JPH0742811B2 - Active damping system with variable stiffness mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention provides a coupling device as a damper capable of switching the damping coefficient in two steps in a column or beam frame of a structure, and when an earthquake causes a vibration disturbance such as wind. On the other hand, the present invention relates to an active vibration control system in which a computer controls the vibration of a structure to reduce the response amount of the structure.

[Conventional technology]

The applicant has incorporated variable rigidity elements in the form of structural members as seismic elements such as braces and seismic walls in the structure of the beam and frame of the structure, and the rigidity of the variable rigidity elements themselves or the connection between the frame body and the variable rigidity elements. An active vibration control system that makes the state variable and analyzes the characteristics of the external vibration force by a computer against the external vibration forces such as earthquakes and winds, and changes the rigidity of the structure to make it non-resonant to ensure the safety of the structure. And various variable rigidity structures have been proposed (for example, JP-A-62-268479,
JP-A-63-114770 and JP-A-63-114771).

[Problems to be Solved by the Invention]

By the way, the conventional active seismic control system mainly focuses on the relationship between the predominant period such as seismic motion and the natural frequency of the structure (usually the first natural frequency is often a problem). By actively shifting the natural frequency of the structure with respect to the cycle, the resonance phenomenon is avoided and the response amount is reduced.

However, especially in the case of earthquake motion or the like, since it is unsteady vibration, it may be considered that the optimal control is not necessarily performed, for example, when the prominent period is not clear or when there are plural prominent periods.

Moreover, in order to minimize the response of the structure by the active seismic control system, it is conceivable to analyze the vibration characteristics such as seismic motion, the characteristics of the frame and the like, and strictly control by various devices. There are naturally limits to control due to various conditions according to seismic characteristics and the structure of equipment, and in such a control system, the mechanism for maintaining safety in the event of an abnormality also becomes complicated There are many problems to be solved in other aspects as well.

INDUSTRIAL APPLICABILITY The present invention efficiently controls a structure by a device having a relatively simple mechanism and a simple program, reduces the response of the structure to a vibration disturbance, secures the safety of the structure, and is comfortable. The purpose is to realize a living space.

[Means for Solving the Problems]

The active vibration control system of the present invention is provided between a frame main body as a column beam frame and a variable rigidity element (hereinafter, simply referred to as a variable rigidity element) as a structural member arranged as a seismic resistant element in the frame main body, or A coupling device, which is interposed in a variable rigidity element provided in the frame body and has a damping coefficient that is variable between a predetermined high damping coefficient and a predetermined low damping coefficient,
Vibration measuring means such as a sensor for measuring the response amount of the frame main body and / or seismic motion due to the input of the external vibration force to the structure, and the response amount and / or the response amount obtained by the vibration measuring means.
Alternatively, the damping coefficient selecting means for selecting one of the high damping coefficient and the low damping coefficient according to the earthquake motion and the control for controlling the coupling device as the damper to a state corresponding to the damping coefficient selected by the damping coefficient selecting means. Command generation means.

According to a second aspect of the present invention, the connection device of the active vibration control system is limited, and the connection device as a damper is composed of a cylinder connected to one of the frame main body or the variable rigidity element and the frame main body or the variable rigidity element. It is composed of a piston of double rod type that is connected to the other and reciprocates in the cylinder, an oil passage that connects the hydraulic chambers on both sides of this piston, and an on-off valve provided in that oil passage. This is a case where the connection state can be switched between a predetermined low damping coefficient and a predetermined high damping coefficient.

In the present invention, as described above, the coupling device as a damper that can switch the damping coefficient in two steps of a predetermined high damping coefficient and a low damping coefficient is interposed, and the response of the structure due to wind or earthquake and the seismic motion are vibrated. While observing with the measuring means, the rigidity and damping effect suitable for it are calculated by the computer, and the damping coefficient of the coupling device is selected.

By actively controlling this, it is possible to secure the rigidity of the structure in the event of a wind or small earthquake, to de-resonate and add damping in the event of a large earthquake, and to realize the seismic control of the structure.

The vibration level is judged only by the response of the structure,
It is possible to control by feedback, or it is possible to perform combined control that combines feedback and feedforward by measuring the earthquake motion itself and performing feedforward.

In the case of claim 2, when the external vibration force of the structure is input,
The response amount of the structure or the column / beam structure is sensed by a sensor such as an accelerometer, a speedometer or a displacement meter as a vibration measuring means, and a damping coefficient selecting means in the computer program determines a high damping coefficient according to the vibration level. One of the lower damping factors is selected. The selected damping coefficient is realized by giving a control command from the control command generation means to the connecting device, that is, by controlling the opening / closing of the opening / closing valve of the connecting device.

As such a coupling device having a variable damping coefficient, for example, a cylinder is coupled to a variable rigidity element side such as a brace, and a rod of a double rod type piston that reciprocates in the cylinder is coupled to a column beam frame body side. A connecting device (hereinafter referred to as a cylinder lock device) can be used. In this cylinder lock device, as shown in FIG. 2, an opening / closing valve 15 is provided in an oil passage 14 connecting the hydraulic chambers 13 on both sides of the piston 12a, and the connection state can be adjusted by opening / closing the opening / closing valve 15. it can. That is, when the on-off valve 15 is closed,
Since the flow of pressure oil in the oil passage 14 is substantially blocked,
The state becomes almost fixed, and the device has a large damping coefficient. On the contrary, when the on-off valve 15 is open, both hydraulic chambers 13
The pressure oil flow is substantially free and the device will have a small damping coefficient.

In the cylinder lock device 10 using this hydraulic pressure,
The damping force for the main body of the column / beam structure is given as a resistance force proportional to the square of the relative speed of the cylinder 11 and the piston rod 12.

The same applies to the case where the cylinder 11 is connected to the column beam frame body side and the piston rod 12 is connected to the variable rigidity element side.

[Action]

In the active vibration control system of the present invention, the coupling device is activated depending on the response of the structure or the magnitude of vibration such as seismic motion, and fixed or fixed with a large damping coefficient for wind and small earthquakes. By dealing with it in a state close to, the rigidity of the structure can be secured and a large damping force can be exerted. On the other hand, for large earthquakes, by dealing with a free or near free state with a small damping coefficient, the column-frame structure of the structure is made into a low rigidity state where the variable rigidity element does not work, and in addition to achieving non-resonance, The response of the structure can be reduced by adding damping according to the vibration level of a large earthquake.

That is, while the active damping system of the present invention emphasizes non-resonance in the conventional active damping system,
The connection state of the connecting device is controlled according to the vibration level, the control is relatively simple, and the damping force to the structure can be effectively exerted.

〔Example〕

Next, a specific example of the control system will be described as an example.

FIG. 1 shows the outline of the configuration of the active vibration control system of the present invention. The main body 2 of the beam / column structure composed of the columns 3 and 4 and the variable stiffness element incorporated in the main body 2 of the beam / column structure of each layer. The connecting device 1 (for example, the cylinder locking device described above) is interposed between the connecting device 1 and the inverted V-shaped brace 5. The input seismic motion and the response (amplitude, velocity, acceleration, etc.) of the structure are sensed by the input sensor 6 and the response sensor 7 installed in the structure, respectively, and the coupling device 1 according to the vibration level is detected.
The computer 8 selects the damping coefficient or the connection state of and the control command is issued.

More specifically, the control is performed as follows.

In case of wind or small earthquake, the damping coefficient of the device is set to a high value,
The structure will have a high rigidity with variable rigidity elements. As a result, the seasickness phenomenon, which is a problem in high-rise buildings, can be prevented and a comfortable living space can be realized.

If a large earthquake is judged based on the response of the structure being sensed and the magnitude of the seismic motion, the damping coefficient of the device is switched to a smaller value, and the structure with low rigidity where the variable rigidity element does not work is constructed. As a result, the natural period of the beam-column structure becomes long, and in view of the general characteristics of earthquake motion, the force that enters the structure is reduced and safety is maintained.

The switching of the damping coefficient of the equipment can be judged only by the magnitude of the seismic motion and the magnitude of the response of the structure, and as a computer, a board computer is sufficient.

The damping performance can be added to the beam structure in both high and low damping coefficient states of the device, and it is effective in reducing the response of the structure.

FIG. 3 to FIG. 10 show examples of application positions of the connecting device of the present invention to the column-beam frame.

In the example of FIG. 3, the connecting device 1 is interposed between the column beam frame as the frame main body 2 and the inverted V-shaped brace 5 as the variable rigidity element.

The example of FIG. 4 is a moment-resisting frame as a variable rigidity element, with the coupling device 1 interposed between the column-beam frame as the frame body 2 and the frames 21 standing or hanging from the upper and lower beams 4. Is the case of configuring.

In the example of FIG. 5, the coupling device 1 is interposed between the column-beam frame structure as the frame body 2 and the RC seismic wall 22 as the variable rigidity element.

The example of FIG. 6 is an example of the case where the coupling device 1 is provided in combination with the base isolation rubber 23 such as laminated rubber at the base of the base isolation structure.
The coupling device 1 plays a role of a damper in the seismic isolation structure. The variable stiffness element in this case can be considered the basis of the structure.

In the example of FIG. 7, an X-shaped brace 24 provided in a column-beam frame as the frame main body 2 is a variable rigidity element, and the coupling device 1 is laterally (horizontally) interposed in the center of the X-type.

Similar to the example of FIG. 7, the example of FIG. 8 is an example applied to the X-type brace 25. In contrast to the example of FIG. The device is installed vertically and is vertical.

The example of FIG. 9 is similar to the example of FIG. 5 in that the connecting device 1 is interposed between the beam-frame structure as the frame body 2 and the RC seismic wall 26 as the variable rigidity element. The feature is that 1 is provided above the opening 27 such as the entrance and exit.

In the example of FIG. 10, the connecting device 1 is interposed in the center of the X-shaped brace 28 in the large frame, and the middle girder 29 and the brace 28 are separated.

〔The invention's effect〕

The active seismic control system of the present invention controls disturbances such as earthquake motions in consideration of the damping property of the structure. By incorporating in the computer and setting conditions such as the vibration level for switching in advance in the computer, control can be performed relatively easily according to the vibration state.

That is, by changing the damping coefficient of the coupling device, the coupling state of the variable rigidity element and the coupling device is changed, and by giving damping properties according to the characteristics of the structure and the characteristics such as seismic motion, the response of the structure The amount can be reduced, safety can be ensured, and a comfortable living space can be realized.

Moreover, since the control is performed by a relatively simple determination such as the vibration level, the control can be performed by a simple computer, which is economical.

[Brief description of drawings]

FIG. 1 is a schematic diagram of the configuration of the active vibration control system of the present invention,
FIG. 2 is a conceptual diagram of a cylinder lock device used in the active vibration control system of the present invention, and FIGS. 3 to 10 are outlines showing examples of application positions of a connecting device used in the present invention to a column beam structure. It is a figure. 1 ... Connection device, 2 ... Frame body, 3 ... Pillar, 4 ...
Beam, 5 ... Brace, 6 ... Input sensor, 7 ... Response sensor, 8 ... Control computer, 10 ... Cylinder locking device, 11 ... Cylinder, 12 ... Piston rod, 13 ... Hydraulic chamber, 14 …… Oil passage, 15 …… Open / close valve

Claims (2)

[Claims] 1. A frame main body as a column beam frame and a variable rigidity element as a structural member arranged as a seismic element in the frame main body, or interposed between variable rigidity elements provided in the frame main body, A coupling device as a damper whose damping coefficient is variable between a predetermined high damping coefficient and a predetermined low damping coefficient, and vibration measurement for measuring the response amount and / or seismic motion of a frame body by inputting a vibration external force to a structure. Means, damping coefficient selecting means for selecting one of the high damping coefficient and the low damping coefficient according to the response amount and / or the seismic motion obtained by the vibration measuring means, and the coupling device for selecting the damping coefficient. An active vibration control system by a variable stiffness mechanism comprising a control command generating means for controlling to a state corresponding to a damping coefficient selected by means. 2. The connecting device comprises a cylinder connected to one of a frame main body and a variable stiffness element, and a double rod type piston connected to the other of the frame main body or the variable stiffness element and reciprocating in the cylinder. An oil passage connecting hydraulic chambers on both sides of the piston and an opening / closing valve provided in the oil passage. By opening / closing the opening / closing valve, a connection state is established between a predetermined low damping coefficient and a predetermined high damping coefficient. The active vibration control system according to claim 1, which is switchable.