JPH04189969A - Base isolation - Google Patents

Abstract

PURPOSE:To reduce height by installing high damping multistage lamination rubbers installed at plural positions on a floor slab, upper and lower frames and a supporting member for fixing a floor panel over the lower frame. CONSTITUTION:A high damping type multistage lamination rubber 2 is erected on a floor slab 1, and an upper frame 3 is installed, and lower frames 5 are suspended at plural places through wires 4 as connecting members, and a pendulum structure which is relatively shiftable is formed. Then, the vibration of an earthquake, etc., is reduced by the pendulum structure due to the rubber 2 and the member 4, during the time when the vibration is transmitted to a floor panel 7 fixed on the frame 5. Accordingly, the pendulum structures due to the rubber 2 and the member 4 are connected in series in equivalent form, and the height of the slab 1 and the floor panel 7 can be suppressed by adjusting the piling height of the rubber 2, maintaining the earthquakeproof function.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a seismic isolation floor structure that reduces vibrations applied to floors on which precision equipment is installed in nuclear reactor buildings, computer rooms, semiconductor factories, etc.

<Prior Art> Various seismic isolation floor devices and seismic isolation floor structures have been proposed in the past.

For example, multiple rubber-like elastic bodies are stacked one above the other.

A multi-stage seismic isolation floor device (Japanese Unexamined Patent Publication No. 62-41874) has been proposed in which the upper and lower end surfaces of the rubber elastic bodies of each stage are connected by stabilizing plates. With this device, the high-damping multi-layered rubber layers can be leveled without buckling. It is possible to sufficiently lower the natural frequency in the direction.

<Problems to be Solved by the Invention> However, in order to sufficiently reduce the natural frequency using the high damping multi-layered rubber, it is necessary to stack the rubber layers high in multiple stages via a stabilizing plate. For this reason, there was a problem in that the supported floor panel was positioned higher than the floor slab on which the high-damping multi-layer laminated rubber was installed.

Therefore, as a structure to reduce this height, a high-damping multi-layer laminated rubber is set up on the splash slab, a support member is fixed on top of it, and a frame located below the support member is fixed to this support member. In addition, a seismic isolation floor system (Utility Model Publication No. 2-1884) was developed to fix the floor panel to the frame.
No. 8) has been proposed.

According to this system, the position of the floor panel can be lowered to some extent, but in order to maintain the seismic isolation function, the high-damping multi-layered rubber is stacked at the same height as before, and the floor panel and floor panel are stacked at the same height. In order to keep the height of the building low, there was a desire for a seismic isolation structure in which the high-damping multi-layered rubber was constructed low, while maintaining the conventional seismic isolation function.

The present invention has been made in view of the above problems.

The purpose of this is to maintain the same seismic isolation function as before, even when the stacking height of high-damping multi-layered rubber is configured to be low.
To provide a seismic isolation floor structure capable of keeping the height between a floor slab and a floor panel low.

<Means for Solving the Problems> The present invention has been made in view of the above object, and the gist thereof is to provide highly attenuated multi-layered laminated rubber installed at multiple positions of a floor slab, and a structure in which the high-damped multi-layered laminated rubber is installed at multiple positions on a floor slab. The lower frame is suspended below the upper frame via a connecting member, and the support member for fixing the floor panel above the lower frame is constructed of the high damping multi-layered rubber. and the connecting member are connected equivalently in series.

Further, another gist of the present invention is that in the seismic isolation floor structure,
An elastic member that absorbs vibrations through elastic deformation and a friction material that has a damping effect due to frictional force are interposed in series between the lower frame and the floor slab, and the elastic member is connected to the lower frame. It has a seismic isolation floor structure with floor slabs that apply compressive surface pressure.

<Operation> The lower frame is suspended from the upper frame via a connecting member, and therefore the lower frame and the upper frame form a pendulum structure that is relatively movable.

Therefore, when seismic motion or the like is applied to the floor slab, this vibration is transmitted to the upper frame after being reduced by the high-damping multi-layered rubber. Furthermore, the signal is transmitted from the upper frame to the lower frame via a connecting member. At this time, since the lower frame side serves as the fulcrum side of the pendulum, vibrations in the upper frame are reduced on the lower frame side.

In this way, the high-damping multi-layer laminated rubber and the pendulum structure formed by the connecting member are equivalently connected in series, and the action of both reduces vibrations applied to the floor panel fixed to the lower frame. .

<Example> A seismic isolation floor structure according to the present invention will be explained based on the attached drawings.

As shown in FIGS. 1 and 2, high-damping multi-layer laminated rubber 2 is erected at four locations on a floor slab 1, and an upper frame 3 is constructed thereon in a frame shape. Further, in a pair of opposing upper frames 3, lower frames 5 assembled in a lattice shape are suspended at a plurality of locations via wires 4 as connecting members. teeth,
It has a pendulum structure that can be relatively displaced via a wire 4. Further, a pedestal 6 serving as a support member is erected upward on the lower frame 5, and a floor panel 7 is fixed to the upper end of the pedestal 6.

On the other hand, a soft rounding 8 having appropriate spring constants in the vertical and horizontal directions is interposed between the floor slab 1 and the lower frame 5, as shown in FIG. The structure of this soft rounding 8 is such that on the lower surface of the lower frame 5,
A high-damping laminated rubber 8a as an elastic member that absorbs vibrations through elastic deformation is attached, a bottom friction plate 8b as a friction material is fixed to the lower surface of the rubber, and a hem plate 8c is fixed to the floor slab l. The bottom friction plate 8b is positioned approximately at the center of the bottom friction plate 8c. At this time, in order to bring the soft rounding 8 into a triggered state, the load applied by the lower frame 5 is adjusted so that a slight compressive surface pressure in the vertical direction is applied to the high damping laminated rubber 8a. .

In the seismic isolation floor structure having such a configuration, when vibrations such as seismic vibrations are applied to the floor slab 1, the floor slab 1 mainly oscillates in the longitudinal and lateral directions within the plane at a natural period. This vibration is reduced through the high-damping multi-layered rubber 2 and transmitted to the upper frame 3 fixed to the upper part thereof. Furthermore, this swinging is transmitted from the upper frame 3 to the lower frame 5 via the wire 4.
transmitted to.

Here, as mentioned above, the upper frame 3 and the lower frame 5 form a pendulum structure via the wire 4,
When the swing motion is transmitted, the lower frame 5 side acts as the fulcrum side of the pendulum, so the swing motion of the upper frame 3 is reduced on the lower frame 5 side. Therefore, vibrations such as seismic motion applied to the floor slab l will be absorbed by the lower frame 5.
This is reduced by the pendulum structure formed by the high-damping multi-layered rubber 2 and the wire 4 while reaching the floor panel 7 fixed to the floor panel 7.

In this case, the function of the soft rounding plate 8 is
In a low-load state in which the bottom friction plate 8b does not slide relative to c, the vibration of the lower frame 5 transmitted by the seismic motion or the like is absorbed by shear deformation of the high-damping laminated rubber 8a. In addition, under heavy load conditions where shaking such as earthquake motion is intense, sliding occurs between the low-friction plate 8b and the sliding plate 8c, and this horizontal kinetic energy is converted into thermal energy due to the friction between the two. This reduces the vibration of the

In this embodiment, the wire 4 is used as an example of the connecting member, but instead of the wire, a rod member is used, and both ends of the rod member are connected to the upper and lower frames through a universal joint, etc.
The answer is not limited as long as the upper and lower frames can be connected to form a pendulum structure that can be mutually displaced.

In addition, although high-damping laminated rubber is used in Soft Rounding 8, coil springs, disc springs, leaf springs, etc. may also be used, and low-friction materials such as rollers and ball bearings may be used instead of the bottom low-friction plate. It is possible to use members.

<Effects> According to the seismic isolation floor structure according to the present invention, since the upper frame is installed between the high-damping multi-layered rubber laminated rubber installed on the floor slab,
Vibrations such as seismic motion transmitted to the floor slab can be reduced on the upper frame side by the high damping multi-layered rubber.

Further, since the lower frame is suspended from the upper frame via the connecting member, the upper frame and the lower frame form a pendulum structure that can be relatively displaced, and the lower frame side acts as the fulcrum side of the pendulum. , vibrations in the upper frame can be reduced on the lower frame side.

Therefore, since the structure is such that the high-damping multi-layered rubber and the pendulum structure formed by the connecting member folded downward from the upper end of the high-damping multi-layered rubber are connected isometrically in series, it is different from the conventional structure. While maintaining the same seismic isolation function, the stacking height of the high-damping multi-layered rubber can be kept low, making it possible to keep the height of the floor slab and floor panel lower than before.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing the seismic isolation floor structure according to the present invention with the floor panel removed, Fig. 2 is a side view of the seismic isolation floor structure, and Fig. 3 is an enlarged side view showing the soft rounding. It is. 1. Floor slab, 2. High damping multi-layer laminated rubber, 3. Upper frame, 4. Wire (connecting member), 5. Lower frame, 6. Pedestal (supporting member), 7. Floor panel. .

Claims (1)

[Claims] 1) High-damping multi-layered laminated rubber installed at multiple positions on a floor slab, an upper frame installed between the high-damping multi-layered rubber, and suspended below the upper frame via a connecting member. A seismic isolation system comprising a lower frame for fixing a floor panel above the lower frame, and a support member for fixing a floor panel above the lower frame, and the seismic isolation is characterized in that the high damping multi-layered rubber and the connecting member are equivalently connected in series. floor structure. 2) An elastic member that absorbs vibration through elastic deformation and a friction material that has a damping effect due to frictional force are interposed in series between the lower frame and the floor slab, and the elastic member has the 2. The seismic isolation floor structure according to claim 1, wherein the seismic isolation floor structure is arranged by applying compressive surface pressure by a lower frame and a floor slab.