JP7783019B2 - seismic control device - Google Patents

Description

The present invention relates to a vibration control device.

Conventionally, bearings and damper components (see Patent Document 1 below) installed in seismically isolated buildings have a limit deformation as a device. They are generally designed to be below the performance-guaranteed deformation for so-called Level 2 earthquake motion as determined by public notice, or below the limit deformation for an earthquake approximately 1.5 times Level 2 as a margin of error set for each project, or below the seismic isolation clearance.

On the other hand, in recent years, there have been extremely large earthquakes exceeding 1.5 times the level 2 level, and external forces beyond the design assumptions may act, causing these limit deformations to be exceeded. Therefore, there is a need for fail-safe devices that suppress deformation below the limit deformation or seismic isolation clearance so that the seismic isolation layer can remain sound even in the event of earthquake motions that exceed assumptions.
Furthermore, there is a need for wind-resistant locking devices to prevent deformation of the seismic isolation layer from the perspective of ensuring livability and elevator operation due to wind loads.

Japanese Patent Application Laid-Open No. 2007-231601

In addition, there is an increase in buildings where elevators and other structures penetrate the seismic isolation layer, such as mid-story seismic isolation buildings. In such cases, residual deformation of the seismic isolation layer after an earthquake is an issue, and there is a demand for devices that can instantly restore the structure from a state where residual deformation exists.
Furthermore, there is a demand for a vibration control device that can cope not only with earthquake motions that are beyond the design assumptions, such as those exceeding 1.5 times Lv2, but also with earthquake motions that exceed Lv2 but are not so unexpected (for example, Lv2 x 1.0 to Lv2 x 1.5, equivalent to Lv3).
There is also the issue that if the seismic isolation layer is deformed during strong winds, it can cause problems with elevator operation, so there is a need for devices that can fix the seismic isolation layer or limit deformation due to wind loads.

The present invention was made in consideration of the above circumstances, and provides a seismic control device that can absorb more energy before reaching critical deformation, functions as a jack to restore residual deformation, and can fixate the seismic isolation layer or limit deformation.

In order to achieve the above object, the present invention employs the following means.
In other words, the seismic control device of the present invention is a seismic control device installed in a seismic isolation layer between the structures of a building, and comprises a tension member connected between the structures of the building, a stopper mechanism provided on the tension member, a jack through which the tension member passes, and a displacement following member that is attached to the jack and is attached to the structure of the building so that it can rotate around an axis with the vertical direction as the axial direction, and that causes the tension member to follow the displacement of the seismic isolation layer; under normal circumstances, the jack is in a state where the cylinder is extended, and during an earthquake, the cylinder abuts against the stopper mechanism and the cylinder is compressed.

In a seismic control device configured in this way, when the tensile force increases, the jack cylinder comes into contact with the stopper mechanism and is compressed. The cylinder's extension length disappears, and the jack functions as an oil buffer, absorbing energy. When the tensile force increases further and the cylinder is further compressed, the tension member comes into play and absorbs energy. This allows for greater energy absorption before the limit deformation is reached. It also functions as a jack, allowing residual deformation to be restored, and it is possible to fix the seismic isolation layer or limit deformation.

Furthermore, in the vibration control device according to the present invention, when the cylinder of the jack is compressed during an earthquake, either the relief valve or the orifice may be activated.

In a seismic control device configured in this way, when the cylinder of the jack is compressed during an earthquake, either the relief valve or the orifice is activated, causing the oil inside the jack to be discharged, providing viscous damping resistance and absorbing energy.

Furthermore, the seismic control device according to the present invention may be configured to close the valve in the pipeline leading to either the relief valve or the orifice after an earthquake.

With a seismic control device configured in this way, after an earthquake, the valve in the pipeline leading to either the relief valve or the orifice can be closed, allowing residual deformation to return to normal. During strong winds, the jack cylinder can be extended until it abuts the stopper, closing the valve in the pipeline leading to either the relief valve or the orifice, or fixing the seismic isolation layer within a range below the load acting on the relief valve.

The seismic control device of the present invention can absorb more energy before reaching its limit deformation. In addition, it can restore residual deformation of the seismic isolation layer caused by earthquakes or wind loads. Furthermore, it can fix the seismic isolation layer so that it does not deform due to wind loads during strong winds.

1 is a side view showing the configuration of a vibration damping device according to an embodiment of the present invention. 1 is a plan view showing the configuration of a vibration damping device according to an embodiment of the present invention. FIG. 3 is an enlarged view of part III in FIG. 2 . 1 shows the configuration of a seismic control device according to one embodiment of the present invention in a state in which the seismic isolation layer is fixed during strong winds. FIG. 1 is an image diagram of the restoring force characteristics of a two-stage seismic isolation fail-safe of a seismic damping device according to one embodiment of the present invention. (a) is a plan view showing the displacement of the vibration control device when a compressive force acts on one embodiment of the present invention and the vibration control damper is displaced in two directions, and (b) is a plan view showing the displacement of the seismic isolation rubber. (a) is a plan view showing the displacement of the vibration control device when a tensile force acts on one embodiment of the vibration control device of the present invention, causing the vibration control damper to displace in two directions, and (b) is a plan view showing the displacement of the seismic isolation rubber. 1A and 1B are plan views showing the state in which the jack of the seismic control device of one embodiment of the present invention is jacked up, and FIG. 1B is a plan view showing the displacement of the seismic isolation rubber. 1 is a schematic diagram of a jack of a seismic damping device according to one embodiment of the present invention, when a relief valve and a tank are used in the jack during jacking up. FIG. FIG. 10 is a schematic diagram of a seismic damping device according to an embodiment of the present invention, in which an orifice is used in the jack, when jacked up, and shows a case in which there is no waste oil tank. 1 is a schematic diagram of a jack-up state when a relief valve is used in a jack of a seismic damping device according to one embodiment of the present invention. FIG. 10 is an analysis result of a comparison of response deformation during a maximum earthquake (Lv2 x 2.0 times) using a seismic damping device according to one embodiment of the present invention, showing the response story deformation. 10 is an analysis result of a comparison of response deformation during a maximum earthquake (Lv2 x 2.0 times) using a seismic damping device according to one embodiment of the present invention, showing response acceleration. 10 is an analysis result of a response deformation comparison (Lv2 x 1.5 times) using a seismic damping device according to one embodiment of the present invention, showing the response story deformation. 10 is an analysis result of a response deformation comparison (Lv2 x 1.5 times) using a vibration damping device according to one embodiment of the present invention, showing the response acceleration. 10 is an analysis result of a response deformation comparison (Lv2 x 1.0 times) using a seismic damping device according to one embodiment of the present invention, showing the response story deformation. 10 is an analysis result of a response deformation comparison (Lv2 x 1.0 times) using a vibration damping device according to one embodiment of the present invention, showing the response acceleration. 16 is a diagram showing the load-deformation relationship (Lv x 2.0) for 16 steel dampers (16 oil buffer jacks). 10 is a diagram showing the load-deformation relationship (Lv x 2.0) for eight vibration control devices (32 oil buffer jacks and eight oil dampers).

A vibration damping device according to one embodiment of the present invention will be described with reference to the drawings.
As shown in Figure 1, the vibration control device 1 according to this embodiment is installed in, for example, the seismic isolation layer 12 of the upper and lower structures of the lower floor of a building. In the seismic isolation layer 12, a seismic isolation rubber 11 is installed between an upper joint 18a provided on an upper structure 18 and a lower joint 19a provided on a lower structure 19.

The vibration control device 1 is installed between a post 16a that is supported by the girder 16 of the lower structure 19 and extends upward, and a post 17a that is supported by the girder 17 of the upper structure and extends downward. The direction in which the girders 16, 17 extend is the X direction. The horizontal direction perpendicular to the X direction is the Y direction.

The vibration control device 1 comprises an oil damper 2 and a steel damper device 1X. In this embodiment, a total of four steel damper devices 1X are provided for each oil damper 2, with two spaced apart in the vertical and Y directions. The steel damper device 1X comprises a tie rod (tension member) 3, a pivot fixing portion 4, a stopper member (stopper mechanism) 5, a trunnion member (displacement tracking member) 6, and a center hole jack (jack) 7. There is no limit to the number of steel damper devices 1X, as long as two, six, or more steel damper devices 1X are arranged symmetrically with respect to the oil damper 2.

As shown in Figure 2, the extension direction (axial direction) of the oil damper 2 faces the X direction. The oil damper 2 is positioned between the posts 16a and 17a.

A connecting plate 16b is attached to the column 16a. One end 21 of the oil damper 2 is attached to a damper connecting portion 16c provided on the connecting plate 16b. The end 21 of the oil damper 2 is attached to the damper connecting portion 16c so that it can rotate around its axis, with the axis extending vertically relative to the damper connecting portion 16c.

A connecting plate 17b is attached to the post 17a. The other end 22 of the oil damper 2 is attached to a damper connecting portion 17c provided on the connecting plate 17b. The end 22 of the oil damper 2 is attached to the damper connecting portion 17c so that it can rotate around its axis, with the vertical direction being the axial direction.

The tie rod 3 is a steel damper. The tie rod 3 is inserted inside the center hole jack 7, which will be described later. The tie rod 3 is arranged in parallel with the oil damper 2. The tie rod 3 has a rod-shaped shaft 30. The length of the shaft 30 is parallel to the extension and contraction direction (X direction) of the oil damper 2. To avoid eccentric bending and twisting of the posts 16a, 17a, the tie rods 3 are arranged in a balanced manner above and below the oil damper 2 or on both sides in the Y direction (left and right sides). In this embodiment, four tie rods 3 are arranged above and below the oil damper 2 and on both sides in the Y direction.

The end 31 of the tie rod 3 is connected via the pivot fixing portion 4 to the upper and lower tie rod joint portions 16d provided on the joint plate 16b so that it can rotate around the axial direction, with the vertical direction being the axial direction.

A stopper member 5 is provided at the other end 32 of the tie rod 3. As shown in FIG. 3, the stopper member 5 has an outer nut 51A, an inner nut 51B, a rubber ring 52, a ring washer 53, and a disc spring 54. The inner nut 51B, rubber ring 52, ring washer 53, disc spring 54, and outer nut 51A are arranged in this order from the center of the axial direction X of the tie rod 3 toward the end 32.

The rubber ring 52 has a disk-shaped base portion 521 and a rubber ring main body portion 522. The male thread 34 of the tie rod 3 is inserted into an attachment hole formed in the center of the base portion 521.

The rubber ring main body 522 is formed from a rubber member that is elastically deformable in the axial direction X of the tie rod 3. The rubber ring main body 522 is formed in a disk shape with a thickness greater than that of the inner nut 51B. The inner nut 51B, which is threaded onto the male thread 34 of the tie rod 3, is placed in an attachment hole formed in the center of the rubber ring 52.

In the normal state (initial setting position where no displacement occurs in the oil damper 2), there is an axial distance (gap) G between the rubber ring main body 522 and the jack cylinder 72 of the center hole jack 7 (described below). Distance G is a gap that allows displacement of the oil damper 2 in the tensile direction. Distance G is, for example, approximately 300 to 500 mm.

The ring washer 53 is disk-shaped. The male thread 34 of the tie rod 3 is inserted into an attachment hole formed in the center of the ring washer 53. The outer edge of the ring washer 53 is fastened to the base portion 521 of the rubber ring 52 by a bolt 526.

The outer nut 51A is fastened to the male thread 32 via a disc spring 54 between it and the ring washer 53. The disc spring 54 constantly applies axial force to the outer nut 51A, preventing loosening of the outer nut 51A due to co-rotation caused by micro-vibrations and the like, and also positions the outer nut 51A.

As shown in Figure 1, a pair of connecting plates 171 are fixed to the support column 17a, spaced apart in the vertical direction. The trunnion member 6 is attached to the connecting plate 171 so as to be rotatable around its axis, which is the vertical axis. A through-hole that penetrates in the X direction is formed inside the trunnion member 6. A center hole jack 7 is fitted into the through-hole of the trunnion member 6. The trunnion member 6 causes the tie rod 3 to follow displacements of the oil damper 2 in the X and Y directions via the center hole jack 7.

The center hole jack 7 is, for example, a hydraulic jack. The center hole jack 7 has a jack body 71 formed in a substantially cylindrical shape and a jack cylinder 72 extending in the X direction from the jack body 71. The jack body 71 and jack cylinder 72 have through holes formed in the X direction. The shaft 30 of the tie rod 3 is inserted through the through hole so as to be slidable in the X direction.

As shown in Figure 3, under normal conditions, the jack cylinder 72 of the center hole jack 7 is extended by a distance H. The distance H is approximately several hundred mm (e.g., 250 mm). The jack cylinder 72 is either held under pressure while extended by the distance H, or is stationary without being held under pressure while extended by the distance H.

As shown in Figure 4, when the seismic isolation layer 12 (see Figure 1) is secured during strong winds, the jack cylinder 72 of the center hole jack 7 is in contact with or slightly spaced from the stopper member 5, and is either held under pressure or stationary without being held under pressure.

As shown in Figure 5, in the seismic isolation device 1, during an earthquake (wind load) exceeding Lv2, the center hole jack 7 acts as an oil buffer (shock absorber) to absorb energy. During an even larger earthquake (wind load), the tie rod 3 acts to absorb energy. In other words, it is a seismic isolation fail-safe device that absorbs energy in two stages depending on displacement and suppresses deformation.

A case where a force is applied and the vibration damping device 1 is displaced in the X and Y directions will be described.
As shown in Figure 6, when the post 16a and post 17a are displaced so that they approach each other, compressive forces act on the vibration control device 1 in the X and Y directions. The oil damper 2 contracts, shortening its overall length. The end 21 of the oil damper 2 rotates about its axis relative to the damper joint 16c. The end 22 of the oil damper 2 rotates about its axis relative to the damper joint 17c. The end 31 of the tie rod 3 rotates about its axis relative to the tie rod joint 16d. The trunnion member 6 rotates about its axis relative to the joint plate 171. As a result, the oil damper 1 as a whole tilts in the X direction. As a result, the jack body 71 and jack cylinder 72 slide around the shaft 30 of the tie rod 3, and the center hole jack 7 and trunnion member 6 are displaced in a direction approaching the pivot fixing part 4.

As shown in Figure 7, when post 16a and post 17a are displaced apart, tensile forces act on the vibration control device 1 in the X and Y directions. The oil damper 2 expands, increasing its overall length. The jack body 71 and jack cylinder 72 slide around the shaft 30 of the tie rod 3, causing the center hole jack 7 and trunnion member 6 to move away from the pivoting fixed portion 4 and toward the stopper member 5. When the tensile force increases further (the oil damper 2 displaces a predetermined amount in the tensile direction), the jack cylinder 72 of the center hole jack 7 abuts against the rubber ring body 522 of the stopper member 5. The jack cylinder 72 is compressed, and the extension length H of the jack cylinder 72 disappears. The center hole jack 7 functions as an oil buffer to absorb energy.

As shown in Figures 9 and 11, if a relief valve 73 is used in the center hole jack 7, when the jack cylinder 72 is compressed, the relief valve 73 attached to the hose (pipe) h1 connected to the pressurized port 78 of the cylinder tube 70 is activated. The oil O inside the cylinder tube 70 is discharged, providing viscous damping resistance and absorbing energy. As shown in Figure 9, the discharged oil O is stored in the tank 76 via the hose (pipe) h2. Alternatively, the oil O may be temporarily stored in a pump or accumulator via a hose (pipe) not shown. Furthermore, by discharging the oil O, excessive pressure inside the jack is prevented, preventing damage to the center hole jack 7.

As shown in Figure 10, if an orifice 74 is used in the center hole jack 7, when the jack cylinder 72 is compressed, the orifice 74 provided in the hose h1 operates. The oil O inside the cylinder tube 70 is discharged, exerting viscous damping resistance and absorbing energy.

As shown in Figure 7, when the tensile force increases further (the oil damper 2 is displaced by more than a predetermined amount in the tensile direction), the rubber ring main body 522 is compressed and deformed, eliminating the distance (gap) G and functioning as a stopper that suppresses the displacement of the trunnion member 6. The tie rod 3 acts to absorb the energy.

When the relief valve 73 shown in Figures 9 and 11 is used, there is no need to close the relief valve 73 unless the jack-up load exceeds the relief load provided by the relief valve 73 (500 kN in the example shown in Figure 5).

When the orifice 74 shown in Figure 10 is used, the valve or solenoid valve 75 on the hose h3 connected to the orifice 74 is closed during jacking up.

When a tank 76 is provided as shown in Figure 9, the oil O stored in the tank 76 is returned to the interior of the cylinder tube 70 through a pressure port 78 by a pump 77.

As shown in Figures 10 and 11, when there is no tank 76, the discharged oil O is returned to the inside of the cylinder tube 70 through the return port 79 by the hose h3.

As shown in Figure 7, to restore residual deformation, the center hole jack 7 is jacked up and functions as a jack, pulling the tie rod 3 and returning the seismic isolation layer to its original position. The center hole jack 7 may be operated by a manual pump or an electric pump and configured to automatically return to its original position using a control system.

Next, the effect of installing the seismic control device 1 described above was confirmed using a time history response analysis for an analytical model of a building with a seismic isolation layer.

The natural period of the model building is approximately 1.5 seconds when fixed. The seismic isolation period is approximately 5.0 seconds at 200% strain, and the building is made up of natural rubber bearings, lead plug bearings, and eight oil dampers (per direction). Four tie rods 3 (gapped steel dampers for seismic isolation equipped with an oil buffer jack) are installed per oil damper, for a total of 32 (per direction). Here, since this device (seismic control device 1) only acts in tension, only 16 of them actually bear the load. The gap amount is 400 mm, and the jack compression stroke is 150 mm.

In the diagrams below, "with gap steel damper" refers to the seismic control device 1 described above, while "without gap steel damper" (a configuration equipped with oil damper 2, but without tie rod 3, pivot fixing portion 4, stopper member 5, trunnion member 6, and center hole jack 7) and "seismic isolation clearance (retaining wall collision)" are shown as comparative examples. As shown in Figure 12, a comparison of the presence and absence of this device (seismic control device 1) for an input of approximately 2.0 times the Kobe Level 2 specified in the Notification, shows that while the maximum deformation before installation was 692 mm, after installation it was reduced to less than 626 mm, confirming a 66 mm reduction in deformation. Meanwhile, as shown in Figure 13, the response acceleration increases after installation.

Furthermore, as shown in Figure 14, a comparison of the cases with and without this device shows that, in response to an input approximately 1.5 times the Kobe Level 2 (equivalent to Level 3), the maximum deformation was 425 mm before installation, but after installation, the deformation was reduced to 416 mm, demonstrating the energy absorption effect of the oil buffer, which acts from 400 mm. Furthermore, as shown in Figure 15, the response acceleration increases slightly, but remains below 250 gal, below the guideline for furniture tipping.

On the other hand, as shown in Figures 16 and 17, at 1.0x input at Level 2, the maximum deformation of the seismic isolation layer is 231 mm, within a gap of 400 mm, so the device does not come into effect, and the response acceleration is sufficiently reduced to 150 gal or less without impairing the seismic isolation performance.

Figure 19 also shows the history (represented as a pair of left and right) obtained from the response analysis of this device when the gap displacement is 550 mm.

In a seismic control device 1 configured in this way, when the tensile force increases, the jack cylinder 72 of the center hole jack 7 comes into contact with the stopper member 5 and is compressed. The extended length of the jack cylinder 72 disappears, and the center hole jack 7 functions as an oil buffer to absorb energy. When the tensile force increases further and the jack cylinder 72 is further compressed, the tie rod 3 comes into action to absorb energy. As a result, more energy can be absorbed before the limit deformation is reached. The number of seismic control devices 1 required can be reduced compared to before.

In addition, during an earthquake, when the jack cylinder 72 of the center hole jack 7 is compressed, either the relief valve or the orifice acts, discharging the oil inside the center hole jack 7 and exerting viscous damping resistance to absorb energy.

Furthermore, after an earthquake, residual deformation can be restored by closing the valve on the pipeline leading to either the relief valve or the orifice, or by jacking up the structure to a level below the relief load.

Furthermore, the tie rod 3 does not become plastic until the extension length H of the jack cylinder 72 disappears. Therefore, in the event of an earthquake (wind load) that does not affect the tie rod 3, there is no need to replace the tie rod 3.

Four steel damper devices 1X can be installed in parallel with the oil damper 2, streamlining the installation space. The oil damper 2 and the four steel damper devices 1X may also be installed in separate locations.

The number of oil dampers 2 required for an earthquake equivalent to level 3 can be reduced by absorbing energy using the oil buffer, which also serves as the center hole jack 7.

In strong winds, the seismic isolation layer 12 can be fixed by extending the jack cylinder 72 of the center hole jack 7 in advance until it abuts the stopper member 5, preventing elevators passing through the seismic isolation layer 12 from being stopped due to deformation caused by wind load.

It exerts two levels of damping force according to the external force level, allowing for multi-stage damping performance and simultaneously satisfying three requirements: ensuring habitability in small to medium earthquakes, preserving belongings in large earthquakes, and ensuring safety in unexpectedly large earthquakes.

Note that the shapes and combinations of the components shown in the above-described embodiment are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

1. Seismic control device 1X Steel damper device 2. Seismic control damper 3. Tie rod (tensile material)
5 Stopper member (stopper mechanism)
6 Trunnion member 7 Center hole jack (jack)
12 seismic isolation layer 18 upper structure 19 lower structure
72 Jack cylinder

Claims (3)

A seismic control device installed in a seismic isolation layer between building structures,
tension members connected between the building structures;
a stopper mechanism provided on the tension member;
a jack through which the tension member is passed;
a displacement-following member that is attached to the jack and is attached to the building structure so as to be rotatable around an axis in the vertical direction, and causes the tension member to follow the displacement of the seismic isolation layer;
Normally, the jack is in a state where the cylinder is extended,
In the event of an earthquake, the cylinder abuts against the stopper mechanism, causing the cylinder to compress. The seismic damping device of claim 1, wherein when the cylinder of the jack is compressed during an earthquake, either the relief valve or the orifice acts. The seismic damping device described in claim 2 is configured to close the valve in the pipe leading to either the relief valve or the orifice after an earthquake.