JP5535151B2 - Seismic isolation device and seismic isolation structure using the seismic isolation device - Google Patents

Description

  The present invention relates to a seismic isolation state canceling apparatus and a seismic isolation state used for canceling the previous seismic isolation state when a long-period earthquake motion exceeding a predetermined period occurs with respect to the seismic isolation structure. It relates to a seismic isolation structure using a release device.

  As is well known, the types of seismic isolation devices that have been provided so far to protect structures from vibrations caused by earthquakes include, for example, (1) laminated rubber with laminated rubber plates (or an iron plate interposed therebetween) Proposals include those that support the upper structure from below (laminated rubber seismic isolation), (2) those that absorb the vibration caused by the earthquake with a damper device, and (3) those that insulate between the ground and the upper structure. ing. For example, as the insulation method of (3) above, a method of floating the upper structure with liquid or magnetic force, a method of sliding the ground and the upper structure (sliding bearing or sliding seismic isolation), a roll bearing, etc. Some have been proposed to roll the sphere (rolling seismic isolation), and some have been put into practical use. Further, as a conventional seismic isolation device or seismic isolation structure, a combination of the above-described device (1) or structure with the device (3) or structure has been proposed. Therefore, by adopting these seismic isolation devices or seismic isolation structures, it is possible to protect the structure from earthquake vibrations and avoid damage caused by earthquakes.

  By the way, even if each of the above-mentioned seismic isolation devices or seismic isolation structures is adopted, it is practically impossible to have a structure that can cope with the scale or degree of any earthquake. For example, in the case of the seismic isolation device or seismic isolation structure using the so-called laminated rubber of (1) described above, to what extent the relative displacement length between the ground side and the structure side due to the earthquake is allowed. (Maximum allowable range) is a matter of course to be determined in the design. The length of the diameter of the upper surface or the lower surface of the member forming the sliding surface to be determined in the case of adopting the above-described seismic isolation device or seismic isolation structure referred to as so-called sliding bearing or sliding isolation is the amplitude stroke. If the seismic isolation function is always expected to be effective even when the length is long, it is theoretically sufficient to set the diameter accordingly, but the site area of the building is usually limited, and the building adjacent to the building to be constructed In consideration of the distance to the ridge and other structures, it is practically impossible to make the diameter unlimited. This is the same in the case of adopting the seismic isolation device or structure referred to as the so-called roller seismic isolation described above, and the lower support plate fixed to the ground side or the upper support plate fixed to the structure side. It is practically impossible to increase the area without limitation even from the viewpoint of cost. Therefore, the seismic isolation device or seismic isolation structure that is specifically adopted provides a certain range or limit to the amplitude stroke that allows seismic isolation, depending on the site area of the building to be constructed and the surrounding environment, etc. When an earthquake (long-period ground motion) with an amplitude stroke exceeding the range or limit occurs, the seismic isolation device is destroyed, or the superstructure that has been supported until then cannot be supported. It is necessary to provide a structure or a device for avoiding a situation in which only a predetermined member falls off (a technique having a so-called fail-safe function is required).

  In view of this, a structure having the fail-safe function is provided in consideration of the occurrence of an earthquake having an amplitude stroke larger than the range or limit, by providing a certain range or limit to the amplitude stroke that can be seismically isolated. Separately from seismic isolation devices and seismic isolation devices, devices having such a fail-safe function have been proposed. For example, the seismic isolation device described in Japanese Patent Application Laid-Open No. 6-158912 (Patent Document 1) stands up from the outer periphery of the upper surface of the lower support plate (sphere case 1B) and the outer periphery of the lower surface of the upper support plate (sphere case 1A). A stopper portion (inner wall 10) is formed, and a number of tension springs 6 are provided which restrict relative horizontal movement of the lower support plate and the upper support plate within a certain range. It is said that. According to this seismic isolation device, the lower support plate and the upper support plate start to move relative to each other through the rolling of the sphere provided therebetween due to the vibration of the earthquake, and the sphere reaches the stopper portion eventually. Further, the horizontal movement of the lower support plate and the upper support plate is restricted by the stopper portion. In addition, the horizontal movement of the lower and upper support plates is also restricted by the elastic force of the numerous tension springs, and the tension springs are restored so that the seismic isolation device returns to the state before the occurrence of the earthquake. It also acts as a force. In addition, as described above, as a device that limits the seismic isolation effect when a certain range or limit is set in the amplitude stroke of an earthquake that can be isolated, and an earthquake having an amplitude stroke greater than that range or limit occurs. In addition, there has been proposed a damper or stopper provided at a position away from the position where the seismic isolation device is installed. As for the damper, like the steel rod damper disclosed in Japanese Utility Model Publication No. 7-23442 (Patent Document 2), the steel rod 5 is subjected to deformation such as bending and twisting with respect to shaking in all directions due to an earthquake. There are some that absorb the vibration and shock caused by the earthquake by the restoring force obtained. A viscous damper typified by an oil damper includes a cylinder and a piston, and absorbs vibrations and shocks caused by an earthquake by viscous resistance when fluid in the cylinder passes through an orifice provided in the piston. .

JP-A-6-158912 No. 7-23442

  However, in the seismic isolation device disclosed in Patent Document 1 described above, when an earthquake with an amplitude stroke exceeding the seismic isolation possible range (long-period ground motion) occurs, the sphere collides with the stopper, and the impact Every time a large impact force and impact sound are repeatedly generated, the structure is further destroyed. In addition, this seismic isolation device has the effect of restricting the relative horizontal movement of the lower and upper support plates by a number of tension springs, but how to set the elastic modulus of the tension springs is a technology. This is difficult, and the replacement work is time-consuming. Further, in the steel rod damper disclosed in Patent Document 2, when an earthquake is strong and the amplitude stroke of the ground is large, residual deformation remains in the steel rod, and it is necessary to replace it every time an earthquake occurs. Become. In addition, when a viscous damper is provided, it must respond to earthquake motions in all directions. In other words, when such dampers are used, for example, four dampers are required in total even if one is installed in each of east, west, north, and south. Considering this, it is necessary to install an extremely large number of structures, and the construction period is greatly extended and the cost is high. Is difficult to adopt in reality.

  In addition, the above-described devices and structures described above are structured when the ground side swings in a specific direction and the swing width is equal to or greater than a preset seismic isolation length (when long-period ground motion). Since the side member and the ground side member collide with each other (slowly in some cases), the ground side sways in a specific direction (for example, the positive direction of X), and then collided or contacted. Immediately after swinging in the same direction as it is, if the ground side swings in the opposite direction to the previous direction (the negative direction of X), the structure (especially if it is based on a wooden or shaft construction method) The object bends, and after the upper side of the structure is further moved in the positive direction of X, it moves in the negative direction of X (in other words, so that the whip returns). Similarly, in the minus direction of X, the process moves in the plus direction of X while performing the above-described process (so that the whip returns). In other words, in the case of long-period ground motion whose deflection width is equal to or greater than the pre-set seismic isolation length, the period is greatly amplified in combination with the deflection of the entire structure, resulting in greater damage. There is.

  Therefore, the present invention has been proposed in order to solve the various problems of the conventional seismic isolation device or the damper described above, and has a certain range or limit in the earthquake amplitude stroke that can be handled. Even if an earthquake with an amplitude stroke exceeding the range or limit occurs for a seismic structure, the seismic isolation device can be prevented from being damaged and has the above fail-safe functions. Rather, it is possible to effectively reduce the generation of large impact force and impact sound due to earthquake vibrations, and to reduce the influence on the superstructure, and this seismic isolation state cancellation device and this isolation mode The object is to provide a seismic isolation structure using a release device.

The present invention has been proposed in order to solve the above problems, and the first invention (the invention according to claim 1) is arranged in a seismic isolation structure that is seismically isolated by a seismic isolation device. A shaft support member that is fixed from the seismic isolation structure side toward the ground side and has a shaft insertion space formed in the vertical direction therein, and is inserted into the shaft insertion space formed in the shaft support member. A shaft-shaped member, a disk-shaped sliding contact plate that is fixed horizontally below the shaft-shaped member, and that normally supports the shaft-shaped member from below on the upper surface, and the sliding contact plate A ring space fixed between the ring member and the sliding contact plate and the ring member is formed, and a drop space is formed between the sliding member plate and the ring member. The seismic isolation state due to is canceled.

The seismic isolation state canceling device according to the first invention is arranged in a seismic isolation structure that is seismically isolated by the seismic isolation device. This seismic isolation device can use (1) laminated rubber seismic isolation, or (3) sliding bearing or sliding seismic isolation or roller seismic isolation as described above as a single unit or in combination. And according to the seismic isolation state cancellation apparatus concerning this 1st invention, when the vibration by an earthquake generate | occur | produces and a structure and the ground displace relatively, the lower end of the said shaft-shaped member will be the upper surface of the said sliding contact plate Reciprocates while sliding. When a long-period earthquake with a large displacement occurs (the sliding contact plate (ground side) moves over a distance longer than the radius of the sliding contact plate), the shaft-shaped member It reaches the fall space formed between the ring member and falls while being supported by the shaft support member, and the seismic isolation state (of the seismic isolation structure) by the seismic isolation device is released until then. That is, the seismic isolation structure moves (vibrates) along with the movement (vibration) of the ground. In addition to the case where the shaft-shaped member falls due to its own weight, for example, an elastic material that presses the shaft-shaped member downward is disposed above the shaft-shaped member, and the elasticity of the elastic material A structure that falls by force may be adopted.

Therefore, according to the seismic isolation state canceling apparatus according to the first aspect of the present invention, the seismic isolation structure having a certain range or limit in the amplitude stroke of the earthquake that can be handled has an amplitude stroke exceeding the range or limit. Even if an earthquake occurs, it not only has a fail-safe function such as preventing the seismic isolation device from being damaged, but also effectively reduces the generation of large impact force and impact sound due to earthquake vibration. In addition , the influence on the seismic isolation structure can be reduced. In other words, according to the first invention, as described above, the seismic isolation structure is greatly displaced and shaken while maintaining the seismic isolation function (so that the whip returns). It is possible to effectively prevent the occurrence of a large damage (than the damage caused when the base isolation structure is shaken together with the ground without base isolation ).

  The second invention (the invention described in claim 2) is characterized in that, in the first invention, the height of the ring member is made higher than the height of the sliding contact plate. is there.

  In the seismic isolation state canceling device according to the second aspect of the present invention, since the height of the ring member is higher than the height of the sliding contact plate, the shaft-shaped member drops as the ground side moves. The risk of jumping over the ring member without falling into the space can be effectively prevented.

  In addition, according to a third invention (invention according to claim 3), in any one of the first and second inventions, either one or both of the shaft support member and the shaft-shaped member may include the shaft-shaped member. The holding means for holding the lower surface of the member at a position above the upper surface of the sliding contact plate is formed.

Since the holding means is formed in the seismic isolation state canceling apparatus according to the third aspect of the present invention, after the shaft-shaped member has fallen into the falling space, the seismic isolation structure is not equipped with a mechanical instrument such as a jack. When the work is returned to its original position, for example, the shaft-like member is moved horizontally so that the shaft-like member is located at the center of the sliding contact plate, the operator keeps the shaft-like member from falling down constantly. Can be eliminated and work efficiency can be improved.

  The holding means may be any means as long as it can hold at least the lower surface of the shaft-like member at a position higher than the upper surface of the sliding contact plate, and the means includes the shaft support member and the shaft-like member. What is necessary is just to be arrange | positioned or formed in any one or both.

A fourth invention (invention according to claim 4) is a seismic isolation structure comprising the seismic isolation state canceling device according to any one of the first, second or third inventions, wherein The shaft support member in which the shaft insertion space is formed in the vertical direction is fixed from the seismic isolation structure side to the ground side, and the shaft-like member is inserted into the shaft insertion space formed in the shaft support member. Under this shaft-like member, a disk-like sliding contact plate that supports the shaft-like member from below is normally fixed horizontally on the upper surface, and on the outer peripheral side of this sliding contact plate, A ring member is fixed, and a drop space is formed between the sliding plate and the ring member to drop the shaft-like member. Is released.

  Even in the case of the seismic isolation structure according to the fourth invention, the same operational effects as the first invention can be obtained.

According to the seismic isolation state canceling device according to the first invention (the invention according to claim 1) and the seismic isolation structure according to the fourth invention, there is a certain range or limit in the amplitude stroke of the earthquake that can be handled. Not only does it have a fail-safe function, such as preventing damage to the seismic isolation device, even if an earthquake with an amplitude stroke exceeding the range or limit occurs for the seismic isolation structure. In addition, it is possible to effectively reduce the generation of large impact force and impact sound due to earthquake vibrations, and to reduce the influence on the seismic isolation structure. In other words, according to the first invention, as described above, the seismic isolation structure is greatly displaced and shaken while maintaining the seismic isolation function (so that the whip returns). It is possible to effectively prevent the occurrence of a large damage (than the damage caused when the base isolation structure is shaken together with the ground without base isolation ).

  Further, according to the seismic isolation state canceling device according to the second invention (the invention described in claim 2), the risk that the shaft-shaped member does not fall into the falling space and jumps over the ring member with the movement of the ground side. It is possible to effectively prevent sex.

According to a third aspect of the invention (invention of claim 3), after the shaft-shaped member has fallen into the drop space, the seismic isolation structure is raised using a machine such as a jack, and the shaft When the work is returned to its original position, such as horizontally moving so that the shaped member is positioned at the center of the sliding contact plate, it becomes unnecessary to keep the shaft-like member from falling down constantly so that the work efficiency is improved. be able to.

It is a side view which shows typically the state by which the seismic isolation state cancellation | release apparatus is arrange | positioned at the seismic isolation structure. It is a disassembled perspective view which shows the main structures of the seismic isolation state cancellation | release apparatus shown in FIG. It is a side view which expands and shows the seismic isolation state cancellation | release apparatus shown in FIG. It is a top view which expands and shows the seismic isolation state cancellation | release apparatus shown in FIG. It is a top view which shows typically the state after the ground is displaced to the left side in a figure with respect to a seismic isolation structure. It is a top view which shows typically the state after the ground is displaced to the right side in a figure with respect to a seismic isolation structure. It is a top view which shows typically the state after the ground is displaced to the lower side in a figure with respect to a seismic isolation structure. It is a top view which shows typically the state after the ground is displaced to the upper side in a figure with respect to a seismic isolation structure. It is sectional drawing which shows the state which the shaft-shaped member fell in fall space.

  EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the seismic isolation state cancellation | release apparatus of the seismic isolation structure which concerns on this invention, and the seismic isolation structure provided with this seismic isolation state cancellation | release apparatus is demonstrated in detail, referring drawings. First, the base isolation structure of the base isolation structure will be briefly described, and then the base isolation control device used for the base isolation structure will be described in detail.

  As shown in FIG. 1, this seismic isolation structure is a first seismic isolation device between foundation concrete (hereinafter sometimes referred to as the ground) 1 and a base 3 constituting the seismic isolation structure 2. 4 and the second seismic isolation device 5 are arranged. The first seismic isolation device 4 includes a lower disk plate 8 fixed on a first support plate 7 provided horizontally on the upper surface of the foundation concrete 1, and an upper part having the same shape as the lower disk plate 8. It is composed of a disk plate 9 and a cylindrical laminated body 10 sandwiched between a plurality of disk-shaped rubbers (not shown) sandwiched between the lower disk plate 8 and the upper disk plate 9. In this example, a fixing member 11 is fixed to the lower surface of the base 3, and the upper disk plate 9 is composed of bolts and nuts (not shown) with respect to the fixing plate 12 fixed to the lower surface of the fixing member 11. It is fixed by a plurality of fasteners.

  The second seismic isolation device 5 is formed on the foundation concrete 1 and has a support plate 14 whose upper surface is a smooth sliding surface, and an upper end fixed to the lower surface of the base 3 and is suspended from the base 3. And a slider 15 formed as described above. The support plate 14 is formed in a disk shape, and a lubricant such as a fluorine resin (not shown) is applied to the upper surface. The lower surface of the slider 15 is placed on the upper surface of the support plate 14, and is configured to come into sliding contact with the support plate when an earthquake motion occurs. A plurality of the first and second seismic isolation devices 4 and 5 are arranged, respectively, and the load of the entire seismic isolation structure 2 is supported by the first and second seismic isolation devices 4 and 5. Yes. Therefore, when the ground side vibrates due to the occurrence of an earthquake, the acceleration is greatly attenuated and transmitted to the seismic isolation structure 2 side (ie, seismic isolation).

  And on the said foundation concrete 1, the seismic isolation state cancellation | release apparatus 21 which concerns on this invention is arrange | positioned. As shown in FIG. 1 or FIG. 2, the seismic isolation state canceling device 21 according to this embodiment is fixed at the center of the upper surface of the fixing plate 22 and the fixing plate 22 fixed horizontally on the foundation concrete 1. And a slidable contact plate 23 formed in a disc shape, and a ring member 24 fixed on the fixed plate 2 and outside the slidable contact plate 23. The fixing plate 22 is an iron plate formed in a square shape, and a shaft of a bolt (not shown) that is screwed to a nut (not shown) embedded in the surface of the foundation concrete 1 is inserted into the outer peripheral side end. A plurality of through holes 22a are formed. The sliding contact plate 23 is also formed into a disk shape from a metal material such as iron or stainless steel, and is fixed to the center of the fixing plate 22 by fixing means such as welding. The diameter of the sliding contact plate 23 is substantially the same as or slightly shorter than the diameter of the support plate 14.

  The ring member 24 fixed to the outer peripheral side of the sliding contact plate 23 is formed in a ring shape from a metal material such as iron or stainless steel, and is fixed to the fixed plate 22 by welding or the like. It is fixed by means. Further, as shown in FIG. 1, the ring member 24 has a height higher than that of the sliding contact plate 23. A space between the ring member 24 and the sliding contact plate 23 is a drop space 26 in which a shaft-like member 27 described later falls.

  On the other hand, as shown in FIG. 1, a shaft support member 28 is fixed downward on the lower surface of the base 3, and a shaft-like member 27 is inserted into the shaft support member 28 from the lower side to the upper side. The lower end of the shaft-shaped member 27 abuts against the center (center) of the sliding contact plate 23 by its own weight, and most of the load of the shaft-shaped member 27 is supported by the sliding contact plate 23. ing. As shown in FIG. 2, the shaft support member 28 includes a fixed plate portion 30 fixed to the lower surface of the base 3, a circular opening 30a formed at the center of the fixed plate portion 30, and the fixed plate. Reinforcement that is welded to the cylindrical portion 31 that hangs down from the lower surface of the portion 30, the outer periphery of the cylindrical portion 31, and the lower surface of the fixed plate portion 30, and is arranged radially from the outer peripheral surface of the cylindrical portion 31. The rib 32 is comprised. Bolts 34 (axes) used for fixing the fixing plate 30 to the lower surface of the base 3 are provided on the fixing plate 30 that does not correspond to the portion where the reinforcing rib 32 is welded. A total of eight through-holes 30b are formed through which are inserted. Further, the cylindrical portion 31 has an inner diameter slightly longer than the diameter of the shaft-shaped member 27 since the shaft-shaped member 27 is inserted therethrough. Further, as shown in FIG. 3, the cylindrical portion 31 is formed with a linear notch 31a having a length from the upper end to the lower end side, and an intermediate portion on the upper end side of the linear notch 31a. Are respectively formed with arc-shaped notches 31b that communicate with the linear notches 31a and have a length in the circumferential direction of the cylindrical portion 31. At the same time, the fixing plate 30 is also formed with a notch 30c into which a locking projection 27a described later is inserted (see FIG. 4).

  On the other hand, the shaft-shaped member 27 is formed in a cylindrical shape from a metal material such as iron or stainless steel, and is inserted into the cylindrical portion 31 from above as shown in FIG. A locking convex portion 27a is projected in the horizontal direction on the outer peripheral surface of the middle portion on the upper end side. The outer diameter of the locking projection 27a is such that it is inserted through both the linear notch 31a and the arc-shaped notch 31b, and as shown in FIG. Further, it is inserted in the middle of the linear notch 31a at a position lower than the position where the arc-shaped notch 31b is formed.

  Hereinafter, the effect of the seismic isolation structure 2 provided with the seismic isolation state cancellation device 21 according to the above-described configuration, that is, the effect when an earthquake occurs will be described.

  First, as shown in FIG. 1, in the state where the first and second seismic isolation devices 4 and 5 are arranged and the shaft-like member 27 is located at the center of the sliding plate 23, the earthquake is not a long cycle. In other words, when the earthquake occurs (that is, the earthquake that moves on the sliding plate 23 and the slider 15 moves on the support plate 14 that constitutes the second seismic isolation device 5), the first still remains. The second seismic isolation devices 4 and 5 bring the seismic isolation structure 2 into a seismic isolation state.

  However, when the earthquake is long-period vibration, the ground (foundation concrete) 1 side is greatly displaced from the structure 2 and, for example, as shown in FIG. 5, the left side in the figure (arrow side in FIG. 5). Is displaced to the left, the support plate 14 moves to the left. As a result, the slider 15 constituting the second seismic isolation device 5 fixed to the seismic isolation structure 2 side is located on the right side of the support plate 14 and the stage before the slider 15 falls off the support plate 14. The shaft-like member 27 moves on the fall space 26 described above. Thus, when the shaft-like member 27 moves, the shaft-like member 27 falls between the sliding contact plate 23 and the ring member 24 due to its own weight (see FIG. 9), so that the ground 1 side further moves. Then, the structure 2 also follows and moves, and the structure 2 also follows when the ground 1 moves in the opposite direction. That is, the seismic isolation structure 2 that has been in the seismic isolation state until then is released from the seismic isolation state and becomes a non-base isolation structure. 6, when the ground 1 moves to the right side as shown in FIG. 6, when the ground 1 moves down in the figure as shown in FIG. 7, as shown in FIG. 8, The same applies when the ground 1 moves upward.

  Therefore, according to the seismic isolation state cancellation device 21 and the seismic isolation structure 2 provided with the seismic isolation state cancellation device 21 according to this embodiment, the first seismic isolation device 4 or the second seismic isolation device 5 is provided. Fail-safe function, such as preventing the seismic isolation devices 4 and 5 from being damaged even when an earthquake with an amplitude stroke exceeding the seismic isolation possible due to earthquake (long-period ground motion) occurs. In addition to having a large impact force, it is possible to effectively reduce the generation of large impact force and impact sound due to earthquake vibrations, and to reduce the influence on the structure 2. In other words, according to this seismic isolation structure, as described above, while maintaining the seismic isolation function, the structure 2 is greatly displaced and shaken (so that the whip returns), It is possible to effectively prevent the occurrence of a large damage (as compared to the damage caused when the structure is shaken together with the ground without seismic isolation).

  In particular, in the seismic isolation state canceling device 21, since the height of the ring member 24 is higher than the height of the sliding contact plate 23, the shaft-shaped member 27 does not fall into the drop space 26, The risk of moving over the ring member 24 to the outside of the ring member 24 can be effectively prevented.

  Further, in the seismic isolation state canceling device 21, the cylindrical notch 31a and the arc-shaped notch 31b are formed on the cylindrical part 31 constituting the shaft support member 28 as described above. Since the locking protrusion 27a is inserted into the linear notch 31a, the seismic isolation state until then is generated as shown in FIG. Is released, and then the earthquake ends, and when returning the structure 2 to the original state as shown in FIG. The operator can raise the cylindrical member 27, and the locking convex portion 27a can be inserted and locked into the arc-shaped cutout 31b. The locking member 27a of the shaft-like member 27 is thus locked to the arc-shaped cutout 31b, so that the shaft-like member 27 can be kept in the raised state. Therefore, the structure 2 is shown in FIG. Thus, the operation of returning to the state shown in FIG. 1 can be performed very efficiently.

  The cylindrical part 31 is formed with a linear notch 31a and an arcuate notch 31b communicating with each other, and the locking convex part 27a inserted into the linear notch 31a is provided. The configuration in which the shaft-shaped member 27 is held at a predetermined position by being inserted through the notch 31b on the arc is configured as “holding the lower surface of the shaft-shaped member at a position higher than the upper surface of the sliding plate”. Holding means ”. Therefore, in the seismic isolation state canceling device 21 according to the above-described embodiment, the holding means is provided with both the shaft-like member 27 and the shaft support member 28, and they are jointly operated as “the lower surface of the shaft-like member. Is held at a position above the upper surface of the sliding contact plate ”. However, the structure as such holding means is provided only on the shaft-shaped member 27 or only on the shaft support member 28. May be.

DESCRIPTION OF SYMBOLS 1 (Foundation concrete) Ground 2 Seismic isolation structure 4 1st seismic isolation device 5 2nd seismic isolation device 21 Seismic isolation state cancellation device 23 Sliding contact plate 24 Ring member 26 Fall space 27 Shaft-shaped member 27a Convex protrusion Part 28 Shaft support member 31a Straight cutout 31b Arc cutout

Claims (4)

A shaft support that is arranged in a seismic isolation structure that is seismically isolated by a seismic isolation device, and is fixed from the seismic isolation structure side to the ground side, and a shaft insertion space is formed in the vertical direction inside. Members,
A shaft-like member inserted into a shaft insertion space formed in the shaft support member;
A disc-shaped sliding contact plate that is horizontally fixed below the shaft-shaped member and that supports the shaft-shaped member from below on the upper surface in a normal state.
A ring member fixed to the outer peripheral side of the sliding plate;
A fall space is formed between the sliding plate and the ring member, and the shaft-like member falls, and the seismic isolation state by the seismic isolation device is released when the shaft-like member falls. Seismic isolation release device.   The seismic isolation state canceling device according to claim 1, wherein a height of the ring member is higher than a height of the sliding contact plate.   One or both of the shaft support member and the shaft-shaped member are formed with holding means for holding the lower surface of the shaft-shaped member at a position above the upper surface of the sliding contact plate. The seismic isolation state cancellation device according to claim 1. In the seismic isolation structure provided with the seismic isolation state release device, the shaft support member in which the shaft insertion space is formed in the vertical direction is fixed toward the ground side from the seismic isolation structure side,
In the shaft insertion space formed in this shaft support member, a shaft member is inserted,
Under this shaft-like member, a disk-like sliding contact plate that supports the shaft-like member from below is normally fixed horizontally on the upper surface,
A ring member is fixed to the outer peripheral side of this sliding contact plate,
A fall space is formed between the sliding plate and the ring member, and the shaft-like member falls, and the seismic isolation state by the seismic isolation device is released when the shaft-like member falls. A seismic isolation structure comprising the seismic isolation state canceling device according to claim 1 .