JPH0249875A - Damping method and device thereof - Google Patents

Abstract

PURPOSE:To make absolute damping come to fruition by detecting earthquake motion being inputted into a structure, and controlling an amount of expansion displacement in a power means in accordance with the detected value from which a long-periodic large amplitude constituent is eliminated. CONSTITUTION:Earthquake motion being inputted into a structure 4 at an earthquake is detected by a detecting means 7 set up at the side of the ground 2, and a detection signal is outputted to a filter 10 via an amplifier 8. Next, this detection signal inputted into the filter 10 is eliminated of a large amplitude constituent of its long-periodic ingredient phi which has a fear to cause a large deformation in a long period holding means 3 such as laminated rubber or the like by the filter 10. Then, the signal eliminated of the large amplitude constituent is outputted to a control means 9. In addition, this control means 9 controls an amount of expansion displacement in a power means 5 consisting of a hydraulic cylinder or the like on the basis of the inputted signal.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a method for damping a long-period structure using a damping force applied from a power means such as an actuator. The present invention relates to a vibration damping method and apparatus for detecting the response of a structure due to earthquake motion and input from the power means, and controlling the amount of expansion/contraction displacement of the power means based on the detected values.

(Prior Art) Various vibration damping methods have been devised for regulating the shaking of structures due to earthquake motions and the like. for example,
A power means such as an actuator that is driven to extend and contract in the direction of ground motion is installed between the structure supported on the ground via a long-period means such as an isolator made of laminated rubber, a sliding bearing member made of rollers, etc., and the ground. The power means generates a damping force in the opposite direction to the seismic motion, insulating the structure from the moving ground and maintaining the structure in a constant position as much as possible regardless of ground motion (absolute control). Vibration damping mechanisms are known (Collection of Academic Lectures at the Architectural Institute of Japan (Kinki) (October 1986), p. 9).
05-906 etc.)

The present applicant hereby proposes that, regarding the coupling structure between the power means and the structure or the ground in such an allocation mechanism, there may be a delay in the operation of the power means in response to the transmitted control signal, oscillation of the control system when feedback control is adopted, etc. In consideration of this, we are considering configuring a vibration damping device by attaching an elastic means to the power means to generate elastic force in the direction of force transmission.

In other words, the power means causes an extreme delay in operation with respect to the transmitted control signal, especially the high frequency component in the signal, but when the power means and the structure are directly connected, the behavior of the power means is such that the operation is delayed. However, instead of expanding, there is a risk that the shaking of the structure will be amplified. On the other hand, when a resilient means is installed, the behavior of the power means corresponding to high frequency components can be cut by the resilient means, and even if the power means acts in the opposite direction to damping, the behavior can be controlled by the resilient means. It is possible to suppress the adverse effects caused by the delay in the operation of the power means.

In addition, in feedback control, if the feedback signal detected from the structure and used for control contains a high frequency component, it will cause oscillation of the control system, but due to the intervention of the elastic means, the feedback signal detected by the structure and used for control will cause oscillation of the control system. It is possible to cut high frequency components from the signal, improve control stability, and enable the power means to exert sufficient vibration damping action.

By providing the resilient means in this way, the power means responds to the high frequency components included in the control signal, and the shaking of the structure is amplified by the power means that should apply damping force, or the oscillation of the control system causes the power means to respond to the high frequency components contained in the control signal. We are considering a vibration damping mechanism that can prevent the means from being unable to exert sufficient damping action.

(Problem to be solved by the invention) However, in a vibration system in which an elastic means is interposed in the force transmission system of the power means in which seismic force and damping force interact with each other, the elastic means is not provided. Unlike a vibration system, a desirable vibration damping effect cannot be obtained unless the power means is appropriately controlled in consideration of the presence of the resilient means. Therefore, it is desired to devise an appropriate vibration damping control method and device for a vibration system equipped with such an elastic means.

Further, in realizing absolute vibration damping in the vibration damping mechanism described above, it is necessary to pay attention to the following points.

In other words, absolute vibration damping uses the vibration damping force of the power means to maintain the structure in a constant position against ground movement, so the structure remains stationary in space regardless of ground movement.
Although the safety of equipment inside the structure is ensured, the ground motion caused by large-amplitude long-period components (for example, amplitude 40
In the case of a huge earthquake (up to 100 cm, period 20 seconds), there is a problem that isolators that insulate the ground from structures that are displaced relative to each other may be severely deformed and destroyed.

An object of the present invention is to equip a force transmission system of a power means in which seismic force and damping force interact with each other, and to damp a long-period structure with the damping force applied from the power means. ,
It is an object of the present invention to provide a vibration damping control method and apparatus that are suitable for a vibration system including an elastic means and that can realize absolute vibration damping to the extent possible.

(Means and effects for solving the problem) The present invention has a resilient means for resiliently repelling a structure supported on the ground via a long period lengthening means in the direction of force transmission, and the structure and the ground are connected to each other. When damping vibrations using a power means that is driven to expand and contract in the direction of ground motion and transmit damping force to the structure, the seismic motion input to the structure or the seismic motion and the response of the structure due to the input from the power means are detected. After removing the large amplitude component from the detected value, the amount of expansion/contraction displacement of the power means is controlled in accordance with the detected value from which the large amplitude component has been removed.

Then, by controlling the power means after removing large amplitude components from the seismic motion input to the structure to be detected or the response of the structure due to the seismic motion and the input from the power means, it is possible to eliminate excessive While suppressing the occurrence of critical conditions such as deformation, by controlling the amount of expansion and contraction of the power means while taking into account the presence of the explosive means, the function of the explosive means can be utilized to the maximum extent possible. It is designed to achieve absolute vibration damping control.

The present invention also provides a power means that is provided between the ground and a structure supported on the ground via a long period lengthening means, and that is driven to expand and contract in the direction of ground motion to transmit damping force to the structure; an explosive means that is attached to the means and explodes in the direction of force transmission; a detection means that detects seismic motion input to the structure or the response of the structure due to input from the power means; and a detection signal from the detection means. It is configured with a filter that removes large amplitude components, and a control means that controls the amount of expansion/contraction displacement of the power means according to the output signal output from the filter,
After removing large-amplitude components that would be an excessive load on the long-period means, the function of the explosive means is utilized to improve the response of the structure to earthquake motion or seismic motion input to the structure and input from the power means. Based on this, absolute vibration damping control is performed to the extent possible by controlling the expansion and contraction displacement of the power means.

(Embodiments) Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in the figure, a structure 4 is built on the ground 2 in which four sections 1 are formed, supported in the recess 1 via a long period lengthening means 3, and this structure 4 is The period is made longer by the means 3. In this embodiment, as the period lengthening means 3, a plurality of laminated rubbers having an appropriate height and arranged at intervals within the recess 1 are illustrated. Note that the period lengthening means 3 is not limited to laminated rubber, but may also be a sliding support material, a bearing, a soft strip, a magnetic levitation means, or the like.

A power means 5 such as a hydraulic cylinder that is driven to expand and contract in the direction of ground motion during an earthquake to transmit a damping force to the structure 4 is provided between the structure 4 configured in this way and the ground 2. Specifically, the power means 5 operates on the vertical wall 1 of the recess 1.
A and the lower part of the structure 4 facing it, it is provided substantially horizontally along the direction of the earthquake's lateral shaking. Further, a plurality of power means 5 are arranged at intervals around the structure 4 so as to be able to cope with earthquakes of various directions.

A resilient means 6, such as a spring, is attached to the power means 5, and is resilient in the direction of force transmission. In the illustrated example, the resilient means 6 is installed between the power means 5 and the structure 4, but in the direction of force transmission, the resilient means 6 is attached between the power means 5 and the recessed vertical wall 1a on the ground 2 side. It may be between.

The repulsion means 6 is configured such that the vibration of the structure 4 is amplified by the power means 5 which should apply a damping force in response to the high frequency component included in the control signal, or the vibration of the structure 4 is amplified by the oscillation of the control system. It functions to prevent the means 5 from being unable to exert a sufficient damping effect.

On the other hand, this device is equipped with a detection means 7 for detecting the response of the structure 4 due to the seismic motion or seismic motion input to the structure 4 and the input from the power means 5. When seismic motion input to the structure 4 is adopted as a detection target, the detection means 7 detects the ground motion from the ground 2 so that the seismic motion input to the structure 4 during an earthquake (ground motion displacement, ground motion velocity, etc.) can be detected in advance.
installed on the side. In addition, when adopting seismic motion and the response of the structure 4 due to the input from the power means 5 as detection targets, the detection means 7 is installed within the structure 4. A control means 9 such as a computer is connected to the detection means 7 via an amplifier 8 for amplifying the detection signal. This control means 9 is the power means 5
It has a function of performing feedforward control according to the input seismic motion or feedback control according to the response of the structure 4, for the expansion/contraction displacement amount of the power means 5 according to the detection signal from the detection means 7. Feedback control is
The response of the structure 4 due to the action of seismic motion and the action of the power means 5 is constantly detected by the detection means 7, this detected amount is processed by the control means 9, and its control signal is constantly fed back to the power means 5. ing. In addition, the installation position of the amplifier 8 and the control means 9 may be inside the structure 4 as shown in the figure, or may be on the ground 2 side.

Particularly in the present invention, a filter 10 for removing large amplitude components from the detection signal of the detection means 7 is provided between the detection means 7 for detecting various detection targets and the control means 9. As a result, the control means 9 controls the amount of expansion/contraction displacement of the power means 5 in accordance with the output signal output from the filter 10 after removing the large amplitude component from the detection signal.

Here, (1) the concept of the vibration damping method of the present invention, (2) the point that the expansion/contraction displacement amount of the power means 5 is adopted as the control amount of the control means 9, and (2) the function of the filter will be explained.

Regarding (2), the present invention sets a specific control function corresponding to the vibration damping system equipped with the elastic means 6 in the control means 9, and controls the amount of expansion/contraction displacement of the power means 5 based on this control function. It is supposed to achieve the swing.

First, a method will be described in which seismic motion input to the structure 4 is detected in advance and the amount of expansion/contraction displacement of the power means 5 is feedforward controlled using the input seismic motion.

The structure 41 supported by the period lengthening means 3; the basic vibration equation when suppressing the shaking of the structure 4 due to ground motion during an earthquake by applying the control force of the power means 5 is as follows. is expressed in

mi+cx+kx--m9+F... (1) m: Mass specific to the structure 4 C: Damping coefficient specific to the structure 4: Coefficient of elasticity 5C of the period lengthening means 3: Relative velocity X of the structure 4 with respect to the ground 2 :Structure 4
Relative velocity X with respect to the ground 2: Relative displacement of the structure 4 with respect to the ground 2: Ground motion acceleration F: Control force of the power means 5 Here, an elastic means 6 is interposed in the force transmission system of the power means 5. Therefore, the content of the control force F of the power means 5 in equation (1) can be rewritten as follows.

F-ka(z-x)... (2) ka: Resilience coefficient of elastic means 2: Expansion/contraction displacement amount of power means Here, equation (2) is substituted into equation (1). At this time, when the ground motion displacement y and the relative displacement X of the structure 4 with respect to the ground 2 are superimposed, the absolute response displacement, absolute response speed, etc. for a stationary system (absolute system) are summarized as follows.

m (x + y) + c (;c + y
)+ (k+ka)(x+y) - cy+ (k+ka)y+kaz-(3) In equation (3) expressed in this way, the left side is the vibration characteristics in the absolute system of the above structure, and the right side is the content of the external force. It has become. In order for the absolute response of the structure 4 to become zero, the content on the right side, that is, the term of the external force, needs to become zero. In other words,
If the external force term becomes 0, the absolute response of the structure 4 becomes 0.

Therefore, if the right-hand side of equation (3) is set to -0, and the equation is rearranged using the expansion/contraction displacement amount 2 of the power means 5, it is expressed as follows.

c, + (k+ka)y+kaz=0 z--(c y+ (k+ka) y) -(
4) ka This is a control amount that allows the structure 4 to stand still with respect to the absolute system. If this value 2 and the absolute response of the structure 4 are equal, then the expansion/contraction displacement amount 2 of the power means 5 can maintain the structure 4 in a constant position regardless of ground motion (absolute vibration damping). condition).

In this way, in a vibration system in which the elastic means 6 is newly added to the force transmission system of the power means 5 in which seismic force and damping force interact, the newly derived equation (4) is applied to the control means 9. By using the seismic motion input to the structure as the control function and the amount detected by the detection means 7, that is, the ground motion displacement y and the ground motion velocity shi, and performing feedforward control of the expansion/contraction displacement amount 2 of the power means 5, the Taking into account the existence of the means 6, it is possible to output an appropriate vibration damping control signal to the power means 5 while allowing the resilient means 6 to perform its function, and an excellent vibration damping effect can be obtained.

Regarding the above equation (4), the damping coefficient C specific to the structure 4
If cy/ka is extremely small compared to the elastic coefficient ka of the elastic means 6, the value of cy/ka can be ignored and may be omitted for control purposes.

Further, the detection means 7 for detecting the ground motion displacement y and the ground motion velocity 9 may be composed of a displacement meter and a speed meter that detect these values independently, or a single speed meter may be installed and the speed The ground motion displacement y may be detected by integrating the ground motion velocity 9 detected by the meter.

Next, the structure 4 due to earthquake motion and input from the power means 5
A description will be given of how the response of the structure 4 is detected and the amount of expansion/contraction displacement of the power means 5 is feedback-controlled based on the response of the structure 4.

Equation (4) indicating the control function of absolute damping described above may be expressed as follows using the response of the structure 4. That is, in the above equation (4), the value 2 is introduced into the control as the current amount of expansion/contraction displacement of the power means 5, and control is performed based on these values 2 and the response amount of the structure 4. . Therefore, for actual control, this value 2 is set to Za
If this is substituted into the above equation (3) and the control function is rearranged, it becomes as follows.

m (x+y)+c to C+9) + (k+ka) (x+y)= -kaza+kaz z -z a + G f (x + y)
−(5)f (x+y): m
(x+y)+c (M+y)+ (k+ka)
(x+y) G: Feedback gain (G = 1/k a
) This control is based on the amount of response of the structure 4 and attempts to dampen the vibration of the structure 4 in direct response to the input of seismic motion.

In this way, in the vibration system in which the elastic means 6 is newly installed in the force transmission system of the power means 5 in which seismic force and damping force interact, the newly derived equation (5) is applied to the control means 9. By using the response of the structure 4 as a control function and using the response of the structure 4 as the detection amount of the detection means 7 to perform feedback control of the expansion/contraction displacement amount z of the power means 5, taking into account the presence of the explosive means 6, the The power means 5 while causing the means 6 to perform its function.
It is possible to output an appropriate vibration damping control signal to obtain an excellent vibration damping effect.

In addition, when detecting the absolute response amount of the structure 4, as shown in the figure, the detection means 7 installed in the structure 4 detects the absolute acceleration of the structure 4 with respect to the stationary system.

The absolute velocity and absolute displacement may be detected, or the acceleration, velocity, and displacement of the ground motion as well as the relative acceleration, velocity, and displacement of the structure 4 with respect to the ground 2 may be detected using separate sensors and calculated as shown in the above formula. These may be used in combination. Further, the relationship between acceleration, velocity, and displacement may be obtained by, for example, differentiating or integrating the detected velocity.

Regarding (2), next, we will explain the point that the expansion/contraction displacement amount 2 of the power means 5 is adopted as the control amount of the control means 9. As the control gIJ amount when controlling the power means 5 such as a hydraulic cylinder, the displacement amount, There are displacement speed and displacement acceleration. On the other hand, there is also a method of installing a load cell or the like between the power means 5 and the structure 4 to control the acting force generated by the power means 5. If, for example, a hydraulic cylinder is employed as the power means 5, its operation is performed by controlling a valve.

This valve control adjusts the amount of oil inflow, and since the inflow amount corresponds to the displacement speed of the hydraulic cylinder, this valve control controls the displacement speed of the hydraulic cylinder. Therefore, in such a case, it is most direct and simple to set the control amount by the control means 9 to the displacement speed of the power means 5, and this speed control is generally performed. However, as a general concept of control systems, displacement control is less likely to cause oscillation in the control system and has the highest stability. In other words, when considering speed control as a standard, acceleration control has a differential control relationship with respect to speed control, and if the power means 5 can react quickly, it will exhibit excellent followability, but it will be less stable and may cause oscillation. It is a control system that is easy to cause.

Furthermore, the control system for force control is unstable and prone to oscillations, similar to acceleration control. On the other hand, displacement control has an integral control relationship with respect to speed control, has excellent stability, and is less likely to cause oscillation.

In this damping control, by introducing the expansion/contraction displacement amount 2 of the power means 5 into the control equation when deriving the new control function described above, the control of the power means 5 can be achieved by this displacement control. By employing this highly stable displacement control in the above-mentioned vibration damping method, even more excellent vibration damping can be achieved.

Regarding (2), the filter 10 that removes large amplitude components from the detection signal of the detection means 7 functions as follows. In other words, in absolute damping control, it is assumed that the structure 4 is maintained at a constant position regardless of the amount of displacement of the ground 2, as described above. The period lengthening means 3 interposed therein is required to absorb the amount of relative displacement between the ground 2 and the structure 4. In particular, among the vibration components included in seismic motion, long-period components include extremely large-amplitude vibration components, and when the structure 4 is shaking with such large-amplitude vibration components, it is necessary to When the power means 5 is operated and controlled to suppress vibration, the period lengthening means 3 must absorb a large relative displacement, and there is a risk that it will be greatly deformed and damaged.

Here, the filter 10 detects a length that may cause such a large deformation in the period lengthening means 3 from the detection signal detected by the detection means 7 and processed by the control means 9 to become a control signal for the power means 5. Large amplitude components among periodic components are removed. Then, by outputting a signal from which the large amplitude component has been removed to the control means 9, absolute damping control for the large amplitude component is excluded, and damping control that causes large deformation and damage to the period lengthening means 3 is avoided. It looks like this. On the other hand, for long-period components including such large-amplitude components, by having the long-period increasing means 3 take care of the long-period components, the long-period increasing means 3 can perform its original function and provide good immunity. It can make you tremble.

In the actual circuit configuration of the filter 10, the frequency of long-period components that may include such large amplitude components is set in advance in the circuit, and when such vibrations are input as a detection signal, , is configured as a bypass filter that removes vibration components below that frequency.

Furthermore, the circuit configuration of the filter 10 is preferably as follows. If a filter 10 is installed between the detection means 7 and the control means 9, the control timing for a certain frequency will be delayed if the power means 5 is directly controlled by the output signal from the filter 10 due to the phase delay caused by the filter 10. There is a risk that the damping effect will be weakened or the vibrations will be amplified. In order to suppress this influence, it is preferable to set the characteristics of the filter 10 so that this phase delay appears at frequencies with a low probability of occurrence.

From this point of view, the circuit is configured to sense the frequency components of vibrations during actual earthquakes and change the above-mentioned set frequency to be removed at any time so that a phase lag occurs at frequencies with a low probability of occurrence. It is preferable.

As described above, the structure 4 supported on the ground 2 via the long period lengthening means 3 is provided with a springing means 6 for springing the structure 4 in the direction of force transmission, between the structure 4 and the ground 2. Power means 5 that is driven to expand and contract in the direction of ground motion and transmits damping force to the structure 4
In the vibration damping method of the present invention, the detection means 7 detects the seismic motion input to the structure 4 or the response of the structure 4 due to the seismic motion and the input from the power means 5, and the filter 10 After removing the large amplitude component from the detected value, the control means 9 controls the expansion/contraction displacement amount 2 of the power means 5 in accordance with the detected value from which the large amplitude component has been removed.

(Effects of the Invention) In summary, according to the vibration damping method and its device according to the present invention, elastic The newly derived vibration equation that includes the elastic coefficient of the means is used as the control function of the control means, and the seismic motion input to the structure as the detection amount of the detection means or the seismic motion input to the structure and the input from the power means are calculated. By controlling the expansion/contraction displacement of the power means by adopting the response, an appropriate vibration damping control signal can be output to the power means while allowing the resilient means to perform its function, taking into consideration the presence of the resilient means. It is possible to obtain excellent vibration damping effects.

In addition, by introducing the displacement amount of the power means into the control equation when deriving the new control function mentioned above, it is possible to achieve control of the power means with this displacement control, and this highly stable displacement control is adopted for allocation control. By doing so, even better vibration damping can be achieved.

Furthermore, from among the detection signal which is detected by the detection means and processed by the control means and becomes a control signal for the power means, a large amplitude component among the long period components that may cause a large deformation in the lengthening means is filtered. This prevents the long cycle lengthening means from being severely deformed and damaged, and
Accurate absolute vibration damping control can be achieved.

[Brief explanation of the drawing]

The figure is a schematic diagram showing a preferred embodiment of a vibration damping device according to the present invention.

Claims (2)

[Claims] (1) A structure that has a springing means that springs a structure supported on the ground via a long-period means in the direction of force transmission, and is driven to expand and contract in the direction of ground motion between the structure and the ground. When damping vibrations using a power means that transmits damping force to an object, the seismic motion input to the structure or the response of the structure due to the seismic motion and the input from the power means are detected, and large amplitude components are extracted from the detected values. A vibration damping method characterized in that, after removing the large amplitude component, the amount of expansion/contraction displacement of the power means is controlled in accordance with the detected value from which the large amplitude component has been removed. (2) A power means provided between the ground and a structure supported on the ground via a long period lengthening means, which is driven to expand and contract in the direction of ground motion to transmit damping force to the structure; an explosive means that is attached to the power means and springs in the direction of force transmission; a detection means that detects seismic motion input to the structure or a response of the structure due to the input from the power means; A vibration damping device comprising: a filter for removing a large amplitude component from a detection signal; and a control means for controlling an expansion/contraction displacement amount of the power means in accordance with an output signal output from the filter.