EP1800020A1

EP1800020A1 - Device for damping vibrations in a building

Info

Publication number: EP1800020A1
Application number: EP05787249A
Authority: EP
Inventors: Uwe Starossek
Original assignee: Technische Universitaet Hamburg TUHH; Tutech Innovation GmbH
Current assignee: Soletanche Freyssinet SA
Priority date: 2004-09-15
Filing date: 2005-09-14
Publication date: 2007-06-27
Also published as: WO2006029851A1; KR20070053806A; DE102004045433B3

Abstract

The aim of the invention is to create a device for damping vibrations, which can dampen and eliminate vibrational states better than previously known devices by being excited in a self-induced or externally induced manner, thus improving stability, durability, and usability while providing great reliability and using simple means and as little energy as possible. Said aim is achieved by a device for damping vibrations in a building, which comprises the following: at least one couple of mass elements (18) that are disposed on opposite sides of a rotating pin or swivel pin (16) around which the vibration is dampened. The mass elements are fixed to the ends of a beam (14) that is mounted so as to be rotatable about the rotating pin or swivel pin. The rotations or vibrations of the beam are predefined or influenced actively by means of an actuator (22) and/or passively by means of spring elements and/or damping elements.

Description

Device for damping oscillatory motion in a building

The invention relates to a device for damping oscillatory movements in a building, in particular in a bridge.

There is a need for ever larger spans in bridge construction. For example, in the late 1990s, the Akashi Kaikyo Bridge, built in Japan, has a span of nearly 2000 meters. The bridge planned to cross the strait of Messina in Italy will have a span of over 3 km. With these extreme bridge lengths, the problem of the susceptibility to vibration of these structures is increasingly coming to the fore. In the design of wide-span bridge girders, a particularly important effect is the so-called chipping stability of the bridge. This is an aeroelastic phenomenon in which self-induced, coupled bending and torsional vibrations or decoupled torsional vibrations of the bridge girder occur. Self-induced vibrations, in contrast to so-called externally induced vibrations, which are caused for example by gusts of wind or by periodic vortex shedding, are excitation forces, which are caused by a displacement of the bridge. The air forces acting on the structure influence the dynamic properties of the aeroelastic overall system, ie in particular stiffness and damping parameters. These changes occur even at constant wind speed. If the wind speed reaches a certain critical value, the damping of the bridge carrier is canceled. As wind speed continues to increase, a system with negative overall attenuation may occur in which a small initial displacement results in an increasing vibration of nearly unlimited amplitude, thus failing the bridge structure. The critical wind speed (Ucr) is the structural characteristic for the flutter stability of bridges. It is known that Ucr decreases with decreasing stiffness and damping of the bridge. Straight bridges with a large span, however, have a low rigidity, so that the problem of fluttering occurs for them.

To stabilize fly-endangered bridge girders various vibration damping methods and devices can be used. In principle, active and passive methods can be distinguished. The passive vibration damping refers essentially to structural measures, such as increasing the Torsionssteifϊgkeit the carrier or the addition of additional stay cables. It is also known to provide passively oscillating additional masses, so-called absorbers, as passive vibration damping in the narrower sense.

The active vibration dampers can be divided into active mechanical and active aerodynamic vibration dampers. The latter are based on the approach of suitably modifying the flow field forming the bridge carrier so as to achieve a stabilizing effect. For example, can be provided on the bridge girder side flaps, which are placed in the wind that a stabilizing force is exerted by the passing air. In the case of the active mechanical flutter control, for example, the torsional vibration of the bridge girder is checked by an additionally applied torsional moment. For an embodiment, the additional torsional moment is generated by horizontally displaceable damper masses in the bridge girder. There are also considerations to create a stabilizing torque for the bridge girders by means of a mass rotating in the center of the bridge cross-section. The devices mentioned have the disadvantage among others a relatively large energy requirement and thus reduced reliability.

In addition to the above-described critical phenomenon of fluttering in bridges, similar vibrational phenomena also occur in buildings, where these are then referred to as galloping. In addition to these vibrational phenomena endangering stability, construction-related and structural structures also involve wind, traffic, earthquakes and other external influences, causing externally induced vibrations which can impair both their usability and stability, and which must also be damped and suppressed.

The invention has for its object to provide a damper device for damping a vibrational motion to provide better than known devices, with high reliability with simple means and the lowest possible use of energy occurring vibration conditions due to self-induced and / or externally induced excitation attenuate and suppress Stability, durability and usability thus can improve.

According to the invention the object is achieved by a device having the features of claim 1. Advantageous embodiments form the subject-matter of sub-claims 2 to 11.

The erfmdungsgemäße device for damping oscillatory movements in a building and / or structure has at least one pair of mass bodies, which are arranged on opposite sides of a randomly oriented in space rotation or vibration axis. The axis of rotation or oscillation in this case runs through the building and / or supporting structure in such a way that the oscillation movement to be damped at least with a substantial part about this axis he follows. The mass bodies are attached to the ends of a beam which is rotatably mounted about the axis of rotation or vibration. In order to move the beam around a bearing, this is preferably a pivoting or rotational movement, an actuator is provided, which acts on the beam. In a vibratory motion of the construction and / or structure of the beam is offset with the mass bodies by the actuator in a swinging swinging motion or in a rotational movement. With a suitable coordination of the moments of inertia and the movement occurs by the beam with the mass bodies, a vibration damping effect.

For effective control of the Akruators at least one sensor connected to the control is provided, the position and / or movement of the building in the translational and rotational degrees of freedom detected, in particular, a sensor may be provided for detecting the corresponding accelerations. Based on the applied sensor data, the controller can then determine both amplitude, and frequency and phase of a movement of the bar or specify this directly in the time domain.

For controlling the movement of the bars, one or more sensors may additionally be provided which detect the position and / or movement of the bar and pass it on to the controller. Here too, acceleration sensors can be provided as motion sensors.

In a preferred embodiment, a spring element and / or a damper element is additionally coupled to the beam in order to match the movements of the beam and its natural frequencies to those of the structure or the structure. In a preferred embodiment, the actuator can be decoupled from the additionally provided with spring and / or damper element beams, for example, in case of failure of the drive still to achieve a passive damping effect, or to save energy in times of small vibration excitation forces. The device according to the invention can then also be regarded as a turntable and be designed accordingly.

In a preferred embodiment, the beam with the mass bodies is arranged in a container which provides fastening means for connection to a building or supporting structure. Such a "mobile" damper device makes it possible, in particular, to achieve vibration damping even during construction on the supporting structure, and the position of the damping device can be adapted in accordance with the progress made in the construction and the statics which change with it.

To be particularly advantageous, it has also been found to provide structures or structures with several of the devices described for vibration damping. Preferably, the control of the actuators of the devices can be carried out coordinated, in which case the spatial behavior of the building structure or structure can be taken into account.

Preferred embodiments of the device according to the invention will be explained in more detail with reference to drawings. It shows:

1 shows a schematic section through a longitudinal axis of a bridge girder,

Fig. 2 shows a further embodiment of the damping device in Brückenquer¬ cut and Fig. 3, the damping device in a container.

Fig. 1 shows a cross section through a bridge carrier hollow box 10, in the center of a bearing base 12 is arranged. On the bearing base 12, a beam 14 is rotatably supported via a bearing 16. At the ends of the beam 14, two bodies 18 are attached to a mass m. In the illustrated embodiment, the mass m of the body 18 is equal. However, this is by no means necessary. In buildings in which not only rotational vibrations, but also translational vibrations occur, such as in buildings under seismic action, it is also conceivable to use mass body with different weights. Likewise, it is conceivable to arrange the two mass bodies at different distances from the bearing pedestal, thus to support the beam asymmetrically with respect to the bearing pedestal. To the bearing 16, the mass body 18 are pivoted in the direction 20 or rotated. The pivot or rotation angle can be limited by suitable means (not shown) or be of unlimited size, in the latter case, a rotational movement is considered.

Fig. 1 further shows an actuator 22, which can operate, for example, electrically, pneumatically or hydraulically to move the beam 14. In the case of a rotational movement of the actuator is in the axis of rotation of the beam.

The actuator 22 is controlled by a control device 24 shown schematically. The control device 24 is connected to two sensors 26, which measure the acceleration of the structure. The acceleration values are forwarded to the controller 24 and serve to determine the vibration states and to control the actuator 22 with a corresponding counterphase. FIG. 2 shows a further development of the damping device from FIG. 1, in which case the same elements have been identified with the same reference numerals.

In addition to the actuator 22, the balance beam 14 is still coupled to a spring element 28 and a damper element 29. In Fig. 2 spring and damper element are shown only schematically. Of course, it is possible to distribute two or more springs along the balance beam, in which case the individual spring constants add in their D attenuation effect to the spring constants shown in Fig. 2 or to arrange a torsion spring in the axis of rotation. Likewise, two or more damper elements can be distributed along the balance beam.

Fig. 3 shows essentially the damping device of Fig. 2 in a container 30 which is fixed to the bridge girder The container 30 may be, for example, a standard 40 'container that is detachably connected to the bridge girder 10.

Claims

Claims:

A device for damping oscillatory motion in a structure, comprising: at least one pair of mass bodies (18) disposed on opposite sides

Sides of an arbitrarily oriented in space rotation axis are arranged around which the damping of the oscillatory motion takes place, wherein the mass body (18) are fixed to the ends of a beam (14) which is rotatably mounted about the rotation axis, wherein at least one actuator (22) is provided, the the beam (14) to a

Bearing (16) moves.

2. Apparatus according to claim 1, characterized in that the actuator (22) via a controller (24) is driven such that an occurring vibration movement is damped or eradicated.

3. Apparatus according to claim 2, characterized in that a sensor (26) is provided, the position and / or movement of the structure detected and forwarded to the controller (24).

4. Apparatus according to claim 2 or 3, characterized in that at least one additional sensor is provided, detects the position and / or movement of the beam (14) and forwards to the controller (24).

5. Device according to one of claims 1 to 4, characterized in that in addition at least one spring element (28) and / or a damper element (29) with the building and the beam (14) is coupled.

6. Device according to one of claims 1 to 5, characterized in that the movement of the mass body takes place in a limited angular interval.

7. Apparatus according to claim 5 or claim 6, based on claim 5, characterized in that the actuator (22) can be decoupled from the beam (14).

8. Device according to one of claims 1 to 7, characterized in that the beam (14) with the mass bodies (18) in a housing (30) is arranged, which is provided with fastening means for releasable connection to the building.

9. Building, which is provided with one or more devices according to one of claims 1-8.

10. Structure according to claim 9, characterized in that at least two devices have an actuator (22) whose control is coordinated.

11. Structure according to claim 9 or 10, characterized in that at least one device is mounted before completion of the structure on or in this and is operated.