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Proceedings of the International Conference on
Advances and New Challenges in Earthquake
Engineering Research, Hong Kong Volume
APPLICATION OF SEMI-ACTIVE DEVICES IN STRUCTURES
SUBJECTED TO EARTHQUAKES, WIND AND VIBRATIONS
Oliver Nagel
Maurer Soehne GmbH & CO KG
Frankfurter Ring 193
D 80 807 Munich, Germany
www.rnaur@r-soehne.de, nagel@mcrin.maurer-soehne.de
ABSTRACT
During the European community research programme SPACE, "smart" devices for mitigating the
influence of vibrations on structures are developed. This paper describes the development of a
magnetorheological damper and its practical application for the damping of a pedestrian bridge in
Germany. Beyond that, in the project the improvement of the seismic behaviour of a steel railway
bridge by replacing the existing passive hydraulic dampers by MR-dampers was investigated. Reason
for this development is that the occurring earthquakes in the recent past were much stronger than the
design earthquakes. Furthermore, a new kind of magnetic valve was developed which led to a
considerable improvement of the dampers properties regarding the response force. Additionally,
shake-tabie-tests with a 2-floor steel structure model (scale 1:5) were performed.
1 INTRODUCTION
The SPACE Project "Semi-active and Passive Control of the dynamic behaviour of structures
subjected to Earthquakes, wind and vibrations", financed by the European Union, has its main
objective in developing devices to mitigate the effects of earthquakes and other disturbing vibrations.
The following systems are in the process of being developed in the course of this project:
• A semi-active damper, based on magneto-rheological fluids, especially suited to seismic highdemand
applications
• An improved passive-floor isolation system, based on high damping elastomeric bearings
• A hybrid system, combining both passive and semi-active devices
To achieve the named objectives, it also has to be worked out (among others):
• Suitable materials (e.g. stable magnetorheological fluid)
• Suitable real time control algorithms and electronic hardware for different types of structures
This paper concentrates on the semi-active damper and the developments in this connection.