JPH0369431B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention utilizes an earthquake observation network and a communication network during an earthquake to apply an excitation force in the opposite direction to a building to cancel input seismic motion according to commands from a control device. , relates to a vibration damping method for buildings that prevents damage caused by resonance phenomena, etc.

[Conventional technology]

Conventionally, in seismic design of high-rise buildings and important structures, dynamic design has been performed to check safety by calculating the ground movement and building response during an earthquake.

Earthquake resistance methods include seismic isolation or attenuation construction methods in which laminated rubber bearings or dampers are interposed between the building and the foundation, methods that consume earthquake energy by destroying non-main building components, walls or columns. There is a method to adjust the rigidity of the building to the optimum level by creating slits in the building.

In addition, the applicant previously proposed in Japanese Patent Application No. 60-205041 (Japanese Unexamined Patent Publication No. 62-63776) that a seismic observation network and a communication network were used to interpose a structure between a building and its ground-side foundation. The application is for a seismic isolation system that controls a connected or releasable trigger device.

[Problem that the invention seeks to solve]

By the way, confirmation of the safety of buildings designed using current seismic design methods in the event of an earthquake is based on the basic idea that the energy absorbed by the hysteresis characteristics associated with plasticization of the structure exceeds the seismic energy acting on the structure. However, this has the problem of reliability regarding the history loop characteristics.

Furthermore, with the exception of the above-mentioned application, all conventional methods provide a passive seismic structure against natural external forces such as earthquakes and wind, and because the building has a specific natural frequency, it cannot withstand the uncertain input of an earthquake. On the other hand, resonance phenomena cannot be avoided.

Rather than using the passive seismic resistance method described above, this invention applies an excitation force in the opposite direction to the building based on the judgment of the response prediction system based on the detected seismic motion, and suppresses resonance in the building and inside the building. The aim is to ensure the safety of equipment, residents, etc.

[Means for solving problems]

In the vibration control method of this invention, a vibration excitation device consisting of an additional mass and a drive mechanism that vibrates at a desired frequency according to commands from a control device is installed on the top of a building or inside the building, and the vibration control method of the building is carried out as follows. Do this.

The occurrence of an earthquake is detected by earthquake sensing devices placed in both narrow and wide areas around buildings, and the observation data is transmitted to the control device via wired and wireless communication networks. Wide-area earthquake sensing equipment connects seismometers at existing earthquake observation points or specially installed equipment using micro-wires or telephone lines. In addition, narrow-area earthquake sensing equipment consists of seismometers installed around buildings or in the ground around them, and vibration centers installed at the base of buildings or inside buildings, and the effects of wind force etc. are detected by vibration sensors inside buildings.

Regarding the detected earthquake, the computer in the control device determines the scale of the earthquake, analyzes the frequency characteristics, predicts the amount of response, etc., and determines whether or not the vibration of the building should be controlled, and if so, the amount of control. Calculate the frequency and direction in which the excitation force applied to the building by the vibration device cancels the input seismic motion and the response of the building is minimized.

It transmits commands from the control device to the vibration device and applies vibration force to the building in accordance with the input seismic motion. This excitation force is sufficient as long as it suppresses the resonance of the building; for example, it applies equal and opposite forces at the natural frequency where resonance occurs.

The vibration device is one in which an additional mass block supported by a roller support and connected to a part of the building frame via an elastic member such as a spring is vibrated by an actuator controlled by a control device. etc. are possible.

Note that this invention does not preclude its use in combination with conventional seismic isolation construction methods and seismic attenuation construction methods, and by using them in combination, safety and economic efficiency can be increased.

〔Example〕

Next, the illustrated embodiment will be explained.

Figure 1 shows the outline of this invention, and Figure 2 shows the outline of this invention.
To explain this along with the block diagram in the figure, first, 3 seismometers near the epicenter
a, seismometer 3b near buildings centered on building 1;
Furthermore, the control device 2 (usually the building 1
(a computer installed inside). If the control device 2 determines that the magnitude of the earthquake exceeds a certain tolerance based on the vibration acceleration of the earthquake, it measures the acceleration and analyzes the frequency characteristics, and determines the vibration characteristics of the building.
Predictive calculations of displacement, etc. are performed, and if these exceed a certain tolerance value, the control device 2 sends a command to the vibration device 5, and the vibration device 5 causes the building 1 to move to the predicted resonance point of the building 1. It is possible to apply vibration in the opposite direction to the earthquake input in accordance with the natural frequency of the earthquake, thereby canceling out the resonant component.

To give a numerical example, for seismometers 3a distributed over a wide area, if the epicenter X, seismometer 3a, and target building 1 are in a straight line and there is a distance of 50 km between them, from P wave detection to S wave operation Approximately 18.5 seconds, S
It takes approximately 12 seconds from wave detection to S-wave operation, and control only needs to be completed during this time. Also, the distance from the epicenter X for the narrow-area seismometer 3b is
In the case of 100 km, there is a time of about 12 seconds from P wave detection to S wave operation, and it is sufficient to issue control commands during this time.

Also, the actual response is from the earthquake sensor 4 inside the building 1.
It is sensed and feedback is provided to make corrections.

FIGS. 3 and 4 show an example of the vibration device 5 installed on the roof of the building 1. FIG.

In other words, the additional mass block 7, which is slidably supported by a roller bearing 8, can be vibrated by a plurality of actuators 6 fixed to the building 1, and the additional mass block 7 can be vibrated by a plurality of actuators 6 fixed to the building 1. connected via a spring 9 to maintain the
By operating the actuator, vibrations are applied to the building from the rising portion 1'. In addition, 1 in the figure
0 is a hydraulic pump, 11 is a servo valve, and 12 is a stopper to prevent the displacement from becoming too large.

〔Effect of the invention〕

The controller's computer instantaneously judges data sensed by earthquake sensing devices placed in both narrow and wide areas, and based on the predicted response, applies vibrations to the building in the opposite direction to the seismic force, thereby canceling out resonance components. This makes it possible to ensure the safety of the building, its equipment, and its occupants in accordance with the characteristics of each earthquake, and to allow work to be carried out peacefully within the building.

Existing facilities can be used for earthquake observation networks and communication networks.
Furthermore, facility costs can be reduced by sharing the facility with multiple buildings.

Furthermore, since the seismic observation network, computer-based control device, vibration excitation device, etc. can be added later, it can also be applied to existing buildings.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an outline of the invention, FIG. 2 is a block diagram, FIG. 3 is a front view showing an example of the vibration device, and FIG. 4 is a plan view. 1...Building, 2...Control device, 3a, 3b...
Seismometer, 4... Vibration sensor, 5... Vibration device,
6...actuator, 7...additional mass block, 8...roller bearing, 9...spring, 10...
Hydraulic pump, 11...servo valve, 12...stopper.

Claims (1)

[Scope of Claims] 1. A vibrating device consisting of an additional mass and a drive mechanism that operates at an arbitrary frequency according to a command from a control device is provided at the top of a building, and the vibrating device is installed at the top of a building, inside the building, and in a narrow area. Earthquakes are sensed by earthquake sensing devices placed over a wide area, observation data from the earthquake sensing devices is input to the control device, the earthquake is analyzed by the control device, and based on the obtained seismic response prediction, the A method for damping vibrations of a building, comprising activating a vibration excitation device to apply an excitation force in the opposite direction to the building to cancel input seismic motion. 2. The vibration excitation device is supported by a roller support, and has an additional mass block connected to a part of the building frame via a plurality of elastic members, which is fixed to the building and controlled by the control device. 2. The method of damping vibrations of a building according to claim 1, wherein vibration is caused by a plurality of actuators.