also attenuated.
[0024]
Since the damping device 1 of the present embodiment has twelve layers of the viscous fluid 80 in which the above-mentioned shear resistance is generated in the horizontal direction, compared with a conventional horizontal damping device having only one layer of the viscous fluid. In a limited seismic isolation space, the damping effect is about 12 times.
[0025]
In addition, the gap between the bottom portion 54 and the surface of the metal plate 31 and the gap between the upper surface of the outer peripheral portion of the bottom portion 54 and the lower surface of the outer peripheral portion of the perforated portion of the outer disk 50 are added to the shear resistance force of the viscous fluid 80. As a result, the rolling friction of the steel balls 60 abutting on the respective surfaces is generated, and this also acts on the moving body 70 in a direction to offset the inertial force due to the earthquake. Therefore, the horizontal displacement of the structure 100 is attenuated.
[0026]
The relationship between the horizontal displacement of the moving body 70 and the horizontal inertial force acting on the moving body 70 forms a hysteresis loop, and this loop is shown in FIG. The loop (calculated value) obtained by theoretical calculation modeling this embodiment and the loop (measured value) obtained experimentally by this embodiment match well, and a smooth elliptical loop is formed. I understood what to do. Generally, it has been found that such a smooth elliptical shape corresponds to a gentle seismic isolation. Therefore, it was found that the seismic isolation using the shear resistance of the viscous fluid 80 was a gentle seismic isolation. On the other hand, for example, it is known that a hysteresis loop in the case of seismic isolation using a general frictional force between solids is substantially rectangular. When following such a substantially rectangular loop, for example, at the same displacement, it is possible to rapidly transition from a state of receiving an inertial force to a state of receiving an inertial force having substantially the same magnitude as this and the opposite direction. It is known that gentle seismic isolation cannot be expected.
[0027]
When a vertical inertial force acts on the upper base plate 20 of the damping device 1, the lower portion of the outer cylindrical plate 58 of the upper base plate 20 and the upper portions of the inner cylindrical plates 55 and 56 of the moving body 70 are displaced in opposite directions. Then, a shear resistance force is generated in the viscous fluid 80 sandwiched between these surfaces. Since this shear resistance force is generated in a direction to offset the displacement, the shear resistance force acts in a direction to offset the inertial force acting on the upper base plate 20. Therefore, the vibration of the upper foundation plate 20 linked to the vertical vibration of the ground is attenuated. Therefore, the vertical displacement of the structure 100 is attenuated.
[0028]
In addition, in the gap between the outer peripheral surface of the inner cylindrical plate 55 and the inner peripheral surface of the outer cylindrical plate 57, in addition to the shear resistance of the viscous fluid 80, rolling friction of the steel balls 60 abutting on the respective surfaces is generated. However, this also acts on the upper base plate 20 in a direction to cancel the inertial force due to the earthquake. Therefore, the vertical displacement of the structure 100 is attenuated.
[0029]
Since the damping device 1 of the present embodiment has six layers of the viscous fluid 80 in which the above-mentioned shear resistance is generated in the vertical direction, the damping device 1 includes a piston and a cylinder, such as a soft plastic damper and a lead extrusion type damper. It has a particularly high damping effect in a limited seismic isolation space as compared with the conventional vertical damping device using a damper that is used.
[0030]
Since the damping device 1 of the present embodiment can simultaneously perform horizontal damping and vertical damping using the shear resistance force of the viscous fluid 80, the damping device 1 is different from the conventional damping device in which these are performed by separate devices. It has a particularly high damping effect in limited seismic isolation space.
[0031]
Further, the air sealed in the air chamber 92 provides a major seismic isolation mechanism for the structure 100 having low-rigidity elasticity in three directions of freedom in two directions horizontal to the ground and one direction perpendicular to the ground. Carry.
[0032]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to the damping device of this invention, the response displacement of the structure by a large earthquake can be suppressed sufficiently in the limited seismic isolation space.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view taken along a vertical direction of a damping device according to the present embodiment.
FIG. 2 is a plan view of the damping device according to the present embodiment.
FIG. 3 is a graph in which a horizontal inertial force corresponds to a horizontal displacement of the damping device according to the present embodiment.
[Explanation of symbols]
Reference Signs List 1 damping device 30 inner cylinder 40 outer cylinder 50, 51 outer disk 52 inner disk 55, 56 inner cylindrical plate 57, 58 outer cylindrical plate 60 steel ball 80 viscous fluid 90 three-dimensional air spring

Claims (5)

A damping device that is interposed between the ground and the structure and constitutes a seismic isolation device that supports the structure in a seismic isolation manner,
A plurality of first horizontal plate-like members fixed to the ground side and extending in the horizontal direction and provided at predetermined intervals in the vertical direction,
A plurality of second horizontal plate members fixed to the structure side, extending in the horizontal direction, provided at predetermined intervals in the vertical direction, and alternately arranged so as to overlap with the first horizontal plate members; With
A fluid having a chemically stable viscosity for applying a shear resistance between the first horizontal plate member and the second horizontal plate member is applied to the first horizontal plate member and the second horizontal plate member. Characterized by being interposed in a gap between the damping device and the damping device. A damping device that is interposed between the ground and the structure and constitutes a seismic isolation device that supports the structure in a seismic isolation manner,
A first vertical plate-shaped member fixed to the ground side and extending in the vertical direction;
A second vertical plate-like member fixed to the structure side, extending in the vertical direction, and arranged so as to overlap the first vertical plate-like member;
A fluid having a chemically stable viscosity for applying a shear resistance between the first vertical plate member and the second vertical plate member is applied to the first vertical plate member and the second vertical plate member. Characterized by being interposed in a gap between the damping device and the damping device. A damping device that is interposed between the ground and the structure and constitutes a seismic isolation device that supports the structure in a seismic isolation manner,
A plurality of first horizontal plate-like members fixed to the ground side and extending in the horizontal direction and provided at predetermined intervals in the vertical direction,
A plurality of second horizontal plate members extending in the horizontal direction and arranged at predetermined intervals in the vertical direction and alternately arranged so as to overlap with the first horizontal plate members; (1) a movable body having a vertical plate-like member and slidable in a horizontal direction with respect to the ground side;
A second vertical plate-like member fixed to the structure side, extending in the vertical direction, and arranged so as to overlap the first vertical plate-like member;
A chemically stable viscosity for applying a shear resistance between the first horizontal plate member and the second horizontal plate member and between the first vertical plate member and the second vertical plate member, respectively. And that a fluid having the following is interposed in the gap between the first horizontal plate-shaped member and the second horizontal plate-shaped member and in the gap between the first vertical plate-shaped member and the second vertical plate-shaped member. Characteristic damping device. A first cylindrical body fixed to the ground side and opening upward, and the first horizontal plate-like member or the first vertical plate-like member is disposed therein;
A second tubular body that opens downward at the structure side and surrounds the outer peripheral surface of the first tubular body at appropriate intervals in the horizontal and vertical directions,
An outer peripheral portion of the first tubular body and an inner peripheral portion of the second tubular body are connected by a sheet member so that the insides of the two tubular bodies communicate with each other and are airtight. The damping device according to claim 1, wherein the damping device is combined with an air spring. The damping device according to claim 4, wherein the moving body has a steel ball interposed on the ground side.

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