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Resume
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Objectives
of Seismically Excited Highway Benchmark Problem on Structural Control
A highway overcrossing or bridge,
connecting major transportation routes, is a key node in transportation
network. It must continue to function after an earthquake. Therefore, a
higher level of performance with less structural damage is required for such
bridges. Recent earthquakes such as Northridge and Kobe have demonstrated the importance of
maintaining the operation of bridge structures. To deal with seismic risk to bridges,
seismic upgrading of critical highways is under way by various state and
federal agencies, and considerable attention has been paid to research and
development of effective protective systems.
For highway bridges, seismic isolation bearings in combination with passive,
semi-active and active control systems are used as protective systems. The seismic isolation bearings, which
usually replace conventional bridge bearings, decouple the superstructure
from piers and abutments during earthquakes, thereby significantly reducing
the seismic forces induced in the bridge structure and lowering the strength
and ductility demands on the bridge.
However, nonlinear behavior of the bridge columns or excessive
displacement of bearings during near-fault ground motions may result in
significant damage to the bridge with isolation bearings. Hence, it is important to investigate the
effectiveness of various protective systems in reducing response quantities
of highway bridges.
To meet this objective, it was decided
to develop a benchmark structural control model for highway bridges during
the meeting of the ASCE Committee on Structural Control during the 2003
Structures Congress in Seattle.
This paper presents the problem definition for the benchmark highway
bridge. The highway bridge model is based on the newly constructed 91/5 highway bridge
in southern California bridge to provide systematic and standardized
means by which competing control strategies, including devices, control
algorithms and sensors, can be evaluated.
The benchmark package consists of the MATLAB based 3-D finite element model of the highway
bridge, design of sample controllers, prescribed ground motions and a set of
evaluation criteria.
Please feel free to contact us if you are interested in participating in the
benchmark study or if you encounter any problem in downloading the data.
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