JPH0520841Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a seismic isolation device for structures such as nuclear reactors, bridge piers, and ultra-precision processing factories.

[Prior Art] Conventionally, an elastic body that supports the vertical load of the structure and elastically deforms in response to the horizontal load, and an elastic body that supports the vertical load of the structure and a predetermined elastic body that supports the horizontal load of the structure are used between various structures and their foundations. Seismic isolation means for a structure that includes a steel rod damper that deforms plastically through elastic deformation is disclosed in, for example, Japanese Patent Laid-Open No. 60-223576 and Japanese Patent Laid-Open No. 60-250170.

[Problems to be solved by the invention] However, in the case of the seismic isolation means disclosed in the above-mentioned published patent application, all of the steel bar dampers operate from the beginning, and the rigidity remains unchanged until the steel bar damper enters the plastic region. Since the is constant, environmental vibrations, wind power, small to medium earthquakes, etc. are input to the structure through the same stiffness as during a large earthquake, thus obtaining the optimal restoring force characteristics according to the input level. There was a problem that I couldn't do anything.

The present invention aims to provide a seismic isolation device for a structure that has an optimal input reduction effect and energy absorption capacity for various levels of input seismic motion.

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned conventional problems, and its gist is that between the foundation and the structure, there is a An elastic body that supports loads and elastically deforms against horizontal overload, and a steel rod whose lower end is restrained and whose upper end is supported so that it can only slide vertically, and which operates from the beginning against the horizontal load of the structure. A seismic isolation device for a structure that includes a damper and a steel rod damper whose lower end is rotatably supported on a spherical surface, whose upper end is supported so as to be slidable up and down, and which operates after being horizontally displaced to a certain extent in response to the horizontal load of the structure. It is in.

[Function] As mentioned above, between the foundation and the structure, there is an elastic body that supports the vertical load of the structure and deforms elastically against the horizontal load, and a steel that acts from the beginning against the horizontal load of the structure. We decided to install both a bar damper (restoring force characteristics shown in Figure 1 A) and a steel rod damper (restoring force characteristics shown in Figure 1 B) that operates after a certain amount of horizontal displacement in response to the horizontal load of the structure. Therefore, it is possible to obtain optimal restoring force characteristics depending on the input level.

For example, as shown in FIG. As shown in Figure D, damper area A' for wind power and small to medium earthquakes, damper area B' for large earthquakes, and damper area C' for suppressing large displacements are set at the input level. Restoration properties that function accordingly can be obtained.

Note that in Figure 1 A, B, C, and D, Q is the horizontal load and δ is the horizontal displacement.

[Example] An example of the device of the present invention will be described below with reference to FIGS. 3 and 4.

As shown in FIG. 3, an elastic body 3 is provided between the foundation 1 and the structure 2 to support the vertical load of the structure 2 and to elastically deform in response to the horizontal load. The elastic body 3 is made of laminated rubber, for example, in which elastic bodies such as rubber and metal plates are alternately stacked.

On the other hand, a lower support jig 4 is fixed to the foundation 1, and an upper support jig 5 is fixed to the structure 2 opposite to this lower support jig 4.

One side of the lower support jig 4 and the upper support jig 5
A steel rod damper 6 that operates from the beginning against the horizontal load of the structure 2 is provided between the structure 2 and one side thereof.

Further, between the other side of the lower support jig 4 and the other side of the upper support jig 5, there is provided a steel rod damper 7 that operates after being horizontally displaced to some extent in response to the horizontal load of the structure 2. It is being

The means for installing the steel rod damper 6 that operates from the beginning is to penetrate the lower end of the steel rod damper 6 in spherical contact with the through hole 4b of the top wall 4a of the lower support jig 4, and then insert the lower end of the steel rod damper 6 into the lower support jig 4 in spherical contact with the through hole 4b. It is fixed to the bottom wall 4c of the fixture 4, and the upper end of the steel rod damper 6 is installed by penetrating the bottom wall 5a of the upper support jig 5 and the through hole 5c of the top wall 5b in spherical contact.

In other words, the steel rod damper 6 operates from the beginning.
is restrained between the top wall 4a and the bottom wall 4c of the lower support jig 4 over a certain length range at its lower end, and the upper support jig 4 over a certain length range at its upper end. Through holes 5c in the bottom wall 5a and top wall 5b of the jig 5
It is supported in between so that it can only slide vertically.

Further, as a means for installing the steel bar damper 7 which operates after being horizontally displaced to a certain extent, the lower end of the steel bar damper 7 is loosely inserted into the large diameter hole (blind hole) 4d of the top wall 4a of the lower support jig 4. , its lower end is connected to a spherical joint 4e provided on the bottom wall 4c of the lower support jig 4.
The upper end of the steel rod damper 7 is loosely inserted into the large diameter hole (blind hole) 5d of the bottom wall 5a of the upper support jig 5, and its upper end is brought into spherical contact with the through hole 5e of the top wall 5b. Penetrate and install.

That is, the steel bar damper 7, which operates after being horizontally displaced to a certain extent, has only its lower end supported in a spherical rotation on the bottom wall 4c of the lower support jig 4, and
Its upper end is the through hole 5 of the top wall 5b of the upper support jig 5.
It is supported so that it can slide up and down.

When we conducted an experiment on the vertical sliding of the upper end of the steel rod damper 7, which operates after horizontally changing to a certain extent in response to the horizontal load, we found that the vertical sliding history curve as shown in Fig. 2 was obtained. Experimental results were obtained.
From this curve diagram, the upper end of the steel rod damper 7, which operates after a certain amount of horizontal displacement in response to the horizontal load, slides up and down while rotating in the direction along the horizontal relative displacement, and the upper end of the steel rod damper 7 operates after a certain amount of horizontal displacement in response to the horizontal load. It can be seen that restoring force characteristics were obtained.

Although the lower support jig 4 and the upper support jig 5 are commonly used by the two steel bar dampers 6 and 7, they may be separate for each steel bar damper 6 and 7.

In addition, as a means for spherically rotating the lower end of the steel bar damper 7, which operates after being horizontally displaced to a certain extent, it is possible to use not only the spherical joint 4e but also other means such as a universal joint 4f as shown in FIG. Conventional means may be used.

[Effects of the invention] As described above, according to the seismic isolation device of the invention,
From environmental vibrations to large earthquakes, it is possible to obtain optimal input reduction effects and energy absorption capabilities for structures depending on the input level.

However, the upper end of the steel rod damper, which operates after a certain amount of horizontal displacement in response to the horizontal load of the structure, slides up and down while rotating in the direction along the horizontal relative displacement, so it has excellent restoring force characteristics. A seismic isolation device for the structure is obtained.

[Brief explanation of the drawing]

Figure 1 A, B, C, and D are restoring force characteristic diagrams of the steel bar damper in the device of the present invention, and Figure 2 is the vertical sliding of the upper end of the steel bar damper that operates after a certain amount of horizontal displacement in response to a horizontal load. A history curve diagram, FIG. 3 is a schematic diagram showing an embodiment of the device of the present invention, and FIG. 4 shows another embodiment of a means for spherically rotating the lower end of a steel rod damper that operates after being horizontally displaced to a certain extent. It is a schematic diagram. In the figure, 1 is the foundation, 2 is the structure, 3 is the elastic body, 4
is a lower support jig, 4e is a spherical joint, 4f is a universal joint, 5 is an upper support jig, and 6 and 7 are steel rod dampers.

Claims (1)

[Scope of utility model registration request] Between the foundation and the structure, there is an elastic body that supports the vertical load of the structure and deforms elastically in response to horizontal loads; A steel rod damper that operates from the beginning in response to the horizontal load of the structure, the lower end of which is rotatably supported on a spherical surface, the upper end of which is supported to be able to slide up and down, and which operates after being horizontally displaced to a certain extent in response to the horizontal load of the structure. A seismic isolation device for structures characterized by being equipped with a steel rod damper.