JP2009228851A - Lamination layer rubber for seismic isolation - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lamination layer rubber for seismic isolation preventing destruction due to great deformation when a giant earthquake bigger than expected happens, and also absorbing and relieving a shock when deformation is prevented. <P>SOLUTION: In the lamination layer rubber for seismic isolation, rubber layers 10 and intermediate steel plates 11 are laminated alternately, vulcanized and bonded, and a lamination layer rubber body 3 having a hollow part 2 at the center is sandwiched by a pair of upper and lower flange plates 4, 5. A tension control member 6 having non-extensibility penetrattes through the hollow part 2. One end part of the tension control member 6 is connected to the upper flange plate 4, and the other end part is connected to the lower flange plate 5 via elastic washers 14, 17 respectively. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a seismic isolation laminated rubber, and more particularly to a seismic isolation laminated rubber suitable for lightweight structures such as houses.

In the case of a seismic isolation laminated rubber for light-weight structures such as houses, in order to increase the period, a method is adopted in which the pressure receiving area is reduced and the total rubber thickness is increased in order to reduce the horizontal rigidity. At this time, in order to prevent buckling, a hollow structure is adopted in which the outer diameter and inner diameter of the laminated rubber are increased so that the apparent secondary shape factor (S ₂ ) is increased (see, for example, Patent Document 1). .)

However, the above-mentioned seismic isolation laminated rubber, which has a hollow structure with a larger outer diameter and inner diameter of the laminated rubber, improves the horizontal deformation capability, but if the large deformation occurs during an excessive earthquake beyond the expected level, the laminated rubber will break down. End up.
As a fail-safe mechanism that prevents the laminated rubber from being deformed excessively when an earthquake force exceeding this assumption is applied, a displacement control stopper is installed in parallel to the outside of the laminated rubber, or laminated rubber The chain is passed through a hollow part of laminated rubber that is sandwiched between a pair of upper and lower flange plates, and one end of the chain is connected to the upper flange plate. The other end is inserted into and engaged with the central hole of the lower flange plate, and this chain functions as a stopper that prevents deformation beyond the limit of the laminated rubber (for example, Patent Document 2). See.)

However, in the case where the stopper for displacement control is installed in parallel to the outside of the laminated rubber, there is a demerit that a large installation space is required and the number of construction steps is increased.
On the other hand, if a stopper made of a tensile force suppressing chain or the like is incorporated in the hollow portion of the laminated rubber, there is an advantage that the man-hour at the time of construction can be reduced with a small space.

JP-A-9-72378 JP 63-103719 A

  However, if a stopper made of a chain for suppressing tensile force is incorporated in the hollow part of the laminated rubber, it has the above-mentioned merit, but when the stopper is used to prevent large deformation of the laminated rubber, a large impact is applied, and both ends of the stopper There were problems such as deformation and damage to the upper and lower flange plates and stoppers.

  The present invention has been made to solve such problems, and the object of the present invention is to further improve the above-described one that incorporates a stopper for suppressing tensile force in the hollow portion of the laminated rubber. Accordingly, an object of the present invention is to provide a laminated rubber for seismic isolation that can prevent large deformation and breakage during an excessive earthquake more than expected, and can absorb and mitigate shocks at the time of deformation prevention.

The present invention relates to a seismic isolation laminated rubber comprising a laminated rubber body in which a rubber layer and an intermediate steel plate are alternately laminated and vulcanized and bonded, and a hollow portion is provided in the center and sandwiched between a pair of upper and lower flange plates. In the hollow portion, a non-extensible tensile force suppressing member having a predetermined length that is tensioned at the time of a large deformation during an excessive earthquake more than expected and relaxed in a normal state is passed, and one end portion of the tensile force suppressing member is inserted into the hollow portion. The other end portion of the upper flange plate is connected to the lower flange plate via an elastic washer.
In this case, a wire or a link chain can be used for the tensile force suppressing member.
According to the seismic isolation laminated rubber having such a configuration, the tensile force restraining member is displaced and relaxed in the compressing direction in a normal state, thereby obstructing the movement of the laminated rubber body or applying an extra load. There are no seismic isolation functions.
In the event of an excessive earthquake that is greater than expected, the tensile force restraining member is displaced and tensioned in the extending direction along with the displacement of the laminated rubber body to restrain the tensile force acting on the laminated rubber body, thereby preventing the laminated rubber body from being destroyed. When the tensile force is restrained by the tensile force restraining member, elastic washers are interposed in the joint portion between the upper flange plate and one end portion of the tensile force restraining member and the joint portion between the lower flange plate and the other end portion of the tensile force restraining member. Therefore, the tensile force restraining member starts to work softly, can absorb and relax the impact, and the upper and lower flange plates and the tensile force restraining member that hold both ends of the tensile force restraining member are prevented from being deformed or damaged. it can.

  According to the laminated rubber for seismic isolation of the present invention, it is possible to prevent a large deformation and breakage during an excessive earthquake more than expected, and to absorb and relieve an impact at the time of deformation prevention. It is advantageous to protect against deformation and breakage of the upper and lower flange plates and the tensile force suppressing member.

  Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a seismic isolation laminated rubber according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a state of the seismic isolation laminated rubber of FIG.

  As shown in FIG. 1, a seismic isolation laminated rubber 1 according to the present invention includes a laminated rubber body 3 having a hollow portion 2 formed in the center, and a pair of upper and lower metal flange plates 4 sandwiching the laminated rubber body 3. 5 and a non-extensible tensile force suppressing member 6 installed in the hollow portion 2 of the laminated rubber body 3.

  The laminated rubber body 3 is formed by alternately laminating a donut-shaped rubber layer 10 and a donut-shaped intermediate steel plate 11 made of natural rubber or high damping rubber between a pair of upper and lower donut-shaped connecting plates 8 and 9. While forming the hollow part 2, it shape | molds by carrying out the vulcanization | cure adhesion | attachment in the state which coat | covered the weather resistance, ozone resistance, and the moisture-proof protective rubber layer 12 in those outer peripheral parts.

  The tensile force suppression member 6 is for passing through the hollow portion 2 and connecting the upper and lower flange plates 4 and 5 so that the laminated rubber main body 3 has a function of making it difficult to receive a tensile load during an excessive earthquake. It consists of a wire, a link chain, or the like made of steel having a predetermined length that is tensioned at the time of a large deformation in the event of an excessive earthquake and relaxes in a normal state, that is, a design maximum displacement length.

  One end portion 6a of the tensile force suppressing member 6 is passed from below into the sinking center hole 13 of the upper flange plate 4, and one end portion 6a protruding into the center hole 13 is made of elastic material such as fiber reinforced rubber or urethane elastomer. The screw 15 is tightened through the washer 14 to be coupled and fixed. The other end 6b of the tensile force suppressing member 6 is also passed from above into the sinking center hole 16 of the lower flange 5, and the other end 6b protruding from the center hole 16 is made of elastic material such as fiber reinforced rubber or urethane elastomer. The screw 18 is tightened through the washer 17 to fix it.

  As shown in FIG. 1, the seismic isolation laminated rubber 1 configured as described above is displaced in a relaxed state by being displaced in a direction in which the tensile force suppressing member 6 is compressed in the hollow portion 2 of the laminated rubber main body 3. In this state, the deformation operation within the design displacement of the laminated rubber body 3 is not hindered.

  When an excessive earthquake more than expected occurs and the laminated rubber main body 3 is deformed more than the design displacement, the tensile force suppressing member 6 is displaced and tensioned in the extending direction as shown in FIG. In order to suppress the tensile force, the laminated rubber main body 3 is prevented from being broken, and the load supporting and restoring force characteristics are maintained. At this time, since the elastic washers 14 and 17 are interposed at the joints between the both end portions 6a and 6b of the tensile force suppression member 6 and the upper and lower flange plates 4 and 5, the tensile force suppression member 6 is tensioned and functions as a stopper. Begins to work softly and absorbs and reduces the impact by the elastic washers 14 and 17, so that the upper and lower flange plates 4 and 5 holding the both ends of the tensile force suppressing member 6 and the tensile force suppressing member 6 are deformed or damaged. Can be prevented.

It is sectional drawing of the laminated rubber for seismic isolation which shows one Example of this invention. It is sectional drawing which shows the state at the time of the large deformation | transformation of the seismic isolation laminated rubber of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Seismic isolation laminated rubber 2 Hollow part 3 Laminated rubber main body 4,5 A pair of upper and lower flange plates 6 Tensile force suppressing member 10 Rubber layer 11 Intermediate steel plate 14, 17 Elastic washer

Claims (2)

  In the seismic isolation laminated rubber formed by alternately laminating rubber layers and intermediate steel plates, vulcanizing and bonding them, and sandwiching a laminated rubber body having a hollow portion at the center between a pair of upper and lower flange plates, the hollow Pass a predetermined length and non-extensible tensile force restraining member that is tensioned at the time of a large deformation in the event of an excessive earthquake or more than expected and relaxes normally, and one end of the tensile force restraining member passes through the upper flange plate. The seismic isolation laminated rubber is characterized in that the other end is coupled to the lower flange plate via an elastic washer.   The seismic isolation laminated rubber according to claim 1, wherein the tensile force suppressing member comprises a wire or a link chain.

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