JP7776355B2 - Wind-resistant locking mechanism for seismic isolation structures - Google Patents

Description

The present invention relates to a wind-resistant locking mechanism for seismic isolation structures.

The amount of damper to be inserted into the seismic isolation layer of a seismically isolated building is determined by the greater of either the optimal amount for earthquakes or the amount required for wind. In recent years, as buildings have become larger, the amount of damper required for wind has tended to increase, resulting in excessive damping for earthquakes and in some cases preventing optimal seismic isolation performance.

Japanese Patent Application Laid-Open No. 2004-263430

Known conventional wind-resistant locking mechanisms include passive and electrically controlled types.
For example, a passive mechanism is the wind-resistant shear pin mechanism. In this mechanism, a shear pin is rigidly inserted directly between the upper and lower seismic isolation structures. However, in order to ensure seismic isolation during earthquakes and to prevent the shear pin from frequently breaking due to relatively small earthquakes, this configuration requires the shear pin to be removed at all times and manually inserted only when a strong wind is expected. Furthermore, if an earthquake occurs simultaneously with a strong wind, the shear pin will be subjected to excessive shear force and break, requiring its removal and replacement.

Another example is one in which shear pins are inserted between the upper and lower structures via elastic beams. The elastic beams act as buffers, preventing the shear pins from frequently breaking off due to relatively small earthquakes, making it possible to leave the shear pins inserted at all times. However, with this configuration, the characteristics of the seismic isolation layer during an earthquake depend on the elastic beams, and the original seismic isolation performance cannot be achieved until the shear pins break off due to excessive shear force.

A known electrically controlled locking mechanism is one that uses oil dampers. Specifically, this mechanism adds a locking mechanism to a general-purpose oil damper, and uses earthquake and wind sensors to detect earthquakes and wind, locking the oil damper during strong winds other than earthquakes. However, because this mechanism is based on an oil damper, it is only effective in the damper axial direction (one direction), and devices must be inserted in both the X and Y directions. Additionally, it is necessary to place the necessary number of oil dampers as a wind-resistant locking mechanism, and because these dampers act as normal oil dampers during an earthquake, in some cases the damper volume may be excessive for an earthquake.

For these reasons, there is a need for a wind-resistant locking mechanism for seismic isolation structures that can demonstrate their inherent seismic isolation performance in both earthquakes and storms.

The present invention was made in consideration of the above-mentioned problems, and aims to provide a wind-resistant locking mechanism for a seismic isolation structure that can demonstrate seismic isolation performance in both earthquakes and storms.

To achieve the above objective, the wind-resistant locking mechanism for a seismic isolation structure of the present invention comprises a wind speed sensor and an earthquake sensor installed in the seismic isolation structure, a pump that operates in response to the detection results of the wind speed sensor and the earthquake sensor, a hydraulic jack device connected to the pump and installed in the seismic isolation layer between the upper structure and the lower structure, and a control unit that controls the pump. The hydraulic jack device has a piston housing fixed to the lower structure, a piston that moves up and down by hydraulic pressure supplied from the pump, and a pod section arranged above the piston, and is equipped with a restraining member that restrains the relative horizontal displacement between the piston housing and the pod section. The control unit is characterized in that when the detection result of the wind speed sensor exceeds a set value, the control unit raises the piston to bring the pod section into contact with the underside of the upper structure, and when the detection result of the earthquake sensor exceeds the set value or during normal times when the detection results of the wind speed sensor and the earthquake sensor are below the set value, the control unit lowers the piston to separate the pod section from the underside of the upper structure.

According to this invention, the hydraulic pressure supplied to the hydraulic jack device is controlled by a pump. The control unit controls the hydraulic pressure based on the detection results of the wind speed sensor and earthquake sensor, eliminating the need for manual operation when wind-resistant locking. It can also be effective in all horizontal directions. The restraining member can limit the relative horizontal movement distance between the piston accommodating section and the pod section, and by restraining the displacement of the pod section relative to the lower structure, the wind-resistant locking mechanism can be kept functional. Furthermore, the hysteresis characteristics of the seismic isolation layer can be made completely independent between earthquakes and storms, allowing the desired seismic isolation performance to be achieved in both earthquakes and storms.

In the present invention, a sliding member may be provided between the upper surface of the piston and the lower surface of the pod portion.
According to this invention, the horizontal force (shear force) acting on the piston can be controlled, and damage to the piston can be prevented.

In the present invention, a damping material may be provided on an upper surface of the pod portion, and a damping plate may be provided on a lower surface of the upper structure.
According to this invention, the seismic isolation layer can function without any problems even if residual displacement occurs in the seismic isolation layer due to an earthquake or a windstorm, and restoration operations after a major earthquake can be eliminated.

In the present invention, one pump may be connected to a plurality of hydraulic jack devices.
According to this invention, the number of pumps to be installed can be reduced, and the arrangement of seismic isolation layers can be made more efficient.

In addition, the present invention may be configured such that the restraint member is composed of a downward-facing wall extending downward from the periphery of the pod portion, and when the pod portion is in contact with the underside of the upper structure, the downward-facing wall encloses the piston accommodating portion in a state where it at least partially overlaps with the piston accommodating portion in the vertical direction.
According to this invention, simply by providing a descending wall in the pod section as a restraining member, the relative horizontal movement distance between the piston accommodating section and the pod section can be limited, and by restraining the displacement of the pod section relative to the lower structure, the wind-resistant locking mechanism can be kept functional.

The present invention provides a wind-resistant locking mechanism for a seismic isolation structure that can demonstrate seismic isolation performance in both earthquakes and storms.

1 is a schematic diagram of a seismic isolation structure according to an embodiment of the present invention; 1 is a schematic structural diagram of a wind-resistant locking mechanism according to an embodiment of the present invention; FIG. 2 is a front view showing the hydraulic jack device of the present embodiment in a jacked-down state. FIG. 2 is a front view showing the hydraulic jack device of the present embodiment in a jacked-up state. 3 is a control flowchart of the hydraulic jack device of the present embodiment.

The wind-resistant locking mechanism for a seismic isolation structure according to an embodiment of the present invention will be described below with reference to Figures 1 to 5.

As shown in FIG. 1, the seismic isolation structure 1 of this embodiment has a seismic isolation layer 4 between the upper structure 2 and the lower structure 3. The seismic isolation layer 4 is provided with a seismic isolation device 5 such as seismic isolation rubber, and a hydraulic jack device 11 of a wind-resistant locking mechanism 10. In addition, a wind speed sensor 12 is provided on the roof of the upper structure 2, and an earthquake sensor 13 is provided on the lowest layer of the lower structure 3. Note that the wind speed sensor 12 and earthquake sensor 13 may be installed in locations other than those described above.

As shown in Figure 2, the wind-resistant locking mechanism 10 includes a hydraulic jack device 11, a wind speed sensor 12, an earthquake sensor 13, a pump 14 that drives the hydraulic jack device 11, a control unit 15 that controls the operation of the pump 14, and a hose 16 that connects the pump 14 and the hydraulic jack device 11.

As shown in Figures 3 and 4, the hydraulic jack device 11 has a piston housing 21 fixed to the lower structure 3, a piston 22 that moves up and down relative to the piston housing 21 by hydraulic pressure supplied below the piston from the pump 14, and a pod section 23 disposed above the piston 22.

The piston accommodating section 21 includes a flange-shaped bottom section 31 fixed to the lower structure 3, a side wall section 32 extending cylindrically from the bottom section 31, and an upper flange section 33 extending from the upper end of the side wall section 32 toward the central axis O1. For example, the piston accommodating section 21 is formed in a cylindrical shape.

The piston 22 is housed in the piston housing 21. The piston 22 has a columnar main body 35 and a flange 36 formed at the lower end of the main body 35. For example, the piston 22 is formed in a cylindrical shape. A sliding member 40 is attached to the upper surface 35a of the main body 35. The sliding member 40 is, for example, a friction plate or a stainless steel plate. The piston 22 moves up and down hydraulically. When jacked down, the piston 22 is housed in the hollow portion 34 of the piston housing 21. When jacked up, the main body 35 of the piston 22 protrudes upward from an opening 33a formed inside the upper flange 33 of the piston housing 21. The piston 22 can rise to a position where the flange 36 abuts the upper flange 33 of the piston housing 21.

The pod section 23 is disposed above the piston 22 and moves in accordance with the up and down movement of the piston 22. When jacked down, the pod section 23 has a cylindrical shape with a bottom that covers the piston accommodating section 21 from above. The pod section 23 comprises a plate-shaped main body 41 located above the piston 22 and a descending wall 42 extending downward from the periphery of the main body 41. When jacked up, the descending wall 42 is sized so that at least a portion of its lower part overlaps the piston accommodating section 21 in the vertical direction. A damping material 43 is attached to the upper surface 41a of the main body 41 of the pod section 23. The damping material 43 is, for example, a friction plate or a stainless steel plate.

Brake plates 45 are attached to the underside 2a of the upper structure 2. When jacked up, the brake material 43 of the pod section 23 and the brake plates 45 of the upper structure 2 come into contact and are configured to slide. The brake plates 45 are made of, for example, stainless steel.

Sliding resistance can be exerted when the braking material 43 and braking plate 45 are in contact. For example, if the vertical force of the hydraulic jack of the hydraulic jack device 11 is 4000 kN and the friction coefficient between the braking material 43 and braking plate 45 is 0.3, a single hydraulic jack device can exert a horizontal resistance capacity of 1200 kN. By installing multiple such hydraulic jack devices 11, it becomes possible to cope with wind loads in ultra-high-rise seismic isolation buildings.

In the wind-resistant locking mechanism 10, one hydraulic jack unit 11 is connected to one pump 14. Note that multiple hydraulic jack units 11 may be connected to one pump 14. When connecting multiple hydraulic jack units 11, a pump 14 with a discharge volume that can accommodate multiple hydraulic jack units 11 should be selected. The number and placement of pumps 14 should be determined so that the hoses 16 are of an appropriate length, taking into consideration the plan for the layout of the hydraulic jack units 11 in the seismic isolation layer 4.

When the wind-resistant locking mechanism 10 functions, it is in the state shown in Figure 4, with the piston 22 of the hydraulic jack device 11 in the raised position, exerting horizontal frictional resistance. To control the horizontal force acting on the piston 22, a sliding member 40 with a low coefficient of friction is disposed between the upper surface 35a of the main body 35 of the piston 22 and the lower surface 41b of the main body 41 of the pod portion 23. In this embodiment, the sliding member 40 is attached to the upper surface 35a of the main body 35 of the piston 22, but it may also be attached to the lower surface 41b of the main body 41 of the pod portion 23.

When a horizontal force acts on the pod section 23 through the friction surface with the upper structure 2, only the friction resistance of the sliding member 40 is transmitted to the piston 22, and the remaining force is handled by the bearing resistance of the inner surface 42a of the descending wall 42 of the pod section 23 and the side surface 25 of the piston accommodating section 21, preventing direct action on the piston 22. For example, in the above case, if a sliding member 40 with a friction coefficient of 0.1 is used, the horizontal force transmitted to the piston 22 is 400 kN, and the remaining 800 kN (= 1200 - 400) kN of the 1200 kN horizontal force is handled by the bearing resistance. As a result, excessive horizontal shear force is not generated in the piston 22, preventing damage to the hydraulic jack device 11.

Next, the control law will be explained using the flowchart of FIG.
In step S1, wind speed information from the wind speed sensor 12 attached to the seismic isolation structure 1 and acceleration information from the earthquake sensor (acceleration sensor) 13 are measured, and the measurement values are collected in the control unit 15. Basically, the hydraulic jack device 11 of the wind-resistant locking mechanism 10 is jacked down normally and during earthquakes, and is jacked up to enter a wind-resistant lock state when an external wind force is applied, such as during a storm. The threshold values for jacking due to earthquakes or external wind forces can be freely set.

In step S2, the maximum wind speed detected by the wind speed sensor 12 is compared with a preset value (threshold value). If the maximum wind speed is greater than the set value, proceed to step S3; if it is equal to or less than the set value, proceed to step S6.

In step S3, it is determined that the wind blowing against the seismic isolation structure 1 is greater than the set value, so the wind-resistant locking mechanism 10 is turned ON. Specifically, a drive signal is sent from the control unit 15 to the pump 14, which drives the pump 14 and applies hydraulic pressure to the hydraulic jack device 11 via the hose 16. When hydraulic pressure is applied, the piston 22 rises due to the hydraulic pressure. The pod section 23 also rises as if pushed by the piston 22, and the braking material 43 attached to the upper surface 41a of the main body 41 of the pod section 23 abuts against the braking plate 45 attached to the lower surface 2a of the upper structure 2. This results in a wind-resistant lock state with frictional resistance at the abutting section (= friction coefficient × jack load).

In step S4, in the wind-resistant lock state, the acceleration of the earthquake sensor 13 is measured, and the measured value is detected by the control unit 15. The acceleration detected by the earthquake sensor 13 is compared with a preset value (threshold value). If the detected acceleration is greater than the set value, proceed to step S5; if it is equal to or less than the set value, proceed to step S7.

In step S5, it is determined that an earthquake of a magnitude greater than the preset magnitude has occurred in the wind-resistant lock state, and the wind-resistant lock state is quickly changed from ON to OFF. Specifically, the control unit 15 sends a signal to release a valve (not shown) in the pump, and the jack oil pressure decreases, causing the pod section 23 to separate from the underside 2a of the upper structure 2, and the piston 22 and pod section 23 to descend, returning to the jacked-down state. When the jack oil pressure decreases, the contact surface pressure between the pod section 23 and the upper structure 2 decreases, reducing the frictional resistance at the contact point and releasing the lock state.

In step S6, since it is determined that the wind blowing against the seismic isolation structure 1 is below the set value, the wind-resistant locking mechanism is turned OFF. However, if it is determined in step S2 that the maximum wind speed exceeds the set value, the wind-resistant locking mechanism remains ON for, for example, one hour after the determination. By configuring it in this way, it is possible to prevent the wind-resistant locking mechanism 10 from frequently cycling ON and OFF.

In step S7, it is determined that no earthquake greater than the set value has occurred in the wind-resistant lock state, and the wind-resistant lock state is maintained in the ON state. However, if it is determined in step S4 that a large earthquake has occurred, the wind-resistant lock mechanism is maintained in the OFF state for, for example, five minutes after the determination. By configuring it in this way, it is possible to prevent the wind-resistant lock mechanism 10 from frequently cycling ON/OFF, and the seismic isolation function of the seismic isolation layer 4 can be reliably maintained even if aftershocks or other earthquakes occur.

As mentioned above, a timer may be provided to maintain the jacking behavior that should occur when a disturbance is detected for a certain period of time from the moment an earthquake or wind force is detected. The one hour period in step S6 and the five minutes period in step S7 are examples, and these periods can be changed as appropriate.

Furthermore, to ensure that the jacking-down operation is completed reliably, a timer may be added to keep the hydraulic pressure release valve open for a certain period of time. Alternatively, a vertical limit switch or vertical displacement meter may be added to the hydraulic jack device 11, and a sensor may be provided to physically detect when the piston 22 has been lowered by more than a certain displacement.

Furthermore, in a seismic isolation structure 1 equipped with a seismic isolation layer on an intermediate floor, such as seismic isolation layer 4, a control rule may be added to observe the displacement of seismic isolation layer 4, which is the stopping condition, and jack up the elevator if the observed value exceeds a certain value, so that elevators passing through the seismic isolation layer 4 do not stop during strong winds such as those during seasonal winds. The displacement of the seismic isolation layer 4 can be measured using a horizontal limit switch or horizontal displacement meter. However, to ensure that the observed displacement is due to wind forces rather than to minute vibrations such as earthquakes or construction vibrations, or residual displacement, it is desirable to combine multiple conditions to activate the wind-resistant lock. For example, the wind-resistant lock may be activated when all of the following conditions are met: wind speed of 20 m/s or more, acceleration of 5 gal or less, and seismic isolation layer displacement of 1 cm or more.

In addition, if the external wind force increases further while the seismic isolation layer 4 remains in the wind-resistant locked state, there is a risk that the wind-resistant lock friction force will be exceeded and the hydraulic jack unit 11 will slide. In such a case, the hydraulic jack unit 11 can be allowed to slide and function as a friction damper. Alternatively, based on the design concept of the hydraulic jack unit 11 targeting external wind forces within a specific return period range and performing wind-resistant locking to ensure habitability and continue elevator operation, the hydraulic jack unit 11 can be jacked down in response to external forces exceeding this range, releasing the wind-resistant lock. In this case, the displacement of the seismic isolation layer 4 can be measured using a horizontal limit switch or horizontal displacement meter, and the jack can be jacked down when the value exceeds a certain threshold.

According to this embodiment, the base-isolated structure 1 includes a wind speed sensor 12 and an earthquake sensor 13, a pump 14 that is driven in response to the detection results of the wind speed sensor 12 and the earthquake sensor 13, a hydraulic jack device 11 that is connected to the pump 14 and is provided in the base-isolated layer 4 between the upper structure 2 and the lower structure 3, and a control unit 15 that controls the pump 14. The hydraulic jack device 11 includes a piston housing 21 fixed to the lower structure 3, a piston 22 that moves up and down by hydraulic pressure supplied from the pump 14, and a pod section 15 that is disposed above the piston 22. 23, and a falling wall (restraint member) 42 is provided that restrains the relative horizontal displacement between the piston accommodating section 21 and the pod section 23. The control section 15 is configured to raise the piston 22 and bring the pod section 23 into contact with the underside 2a of the upper structure 2 when the detection result of the wind speed sensor 12 is equal to or greater than a set value, and to lower the piston 22 and separate the pod section 23 from the underside 2a of the upper structure 2 when the detection result of the earthquake sensor 13 is equal to or greater than the set value, or during normal times when the detection results of the wind speed sensor 12 and earthquake sensor 13 are less than the set value.

With this configuration, the hydraulic pressure supplied to the hydraulic jack device 11 can be controlled by the pump 14 in response to a drive signal from the control unit 15. The control unit 15 can then control the drive of the pump 14 and adjust the hydraulic pressure based on the detection results of the wind speed sensor 12 and earthquake sensor 13, eliminating the need for manual operation when wind-resistant locking. Furthermore, because the piston 22 only moves up and down, it can be effective in all horizontal directions. The wind-resistant lock state can be achieved by raising the piston 22 and abutting the pod section 23 against the upper structure 2. The falling wall (restraint member) 42 limits the horizontal relative movement distance between the piston accommodating section 21 and the pod section 23, thereby restraining the displacement of the pod section 23 relative to the lower structure 3, thereby maintaining the wind-resistant locking mechanism in a functional state. In other words, the seismic isolation hysteresis characteristics can be completely independent between earthquakes and storms, allowing the desired seismic isolation performance to be achieved in both earthquakes and storms.

In addition, by providing a sliding member 40 between the upper surface 22a of the piston 22 and the lower surface 41b of the main body 41 of the pod section 23, the horizontal force (shear force) acting on the piston 22 can be controlled, preventing damage to the piston.

In addition, a damping material 43 is provided on the upper surface 41a of the main body 41 of the pod section 23, and a damping plate 45 is provided on the underside 2a of the upper structure 2. This allows the seismic isolation layer to function without any problems even if residual displacement occurs in the seismic isolation layer due to an earthquake or strong wind, and also eliminates the need for restoration operations after a major earthquake.

Furthermore, the restraint member is composed of a falling wall 42 extending downward from the periphery of the pod section 23, and is configured to enclose the pod section 23 with the falling wall 42 overlapping at least partially in the height direction with the piston accommodating section 21 when the pod section 23 is in contact with the underside 2a of the upper structure 2. In other words, with the simple configuration of providing the falling wall 42, the relative horizontal movement distance between the piston accommodating section 21 and the pod section 23 can be limited, and the wind-resistant locking mechanism 10 can be kept functional. Furthermore, when a horizontal force acts on the pod section 23 through the friction surface with the upper structure 2, only the friction resistance portion of the sliding member 40 is transmitted to the piston 22, and the remaining portion is handled by the bearing pressure resistance of the inner surface 42a of the falling wall 42 of the pod section 23 and the side surface 25 of the piston accommodating section 21, preventing direct action on the piston 22.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments. The present invention can be modified within the scope of the gist of the invention as set forth in the claims.

In addition, in this embodiment, a sliding member 40 is provided between the upper surface 22a of the piston 22 and the lower surface 41b of the main body portion 41 of the pod portion 23, but the sliding member 40 may be omitted as long as the desired frictional resistance is ensured.

In addition, in this embodiment, a braking material 43 is provided on the upper surface 41a of the main body 41 of the pod section 23, and a braking plate 45 is provided on the lower surface 2a of the upper structure 2, but the braking material 43 and braking plate 45 do not have to be provided as long as the desired frictional resistance is ensured.

Furthermore, in this embodiment, the falling wall 42 of the pod section 23 functions as a restraint member, but the restraint member may have a different configuration.

1 Seismic isolation structure 2 Upper structure 2a Lower surface 3 Lower structure 4 Seismic isolation layer 10 Wind-resistant locking mechanism 11 Hydraulic jack device 12 Wind speed sensor 13 Earthquake sensor 14 Pump 15 Control unit 21 Piston accommodating section 22 Piston 22a Upper surface 23 Pod section 40 Slider 41 Main body section 41a Upper surface 41b Lower surface 42 Downward wall (restraint member)
43 Braking material 45 Braking plate

Claims (5)

a wind speed sensor and an earthquake sensor provided in the seismic isolation structure;
a pump that is driven in response to the detection results of the wind speed sensor and the earthquake sensor;
a hydraulic jack device connected to the pump and installed in the seismic isolation layer between the upper structure and the lower structure;
a control unit that controls the pump,
The hydraulic jack device is
a piston accommodating portion fixed to the lower structure;
a piston that moves up and down by hydraulic pressure supplied from the pump;
a pod portion disposed above the piston,
a restraining member is provided that restrains horizontal relative displacement between the piston accommodating portion and the pod portion,
The control unit
When the detection result of the wind speed sensor becomes equal to or greater than a set value, the piston is raised to bring the pod part into contact with the lower surface of the upper structure,
A wind-resistant locking mechanism for a seismic isolation structure, characterized in that when the detection result of the earthquake sensor exceeds a set value, and when the detection results of the wind speed sensor and the earthquake sensor are below a set value under normal circumstances, the piston is lowered to separate the pod portion from the underside of the upper structure. The wind-resistant locking mechanism for a seismic isolation structure described in claim 1, wherein a sliding member is provided between the upper surface of the piston and the lower surface of the pod portion. A wind-resistant locking mechanism for a seismic isolation structure as described in claim 1 or claim 2, in which a damping material is provided on the upper surface of the pod section and a damping plate is provided on the underside of the upper structure. A wind-resistant locking mechanism for a seismic isolation structure according to any one of claims 1 to 3, wherein one pump is connected to multiple hydraulic jack devices. the restraint member is formed of a falling wall extending downward from the peripheral edge of the pod portion,
A wind-resistant locking mechanism for a seismic isolation structure as described in any one of claims 1 to 4, wherein the pod section is in contact with the underside of the upper structure and the falling wall is configured to enclose the piston accommodating section in a state where it overlaps at least partially in the height direction.