JP2005030071A - Rolling vibration absorption bearing with attenuation function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling vibration absorption bearing with attenuation function capable of developing a high attenuation function as compared with conventional attenuation absorbing bearings and capable of miniaturizing the vibration absorbing plate. <P>SOLUTION: The bearing is provided with a spherical body 3 arranged between the lower side at the lower side vibration absorbing plate 1 fixed to a foundation 11 and the upper side vibration absorbing plate 2 fixed to the upper structure 12 and has both a rolling support function and an attenuation function damping a horizontal relative displacement between the upper structure 12 and the foundation 11 by sliding of the spherical body 3 at a large earthquake exceeding the rolling support function. The diameter of the lower side vibration absorbing plate 1 in plan view is formed larger than the diameter of the upper side vibration absorbing plate 2 in plan view, and a spherical body stopper 2b restricting the rolling motion of the spherical body 3 is provided at the outer peripheral part of the upper side vibration absorbing plate 2. Further, an inverted cone-shaped inclined face 1a having a gentle inclined face 1a1 on which the spherical body 3 rolls until the spherical body 3 gets into contact with the spherical body stopper 2b and an acute inclined face 1a2 on which the spherical body 3 prevented from rolling by the stopper 2b slides are provided at the lower side vibration absorbing plate 1. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  Rolling seismic isolation bearing with damping function that constitutes a seismic isolation device in combination with a damper supports the load of the upper structure and insulates the upper structure from the shaking of the ground during an earthquake. This rolling isolation bearing with a damping function is configured by placing a sphere between the lower isolation plate fixed to the foundation and the upper isolation plate fixed to the upper structure. A rolling bearing function that relatively displaces the structure and the foundation in the horizontal direction, and a damping function that attenuates the relative displacement in the horizontal direction between the upper structure and the foundation due to the sliding of the sphere during an unexpected large earthquake that exceeds the rolling bearing function. It is a device that has both. The present invention relates to a rolling seismic isolation bearing with a damping function.

  Conventionally, as this type of rolling isolation bearing with a damping function, a sliding bearing structure of a seismic isolation device described in Japanese Patent Laid-Open No. 10-292671 has been known, and this will be described with reference to FIGS. To do. 6 is a cross-sectional view of the sliding bearing structure of the seismic isolation device, and FIG. 7 is a diagram for explaining a single-ball rolling bearing state during an earthquake in the sliding bearing structure of FIG. FIG. 8 is a view for explaining a sliding support state during an earthquake in the sliding support structure of FIG.

  As shown in FIG. 6, the sliding support structure of the seismic isolation device includes a lower support plate (lower seismic isolation plate) 51 fixed to the foundation 61 and an upper structure facing the lower support plate 51. It has an upper support plate (upper seismic isolation plate) 53 fixed to the base of a building 62 for a general house. In addition, the upper support plate 53 and the lower support plate 51 are disposed between the upper support plate 53 and the lower support plate 51, and when the foundation 61 and the building 62 are relatively displaced in the horizontal direction. And one sphere (also called a ball) 55 that rolls against each other. The upper support plate 53 is substantially circular in a plan view having a lower surface 53a along a horizontal plane. The lower support plate 51 has a substantially circular shape in plan view, and a substantially mortar-shaped inclined surface 51a that approaches the upper support plate 53 as it goes outward from the center is formed on the upper surface thereof. Further, the planar view diameter d1 of the upper support plate 53 is formed larger than the planar view diameter d2 of the lower support plate 51.

  Furthermore, a lower peripheral wall 52 that restricts rolling of the sphere 55 with respect to the lower support plate 51 and prevents the lower support plate 51 from falling off is formed on the outer peripheral edge of the slope 51 a on the upper surface of the lower support plate 51. Has been. In addition, an upper peripheral wall 54 that prevents the spherical body from falling off from the upper support plate 53 is formed on the outer peripheral edge of the upper support plate 53. Note that the sphere 55 is normally at the lowest center portion of the lower support plate 51 as shown in FIG. 6, and the center of the sphere 55, the center of the upper support plate 53, and the center of the lower support plate 51 coincide. Yes.

  According to the sliding bearing structure configured as described above, when an earthquake occurs, the building 62 and the foundation 61 are relatively displaced in the horizontal direction from the normal state shown in FIG. In this case, the sphere 55 rolls with respect to each of the inclined surface 51 a of the lower support plate 51 and the lower surface 53 a of the upper support plate 53. Then, as shown in FIG. 7, the spherical body 55 is respectively against the lower support plate 51 on the foundation 61 side and the upper support plate 53 on the building 62 side until its rolling is restricted by the lower peripheral wall 52. Rolling.

  Therefore, the building 62 and the foundation 61 are relatively displaced in the horizontal direction by the rolling of the sphere 55, and are seismically isolated by rolling friction. The horizontal movement distance of the sphere 55 is half of the horizontal displacement of the superstructure. It becomes.

  When the sphere 55 comes into contact with the outer peripheral edge of the slope 51a of the lower support plate 51 due to the relative displacement in the horizontal direction between the building 62 and the foundation 61 due to an unexpected large earthquake, first, the sphere 55 rolls. Is restricted by the peripheral wall 16 and is prevented from falling off the lower support plate 51 of the sphere 55. Then, as shown in FIG. 8, the upper support plate 53 slides with respect to the sphere 55 in which this rolling is restricted, and eventually the upper support plate 53 is in a state of being stopped with respect to the lower support plate 51. The ball 55 is supported by sliding.

  The sliding friction coefficient (about 0.1) is 10 times or more of the rolling friction coefficient (0.01 or less) in the rolling support state, and the upper support plate 53 slides in contact with the sphere 55 so that the building 62 It becomes possible to attenuate the horizontal relative displacement with the foundation 61. That is, it is possible to reduce an excessive relative displacement between the building 62 and the foundation 61 by the sliding friction force, and until the spherical body 55 collides with the upper peripheral wall 54 of the upper support plate 53 having a larger planar view diameter. The relative displacement will be settled without reaching. As described above, the damping function is exhibited with respect to a large earthquake exceeding the rolling support function, and the horizontal relative displacement between the building 62 and the foundation 61 is attenuated.

However, in the sliding support structure of the seismic isolation device, when the foundation 61 and the building 62 are relatively displaced exceeding the rolling support function, the upper support plate is opposed to the sphere 55 whose rolling is restricted by the lower peripheral wall 52. Since the horizontal surface of the (upper seismic isolation plate) 53 is made to slide, and the seismic force is simply absorbed by the sliding frictional force on the horizontal surface, the upper support plate 53 is used to fully exhibit the damping function. It was necessary to increase the outer diameter of the. For this reason, the material cost of the upper side support board 53 became high, and there also existed a fault that the space | interval with an adjacent building needs to be enlarged.
JP-A-10-292671 (paragraph number [0009], FIGS. 1 to 3)

  Therefore, the present invention provides a rolling support function that relatively displaces the upper structure and the foundation in the horizontal direction by rolling of a sphere disposed between the upper and lower base plates during an earthquake, and an unexpectedly large function that exceeds the rolling support function. Rolling isolation bearings with a damping function that also has a damping function that attenuates relative displacement due to slip of a sphere during an earthquake can exhibit a higher damping function than before, and can reduce the size of the base isolation plate. The objective is to provide a seismic isolation bearing with a damping function.

  In order to solve the above problems, the present invention takes the following technical means. The invention of claim 1 is arranged between the lower base isolation plate fixed to the foundation, the upper base isolation plate fixed to the upper structure, and the upper and lower base isolation plates to load the upper structure. A rolling support function that relatively displaces the upper structure and the foundation in the horizontal direction by rolling of the sphere during an earthquake, and an upper part by sliding of the sphere in an unexpected large earthquake exceeding the rolling support function. In a rolling isolation bearing with a damping function that has a damping function that attenuates the relative displacement between the structure and the foundation in the horizontal direction, a lower seismic isolation plate fixed to the foundation and an upper seismic isolation fixed to the upper structure A rolling plate that is disposed between the upper and lower seismic isolation plates and supports the load of the upper structure, and that causes the upper structure and the foundation to be displaced relative to each other in the horizontal direction by the rolling of the ball during an earthquake. Assumed to exceed the support function and rolling support function In the rolling seismic isolation bearing with a damping function having a damping function for attenuating the horizontal relative displacement between the upper structure and the foundation by sliding of the sphere in the event of a large earthquake, the lower seismic isolation plate and the upper seismic isolation plate And a spherical stopper for preventing rolling of the sphere is provided on the outer peripheral portion of the other base isolation plate. On the other hand, the one base-isolated plate has a slope surface that rolls until the sphere contacts the sphere stopper of the other base-isolated plate, and a slope surface on which the sphere that is prevented from rolling by the sphere stopper slides. The mortar-shaped slope surface is provided.

  According to a second aspect of the present invention, in the rolling seismic isolation bearing with a damping function according to the first aspect, the inclined surface on which the sphere, which is prevented from rolling by the spherical stopper, slides until the spherical body abuts on the spherical stopper. It is characterized by being formed steeper than the slope surface.

  The invention according to claim 3 is the rolling seismic isolation bearing with a damping function according to claim 1 or 2, wherein the upper structure is a detached house building.

  The rolling seismic isolation bearing with a damping function according to the present invention provides a seismic isolation plate (for example, an upper seismic isolation plate fixed to an upper structure) of the lower seismic isolation plate and the upper seismic isolation plate in the event of a large earthquake. When the ball stopper comes into contact with the sphere stopper and its rolling is prevented, the sphere in contact with the other seismic isolation plate and prevented from rolling is not on the horizontal plane but on one seismic isolation plate (for example, the bottom fixed to the foundation). It is configured to slide diagonally upward on the slope surface of the side seismic isolation plate. As a result, according to the rolling seismic isolation bearing with a damping function of the present invention, the horizontal relative displacement between the upper structure and the foundation is attenuated compared to the conventional case for an unexpected large earthquake exceeding the rolling bearing function. Can be reduced. Therefore, it is possible to reduce the size of the one seismic isolation plate that generates sliding friction with the sphere, and the distance between adjacent buildings can be reduced as compared with the conventional structure. Can be expanded.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a seismic isolation bearing with a damping function according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG.

  As shown in FIGS. 1 and 2, the rolling seismic isolation bearing with a damping function is opposed to the lower seismic isolation dish 1 fixed to the foundation 11 by a plurality of bolts 4, and the lower seismic isolation dish 1. An upper seismic isolation plate 2 fixed by a plurality of bolts 5 to a base of a detached house building 12 as an upper structure is provided. Moreover, this rolling seismic isolation bearing with a damping function is disposed between the upper and lower seismic isolation plates 1 and 2 to support the load of the detached house building 12, and horizontally supports the detached house building 12 and the foundation 11 during an earthquake. A sphere 3 for relative displacement in the direction is provided.

  The upper seismic isolation plate 2 has a square outer shape, and is slightly obliquely downward from the center to the outer side on the surface facing the lower seismic isolation plate 1 (the lower surface opposite to the detached house building 12). It has an inverted mortar-shaped gradient surface 2a composed of a gentle gradient surface that extends while inclining. The inverted mortar-shaped gradient surface 2a has a circular shape (disc shape) in plan view. A spherical stopper 2 b that prevents rolling of the spherical body 3 is formed on the outer peripheral edge of the upper seismic isolation plate 2.

  The lower seismic isolation dish 1 has a square outer shape, and its planar view diameter d1 is larger than the planar view diameter d2 of the upper seismic isolation dish 2. The lower seismic isolation plate 1 is formed with a two-step gradient composed of a gentle slope surface 1a1 and a steep slope surface 1a2 on the surface facing the upper base isolation plate 2 (upper surface opposite to the foundation 11). It has a mortar-like sloped surface 1a. The gentle slope surface 1a1 has a circular shape (disc shape) in plan view, and the steep slope surface 1a2 has an annular shape in plan view. When there is no earthquake, the sphere 3 is at the center (lowest position) of the lower base plate 1, and the center position of the sphere 3, the center position of the lower base plate 1, and the center position of the upper base plate 2 are , Which coincide (see FIG. 2). In the lower base plate 1, the lower base plate 1 is slightly inclined obliquely upward from the center of the lower base plate 1 to a position corresponding to the outer peripheral edge of the inverted mortar-shaped slope surface 2 a of the upper base plate 2. A gentle gradient surface 1a1 extending while being inclined, and a steep gradient surface 1a2 extending outwardly from the gentle gradient surface 1a1 with a steeper slope than the gentle gradient surface 1a1.

  The upper seismic isolation plate 2 is made of, for example, carbon steel for machine structure and has a size of about 350 mm square. The lower seismic isolation plate 1 is made of, for example, carbon steel for machine structure and has a size of about 530 mm square. The spherical body 3 is made of, for example, bearing steel (SUJ2) and has an outer diameter of about 75 mm. In addition, the magnitude | size of the lower side seismic isolation plate 1 larger diameter than the upper side seismic isolation plate 2 is determined by the limit displacement of the detached house building 12 to build. The size of the upper seismic isolation plate 2 and the gradients 2a, 1a1, 1a2 are determined by the response performance of the seismic isolation device and the scale of the assumed earthquake.

  Next, the operation of the seismic isolation bearing with a damping function constructed as described above will be described with reference to FIGS. 2 and 3 to 5. 3-5 is sectional drawing for demonstrating operation | movement of the rolling seismic isolation bearing with a damping function shown in FIG.1 and FIG.2.

  When an earthquake occurs, as shown in FIG. 3, the spherical body 3 rolls with respect to the upper and lower seismic isolation plates 1, 2, so that the detached house building 12 and the foundation 11 are relatively displaced in the horizontal direction. In this case, the moving distance a in the horizontal direction of the sphere 3 is half of the horizontal displacement 2a of the detached house building 12 (upper seismic isolation plate 2). When the shaking stops, the lower seismic isolation plate 1 is formed with the gentle slope surface 1a1, and the upper seismic isolation plate 2 is formed with the inverted mortar-shaped slope surface 2a, so that the state shown in FIG. 2 is restored.

  When an unexpected large earthquake occurs, the sphere 3 is first brought into contact with the sphere stopper 2b of the upper seismic isolation plate 2 to prevent its rolling (see FIG. 4). Next, as shown in FIG. 5, the sphere 3 in a state of being in contact with the upper seismic isolation plate 2 and prevented from rolling is not on a horizontal plane, unlike the conventional case, but on the steeply inclined surface 1 a 2 of the lower seismic isolation plate 1. Glide up and down. As a result, as a damping force that attenuates and reduces the horizontal relative displacement between the detached house building 12 and the foundation 11, in addition to the sliding friction force, the sphere 3 that supports the load of the detached house building 12 is inclined upward. The moving force will also act.

  Thereby, according to the rolling seismic isolation bearing with a damping function according to the present embodiment, the horizontal relative displacement between the detached house building 12 and the foundation 11 is conventionally increased with respect to an unexpected large earthquake exceeding the rolling bearing function. It can be attenuated and reduced in comparison. Therefore, it is possible to reduce the size of the lower seismic isolation plate 1 that generates sliding friction with the sphere 3, and the distance between adjacent buildings can be reduced as compared with the conventional structure. The range can be expanded.

  In the above embodiment, the lower base isolation plate 1 is made larger than the upper base isolation plate 2, and the lower base isolation plate 1 is provided with a mortar-shaped slope surface having a gentle slope surface and a steep slope surface. The upper base isolation plate is made larger than the lower base isolation plate, and a mortar-shaped slope surface having a gentle slope surface and a steep slope surface is provided on the upper base isolation plate, and a spherical stopper is provided on the lower base isolation plate. By providing, the effect of this invention can be show | played similarly to the said embodiment.

  In addition, in this rolling seismic isolation bearing with a damping function, when an unexpected large earthquake that exceeds the rolling bearing function occurs and the shaking stops, the sphere 3 is seismically isolated from either the upper or lower seismic isolation trays 1 or 2. Although returning to the center of the plate, there is a possibility that the detached house building 12 is displaced from the original position by the amount of sliding displacement. In this case, once it is necessary to jack up the detached house building 12 and return it to its original position, such work is necessary due to appropriate design. It can be limited to detached houses in soft ground areas close to the epicenter of an unexpected large earthquake.

  The rolling seismic isolation bearing with a damping function according to the present invention constitutes a seismic isolation device in combination with a damper and can be applied to a lightweight structure such as a detached house building.

It is a top view of the rolling seismic isolation bearing with a damping function by one embodiment of the present invention. It is the sectional view on the AA line of FIG. It is sectional drawing for demonstrating operation | movement of the rolling seismic isolation bearing with a damping function shown in FIG.1 and FIG.2. It is sectional drawing for demonstrating operation | movement of the rolling seismic isolation bearing with a damping function shown in FIG.1 and FIG.2. It is sectional drawing for demonstrating operation | movement of the rolling seismic isolation bearing with a damping function shown in FIG.1 and FIG.2. It is sectional drawing of the sliding bearing structure of a seismic isolation apparatus which shows a prior art. It is a figure for demonstrating the single-ball rolling support state at the time of an earthquake in the sliding support structure of FIG. FIG. 7 is a view for explaining a sliding bearing state at the time of an earthquake in the sliding bearing structure of FIG. 6.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Lower seismic isolation plate 1a ... Mortar-shaped gradient surface 1a1 ... Slow gradient surface 1a2 ... Steep gradient surface 2 ... Upper seismic isolation plate 2a ... Reverse mortar-shaped gradient surface 2b ... Sphere stopper 3 ... Sphere 4 ... Bolt 5 ... Bolt 11 ... foundation 12 ... detached house building

Claims (3)

A lower seismic isolation plate fixed to the foundation, an upper seismic isolation plate fixed to the upper structure, and a sphere arranged between the upper and lower seismic isolation plates to support the load of the upper structure, Rolling bearing function that relatively displaces the upper structure and the foundation in the horizontal direction by rolling the sphere during an earthquake, and horizontal displacement between the upper structure and the foundation due to slipping of the sphere during an unexpected large earthquake exceeding the rolling bearing function. In a rolling seismic isolation bearing with a damping function that also has a damping function to attenuate the relative displacement in the direction,
A planar view diameter of one of the lower isolation plate and the upper isolation plate is formed to be larger than a planar view diameter of the other isolation plate, and While providing a spherical stopper for preventing the rolling of the spherical body, the one base-isolated dish is provided with a sloped surface that rolls until the spherical body comes into contact with the spherical stopper of the other base-isolated dish and the spherical stopper. A rolling seismic isolation bearing with a damping function, characterized in that it has a mortar-shaped gradient surface having a gradient surface on which a sphere prevented from rolling slides.   The gradient surface on which a sphere that is prevented from rolling by the sphere stopper slides is steeper than the gradient surface that rolls until the sphere abuts the sphere stopper. Rolling seismic isolation bearing with damping function. 3. The rolling seismic isolation bearing with a damping function according to claim 1, wherein the upper structure is a detached house building.