JPH04111811A - Laminate layer rubber containing visco-elastic material - Google Patents

Abstract

PURPOSE:To effectively damp vibration from the earthquake or small-vibration regions by a method in which a laminate layer rubber containing a visco-elastic material is formed by alternately bonding rubber plates and steel plates and put between the downside of a building and the base slab. CONSTITUTION:A laminate layer rubber A is made up of a laminated rubber layer 10, a top plate 20 fixed to the upside of the layer 10, and a lower plate 30 fixed to the downside of the rubber layer 10. Steel plates 11a are inserted into the rubber 11 constituting the rubber layer 10 and bonded alternately with the rubber plates 11c. A rubber asphalt (visco-elastic material) is inserted into round columnar holes of the same diameter, leading vertically to the plates 11a, the rubber plates 11c, and the upside and downside of the rubber 11b to form rubber-asphalt bodies 12. The lower plate 30 of the rubber A is fixed to the pedestal on the base plate by bolts, and the top plate 20 is attached to the downside of building. Even damping effect on the vibration of small- vibrating regions can be obtained at low cost.

Description

[Detailed Description of the Invention] [Industrial Application Field 1] The present invention consists of rubber plates and steel plates that are attached alternately, and is interposed between the lower surface of a building and a foundation plate to prevent vibrations caused by earthquakes, etc. This invention relates to a laminated rubber containing absorbent viscoelastic material.

[Prior Art] In recent years, there has been an increase in the number of cases in which seismic isolation devices that absorb vibrations generated in buildings due to earthquakes, wind, etc. are actually employed.

Conventional seismic isolation devices can be roughly divided into four types.

■Sailor's Laminated Rubber A lead rod damper and laminated rubber are integrated, and even if the lead inside is plastically deformed, it quickly recovers and maintains its original damping performance. Laminated rubber is made by laminating thin rubber and steel plates alternately, and is soft in the horizontal direction.
It has a hard property in the vertical direction.

Its advantages are that it has a large damping performance, that it is easy to recrystallize to restore performance after plastic deformation of lead, so there is less need for replacement in the event of an earthquake, and that the supporting device and damping mechanism of the seismic isolation device are integrated. Therefore, the seismic isolation device is easy to handle, and the vibration system is nonlinear and undefined, so resonance phenomena are less likely to occur.

■Laminated rubber + steel damper Steel tamper absorbs earthquake energy by plasticizing the steel material, and is particularly effective during large earthquakes.

Its advantages are that it has a large damping performance, and that the supporting device and damping mechanism of the seismic isolation device are independent, making it easy to plan the structure of the seismic isolation device for upper buildings that are prone to torsional deformation [7. The vibration system is nonlinear and undefined, so resonance phenomena are less likely to occur.

■Laminated rubber + oil damper The oil damper exhibits stable damping force characteristics from small amplitudes to large amplitudes. The combination of this damper and laminated rubber suppresses the displacement of buildings during earthquakes.

Its advantages are that it can be expected to have a damping effect in the micro-amplitude region, making it advantageous for small and medium-sized earthquakes, and that the damping mechanism does not rely on hysteresis energy due to plastic deformation, so there is less need to replace tampers during earthquakes, and response is linear, making it easy to predict the response during a large earthquake, and making it easy to set the damping performance.

■High damping laminated rubber This is a rubber laminated rubber with higher damping properties than the above laminated rubber. This makes it possible to absorb horizontal vibrations during earthquakes.

[Problems to be Solved by the Invention] However, the above-mentioned conventional technology has the following problems.

Lead-containing laminated rubber and laminated rubber+steel dampers utilize the history characteristics of the material for damping characteristics, so damping effects cannot be expected in small amplitude regions.

Since the laminated rubber + oil damper uses an oil damper, construction is complicated, and the stroke of the tamper becomes the limit displacement of the building, and increasing this increases the cost.

Highly damped laminated rubber is also more expensive than ordinary laminated rubber.

The present invention has been made in view of such problems,
The objective is to provide a laminated rubber containing a viscoelastic material that can be expected to have a damping force in a small amplitude region and is less expensive than conventional techniques.

[Means for Solving the Problems] The gist of the present invention is to provide a rubber plate and a steel plate alternately attached to each other, and to provide a sticky material that absorbs vibrations caused by earthquakes, etc. by interposing it between the lower surface of a building and a foundation plate. The present invention relates to a laminated rubber containing a viscoelastic material, which is characterized in that the rubber contains a viscoelastic material inside.

[Operation] Unlike a plastic body, a viscoelastic body exhibits a damping effect through elastic deformation even in a small amplitude region.

Since the rubber used for the laminated rubber is less expensive than high-damping rubber, it is less expensive than conventional technology.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in this example are not intended to limit the scope of this invention to only those, unless specifically stated. It's just an illustrative example.

The laminated rubber containing viscoelastic material according to this example will be explained using FIG. 1.

As shown in FIG. 1, the laminated rubber containing comb asphalt (laminated rubber containing viscoelastic material) A is fixed to the laminated rubber 10 and the upper surface of the laminated rubber 10, and is fixed to the upper plate 20 and the lower surface. It consists of a lower plate 30 consisting of:

The laminated rubber 10 is composed of a laminated rubber main body 11 and comb asphalt 12 (viscoelastic material). The laminated rubber main body 11 includes a plurality of iron plates 11a and each iron plate 1.
1a and a rubber portion 11b that includes a rubber portion 1a. Each of the iron plates 11a is an annular plate-shaped body having a hole of the same diameter in the center in a plan view. The rubber part 11b includes a plurality of plate-like parts 11c that are spaced apart by the thickness of the iron plate 11a, and a cylindrical part that supports each of the plate-like parts 11c and forms a side surface of the rubber part 1↓b. It is a cylindrical body consisting of a lid. A hole having the same diameter as the hole is provided at the center on the upper and lower surfaces of each of the plate-shaped portions 11c and the rubber portion 11b. Each of the iron plates 11a is stored in a space partitioned by each of the plate-like parts 11c,
The plate-shaped portion 11C and the iron plate 11a are attached to each other. The rubber asphalt 12 has the plate-like portion 11C.
It is a cylindrical body existing inside a hole that communicates in the vertical direction and is formed by adhering the iron plate 11a and the iron plate 11a to each other.

The upper plate 2o and the lower plate 30 are both steel plate-shaped bodies that are circular in plan view and have a diameter larger than the diameter of the laminated rubber 10.

Installation on the rubber asphalt-containing laminated rubber can be done in the same way as in the past, by fixing the lower plate 30 to a pedestal provided on the base plate with bolts or the like, and attaching the upper plate 20 to the lower surface of the building.

Next, the effects of the rubber asphalt-containing laminated rubber A constructed as shown below will be explained.

Lead-containing laminated rubber absorbs vibration energy through plastic deformation of lead and exhibits damping performance. Therefore, if the seismic input is small and lead is in an elastic state, no damping effect can be expected. On the other hand, by using the rubber asphalt 12, which is a viscoelastic material, it is possible to exhibit a damping effect in a small amplitude region.

Furthermore, since the comb used in the laminated rubber 10 is less expensive than high-damping rubber, according to this embodiment, the price of the seismic isolation device is lower than that of a seismic isolation device using high-damping rubber. can be made cheaper.

Nao, in this embodiment, the number of rubber asphalt 12 is one, but this is not intended to limit the scope of the present invention, and the present invention may have other configurations, such as six as shown in FIG. , the number can be set to a suitable number for implementing the present invention.

Further, although the shape of the rubber asphalt 12 is a cylinder, this is not intended to limit the scope of the present invention, and the present invention may use other shapes such as truncated cones or other shapes suitable for carrying out the present invention. It can be done.

Further, although rubber asphalt 12 was used as the viscoelastic material, this is not intended to limit the scope of the present invention, and in the present invention, other materials such as soft polyvinyl chloride, epichlorohydrin rubber, nitrile rubber, urethane rubber, etc. Any suitable material can be used to carry out the present invention.

Finally, there are experimental results of a vibration damping device using the same viscoelastic body, although the configuration is different from that of the seismic isolation device in this example, so they will be described here.

■Experiment outline (a) Force device reaction force Consisting of a Heath mat rigidly connected to the floor, a force beam, four columns supporting the force beam, and a reaction beam that receives the reaction force of the vibration damping device. There is.

The loading beam is supported by rollers at four locations where it intersects with the pillars.
Excited by the actuator via the reaction wall. The damping device is fixed to the force beam and the reaction beam using high-strength bolts, and if an external force is applied to the force beam, the vibration damping device will undergo relative deformation.

(b) Vibration damping device The vibration damping device consists of a sheet-like viscoelastic body molded to a thickness of 5 mm and six iron plates sandwiching the viscoelastic body. move in opposite directions. Therefore, the viscoelastic body is a mechanism that generates a damping force against the relative deformation that occurs between the steel plates. In addition,
The temperature during the experiment was 20'C1, and the effective cross-sectional area of the viscoelastic body was 10
It is 2m2.

(C) Loading planning Loading was performed by displacement control using a differential transformer displacement type attached to the loading beam. Figure 3 shows the applied case, but the excitation mainly involves small deformations (L 3.5 mm).
There are two main categories: cases where the target amplitude is 15 mm, and cases where the target amplitude is larger than that (with an upper limit of about 15 mm). Also, -15m
After being deformed by about 15 mm, the sample is again deformed by about 15 mm.

■6 Experimental results (a) History loop Figure 4 shows a constant amplitude of 0.333Hz (1.35mm).
The history loop for the case is shown. When the deformation exceeds 5 mm, it approaches a conical shape. In addition, if the deformation is about 5 mm, there is no decrease in rigidity due to repeated constant displacement, or if the deformation is about 5 mm.
When it becomes more than m, the rigidity decreases by about 10 to 15% at most.

(b) Damping car speed relationship Figure 5 shows the relationship between the damping force and the relative speed between the iron plates. From this, if the speed is kept constant, the damping force tends to be larger as the frequency is lower, and if the frequency is kept constant, the damping force tends to be larger as the deformation is larger. However, when the speed exceeds a certain value (which varies depending on the frequency), an upper limit value of the damping force exists regardless of the frequency.

(c) Equivalent damping coefficient-speed relationship FIG. 6 shows the relationship between the equivalent damping coefficient and relative velocity.

From this, if the speed is kept constant, the damping coefficient tends to be larger as the frequency is lower, and if the frequency is kept constant, the damping coefficient tends to be smaller as the deformation becomes larger. However, in a range where the deformation is small, the coefficient becomes a nearly constant value.

(d) Rigidity-Speed Relationship The relationship between stiffness and relative speed is shown in Figure 7. From this, if the speed is constant, the higher the vibration frequency, the higher the rigidity; if the frequency is constant, the higher the deformation, the higher the rigidity; and if the frequency is constant, the higher the deformation, the lower the stiffness tends to be. However, in a small deformation range, the stiffness remains approximately constant.

Although the above results were obtained through the above experiment, a similar damping effect can be expected from the rubber asphalt-containing laminated rubber A using a viscoelastic body.

[Effects of the Invention] Since the present invention is configured as described above, it has the following effects.

Viscoelastic bodies, unlike plastic bodies, exhibit a damping effect through elastic deformation even in small amplitude regions, and the rubber used for laminated rubber is cheaper than high-damping rubber, so the present invention You can expect damping force in the area, and
The price can be lowered compared to conventional technology.

[Brief explanation of the drawing]

FIG. 1 is a -N@ plane perspective view showing a laminated rubber containing rubber asphalt according to one embodiment of the present invention, FIG. 2 is a perspective view of a laminated comb containing rubber asphalt according to another embodiment, and FIG. Figure 4 shows the force case table, Figure 4 shows the history loop,
FIG. 5 is a diagram showing the relationship between damping force and speed, FIG. 6 is a diagram showing the relationship between equivalent damping coefficient and speed, and FIG. 7 is a diagram showing the relationship between stiffness and speed. A... Laminated rubber with rubber asphalt, 10...
...Laminated comb, 11...Laminated rubber body, 11
a... Iron plate, llb... Plate-shaped part, 12...
...Rubber asphalt.

Claims (1)

[Claims] It is a laminated rubber with a viscoelastic material that is made by alternately pasting rubber plates and steel plates and is interposed between the bottom surface of a building and the foundation plate to absorb vibrations caused by earthquakes, etc., and has a viscoelastic material inside. A laminated rubber containing a viscoelastic material.