JPH0617598B2 - Axial variable stiffness material for building frame - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an axially variable stiffness material used in a building structure having a vibration control structure, and a member according to an external force of vibration such as an earthquake or wind input to a building. The rigidity of the is changed to deal with earthquakes.

[Conventional technology]

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

Seismic resistant methods include seismic isolation or damping methods in which laminated rubber bearings and dampers are interposed between the building and foundation, methods of consuming seismic energy by destroying non-major components of building components, walls or columns. Etc., with slits,
There is a method to adjust the building to the optimum rigidity.

By the way, the confirmation of the safety of a building designed by the current seismic design method during an earthquake is based on the basic idea that the absorbed energy due to the hysteresis characteristic accompanied by plasticization of the structure exceeds the earthquake energy acting on the structure. However, this has a reliability problem with respect to the history loop characteristic.

In addition, all of the conventional methods provide a passive seismic resistant structure against natural external forces such as earthquakes and winds, and because the building has a specific natural frequency, resonance phenomena are generated in response to uncertain inputs such as earthquakes. You cannot avoid it.

On the other hand, in the Japanese Patent Application No. 61-112026, the applicant changed the rigidity of the building itself based on the judgment of the response prediction system based on the detected seismic motion instead of the passive seismic resistance method as described above, and the resonance It proposes a seismic control method that keeps the building and equipment inside the building, the resident, etc. safe by keeping it outside the area or in a state where there is little resonance.

In the above-mentioned seismic control method, a control device whose connection state is changed according to a command from a computer is provided between all or part of columns, beams, braces, walls and their joints, or between a building and a foundation or an adjacent building. , Damping the building is done as follows.

The invention of the earthquake is detected by an earthquake detection device located in a narrow area and a wide area around the building, and the observation data is transmitted to the computer through a wired or wireless communication network. The wide area seismic detector is connected to the seismograph at the existing seismic observation point or a specially installed seismometer by a micro line or a telephone line. The narrow-area seismic sensing device is composed of a seismograph installed around the building or in the surrounding ground, and a vibration sensor installed in the building base or inside the building. The influence of wind force is detected by the vibration sensor inside the building.

With respect to the detected earthquake, the computer determines the scale of the earthquake, analyzes the frequency characteristics, predicts the response amount, etc., bypasses the resonance regarding whether or not to control the building vibration, and the control amount when it should be controlled, It is judged that the optimum rigidity (natural frequency) with a small amount of vibration response is given.

The controller's command is transmitted to the controller of each part of the building, and the controller is operated so that the rigidity of the building becomes the optimum rigidity based on the computer's prediction. For adjusting the connected state, the fixed state and the released state are adjusted by turning on and off with a hydraulic mechanism, electromagnet, etc., and the hydraulic mechanism is used for the outside of the fixed state, the released state, the introduction of tension force and the fixing at any position. Alternatively, a special alloy or the like may be used for adjustment.

Further, the vibration sensor arranged in the building can detect the response amount in each part of the building and the actual vibration when the control is performed, and the feedback can be used to correct the control amount.

[Object of the Invention]

The present invention is used for a brace or a pillar in a building structure having a vibration control structure, and changes the rigidity of the building structure by changing the rigidity according to an external vibration force such as an earthquake or wind, thereby changing the rigidity of the building structure to prevent an earthquake or wind. Reduce the response of the building due to vibration external force,
An object of the present invention is to provide a variable axially rigid material for a building frame, which is suitable for realizing a comfortable living space, has a good fit in the building frame, operates instantly, and can fully exert its function. It is what

[Structure of Invention]

The outline of the present invention will be described below with reference to FIGS. 1 (a) and 1 (b) showing the basic structure.

The axial direction variable rigidity material A of the present invention has pin joints 5a and 5b formed in the middle thereof, respectively, and main members 1 and 2 facing each other in a V shape and a connection arranged between the pin joints 5a and 5b. And member 3. Both ends of the main members 1 and 2 have the pin joint portions 4a and 4b in common, and the pin joint portions 4a and 4b
It has a structure that receives an axial force N from 4b. The connecting member 3 arranged between the intermediate pin joints 5a and 5b is the pin joint 5
It is pin-joined to one of the pin joints a and 5b, and is detachable from the other pin-joint. That is, the variable stiffness material A has a stable structure when the connecting member 3 is engaged, and the variable stiffness material A has an unstable structure when the coupling member 3 is disengaged and does not resist the axial force N.

The members 1a, 1b, 2a, 2b and the connecting member 3 forming the main members 1 and 2 each determine a cross section so as to have a basic axial rigidity that can resist the axial force N as a stable structure. Further, the basic rigidity as the axial force resistance material when the variable rigidity material A has a stable structure is also based on the angle θ bent (a angle formed by the axial direction and the members forming the main members 1 and 2). You can choose.

When considering the engagement and disengagement only at the end of the linking member 3, the change in rigidity is a change between the O rigidity and the basic rigidity. If it can be engaged and disengaged at a composite position, it is possible to select a plurality of stages of rigidity as the axial force resistance material.

Further, the connecting member 3 is a combination of two tensile resistance materials 3a that resist the movement of the intermediate pin joints 5a and 5b outward in the material axis direction and a compression resistance material 3b that resists movement in the material axial direction inward. One of them may be one that resists pulling and compression.

The engagement / disengagement of the connecting member 3 to the pin joints 5a and 5b can be switched by rotating the servomotor, the pulse motor or the like (see FIG. 7 (a)) or the linear movement by the hydraulic cylinder or the like (FIG. 7 (b)). (See) and the like, and the drive device is not limited. In order to avoid the resonance phenomenon of the building due to an earthquake, it is effective to engage and disengage the connecting member 3 when it is desired to change the rigidity moment by moment. That is, based on the control program of the computer,
The connection state by the connection member 3 can be automatically controlled,
Resonance can be avoided by changing the rigidity, connection state, etc. of members in each part of the building in accordance with an external vibration force such as an earthquake to change the natural period of the entire building.

[Work]

In FIGS. 1 (a) and 1 (b) described above, the tensile resistance material 3a as the connecting member 3 is rotatable around the pin joint portion 5a, and the locking portion 6a at the tip is outside the pin joint portion 5b. , The compression resistance member 3b is rotatable around the pin joint portion 5b, and the locking portion 6b at the tip end engages with the inside of the pin joint portion 5a and acts as follows.

(1) FIG. 2 (a) shows the case where both the tension resistance material 3a and the compression resistance material 3b as the connecting member 3 are disengaged, in which case the variable stiffness material A has an unstable structure, As shown in FIG. 2 (b), there is no resistance to the axial force N, that is, the rigidity is 0.

(2) FIG. 3 (a) shows the case where only the compression resistance material 3b is engaged. In this case, when the axial force N in the pulling direction acts on the variable stiffness material A, the compression resistance material 3b works, As shown in FIG. 3 (b), the variable stiffness material A exhibits tensile resistance. Axial force in compression direction N
Do not resist against.

(3) FIG. 4 (a) shows the case where only the tensile resistance material 3a is engaged, and in this case, when the axial force N in the compression direction acts on the variable stiffness material A, the tensile resistance material 3a acts and As shown in FIG. 4 (b), the variable stiffness material A exhibits compression resistance. Axial force in tensile direction N
Do not resist against.

(4) FIG. 5 (a) shows a case where both the tensile resistance material 3a and the compression resistance material 3b as the connecting member 3 are engaged, and in this case, the pin joint portions 5a and 5b are simply connected. As in the case where the variable rigidity material A is present, as shown in FIG. 5 (b), the variable stiffness material A can resist tension and compression.

(5) Due to the engagement / disengagement of the connecting member 3, the above states (1) to (4) are variable, and the deformation characteristics of the variable stiffness material A are as shown in FIG. 6, and it is possible to change the stiffness in two steps. Become.

A change in rigidity when there are a plurality of engagement / disengagement positions of the connecting member 3 can be considered in the same manner, and it is possible to change the rigidity in a plurality of steps.

〔Example〕

FIGS. 8 and 9 (a)-(d) show a specific embodiment of the present invention, which is a member 1a made of H-section steel processed by removing webs at both longitudinal ends. , 1b, 2
a and 2b are connected by pin joints 4a, 4b, 5a and 5b, and the bases of the compression resistance material 3b and the tension resistance material 3a as connecting members are attached to the intermediate pin joints 5a and 5b, respectively.

The compression resistance material 3b has a pin joint portion 5 with an intermediate base portion at the rear end.
It is rotatable about the axis of a, and a pulley 1 is provided through a motor 9 fixed to a member 1a through an installation plate 10.
1, the belt 13 and the pulley 12 on the side of the compression resistance material 3b are rotated to perform a rotation operation. An L-shaped locking portion 6a is formed at the tip of the compression resistance material 3b, and can be engaged with the inside of the shaft of the pin joint portion 5b facing each other by the rotation of the compression resistance material 3b.

On the other hand, in the tensile resistance material 3a, similarly, the base portion at the rear end is rotatable about the axis of the intermediate pin joint portion 5b.
It is rotated by the motor 9 fixed to b, and the reverse L
The V-shaped engaging portion 6b engages with the outer side of the shaft of the pin joint portion 5a that faces it.

In FIG. 9 (a), reference numerals 14 and 15 are for preventing the locking portion 6b of the compression resistance material 3b and the locking portion 6a of the tension resistance material 3a from being displaced outward in the axial direction of the pin joint portions 5a and 5b. It is a stopper. In this embodiment, FIG. 9 (d)
As shown in Figure 3, the compression resistance material 3b is an H-shaped steel, the tension resistance material 3a
Consists of two channel steels.

FIG. 10 shows an example of application to a brace of a building frame, in which the variable rigidity material A of the present invention is arranged on a diagonal line surrounded by columns 16 and beams 17. By analyzing the ground motion that changes from moment to moment at the time of an earthquake with a computer and sending an instruction to the variable rigidity material A to change the connection state,
The rigidity can be changed and the resonance can be avoided.

FIG. 11 shows a variable-rigidity material A'that can change the rigidity in multiple steps.
This is an example of. FIGS. 12 (a) to 12 (f) show how the rigidity changes, and the tensile resistance material 3a 'as the connecting member 3 is rotatable around the pin joint 5a.
Any of the three locking portions 8a, 8b, 8c near the tip can be engaged with the outside of the pin joint portion 5b, and the variable rigidity member A'provides O rigidity with respect to the axial force N in the compression direction. Including 4
It is possible to change the rigidity in stages. The compression resistance material 3b 'is rotatable around the pin joint portion 5b, and the compression resistance material 3b' is provided near the tip end.
Any of the locking portions 7a, 7b, 7c at the location can be engaged with the inside of the pin joint portion 5a, and the variable rigidity member A ′ can change the rigidity in four steps even with respect to the axial force N in the pulling direction. It is possible. FIG. 13 shows the axial force N acting on the variable stiffness material A '.
And the displacement δ of the variable rigidity member A ′ in the axial force N direction.

In the above example, the variable resistance material 3 is composed of two members, but as shown in FIG.
It is also possible to resist pulling and compression in the engaged state.

[Effects of the invention] By using it for columns and braces of a building frame with a vibration control structure, the rigidity as a member and the rigidity of the building frame are changed, and the natural period of the building is changed according to individual seismic characteristics, and resonance occurs. It is possible to suppress a large change in the building due to the phenomenon.

By the engagement and disengagement of the connecting member, it is possible to change between an unstable structure state and one or more stable structure states, and a two-stage or multiple-stage rigidity can be obtained as the member.

Due to the structure in which the rigidity is changed by engaging and disengaging the connecting member by the operation of the driving device that is controlled according to the vibration external force such as earthquake motion, it is possible to instantaneously change the rigidity in two or more steps. While responding to the ever-changing,
It can provide effective seismic control.

Since the rigidity change of the member is performed at the pin joint portion located in the middle of the member, it does not interfere with the joint with other members constituting the building frame, and can be well accommodated in the frame.

[Brief description of drawings]

1 (a) and 1 (b) are front views showing the basic structure of the present invention, and FIGS. 2 to 6 are views for explaining the operation of the present invention.
2 (a), 3 (a), 4 (a), and 5 (a) are front views, 2 (b), 3 (b), and 4 ( b), Fig. 5
(b), and FIG. 6 are graphs showing the relationship between axial force and displacement,
7 (a) and 7 (b) are front views showing the operating method of the connecting member, FIG. 8 is a front view of one embodiment, and FIGS. 9 (a), (b), (c), and (d). Are lines I-I, II-II, III-III, and IV in FIG. 8, respectively.
-End view along line IV, FIG. 10 is a front view showing an example of application to a brace, FIG. 11 is a front view in the case where a connecting member enables resistance in multiple stages, and FIGS. ) Is a front view showing various resistance states, FIG. 13 is a graph showing the relationship between axial force and displacement in that case, and FIG. 14 is a front view when resistance is applied by a single connecting member for both tension and compression. It is a figure. A: variable rigidity material, 1, 2 ... main member, 3 ... connecting member, 4a, 4b ... pin joint portion, 5a, 5b ... pin joint portion, 6a, 6b ... locking portion, 7a, 7b, 7c, 8
a, 8b, 8c ... Locking part, 9 ... Motor, 10 ... Motor installation plate, 11, 12 ... Pulley, 13 ... Belt, 1
4,15 …… Stopper

Claims (2)

[Claims] 1. An axially variable stiffness material which constitutes a building frame having a vibration control structure and whose rigidity is changed by the operation of a drive device so as to change the rigidity of the building frame in accordance with an external vibration force. Pin-joining ends of the main members facing each other in a V shape having pin joints are made to have a common pin-joint portion at both ends receiving the axial force, and one pin-joint portion is provided at the intermediate pin-joint portion. A coupling member that is pin-joined and is disengageable between a state in which it is engaged with the other pin-jointed portion and a state in which it is disengaged, and the engagement / disengagement of the coupling member controlled by external vibration force. A variable-rigidity material in the axial direction of a building frame, which is provided with a drive device for switching between. 2. The axially variable rigidity material for a building frame according to claim 1, wherein the connecting member is engageable with and disengageable from the intermediate pin joint portion at a plurality of positions to enable resistance in a plurality of stages.